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141.
In this paper, a single-item capacitated lot-sizing problem in a flow-shop system with energy consideration is studied. The planning horizon is defined by a set of periods where each one is characterised by a length, an allowed maximal power, an electricity price, a power price and a demand. The objective is to determine the quantities to be produced by each machine at each period while minimising the production cost in terms of electrical, inventory, set-up and power required costs. For medium- and large-scale problems, lot-sizing problems are hard to solve. Therefore, in this study, two heuristics are developed to solve this problem in a reasonable time. To evaluate the performances of these heuristics, computational experiments are presented and numerical results are discussed and analysed. 相似文献
142.
Xiaofang Jia Kosuke Minami Koichiro Uto Alice Chinghsuan Chang Jonathan P. Hill Jun Nakanishi Katsuhiko Ariga 《Advanced materials (Deerfield Beach, Fla.)》2020,32(4):1905942
There is a growing interest in the development of dynamic adaptive biomaterials for regulation of cellular functions. However, existing materials are limited to two-state switching of the presentation and removal of cell-adhesive bioactive motifs that cannot emulate the native extracellular matrix (ECM) in vivo with continuously adjustable characteristics. Here, tunable adaptive materials composed of a protein monolayer assembled at a liquid–liquid interface are demonstrated, which adapt dynamically to cell traction forces. An ultrastructure transition from protein monolayer to hierarchical fiber occurs through interfacial jamming. Elongated fibronectin fibers promote formation of elongated focal adhesion structures, increase focal adhesion kinase activation, and enhance neuronal differentiation of stem cells. Cell traction force results in spatial rearrangement of ECM proteins, which feeds back to alter stem cell fate. The reported biomimetic adaptive liquid interface enables dynamic control of stem cell behavior and has potential translational applications. 相似文献
143.
Auditory perception based system for age classification and estimation using dynamic frequency sound
Ilyas Muhammad Othmani Alice Nait-ali Amine 《Multimedia Tools and Applications》2020,79(29-30):21603-21626
Multimedia Tools and Applications - Human age is a crucial factor in social interaction. It determines the way we interact with others. It is also a relevant forensic issue that can provide helpful... 相似文献
144.
Alice S. Tempel 《Journal of chemical ecology》1982,8(10):1289-1298
Techniques used in different biological and industrial fields for the detection and quantification of tannin compounds in plants are discussed. Emphasis is placed on the choice of method for ecological investigations, which may benefit from the use of a method that measures relative astringency of plant extracts at reduced costs in time and equipment, permitting the analysis of larger samples than may be feasible with more sophisticated analytical techniques. 相似文献
145.
Gerhard Gries Regine Gries Alice L. Perez Lilliana M. Gonzales Harold D. Pierce Jr. A. Cameron Oehlschlager Marc Rhainds Mesmer Zebeyou Brou Kouame 《Journal of chemical ecology》1994,20(4):889-897
Small trunk pieces of a freshly felled 10-year-old oil palm,Elaeis quineensis (Jacq.), were placed in a modified Nalgene desiccator, and volatiles captured for six days on Porapak Q. Gas chromatographic (GC) analysis of Porapak-Q-trapped volatiles with both flame ionization (FID) and electroantennographic detection (EAD) using male or femaleR. phoenicis antennae revealed several EAD-active compounds. They were identified as: ethyl acetate, ethyl propionate, isobutyl propionate, ethyl butyrate, and ethyl isobutyrate. In field experiments in the La Me Research Station, Côte d'Ivoire, ethyl propionate (50 mg/24 hr) but not all esters combined (50 mg/24 hr each) significantly increased capture ofR. phoenicis in pheromone-baited (3 mg/24 hr) traps. One kilogram of 1- to 3-day-old palm tissue was significantly more effective than ethyl propionate in enhancing pheromone attraction. Superior attraction of palm tissue may be attributed to additional as yet unknown semiochemicals. Alternatively, release rates and/or ratios of synthetic volatiles differed from those of palm tissue at peak attraction. 相似文献
146.
This application uses live data from a thermoplastic injection moulding manufacturer to examine the feasibility and effectiveness of using backpropagation artificial neural networks for predictive quality control. Preprocessing and post processing of live data, formulating neural predictive strategies, selecting architecture and parameters, and handling of temporal aspects are topics. Performance of the neural networks are compared to other quality control methods, including control charts and statistical techniques. This case study demonstrates that even manufacturers who have modest expertise in computing and limited hardware and software availability can successfully use neural networks for data analysis and modelling. 相似文献
147.
