1. Introduction
The demand generated by an increasingly competitive global economy has led to a widespread interest in supply chain (SC) and supply chain management (SCM). The exploding growth of the global economy, driven by the internet, technological innovation, and demand, has evolved the SC into a complex heterogeneous grouping [
1]. SCM has evolved towards globalization, sustainability, and resilience based on the wider domestic and international environment. According to the Council of SCM Professionals, SCM comprises the full range of planned and managed sourcing and procurement, transformation, and logistics management operations [
2]. In addition, it most often involves the coordination of alliances with network partners, which may include suppliers, promoters, external service providers, and customers. In essence, SCM is the co-ordination of the management of supply and demand within and between companies [
2]. While SCM has always been the foundation of business, currently, it is more important than ever as a marker of business success [
3,
4]. In order to live and thrive in the quickly evolving, technologically driven business environment of today, businesses must manage their SCs effectively and adjust as necessary.
The growing awareness of the importance of SCM has generated substantial literature. This literature focuses on how to manage a global supply chain (GSC) (e.g., [
5]), sustainability management of supply chain (e.g., [
6,
7,
8,
9,
10,
11,
12]), closed-loop supply chain (e.g., [
13]), risk management (RM) (e.g., [
14,
15,
16]), and disruption recovery (DR) (e.g., [
17]). Within the research stream of SCM globalization, Koberg and Longoni [
5] provided a comprehensive analysis of the crucial components of sustainable management in GSC. Through a literature review, they identify two key elements of sustainable supply chain management (SSCM) in GSCs: the structural dimension of GSCs, i.e., SSCM configuration, and the relational dimension of GSCs, i.e., SSCM governance mechanisms. In the context of tariffs and price premiums, Chen et al. [
18] analyzed the sourcing decisions of global manufacturers who maintain production sites in a competitive environment and sell their products in domestic and international markets.
There has been a considerable amount of research on SSCM. Silvestre [
4] explored how SC sustainability can be implemented and managed in a developing and emerging economic environment. The paper argues that SCs in developing and emerging economies face additional sustainability challenges due to institutional weaknesses and highly variable business environments, which increase the level of complexity and uncertainty. Farooque et al. [
6] classified terms related to SC sustainability and provided a unified definition of SC sustainability management. Jia et al. [
7] reviewed 55 articles published between 2000 and 2019, identifying four themes in soy SSCM: drivers, global value chain management, consequences, and potential barriers. Nilsson and Goransson [
8] identified, categorized, and evaluated the importance of key factors in achieving SSC innovation through a systematic review and analysis of the relevant sustainable supply chain (SSC) innovation literature. Calmon et al. [
9] analyzed sustainable business strategies for innovative durable goods distributors serving customers in the supply chain, including pricing issues and distribution issues.
Risk management plays a critical role in the effective operation of SCs under various uncertainties. Numerous scholars have contributed to defining, operationalizing, and mitigating risks and SC disruptions brought on by risks over the years by concentrating on supply chain risk management (SCRM) [
14]. Ho et al. [
14] provided a new definition of SC risk and SCRM and proposed five common risks present in SCs based on a review and synthesis of 224 papers published in SCRM from 2003 to 2013, including macro risk, demand risk, manufacturing risk, supply risk, and infrastructure risk. Ivanov et al. [
17] addressed different disruption risks and recovery measures, and the research streams of different quantitative methods and application areas are structured and classified. Behzadi et al. [
15] conducted a comprehensive review of the literature on the agricultural SCRM model, identifying robustness and resilience as two key techniques for managing risk. Huang et al. [
19] provided an in-depth look at how downstream purchasers work with upstream suppliers to improve accountability and reduce risk.
The COVID-19 outbreak has increased SC uncertainty for companies. Due to the dynamic and imprecise nature of COVID-19 growth, there are not enough data to adequately estimate the probability distribution of the unknown parameters [
20]. In order to better cope with emergencies, companies need to grasp SC uncertainty and implement supply chain resilience management to enhance SC resilience. Abouee-Mehrizi et al. [
21] considered the data-driven inventory management of a single, periodically reviewed perishable product (e.g., platelets) with zero lead time and random demand under unit residual shelf-life uncertainty. Li and Mizuno [
22] studied the problem of cycle review, joint dynamic pricing, and inventory in a dual-channel SC where demand is stochastic, and price is sensitive. Niu et al. [
23] examined the manufacturing or purchasing decisions of retailers under uncertain production quantities. Niu and Shen [
24] proposed a programmatic model of two competing SCs to examine the question of whether manufacturers would invest in process innovation considering knowledge spillovers, absorptive capacity, and innovation uncertainty. Saberi et al. [
25] modeled the interaction between firms in a heterogeneous SC under uncertainty in the price of carbon permits and carbon demand. Zhao et al. [
26] investigated the recovery strategies of SC firms under uncertain demand.
In recent years, various studies have been conducted that combine different theories and methods in various areas of SCM for a systematic review. For example, quantitative method combined with empirical study [
17] and structural equation modeling [
27]. Guo and He [
28] argued that game modeling is the most common method used in research to achieve supply chain optimization of platform services. Global supply chains face serious challenges, and uncertainties are widespread in the supply chain management process. Conventional optimization models assume that the input data are accurate, but this approach does not take into account the quality and feasibility of the model as affected by data uncertainty. In reality, the uncertainty of the parameters may affect the feasibility of the resulting solution, rendering the optimal solution meaningless in practice. However, if the effect of uncertain parameters is over-considered, the decision will often result in the decision-maker not obtaining a satisfactory value of the objective function. Therefore, the decision-maker wants to find a solution that is optimal without the influence of uncertainty parameters. In order to provide a more reasonable and accurate description of the uncertainty problem, uncertainty optimization is gradually gaining attention in the academic community. The research on SCM on the basis of uncertainty analysis and optimization modeling (UAO) is of great importance due to the different levels of uncertainty that are faced. Therefore, a review of published articles about SCM using the method of UAO is necessary to provide a comprehensive perspective for the next generation of applying UAO to the study of SCM. In this review study, we provide a systematic review and classification of articles published between 2015 and 2022 that consider UAO in the field of SCM research. Research publications prior to 2015 are excluded from this review because we aim to provide a new overview of recent trends related to the above-mentioned scope of research, and there are fewer articles that combine uncertainty and supply chain management for research prior to 2015. In addition, 2015 saw an increase in adverse factors and uncertainties in world economic performance following the low growth of world industrial production, the continued downturn in trade, and the increased turbulence in financial markets.
