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In this paper, a blood supply chain network (BSCN) is designed to reduce the total cost of the supply chain network under demand and transportation costs. The network levels considered for modeling include blood donation clusters, permanent and temporary blood transfusion centers, major laboratory centers and blood supply points. Other goals included determining the optimal number and location of potential facilities, optimal allocation of the flow of goods between the selected facilities and determining the most suitable transport route to distribute the goods to customer areas in uncertainty conditions. This study addresses the issue of blood prishability from blood sampling to distribution to customer demand areas. Given that the model was NP-hard, the MFGO algorithm were used to solve the model with a priority-based solution. The results of the design of the experiments showed the high efficiency of the MFGO algorithm in comparison with the PSO algorithm in finding efficient solutions. Also, the mean of the objective function in robust approach is more than the one in the deterministic approach, while the standard deviation of the first objective function in the robust approach is less than the one in the deterministic approach at all levels of the uncertainty factor.

The vibrant subject of blood banking and blood distribution is addressed where lateral resupply of blood products is allowed. In this paper, we studied a blood supply chain network design consisting of four conventional levels each of which corresponding to one entity in the real world: donors, blood collection facilities, blood centers, and hospitals. The blood supply chain network considered two important properties: ABO-Rh factors and shelf lives of blood products. Moreover, an integrated inventory system for sharing hospitals’ inventory levels is considered to investigate the two performance indicators of the network in terms of cross-matching and outdated units. This type of inventory system is known as “Lateral Resupply” permitting a hospital to satisfy its demand by the other hospitals’ inventories in the absence of the required product at the blood center and its excess in any hospital. The proposed mixed-integer mathematical programming model entails three objectives referring to the three underlying concepts of sustainability, additionally, to cope with uncertainties and multi objectiveness, a scenario-based optimization approach and revised multi-choice goal programming technique were employed, respectively. Finally, the results confirmed that the lateral resupply virtue improved the performance indicators.

Primitive chain network simulations for randomly cross-linked slip-link networks were performed. For the percolated networks, the stress-strain relationship was compared to the theories by Ball et al. [Polymer, 22, 1010 (1981)] and Rubinstein and Panyukov [Macromolecules, 35, 6670 (2002)]. The simulation results were reasonably reproduced by both theories, given that the contributions from cross-links and slip-links were used as fitting parameters. However, these parameters were model dependent. Besides, the theories cannot describe the simulation results if the parameters were determined from the number of active links involved in the percolated networks. These results reveal that the fitting of experimental data to the theories does not provide a fraction of entanglements in the system unless the network only consists of Gaussian strands and it correctly reaches the state of free-energy minimum., Comment: 20 pages, 6 figures

Birefringence measurement demonstrates that the segment orientation of entangled polymers overshoots on start-up of fast shear [Pearson et al. J. Rheol. 1989 33, 517–535]. The stress-optical rule holds for those polymers, so that the overshoot of orientation results in the overshoot of shear stress. On the other hand, an opposite result was deduced from the recent molecular dynamics simulation for bead–spring chain [Lu et al. ACS Macro Lett. 2014 3, 569–573]: the evolution of segment orientation does not overshoot but the chain stretch induces the stress overshoot, even at the shear rate γ smaller than the reciprocal Rouse time, 1/τR. In this study, we performed the primitive chain network simulation to find that our simulation reproduces the overshoot of both stress and orientation and the chain stretch exhibits a slight, monotonic increase but no overshoot. Our result is thus fully consistent with the experiment.

The poly(lactic acid) (PLA)-tricalcium phosphate (TCP) composite attracts much attention as a material for a bone fixation device because both have bioabsorbability. However, the applications of the composite bone fixation device are limited to low-loaded regions because of lower strengths. In this study, PLA and TCP/PLA composite cylindrical billets were extruded to improve their strengths, with the aim of clarifying the molecular orientation behavior of the PLA and TCP/PLA billets in extrusion. First, the effect of the orientation behavior in the PLA billets on the extrusion ratio (ER) was calculated. Next, the TCP/PLA billets were analyzed. The molecular orientation obtained by extrusion was investigated by a combination of the finite element method and the chain network model. Consequently, the orientation function of the extruded billet was found to increase with the ER. Furthermore, the orientation function of the TCP/PLA billet was higher than that of the PLA billet, which may be due to the change in the yield stress and n value of the billet by TCP addition. The orientation distribution in the radius direction of the extruded PLA billet showed that the orientation function at the surface region was larger than that at the center region. This orientation distribution might be because the movement distance of the surface region during extrusion was longer than that in the center region. The surface region in the billet was drawn by the difference of those movement distances and might be orientated. The workability of the PLA and TCP/PLA billets was also investigated using pressure during extrusion. The results showed that the extrusion pressure increased with the TCP content and ER. Therefore, extrusion workability decreased with the TCP content and the ER.

