A multi-agent based approach for change management in manufacturing enterprises

Change management becomes an unavoidable necessity for manufacturing enterprises. Since change in business processes carries significant impact on the performance of manufacturing companies, a change management model is definitely required to remain competitive. Moreover, utilizing agent based systems will provide computational provision and integrity to manage and measure the capabilities to follow the change in a progressive approach by employing the cooperation and collaboration properties of various agents helping for retrieval of the required information in a rapid way. Therefore, in this paper, a multi-agent based change management model is proposed to handle the changes in manufacturing enterprises. The model is validated through a case study done to measure the performance of change management capabilities in a manufacturing company. A sensitivity analysis on the results of this case study is also conducted to reveal the system reactivity to various parameters.     

Evaluating fault tolerance approaches in multi-agent systems

A multi-agent system (MAS) is a distributed system that consists of multiple agents working together to solve mutual problems. Even though MASs are well suited for the development of complex distributed systems, the number of real-world usages is still small. One of the main reasons for this is that MASs are very fragile. In a typical, large-scale MAS, the rate of failure grows with the number of hosts, the number of deployed agents, and the duration of the agent’s task execution. For this reason, numerous approaches have been introduced to deal with aspects of failure handling. However, the absence of centralized control and a large number of individual intelligent components makes it difficult to detect and treat errors. The risk of uncontrollable fault propagation is high and can seriously impact on system performance. There are two important factors that limit the usage of MASs: (1) existing fault tolerance (FT) approaches are not generic, as they focus on and improve specific issues of FT; and (2) despite the plethora of available FT approaches and theories, there is a remarkable lack of general metrics, tools, benchmarks, and experimental methods for formal validation and comparison of existing or newly developed FT approaches. As FT approaches in MASs become a well-established field, the need for generalized, standardized evaluation of FT approaches emerges as imperative. In this paper, we first present a detailed overview of existing FT solutions, approaches, and techniques in agent platform hosted MASs. From that overview, we derive the commonalities in existing research. Next, we present the main contribution of our paper: an evaluation methodology, with a set of metrics, for comparing FT approaches in MASs. We adopt an engineering perspective on the problem, defining a methodology and metrics that are both implementation- and domain-independent. The metrics are formalized with an acyclic directed graph. By using our methodology, evaluators can select an appropriate FT approach for targeted MAS application, thus improving MAS usability, stability, and development speed. In order to show the viability of our approach, a case study that compares two FT approaches for a targeted MAS is presented. The case study results show that our methodology can be used for selecting an appropriate FT approach for the targeted MAS.     

A Credit-Based Congestion Management Scheme in General Two-Mode Networks with Multiclass Users

This paper examines the design of the credit-based congestion management schemes that achieve Pareto-improving outcome in general two-mode networks. It is assumed that transit is a slower but cheaper alternative to driving alone. The distributional welfare effects of congestion pricing on users with the different value of time (VOT) in Liu and Nie (Trans Res Board 2283:34–43, 2012) are used in developing Pareto-improving credit schemes. We show that, similar to the single-mode model, the sufficient and necessary condition for the existence of a discriminatory Pareto-improving credit scheme is the reduction in the total system cost. A sufficient condition for the existence of an anonymous Pareto-improving credit scheme is also derived. A cross-OD subsidization scheme is proposed when the sufficient condition is not satisfied for each origin-destination (O-D) pair. Numerical experiments on the expanded Sioux Falls networks with a log-normal VOT distribution demonstrate that the proposed Pareto-improving scheme can generate positive net revenue in the presence of good transit coverage.     

Tocopherols,Tocotrienols and Carotenoids in Kernel Oils Recovered from 15 Apricot (<Emphasis Type="Italic">Prunus armeniaca</Emphasis> L.) Genotypes

We studied the content of tocopherols, tocotrienols and carotenoids in oil extracted from the kernels of 15 apricot (Prunus armeniaca L.) genotypes and the associated oil yield of the studied samples. The oil yield in apricot kernels was in a wide range of 27.2–61.4% (w/w) dry weight basis. For each class of studied compounds (tocochromanols and carotenoids), a three-fold difference was found between the lowest and the highest content (78.8–258.5 and 0.15–0.53 mg/100 g of oil, respectively). γ-Tocopherol accounted for 91–94% of total tocochromanols detected in all tested samples. Lutein, zeaxanthin, β-cryptoxanthin and β-carotene were the main compounds among the eight different carotenoids detected in apricot kernel oils; they comprised 76–94% of the total carotenoids content, and compositions were characteristic for specific genotypes. The oil yield and content of lipophilic antioxidants in apricot kernel oils were significantly affected by the genotype. The oil yield was negatively correlated with the total amount of tocochromanols (r = ?0.910) and carotenoids (r = ?0.704) in apricot kernel oils.     

Biotechnological and Novel Approaches for Designing Structured Lipids Intended for Infant Nutrition

Human milk fat (HMF) is a perfect nutritional source that includes all the required ingredients which are necessary for the growth of infants up to 6 months. Although its composition may differ among mothers or during lactation stage, its unique triacylglycerol (TAG) structure remains constant which is characterized by the presence of palmitic acid (PA) at the sn‐2 position. Previous reports provided convincing information of higher PA and calcium absorption and efficient use of dietary energy when at this specific position in the TAG moiety than when PA is at the sn‐1,3 positions. During the design of structured lipids (SLs) intended for infant nutrition, this unique property is taken into consideration. Human milk fat substitutes (HMFS) enriched with important fatty acids such as omega‐3 and omega‐6 fatty acids are intended to better mimic the functions of HMF as well as provide associated health benefits. The use of microencapsulation technology and novel technologies such as ultrasound technology in conjunction with SL production and enzyme‐catalyzed reactions are evolving and ongoing issues in infant formula production. Therefore, further studies should be directed towards new process improvements in order to increase the functional properties and oxidative stabilities of HMFS. Novel technologies in lipid biotechnology related to HMFS preparation should also be explored.     