Most of the current literature reviewed in the most relevant fields combines supply chain risk management or a specific type of supply chain with uncertainty, and less of the literature has reviewed the uncertainty as well as its solutions in each segment of supply chain management from the perspective of the whole supply chain management. The purpose of this study is to present the application of UAO in SCM and the outlook of its future application direction in the field of the supply chain. This paper bridges this research gap and reviews the literature on optimization modeling as a method to solve uncertainty problems in supply chain management. This study attempts to address the following questions: (1) What are the main uncertainties in supply chain management? (2) What is the status of previous literature on the use of optimization modeling to solve uncertainty in supply chain management? (3) How are the three types of uncertainty methods applied in different areas of the supply chain?
Figure 1 illustrates the research framework of this paper. In terms of analysis, this study carefully and systematically searched research papers involving UAO in SC published from 2015 to 2022, categorized and summarized them for analysis, and then assessed the future research potential of UAO. The top dashed boxes denote the research methodology, while the three solid boxes in the center, linked by thick black arrows, represent the primary research content at various stages.
The rest of the article is organized as follows. In
Section 2, we present the theory of UAO and its development. The literature search process and the research analysis methods used in this paper are briefly summarized in
Section 3. In
Section 4 and
Section 5, all selected articles are summarized and reviewed according to different criteria.
Section 6 and
Section 7 describe the research findings, conclusions, future directions, and limitations.
2. The Evolution of Uncertainty Analysis and Optimization Modeling
As the intersection of combinatorial optimization and uncertainty theory, uncertain network optimization problems have been a hot topic of research. The shortest route problem, minimum spanning tree problem, and other common network optimization issues come in a wide variety. Numerous researchers have been motivated to model network optimization issues mathematically by these appealing challenges [
29,
30]. When the sample size is too small or when there is no population for calculating a probability distribution, we must enlist the assistance of subject-matter experts in order to determine their level of confidence that each event will occur [
31]. Although the probability is one of the theories most commonly used by scholars and practitioners to model uncertainty and subsequently explore the principles inherent in random occurrences, it may not be adequate to address all types of uncertainty associated with unique human beliefs. However, it may not be adequate for addressing virtually all types of uncertainty, especially those associated with unique human beliefs, as it may lead to counterintuitive results [
32]. In order to distinguish it from randomness, this phenomenon is called uncertainty [
33]. To better deal with this uncertainty, Liu [
34] proposed uncertainty theory, which thus became a branch of mathematics to model uncertainty through trustworthiness. Zhou et al. [
35] analyzed a review of 1004 journal papers in the field of uncertainty from 2008 to 2019 to derive seven key sub-fields of uncertainty theory and their research potential. The study finds a linear growth trend in the literature of uncertainty theory, involving an extensive network of 1000 scholars published in 300 journals worldwide, indicating the growing attractiveness of uncertainty theory and its gradual expansion of academic influence.
Mathematical models typically explain engineering problems, and in order to solve these models, it is often assumed that the parameters in the mathematical models are deterministic. However, in practical applications, many parameters are difficult to obtain accurately, leading to uncertainty in the parameters. The response of the theoretical analysis may differ considerably from the actual situation because of uncertain parameters. Consideration of uncertainty in design optimization enhances the design solution’s dependability and durability. UAO can be dated back to the 1950s [
36,
37], and research in this area has proliferated since then [
38].
Based on different theories, uncertainty methods can be classified into three categories, as follows:
(1) Uncertainty programming based on probability theory. Probability theory, a branch of mathematics, deals with the analysis of random phenomena. A random phenomenon is such an objective phenomenon that when one observes it, the result obtained cannot be predetermined, but is only one of many possible outcomes. The outcome of a random event cannot be determined before it occurs. However, it may be any one of several possible outcomes. The actual outcome is considered to be determined by chance. The keyword for uncertainty programming based on probability theory is random.
(2) Uncertainty programming based on fuzzy set theory. Fuzzy set theory is a research method that deals with problems related to fuzzy, subjective, and imprecise judgments, which quantifies linguistic aspects of available data and preferences for individual or group decisions. This method treats the object to be examined and the fuzzy concepts reflecting it as a certain fuzzy set, establishes an appropriate affiliation function, and analyzes the fuzzy object through the relevant operations and transformations of the fuzzy set. Fuzzy set theory is based on fuzzy mathematics to study phenomena related to non-exactness. The keyword for uncertainty programming based on fuzzy set theory is fuzzy.
(3) Uncertainty programming based on uncertainty theory. Expert confidence-based data are concerned with the subjective judgments of different experts about the likelihood of an uncertain event occurring. Such judgments are different from the random sampling studied in classical statistics. Therefore, it is not appropriate to directly adopt the framework of classical statistics for statistical inference. Liu [
34] proposed an uncertainty theory to build a basis for solving the analysis problem of such data. The theory introduces uncertain variables to portray uncertain phenomena by establishing a new axiomatic system, which mainly includes uncertainty measures, uncertain variables and their distributions, and inverse distributions and applications. The keyword of uncertainty planning based on uncertainty theory is uncertain.