This study examines the effect of the performance of traders in the partnership relationship between the government, the private sector, and the community which is very necessary to build a food supply chain network in order to provide stimulation for the supporting factors and reduce the inhibiting factors for the success of the merchant's business, increase profits, and maintain food availability in traditional markets. This research was conducted at Andir Market, Bandung City, Indonesia. The research sample consisted of 100 Andir market traders. The research method used was a quantitative method with survey research that uses a questionnaire as the main instrument in data collection. The results of the analysis and discussion of the researchers have identified factors that can be used to strengthen the food supply chain network in the Public-Private-Community Partnership in traditional markets, namely management, empowerment, physical market conditions, and competitive strategies. Simultaneously, the four traders' performance factors have a significant effect on the food supply chain network with an R-square value of 0.658 (65.8%) with tcount greater than 1.96 or (3.817> 1.96). This means that if the changes that occur are good in the performance of traders, the food supply chain network in traditional markets will also be good, while the remaining 0.342 (34.2%) is explained by factors other than these variables. The expected implication is that the success of the supply chain network that is built due to strong interactions within the Public-Private-Community Partnership and other supply chain actors is able to face challenges during and after the pandemic. So that the quality of traditional market products, especially products that are quickly damaged or rotten, can be superior and well guaranteed for the food needs of people throughout Indonesia.

In the recent decade, the design of green hydrogen supply chains has been highlighted by researchers. Although, nowadays, responsiveness and social responsibility of networks could also be regarded as important measures that could attract more consumers to use hydrogen. Accordingly, this paper aims to improve the reliability and social responsibility of a hydrogen supply chain along with its economic and environmental aspects. To ensure the network's responsiveness, a new objective function is extended that maximizes the reliability of products' delivery. Also, a novel reliability approach is developed to immune the network against disruptions. As a new sustainability indicator, social factors are considered in the design of the hydrogen supply chain. Finally, a mixed possibilistic flexible programming method is proposed to assure the outputs' reliability. The results illustrate that by 28.4% enhancement in cost objective, the value of environmental, social, and reliability objectives are desirably improved 39.2%, 45.6%, and 24.1%, respectively.

This paper provides an original empirical analysis of the European regional production network, making use of the interregional world input-output database. Similar to the concept of key sectors, a...

This article proposes a novel design of a disaster relief blood supply chain network with multiple echelons and multiple products. It incorporates: (1) the blood donors’ behavior and preference for the selection of facilities where the blood donation takes place, (2) an estimating the quantity of the injured people under each disaster scenario, (3) the inherent uncertainty in input parameters and (4) the remaining capacity for satisfying the demand affected by the disruption in blood facilities (i.e., both blood collection and production centers). To incorporate the utility of blood collection facilities, a utility assessment approach, called Logit model, is developed, which measures the donors’ preference. The disrupted capacity and the number of injured people under each disaster scenario are estimated based on the disaster severity, the distance from the disaster (particularly earthquake) epicenter and the civil infrastructure. The uncertainty of parameters (e.g., cost parameters as well as blood supply and demand) along with the disruption in blood facilities are two unavoidable concerns of disaster relief blood supply chain planning. Accordingly, to handle the parameters under mixed uncertainty, a new approach which is two-stage stochastic-robust is utilized. Finally, using real data of a case study in Iran, the presented formulation and its solution approach are examined. The obtained results demonstrate that the related managers should be aware of blood donors’ behavior, injured people in disaster, and the effect of disruption in the blood supply chain network design. Moreover, when it comes to the uncertainty of parameters, the obtained results from the robust model overcome those of deterministic one. Finally, based on findings, applicable managerial insights are derived for the decision-makers in blood supply chain network design for disaster relief cases.

The non-linear viscoelastic response under interrupted shear flows is one of the interesting characteristics of entangled polymers. In particular, the stress overshoot in the resumed shear has been discussed concerning the recovery of the entanglement network in some studies. In this study, we performed multichain slip-link simulations to observe the molecular structure of an entangled polymer melt. After confirming the reasonable reproducibility of our simulation with the literature data, we analyzed the molecular characteristics following the decoupling approximation. We reasonably found that the segment orientation dominates the stress overshoot even under the resumed shear with minor contributions from the segment stretch and entanglement density. We defined the mitigation function for the recovery of the stress overshoot as a function of the rest time and compared it with the relaxation of the molecular quantities after the initial shear. As a result, we have found that the mitigation of the stress overshoot coincides with the relaxation of entanglement density., ファイル公開：2021/07/28

This study is based on a real-life case study of a SCND of a single milk product (premium milk) of a leading milk producing organization in Odisha. This product is highly perishable in nature; SCND implicates decision-making at a strategic level. Network design is the basis for the efficient operation of supply chain, and consequently, one of the most important problems a supply chain manager has to solve. This study conducts a real-life case-based modeling to address the gap in the area of supply chain network design. The author investigates the milk supply chain network design under preservation technology and propose a generic mathematical model for milk supply chain network design encompassing economic objective. A customized mathematical model is also developed for a leading milk producing organization in Odisha. Both of the models are formulated and solved by using piecewise nonlinear optimization.