EPA,DHA, and Lipoic Acid Differentially Modulate the n-3 Fatty Acid Biosynthetic Pathway in Atlantic Salmon Hepatocytes

The aim of the present study was to investigate how EPA, DHA, and lipoic acid (LA) influence the different metabolic steps in the n‐3 fatty acid (FA) biosynthetic pathway in hepatocytes from Atlantic salmon fed four dietary levels (0, 0.5, 1.0 and 2.0%) of EPA, DHA or a 1:1 mixture of these FA. The hepatocytes were incubated with [1‐¹⁴C] 18:3n‐3 in the presence or absence of LA (0.2 mM). Increased endogenous levels of EPA and/or DHA and LA exposure both led to similar responses in cells with reduced desaturation and elongation of [1‐¹⁴C] 18:3n‐3 to 18:4n‐3, 20:4n‐3, and EPA, in agreement with reduced expression of the Δ6 desaturase gene involved in the first step of conversion. DHA production, on the other hand, was maintained even in groups with high endogenous levels of DHA, possibly due to a more complex regulation of this last step in the n‐3 metabolic pathway. Inhibition of the Δ6 desaturase pathway led to increased direct elongation to 20:3n‐3 by both DHA and LA. Possibly the route by 20:3n‐3 and then Δ8 desaturation to 20:4n‐3, bypassing the first Δ6 desaturase step, can partly explain the maintained or even increased levels of DHA production. LA increased DHA production in the phospholipid fraction of hepatocytes isolated from fish fed 0 and 0.5% EPA and/or DHA, indicating that LA has the potential to further increase the production of this health‐beneficial FA in fish fed diets with low levels of EPA and/or DHA.     

Yield,nitrogen recovery efficiency and quality of vegetables grown with organic waste-derived fertilisers

More sustainable production of high-quality, nutritious food is of worldwide interest. Increasing nutrient recycling into food systems is a step in this direction. The objective of the present study was to determine nitrogen (N) fertiliser effects of four waste-derived and organic materials in a cropping sequence of broccoli, potato and lettuce grown at two latitudes (58° and 67°N) in Norway during 3 years. Effects of anaerobically digested food waste (AD), shrimp shell (SS), algae meal (AM) and sheep manure (SM) at different N application rates (80 and 170 kg N ha^?1 for broccoli, and 80 and 60 kg N ha^?1 for potato and lettuce, respectively) and residual effects were tested on crop yield, N uptake, N recovery efficiency (NRE), N balance, N content in produce, mineral N in soil, product quality parameters and content of nitrate in lettuce. Mineral fertiliser (MF) served as control. Effects on yield, N uptake, NRE, N balance and product quality parameters could to a great extent be explained by estimated potentially plant-available N, which ranked in the order of AD > SS > SM > AM. Results for crops fertilised with AD and SS were not significantly different from MF at the same N application rate, while AM, in agreement with its negative effect on N mineralisation, gave negative or near-neutral effects compared to the control. No residual effect was detected after the year of application. The results showed that knowledge about N dynamics of relevant organic waste-derived fertilisers is necessary to decide on the timing and rate of application.     

Assessment of dietary and genetic factors influencing serum and adipose fatty acid composition in obese female identical twins

Fourteen pairs of obese female monozygotic twins were recruited for a study of genetic influences on serum and adipose fatty acid (FA) composition. Following 1 wk of inpatient stabilization, fasting serum and adipose tissue obtained by surgical excision were analyzed by thin-layer and gas chromatography. Intrapair resemblances (IPR) for individual FA were assessed by Spearman rank correlation and by analysis of variance and were found in serum cholesteryl esters (CE), triglycerides (TG), and adipose TG. With two exceptions (CE linoleate and adipose eicosapentaenoate), these IPR were limited to the nonessential FA. Palmitate had significant IPR in four lipid fractions; in serum CE and adipose TG palmitate was strongly correlated with multiple measures of adiposity. In contrast to other lipid fractions, serum phosphatidylcholine (PC) FA had 12 IPR, of which 6 were essential FA including arachidonate (r=0.76, P<0.0005), eicosapentaenoate (r=0.78, P<0.0005), and docosahexaenoate (r=0.86, P<0.0001). The PC IPR could not be explained by analysis of preadmission 7-d food records. After dividing the pairs into two groups differing and nondiffering according to fat intake of individuals in the pair, there was no evidence of a gene-environment interaction between fat intake and FA composition. The IPR for nonessential FA indicate that there is active genetic control of either food choices or postabsorptive metabolic processing. The high level of IPR in the PC fraction in contrast to the other lipid fractions suggests strong genetic influence over selection of specific FA for this membrane fraction independent of diet.     

广东省水利数据中心数据资源化研究及应用

物联网等信息技术的发展,极大地丰富了水利行业的数据资源。如何对数据资源进行标准化操作,实现资源共享条件下水利业务应用协同的目标,是当前水利行业亟待解决的重要问题之一。结合广东省水利数据中心数据资源化建设与实践,讨论了当前水利数据资源化建设存在的主要问题,从六个方面阐述了广东省水利数据中心数据资源化建设的实践。