The difference between these three uncertainty approaches is that both probability theory and uncertainty theory try to model the degree of human beliefs, the former using possibility measurement tools and the latter using uncertainty measurement tools [
39]. Nevertheless, the fuzzy theory, on the other hand, considers that the degree of belief is a subjective probability or a fuzzy set.
3. Research Methodology
In our retrospective study, combined with the visualization tool CiteSpace and bibliometric analysis, we complete the three main steps of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), including literature search, article eligibility, data extraction, and summarization. CiteSpace presents the structure, patterns, and distribution of scientific knowledge in a visual way, and this software is now widely used to analyze changes in research hotspots and trends. PRISMA is a set of standard specifications established for the quality of systematic reviews and is applicable to analyses of published papers using primary data sources, with the aim of improving the objectivity and consistency of systematic reviews.
3.1. Literature Search
In this phase, we demonstrate the use of UAO in SCM using the well-known database Web of Science (WoS). The database is chosen for several reasons. First, it meets the two core quality criteria for literature databases required in leading literature review approaches, such as those of Tranfield et al. [
40] and Fink [
41]. (1) The scope of the database is consistent with our study design and questions. WoS provides access to over 22,000 journals from all major publishers. This is probably the broadest range of high-quality scientific journals of any database [
42]. In addition, it is one of the most complete and most cited reference databases in the field of supply chain management [
43]. (2) This data is compiled in a database that can be searched in a consistent manner using Boolean operators to construct customized search strings. Thus, we can provide a consistent set of literature covering the topics of supply chain management and uncertainty in the present paper. Second, the database is widely considered to be the standard and most widely used tool for generating citation data for scientific research and other evaluation purposes [
44], and bibliometric studies frequently use the Web of Science as their data source [
45]. Finally, Wang and Waltman [
46] compared the data coverage of WoS, Scopus, and Google Scholar, respectively. The results of the study showed that the journal classification system of WoS is more accurate and, therefore, superior to the other systems. Consistent with Xu et al. [
47] and Saini et al. [
48], the authors rely on WoS because it guarantees standardization, credibility, and high-quality publications and ensures the quality of the analyzed papers. Searching by topic “supply chain management” and “uncertainty”, restricting the paper type to “review literature”, “SCM”, “sustainable SCM”, “supply chain network design (SCND)”, “emergency network optimization”, “logistics network optimization”, “SCN disruption”, and “closed-loop SCM” appear more frequently in the titles. The literature search, therefore, uses these seven keywords (specifically examining the period of COVID-19 when studying supply chain disruption), as well as uncertainty and optimization modeling, to gather the available literature for the period 2015–2022. According to our strategic search, a total of 6591 academic papers are extracted. The following stage is looking for duplicate papers with redundant information, reducing the number to the remaining 275 documents. After that, we exclude irrelevant papers, leaving 153 papers after filtering by title and abstract. We add 18 classic papers for reference, keeping just the final 171 potentially pertinent publications for review (see
Figure 2). In this paper, each article is reviewed according to Amstar entries in the final step of the literature search to determine the final articles used for this review paper.
3.2. Article Eligibility
In order to qualify, we independently review the entire text of each paper that was taken from the previous step in this review process. We carefully select the pertinent items for which consensus has been established in the last step. Literature that considers uncertainty in SCM or has applied UAO is selected, excluding unpublished working papers, editor’s notes, master’s theses, doctoral dissertations, textbooks, and non-English papers. Previous studies considered other approaches to SCM, such as quantitative analysis, so in this step, we also exclude these studies. Finally, we select 121 articles related to UAO methods in SCM that meet the inclusion criteria from 44 international academic journals from 2015 to 2022. We use CiteSpace software to analyze the keyword, and author of the de-duplicated articles, as shown in
Figure 3 and
Figure 4, respectively.
3.3. Data Extraction and Summarizing
A total of 121 papers are reviewed and distilled in the literature as the final step of our methodology. In the subsequent analysis, all chosen articles are classified into different categories, including general SCM, sustainable SCM, SCND, emergency network optimization, logistics network optimization, closed-loop SCM, and SCN disruption during the COVID-19 pandemic period (see
Table 1). In addition, the literature is synthesized and evaluated according to a variety of standards, such as authors’ names, year of publication, application areas, countries, research objectives, modeling methods, research gaps and contributions, research results, and journals in which they appear. Moreover, we consider this review article to be meticulously crafted and a thorough resource on the application of the UAO to SCM. Therefore, we need to go through the article in its entirety and conduct a more in-depth study with more details in order to fully analyze the application of UAO in the field of SCM. Although the selection process is time consuming, it allows us to identify the most appropriate publications.
4. Distribution of Articles by Journal, Year of Publication, and Nationality of Authors
4.1. Distribution of Articles by Journal
The distribution of selected articles by journal is presented in
Table 2. The articles related to UAO and SCM issues are selected from 44 different international academic journals in the Web of Science database. As shown in
Table 2,
Computers & Industrial Engineering and
Journal of Cleaner Production tie for the top ranking with 11 papers among the 44 journals. The finding also indicates that these two journals contribute more to the application of UAO in SCM.
International Journal of Production Research ranks second with 10 papers.
Annals of Operations Research, in addition, ranked third with eight articles. Among the other journal rankings,
Omega, an international journal with seven published papers ranks fourth, and
Soft Computing has six published papers tied for fifth place.
Table 2 demonstrates the distribution of other selected literature.