Viscoelastic (VE) dampers are one of the most promising techniques for reducing vibration in engineering structures caused by earthquakes and wind. This work aims to develop a kind of high-...

Blockchain is an innovation developed to encourage money exchange transactions and take out the requirement for a trusted third party to legally approve and confirm such exchanges to ensure information security and protection. New structures of blockchains have been intended to suit the requirement for this technology in different fields, for example, e-health, the travel industry, and energy. This chapter is concerned about the utilization of blockchains in overseeing and sharing electronic health and medical records to permit patients, emergency clinics, centers, and other stakeholders to share information among themselves and increment interoperability. The choice of the design of the blockchains utilized relies upon the elements chipping in the constructed chain network. In spite of the fact that the utilization of blockchains may decrease redundancy and give guardians reliable records about their patients, it accompanies a few difficulties, which could encroach patients’ security or possibly bargain the entire system of partners. In this chapter, we examine distinctive blockchain structures through various sections like blockchain in healthcare today, how it is changing the future of healthcare, and the benefits of blockchain. The chapter also deals with the implementation and challenges of blockchain in healthcare sector.

International audience; 1,1'-Biphenyl-3,3ʹ,4,4ʹ-tetracarboxylic acid dianhydride has been reacted with uranyl nitrate under solvo-hydrothermal conditions and in the presence of different counterions to give three complexes of varying periodicity. [Co(en) 3 ][UO 2 (bptc)(HCOO)]⋅2.5H 2 O ( 1 ) crystallizes as a monoperiodic coordination polymer in which the bptc 4– ligand is exclusively bound through formation of two 7-membered chelate rings. The [Co(en) 3 ] 3+ counterion is essentially a hydrogen bond donor, forming 15 hydrogen bonds with carboxylate and water oxygen atoms. In [H 2 NMe 2 ] 2 [UO 2 (bptc)]⋅0.5H 2 O ( 2 ), half the ligand forms a 7-membered chelate ring, and the other half bridges two uranium atoms, resulting in the formation of a diperiodic network with hcb topology, the H 2 NMe 2 + counterions being located between the undulating sheets. [PPh 4 ] 4 [(UO 2 ) 4 (bptc) 3 ]⋅6H 2 O ( 3 ) contains a mixture of ligands forming either four 4-membered or two 7-membered chelate rings, the latter with further bridging, which gives a triperiodic framework displaying large channels, each of which contains two rows of PPh 4 + counterions. These results are compared to those of previous studies with this ligand, and of similar studies of phthalate complexes of uranyl ion, in particular in relation to 7-membered chelate ring formation.

One of the most devastating events is earthquake. Along with planning for supply and the proper distribution of relief goods including food and cloths, one of the most vital issues is to relieve to injured people who are in need of blood. In this research, we design a blood supply chain when the earthquake takes place, should the need arises by people requesting the blood units. Based on this need, a multi-level multi-objective mathematical model is designed during several periods based on minimizing the cost of the blood supply chain network and maximizing the reliability of the selectable paths for blood transportation. This model determines the optimal number and locations for establishing the facilities as well as determining the allocation of blood to various facilities, and, on the other hand, optimal routes for blood transportation among facilities. The mathematical model presented is validated by data acquired from implemented model of Tehran city.

Poly(lactic acid) (PLA) has attracted much attention for use in bone fixation devices, which are used for fracture treatment, because it degrades to nontoxic lactic acid through nonenzymatic hydrolytic degradation. However, the application of such device is limited to relatively low-load regions, because mechanical properties of PLA is poor than that of metal materials. The process of drawing PLA fibers has attracted much attention as an approach for improving the mechanical properties of PLA bone fixation devices. The mechanical properties and molecular orientation of drawn PLA fibers and films have been investigated. However, the optimization of drawing conditions in bulk processes in relation to bone fixation devices is difficult because a large number of potential drawing conditions exist. The purpose of this study was to analytically clarify molecular orientation behavior in drawn PLA billets. The molecular orientation obtained by extrusion in PLA billets was investigated using a combination of the finite element method (FEM) and a chain network model. As a result of the FEM, first principal plastic strain was generated, mainly in the tapered components during extrusion; this strain was in the axial direction of the rod. Radius strain distributions showed that strain in the center region was almost uniform, whereas strain peaked near the surface. The orientation function increased with extrusion ratio (ER), and the peak orientation function in the surface region increased with taper angle. Thus, the magnitude and distribution of the orientation function in extruded PLA billets may be controllable by ER and taper angle, respectively.