4.2. Distribution of Articles by Year of Publication
In recent years, the use of UAO in SCM has been increasing. There has been a long-standing historical growth rate of UAO in SCM concerns. Based on the frequency of distribution by year of publication,
Figure 5 depicts the pertinent evidence. The results show that the amount of literature on UAO applications in SCM has increased from 2015 to 2022. The results in this section indicate that 4 articles in 2015 had references to UAO, and 14 articles did so in 2017. In 2018 and 2019, each year had 12 articles on UAO and SCM, a minor decrease from 2017. Starting in 2019, the number of studies on UAO and SCM will increase annually. In addition, the number of papers published between 2020 and 2021 increased from 15 to 30 in one year. This shows that UAO is currently being used by researchers in different areas of SCM and that this number is expected to increase in the coming years.
4.3. Distribution of Papers by Nationality of Authors
We also provide the findings from the analysis of the writers’ nationalities.
Table 3 lists authors using UAO in SCM from 20 different countries, which are shown in
Figure 6. The most published papers are from China (49.18%), followed by Iran (18.03%). The study found that Chinese authors are more interested in research on UAO and SCM, especially in recent years.
5. Publication Areas Classification
Pishvaee et al. [
49] proposed a RO model to deal with the inherent uncertainty of the input data for the CLSCND problem. Initially, a deterministic mixed-integer linear programming model for CLSCND is developed. The robust equivalent of the mixed-integer linear programming model is then demonstrated using the most recent extensions of RO theory. Finally, in order to evaluate the robustness of the solutions derived from the new RO model, they are compared with some implementations of the deterministic mixed integer linear programming model under different test problems. Lalmazloumian et al. [
50] also developed a robust mixed integer linear programming model to study the agile manufacturing firm in a make-to-order production environment for the supply chain planning problem and used a scenario-based RO approach to absorb the effects of uncertain parameters and variables. Shabani and Sowlati [
51] put forward a hybrid multi-stage SO-RO model for maximizing the SC of a forest biomass power plant with uncertainty. Zokaee et al. [
52] addressed the uncertainty in demand, supply capacity, and key cost data. A RO model for SSND is proposed to minimize the total SC cost to determine the optimal siting and allocation strategy.
In this era of black swans, events such as the “car core shortage” and the “shipping shutdown” have overturned many traditional SCM concepts and “uncertainty” has become an element that has to be considered when designing SCs. Uncertainty is not a concept that has only emerged in recent years. The term “VUCA”, i.e., Volatile, Uncertain, Complex, and Ambiguous, which emerged in the 1990s, refers to uncertainty, which has become the norm in SCM due to the high number of unexpected events, high demand for volatility, and high demand for agile response. Klibi et al. [
53] reviewed the optimization models proposed in the literature. They state that the model developed should strike a balance between realism and manageability or solvability, using data available in typical real-world situations.
Today’s world is increasingly characterized by VUCA, i.e., instability, uncertainty, complexity, and ambiguity. The uncertainty faced by SCs is increasing, and SCs are facing more and more unexpected risks, which can easily lead to SC disruptions [
54]. The industry is increasingly concerned with SC safety and security, is committed to dealing with uncertainty in a variety of ways to enhance the SC’s resilience, and has conducted extensive research on this topic using UAO methods. For example, Saghaei et al. [
55] constructed a two-stage stochastic mixed integer nonlinear programming (MINLP) model incorporating opportunity constraints to minimize the total cost of woody biomass power generation in a four-stage integrated bioenergy SC that allows the supply chain to remain resilient in the presence of disruptions. Razavi et al. [
56] modeled the crisis response management phase using a multi-objective mathematical model under conditions of uncertainty. Uncertain data generated under disaster conditions are treated with a RO methodology. In light of this, a hybrid solution method based on a genetic algorithm and multiple-choice objective planning is proposed. Foroozesh et al. [
57] designed new multi-objective mixed-integer linear programming models for multi-product, multi-cycle, multimodal G-elastic SCs by proposing new strategies to minimize the impact of disruptions. Subsequently, using credibility measures and affiliation functions of generalized interval type II fuzzy variables, a new robust possibility planning strategy is suggested to respond with facility supply capacity, customer demand, transportation cost, and CO
2 emission issues.
We grouped and combined articles that considered both UAO and SCM into seven different application areas, including general SCM, sustainable SCM, closed-loop SCM, SCND, emergency network optimization, logistics network optimization, and SCN disruption during the COVID-19 pandemic. In the next sections, all selected articles are summarized and reviewed according to different criteria, including author name, uncertainty conditions, research objectives, modeling methods, research gaps and contributions, and research results.
5.1. Distribution Papers Based on General SCM
In a highly competitive and changing market environment, there are many uncertainties in SCM. In fact, there are three main types of uncertainty in the SC: supply uncertainty, cost uncertainty, and demand uncertainty.
Among the articles in this field selected for this study, Refs. [
27,
58,
59,
60,
61,
62,
63,
64,
65,
66,
67,
68,
69,
70,
71,
72,
73] applied uncertainty methods based on uncertainty theory. For example, Liu et al. [
49,
50] studied the supply risk from suppliers. In their paper published in 2020, they investigated the optimal decision choice of a retailer when the primary supplier faces supply uncertainty, and the output of the alternate supplier is infinite or uncertain [
58]. Subsequently, in 2021, a brand-new idea known as the channel supply risk level (SRL) was put forth to measure the channel supply risk that arises from supply uncertainty [
59]. To explore the impact of environmental uncertainty on decision-makers’ behavior, Farham-Nia and Ghaffari-Hadigheh [
65] described the demand function as a price-dependent, service-dependent, and channel-dependent uncertainty function to investigate the optimal pricing decision for SCs with dual distribution channels in centralized and decentralized decision systems. Ke et al. [
70] proposed uncertainty measures to deal with these artificial degrees of trust and used three uncertainty planning models to derive how channel members should make pricing decisions under three power structures.
Refs. [
74,
75] applied the uncertainty method based on probability theory. Zhao et al. [
74] studied supply chain coordination based on incomplete contracts by using production costs as a random variable. Ma et al. [
75] looked at the distribution of substitutable goods to the same market with a pricing decision dilemma by two risk-sensitive makers in an uncertain environment using a shared dominant and risk-neutral retailer.
Based on the above literature and previous studies,
Table 4 shows the results of the value distribution of UAO based on the authors’ names, uncertainty conditions, research objectives, modeling methods, research gaps and contributions, and research results. The finding in this table indicates that 19 papers applied the UAO method in the general SCM, and most of them used confidence levels for uncertainty analysis and decision modeling. The information for all articles published in the field of general SCM is included in
Table 4.
5.2. Distribution Papers Based on Sustainable SCM
The most common definition of SSCM is the process of managing SCM activities while considering environmental, economic, and social challenges to advance the long-term financial objectives of specific enterprises and their SCs [
76]. Green SCs are closely related to environmental issues in SSC, and many scholars have studied the optimization of Green SCs in an uncertain environment.
Among the articles in this field selected for this study, Refs. [
77,
78,
79,
80,
81,
82,
83,
84,
85] applied uncertainty methods based on uncertainty theory. For example, Shen [
79] studied a two-level Green SC network in an uncertain environment where the market base, customer demand, production cost, and sensitivity to price are assumed to be uncertain variables. A food SSC network that considered the three facets of sustainability (economic, social, and environmental) was designed by Krishnan et al. [
82] using an integrated resilient multi-objective optimization model while considering the perishability of the food SC, the valuing of food waste, and the uncertainty of supply.
Refs. [
85,
86,
87,
88] applied an uncertainty method based on fuzzy set theory. In these, Zhang et al. [
85] focused on social aspects, the effectiveness of relief efforts, and financial costs. For the problem of designing a sustainable last-mile relief network in the face of partial probabilistic uncertainty, a multi-objective distributed RO model is designed. For the pharmaceutical SCND problem in uncertain environments, Zahiri et al. [
86] came up with a new multi-objective integrated sustainable-resilient mixed integer linear programming model.
Refs. [
89,
90,
91] applied uncertainty method based on probability theory. To study the impact of uncertainty on decision variables in SSCs, Shen [
89] developed a multi-objective opportunity constraint model under uncertainty scenarios. Jabbarzadeh et al. [
90] put forward a delayed strategy with the RO model for efficient Green SC planning. Kazancoglu et al. [
91] examined the reactivity of sustainable GSCs during the COVID-19 pandemic while concentrating on the resilience of sustainable (GSCs) to prevent disruptions brought on by epidemics like COVID-19.
For the literature cited above and previous articles,
Table 5 displays the results of the significant distribution of UAO based on author name, uncertainty condition, research purpose, modeling methods, research gap and contribution, and research results. This table reveals that 16 articles utilized the UAO approach in the SSCM.
Table 5 provides additional information on the articles published in the SSCM field.
5.3. Distribution Papers Based on Supply Chain Network Design
SCND is one of the most critical planning problems in SCM. SCND under uncertainty has received considerable attention from both theoretical and practical communities in recent years [
92]. To design SCN under uncertainty, numerical optimization processes based on SC objectives often consider single or multiple objectives. In this section, we address UAO in SCND in terms of mathematical models, solution approaches, and optimization techniques, mainly including SCND problems with continuous stochastic parameters, risk measures in the context of SCND, RO in the context of SCND, fuzzy mathematical planning in SCND environment, and SCND optimization methods with interruptions.
Among the articles in this field selected for this study, Govindan et al. [
92] explored existing optimization techniques for dealing with uncertainty, such as recourse-based stochastic programming, risk-averse stochastic programming, robust optimization, and fuzzy mathematical programming in terms of mathematical modeling and solution approaches.
Refs. [
93,
94,
95,
96,
97,
98] applied uncertainty method based on uncertainty theory. For example, Tirkolaee et al. [
94] attempted to optimally a multilevel blood SC under uncertainty in demand, capacity, and blood disposal rates. Yan and Ji [
96] developed an uncertainty planning model to design a three-level SCN with disruption risk, where disruptions are considered uncertain events. There are also studies that consider both stochastic planning and RO methods.
Refs. [
99,
100,
101,
102,
103,
104,
105,
106] applied uncertainty method based on fuzzy set theory. In these, Salehi et al. [
103] used the optimization approach to design a resilient and sustainable bioenergy supply network based on the uncertainty of bioenergy demand and the disturbance of biorefineries. Yang and Liu [
98] studied the SCND problem under uncertainty, where both customer demand and transportation cost are characterized by fuzzy variables with known likelihood distributions.
Refs. [
107,
108,
109,
110,
111] applied uncertainty method based on probability theory. For the SCND problem under uncertainty, Yang and Liu [
109] constructed a new equilibrium optimization method. The approach uses probability and likelihood distributions to describe the unknown transportation costs and client demand, respectively.
Based on the above discussion,
Table 6 shows the results of the significant distribution of UAO based on author names, uncertainty conditions, research objectives, modeling methods, research gaps and contributions, and research results. The result provided in this table indicates that 21 previous studies used UAO in the area of SCND. The information in
Table 6 pertains to articles published in the field of SCND.