Soybean is one of the primary commodities of food after rice and corn. Soybean in Indonesia is one of the strategic food crops. The problem of local soybean supply chain compared to the important soybean chain is the supply of local soybeans involving many parties in soybeans. The number of distribution channels for the supply of local soybeans is also a trend for changes in price variations. More effective than efficient and efficient supply chains in local soybeans. The objectives of this study are (1) to identify conditions and protection in the soybean supply chain; (2) Analyzing the performance of the soybean agroindustry supply chain. To analyze the investment supply chain using the Food Supply Chain Network (FSCN), SCOR-AHP is used to analyze supply chain performance. The structure of soybean agroindustry supply chain in Cianjur Regency involves farmer, breeder, collector, Indonesian Tofu and Tempe Producers Cooperatives (KOPTI), agro-industry, local traders and inter-regional traders. The results of the calculation of the valuation of the market at the farmer level are 85,325%, traders are 92,926%, and agroindustry is 87,004%.

The fundamental way to reduce the risk of bird strike is to manage the ecological environment of the airport and its surrounding areas and affect the ecological chain of birds. Based on a comprehensive survey of animal and plant populations in Meizhou airport, an airport ecological chain network is established, and a improved cascading failure model in coupled map lattices is introduced to simulate the robustness and vulnerability of the network. It is found that airport ecological network will be collapsed around five time series one after another under the external attack. It also shows that the network will have a global breakdown under a very small external perturbation value when Solanum indicum L. and Callidium villosulum Fairmaire are deliberately attacked. The simulation results show that if the airport authorities give priority to governance these populations of animals and plants with higher in-degree, it may reduce bird strike risk. The analysis results provide a theoretical basis for airport bird strike prevention.

In the present paper, a new type of micro-mechanically motivated chain network model for rubber-like materials is proposed. The model captures topological constraints of polymer network chains, in particular, entanglements. The model demonstrates how the local molecular packing constraints modify under deformation and shows the impact of these changes on the macroscopic elasticity of the material. To this end, we combine concepts of a confining tube and a slip-link (reptation) model. In these models, entanglements of polymer chains play an important role. The nature of entanglements is discussed, and relationships governing entanglements are formulated in terms of molecular physics. In the context of nonlinear elasticity, we apply a non-affine concept which captures the liquid-like behavior of polymer networks at smaller scales in a more realistic way. Model predictions show good agreement with experimental results from uniaxial and biaxial tension tests.

Inspired by inorganic oligomers and their polymerization, we herein develop a heterogeneous inorganic polymerization tactic that can be used to prepare a muscle-like hybrid hydrogel by inducing the polymerization of calcium phosphate oligomers (CPO) onto a polyvinyl alcohol (PVA) molecular chain network. In this heterogeneous process, the CPO units bond with PVA molecules via assistance from sodium alginate (SA), and then gradually polymerize along the organic chains to form ultrafine hydroxyapatite nanolines with a diameter of ∼1 nm. Because of the well integration of organic and inorganic phases from the heterogeneous polymerization, the hierarchical structured hydrogel can exhibit ultratough mechanical properties of ∼17.84 MPa in strength and ∼8.97 kJ m-2 in fracture energy, which exceed natural muscles and almost synthetic hydrogels. Moreover, the damaged hydrogel can be repaired readily by adding the precursors of CPO, PVA, and SA, which can induce in situ re-polymerization. The hydrogel also exhibits muscle-like rotational motion under aqueous conditions, which can be developed into a water-driven biomimetic motor. This study indicates that inorganic polymerization can achieve a novel organic-inorganic integration rather than conventional organic-inorganic composition, and it provides a novel tactic for design and manufacture of advanced materials.

This paper investigates the synchronization analysis of strict feedback like class of linear and non-linear systems based on contraction principle. Recursive step by step procedure based on contraction theory is used to develop coupling function to establish the synchronization of different systems in one way coupled chain network configuration. Here, systems are considered to be connected through one way coupling function in chain formation. The analytically derived procedure leads to a single control law for stabilization of strict-feedback like class of systems. The same stabilizing control function is used as coupling link to establish a synchronized chain network of N-systems. The proposed approach is verified for effectiveness using linear systems & Genesio chaotic system based network. The numerical simulations demonstrate the efficacy of proposed technique.

The frequency dependence modeling of viscoelastic (VE) materials faces the challenge of high modeling accuracy over a wide frequency range and double-objective optimization in model paramet...