5.4. Distribution Papers Based on Emergency Network Optimization
Emergency SCM is the process of planning and executing the efficient and cost-effective transportation of supplies (including food, water, medicine, etc.) from the place of production to the disaster zone for effective distribution and application to the affected population in the face of disasters and uncertain environments. Emergency SCM is a vital component of the emergency management system for public health emergencies and the prerequisite for constructing a flawless emergency management system.
Among the articles in this field selected for this study, Refs. [
112,
113,
114,
115,
116,
117,
118] applied uncertainty method based on uncertainty theory. For example, Li et al. [
112] employed uncertainty planning methods to deal with the medical material dispatching problem in emergency events. Zhang et al. [
116] investigated the site-routing issue for a sustainable multi-depot emergency facility. Using uncertainty theory, an uncertain multi-objective emergency response site-route planning model that considers travel time, emergency response costs, and CO
2 emissions is developed.
Refs. [
119,
120,
121] applied uncertainty method based on fuzzy set theory. In these, Wang and Sun [
119] established a multi-cycle homogeneous procurement optimization model under uncertainty to obtain optimal emergency supply deployment. Zhu et al. [
121] put forward a collaborative optimization model based on a comprehensive evaluation framework for emergency supply suppliers using interval type-II fuzzy sets for the uncertainty and fuzziness of disaster relief information.
Refs. [
122,
123,
124,
125,
126] applied uncertainty method based on probability theory. Vaezi et al. [
123] investigated the design of emergency networks for railroad hazardous materials transportation under uncertainty and proposed a two-stage stochastic planning model to determine the storage locations of response facilities and equipment packages. Song et al. [
125] investigated the SC operation of rescue equipment in disaster relief under demand uncertainty. The goal is to minimize total and peak delays in product delivery within a multi-period plan.
Based on the above literature and previous papers,
Table 7 provides valuable information about UAO based on the authors’ names, uncertainty conditions, research objectives, modeling methods, research gaps and contributions, and research results. The result of
Table 7 shows that 14 scholars have conducted research on UAO in the field of emergency network optimization in the past.
Table 7 provides some highlights of published research in the area of emergency network optimization.
5.5. Distribution Papers Based on Logistics Network Optimization
Logistics network optimization plays a crucial role in modern logistics planning and SCND [
127]. Logistics managers may greatly increase the effectiveness of the overall freight transportation system and more effectively and promptly meet the needs of their clients with the help of well-designed transportation and logistics networks. Many scholars have studied issues related to logistics network optimization, including sustainable logistics network design issues, RL network design, collaborative logistics network design], and transportation problems.
Among the articles in this field selected for this study, Refs. [
128,
129,
130,
131,
132,
133] applied uncertainty method based on uncertainty theory. For example, Govindan and Golizadeh [
128] studied the robust network design of a sustainable, resilient RL network based on big data using end-of-life vehicles as an example. Chen et al. [
131] examined a class of uncertain two-particle solid transportation problems, where supply demand, transportation capacity, transportation cost, and transportation time are considered uncertain variables. Based on the two types of methods for ordering uncertain variables, an expectation value objective planning model and an opportunity-constrained objective planning model for the two-particle solids transportation problem are developed, respectively.
Refs. [
134,
135,
136,
137] applied uncertainty method based on fuzzy set theory. In these, a new scenario-based resilient bi-objective optimization model for logistics networks was developed by Sun et al. [
133]. It incorporates the placement of medical facilities, the transfer of casualties, and the distribution of aid materials while taking triage into account. Gupta et al. [
137] explored the multi-objective optimization of a multi-product SCN logistics problem in an intuitionistic fuzzy environment to optimally obtain the best distribution order for products from different sources and destinations.
Refs. [
138,
139,
140,
141,
142] applied uncertainty method based on probability theory. In order to help decision-makers select the best collaborative logistics network design option under uncertainty, Xu et al. [
140] suggested a general two-stage quantitative methodology. Jiang et al. [
141] investigated the problem of designing regional multi-modal logistics networks with CO
2 reduction targets and uncertain demand in the context of urban cluster development.
Based on the above literature and previous papers,
Table 8 shows valuable information about the UAO model based on the authors’ names, uncertainty conditions, research objectives, modeling methods, research gaps and contributions, and research results. The result of
Table 8 shows that 15 papers have studied UAO in the field of logistics network optimization in the past.
Table 8 provides some highlights of the published research in the area of logistics network optimization.
5.6. Distribution Papers Based on Closed-Loop SCM
CLSCM refers to all forward logistics in the SC (e.g., material procurement, production, and distribution) and RL in collecting and disposing of returned (used or unused) products and/or product components to ensure socioeconomic and ecologically sustainable recovery [
143]. In the last decade, CLSCM has attracted considerable attention from industry and academia.
Among the articles in this field selected for this study, Refs. [
144,
145,
146,
147,
148,
149,
150,
151] applied uncertainty method based on uncertainty theory. For example, Goltsos et al. [
144] and Peng et al. [
145] conducted review studies of the literature related to CLSC and uncertainty. Goltsos et al. [
144] conducted a systematic review of the literature in the field of CLSC dynamics in uncertain environments, which investigates how material and information fluxes interact over time in the various supply chain components for remanufacturing. Peng et al. [
145] reviewed earlier research on uncertainty in the fundamental properties of CLSCs, examined the factors that contribute to uncertainty at different stages of production and chose the most effective methods to measure its effects.
Refs. [
152,
153,
154] applied uncertainty method based on fuzzy set theory. In these, Kisomi et al. [
152] built an integrated mathematical planning model based on RO theory to address the uncertain environment in these two problems. Considering global factors such as exchange rates and tariffs, Amin and Baki [
154] developed a mathematical model of a CLSC. The model is a mixed integer linear programming model with several objectives and uncertain demand. SC integration and supplier selection are two important strategic decision problems in SCM.
Refs. [
155,
156,
157,
158,
159,
160,
161,
162] applied the uncertainty method based on probability theory. Gholizadeh et al. [
156] studied a multi-layered CLSC for a disposable appliance recycling network, using discrete stochastic situations with uncertainty in demand and cost parameters. Dutta et al. [
160] constructed a recycling framework using buy-back offers at the retailer level. For the purpose of helping to meet the minimum recycling requirements established by legislators and reduce the overall cost of the integrated system, the suggested recycling framework is combined with a multi-period CLSC optimization model with uncertain demand and capacity to determine the best recycling price to offer to consumers.
Based on the above statements about the field of CLSCM,
Table 9 provides valuable information about the UAO method based on the authors’ names, uncertainty conditions, research objectives, modeling methods, research gaps and contributions, and research results. The result of
Table 9 demonstrates that 19 scholars have applied UAO in CLSCM research in the past. Some of the key points from the published studies in the area of CLSCM are presented in
Table 9.
5.7. Distribution Papers Based on Supply Chain Network Disruption during the COVID-19 Pandemic
Public emergencies have a significant impact on SCs, and the COVID-19 pandemic led to a huge impact and influence on economic trade in countries around the world. The issue of SC disruptions once again became a global concern. Scholars have studied SC disruptions in the context of the epidemic, and extensive research has been conducted into coping strategies for SCs.
Among the articles in this field selected for this study, Refs. [
163,
164,
165,
166,
167,
168,
169,
170,
171,
172] applied uncertainty methods based on uncertainty theory. For example, in a two-supplier-one-retailer SC setting, Gupta et al. [
164] studied the impact of supply capacity disruption times on pricing decisions for alternative products. They derived optimal pricing strategies and order levels that considered both disruption times and product substitution. Rahman et al. [
170] examined a consistent set of strategies and recovery plans to minimize costs and maximize the availability of necessary items to cope with GSC disruptions.
Ref. [
173] applied an uncertainty method based on fuzzy set theory. In order to observe the elasticity of economic sectors and rank them using three predefined categories, Kan et al. [
173] proposed using a new fuzzy method, VIKORSort.
Refs. [
174,
175,
176,
177,
178,
179,
180] applied uncertainty methods based on probability theory. A two-layer optimization model was created by Timonina-Farkas et al. [
174] that took demand uncertainty and production disruptions into account. This model took into account how opportunity limitations and dual probability service level demand affected the connection between demand distribution and production disruptions. Optimization models that consider production uncertainty and enable the identification of elasticity strategies are essential to mitigate SC disruptions. Liu et al. [
176] investigated a new disruption propagation management problem for a multilevel SC with a limited intervention budget. The goal was to reduce the risk of interruption as determined by the SC’s target participants’ likelihood of disturbance.
Based on current literature and previously published articles on SCN disruption during COVID-19,
Table 10 shows the significant distribution of authors’ names, uncertainty conditions, research objectives, modeling method, research gaps and contributions, and UAO of research results. As can be observed from the table, 18 scholars have applied the UAO approach in the past in their studies of SCN disruption during the COVID-19 pandemic.
Table 10 provides some highlights of published research in the area of SCN disruption during the COVID-19 pandemic.
6. Findings and Discussions
Our findings show that UAO is an effective decision-making tool when faced with SCM uncertainties, such as uncertainty in demand and uncertainty in costs. Combined with the fact that companies often try to make optimal decisions that satisfy as many objectives as possible, the current environment is characterized by a variety of uncertainties. The UAO approach is frequently utilized in SCM because it can easily handle multi-objective function problems with unclear parameters, which is undoubtedly an appealing characteristic for most researchers. The UAO approach is used to find the best solution when complexity and uncertainty are present. Once the ideal answer has been found, it is converted into suggestions for management decisions.
In addition, the main sources of uncertainty in SCM are supply and demand uncertainty, cost uncertainty, and supply chain disruption risk, and decision-makers often need to make optimal decisions under these uncertainties. According to the results of this review, UAO frequently models the decision problem abstractly before utilizing the appropriate optimization techniques to solve it. This practice is carried out in order to produce scientific decision results in the field of decision-making in SCM. Among the three methods of uncertainty modeling for an optimal solution, RO is the most widely used in SCM, followed by SO.
The construction of RO models has been proposed in the literature, such as characterizing the risk due to uncertainty with confidence in the uncertainty theory. Therefore, future research can extend the results of these models to study supply chain risk contingency management under unexpected contingencies in order to assess risks more effectively and make optimal decisions more quickly. In addition, the literature has used RO models, multi-objective opportunity constraint models recognized uncertainty modeling paradigms, and multi-objective particle swarm optimization solution methods that can only optimize algorithms to solve decision-making problems in SSC. In the future, the conventional paradigm of uncertainty modeling can be combined with big data and algorithms to study green modern digital intelligence SCM in uncertain environments.
Moreover, transportation problems under uncertainty have been studied in the literature, and the expected value model and chance-constrained programming model have been constructed. Future research can combine these models with transportation-related big data to study the optimal design of logistics networks. The SC disruption problem during the COVID-19 pandemic has also been studied in the literature, and various optimization models have been constructed to enhance SC resilience and mitigate SC disruption. After the SC crisis caused by COVID-19, the EU focused its industrial policy on increasing the SC resilience of industrial chains. We should keep an eye on the latest developments in EU industrial policy, analyze and assess any potential effects on China’s SC and industrial chain, plan appropriate responses, and intensify efforts to build resilient SC and industrial chain policies. Therefore, future research can be conducted in the direction of SC resilience management under the impact of a global epidemic. In addition, the theme of promoting high-quality development should be adopted, and efforts should be made to improve the resilience and safety of industrial chains and SCs, as pointed out in the report of the 20th National Congress. Therefore, an important research direction is also the SC safety management of industrial chains under unexpected emergency events. There is also some literature that utilizes the UAO approach in order to obtain the maximization of SC performance based on economic, environmental, social, and other sustainability indicators. In this regard, similar studies can be conducted to consider maximizing SC performance from different perspectives, while UAO can be applied together with some other complex methods, such as game theory. In addition, uncertainty in the attitudes of SC members toward risk has been studied in the literature. In addition to the uncertainty of the external environment, there is also a large amount of uncertainty in the behavior of SC members, such as overconfidence and risk aversion, so UAO can be applied to study the SCM based on behavioral factors in an uncertain environment.
7. Conclusions and Recommendations
Whether it is due to the increase of uncertainty in the external environment, such as natural disasters, political impact, or major public health events, or the increase of uncertainty in the internal environment, such as product quality, lack of capacity, etc., all lead to the increase of uncertainty in supply chain management, and how to effectively deal with and reduce losses after the occurrence of uncertainty in supply chain management is a key challenge for relevant companies. It is a key challenge for the enterprises concerned to deal with the supply chain management uncertainty effectively and reduce the loss after it occurs. By reviewing the literature on the application of UAO in various areas of supply chain management, we provide scholars and practitioners with understanding, decision ideas and insights and future directions on the effective implementation of UAO in SCM under uncertainty.
We tried to classify these papers into the following seven application areas: general SCM, sustainable SCM, SCND, emergency network optimization, logistics network optimization, CLSCM, and SC disruption during the COVID-19 pandemic. The results show that 19 papers apply the UAO approach to general SCM, and 15 studies used the UAO approach in sustainable SCM. In addition, 20 papers applied the UAO approach in the area of CLSCM. A further result shows that 18 studies of papers related to the UAO approach have been conducted in the area of SC disruptions during the COVID-19 pandemic. In addition, 20, 15 and 15 papers have applied the UAO approach in the areas of SCND, emergency network optimization, and logistics network optimization, respectively. In the above literature, the main sources of uncertainty are as follows: (1) uncertainty in demand due to factors such as fierce market competition and variable consumer demand makes it difficult for supply chain companies to obtain full information about the market demand, (2) supply-side uncertainty due to uncertainty in supplier supply quality, quantity, and extended delivery time, and (3) operating cost uncertainty, risk uncertainty, and disruption uncertainty are caused by various internal and external environmental factors. This study only addresses the literature that uses the UAO method for the management of different SCs and different aspects of SCM. Therefore, other methods can be considered for further research in the application of SCM.
In terms of journal distribution, Computers & Industrial Engineering and Journal of Cleaner Production tie for first place with 11 articles, and Annals of Operations Research ranks third with nine articles related to UAO methodology and SCM. In terms of ethnicity-based classification, there are 20 ethnicities and countries applying the UAO approach to SCM issues. Finally, among SCM, Chinese scholars published the most contributions of UAO-related papers, followed by Iran.
The findings of the study indicate that the UAO method is appropriate for resolving uncertainty in SCM. By merging the academic literature on SCM under uncertainty and reviewing the outcomes of UAO research in many application domains, we obtain a better knowledge of both the specific results and the solution to uncertainty problems in SCM. These results are intended to contribute to SCM and UAO literature and to assist academic researchers and managers in SCM areas where uncertainty exists to make optimal decisions in SCM through modeling and optimal resolution of uncertainty.
The theoretical contributions of this paper are to complement the existing literature by demonstrating the application of the UAO approach to SCM and to validate the applicability and importance of the uncertainty model optimization approach in the field of supply chain management. By summarizing the application of UAO in the seven areas of supply chain management subdivided in this paper, an overview of UAO research in these areas is derived, with relatively more research applying UAO methods in the areas of general SCM, CLSCM, and SCND. Many unexpected events, high demand volatility, and high demand for agile response have become the norm in supply chain management. Supply chain uncertainty optimization enables supply chains to operate as planned. The practical contributions of this paper are to provide a reference for researchers in this research direction of uncertainty and supply chain management in the future by reviewing the literature on the use of uncertainty optimization models to solve uncertainty problems in supply chain management, which in turn enlightens decision-makers to better solve a series of uncertainty problems in SCM, improve the efficiency of decision-making, and keep the supply chain stable.
Like with any study, this article contains some limitations that can be considered in future investigations. These limitations can provide opportunities and suggestions for future research. First, this study divided the 121 articles into seven application areas. We recommend that future research reviews papers in different subfields of these categories. Second, this paper reviews the application of UAO in various areas of SCM and identifies the most used UAO and its solution methods for SCM uncertainty problem solving, mainly the three more traditional optimization modeling solution paradigms of SO, chance constraint, and RO. In this regard, it is recommended that other number-wise techniques be used in future research for modeling solution optimization analysis of uncertainty problems in SCM. Third, the data were collected from journals, and the literature does not include textbooks, PhD and MSc theses and dissertations, or unpublished papers on UAO methods and SCM. As a result, information for future studies can be gathered from these sources, and the results can then be compared with the findings and reports of previous research. Fourth, the paper presents the selection and summary of articles by different publishers in the Web of Science. However, it is possible that some of the relevant outlets are still outside the scope of this study. Therefore, the evaluation of papers that were not part of the present study should be the subject of future research. Fifth, this research reviews numerous journal articles that describe the use of the UAO methodology to supply management concerns. Nevertheless, this review does not include recently published book-length approaches. Finally, this paper classifies papers based on seven different areas of SCM rather than different uncertainty analysis modeling optimization solution methods, so the classification of papers based on the UAO approach needs further study.