Incorporation of chloramphenicol and captopril into poly(GL)‐b‐poly(GL‐co‐TMC‐co‐CL)‐b‐poly(GL) monofilar surgical sutures 下载免费PDF全文
Yolanda Márquez Tània Cabral Alice Lorenzetti Lourdes Franco Pau Turon Luís J. del Valle Jordi Puiggalí 《应用聚合物科学杂志》2017,134(17)
Incorporation of chloramphenicol and captopril into coated and uncoated monofilament sutures was evaluated, as well as the derived bactericide and wound healing effects. To this end, a commercially available suture and an amorphous random copolymer constituted by trimethylene carbonate and lactide units were considered. The suture had a segmented architecture based on polyglycolide hard blocks and a soft block constituted by glycolide, trimethylene carbonate and ε‐caprolactone units. Chloramphenicol was better loaded when the coating copolymer was employed due to its protective effect whereas captopril showed an opposite behavior due to partial solubilization during immersion in the coating bath. Interestingly, the release behavior was very different for the two studied drugs since a significant retention of chloramphenicol was always detected, suggesting the establishment of interactions between drug and copolymers. On the other hand, delivery of captopril showed a typical dose dependent behavior. A low in vitro toxicity of the two drugs was determined considering both epithelial‐like and fibroblast‐like cells. Bactericide effect of chloramphenicol against Gram‐negative and Gram‐positive bacteria was demonstrated at a dose that was non‐toxic for all assayed cells. An accelerating wound healing effect of captopril was also demonstrated for early events. In this case, the use of a coating copolymer was fundamental to avoid cytotoxic effects on highly loaded sutures. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44762. 相似文献
148.
Richard W. Gilpin Susan B. Dillon Patricia Keyser Alice Androkites Mary Berube Nichola Carpendale Jane Skorina James Hurley Adele M. Kaplan 《Water research》1985,19(7):839-848
Continuous ultraviolet light (u.v.) and chemical disinfection of circulating water systems were evaluated. Direct comparisons of the biocidal effectiveness of u.v. light vs halogenation were tested with Legionella spp and Pseudomonas aeruginosa because of their association with the acquisition of overt clinical disease from water-containing appliances. Findings indicated that six species of Legionella and P. aeruginosa were killed by a moderate level of u.v. radiation. L. pneumophila and other bacteria in a circulating water system were effectively killed by a biocidal u.v. light. However, free chlorine levels needed to kill Legionella, Pseudomonas, and Flavobacterium within 1 min were found to be greater than 4 mg ml?1. Data from a long-term field trial with u.v. light treatment of evaporative condenser water showed a significant reduction in numbers of bacteria. Ultraviolet disinfection of hospital hydrotherapy whirlpools confirmed the utility of this mode of disinfection under circumstances where chlorination may not be practical for medical reasons. These findings were confirmed during investigations of halogenated or u.v.-treated public hot tub/whirlpools. The effectiveness of routine chemical disinfection for controlling microbial flora in a cooling tower was also evaluated. The 2 month survey indicated that the numbers of bacteria, including Legionella, were not affected by two biocides that were used. The observations made during this investigation support the conclusion that u.v. light disinfection of water-containing systems may be an appropriate alternative or supplement to chemical biocides. 相似文献
149.
Developing Structural Integrated Stressor–Stress Models for Clients’ and Contractors’ Cost Engineers
Mei-yung Leung Yee-shan Chan Alice Chong Janet Fung-Chu Sham 《Canadian Metallurgical Quarterly》2008,134(8):635-643
Estimation is not a purely scientific task. It requires cost engineers equipped with a wide knowledge of construction and a professional ability to make judgments. However, stress will deaden their use of knowledge and influence their professional judgment in estimating. In the construction industry, cost engineers can generally be divided into two main groups: clients’ cost engineers in consultant firms or in a development company who serve clients; and contractors’ cost engineers in construction companies working for the contractors. This study investigates the causal relationships between the stressors and stress of clients’ and contractors’ cost engineers. Two stressor–stress integrated models were developed for these two cost engineer groups by using the structural equation model. The findings revealed some stressors that affected both clients’ and contractors’ cost engineers: (1) poor environment, role conflict and work underload affect their stress positively; (2) social support and Type A behavior affect their stress negatively; and (3) work underload induces stress via the role conflict among cost engineers, their supervisors, and the organization. On the other hand, some deviations between these two groups of cost engineers also occur: (1) social support acts as a source of stressors of clients’ cost engineers; (2) a private life stressor only affects the stress of contractors’ cost engineers; and (3) a closed interactive looping relationship among role conflict, Type A behavior, and work underload affects contractors’ cost engineers. Based on the results of this study, some recommendations are suggested to manage cost engineers’ stress well. 相似文献
150.
Fung Helene H.; Lu Alice Y.; Goren Deborah; Isaacowitz Derek M.; Wadlinger Heather A.; Wilson Hugh R. 《Canadian Metallurgical Quarterly》2008,23(2):440
Socioemotional selectivity theory postulates that with age, people are motivated to derive emotional meaning from life, leading them to pay more attention to positive relative to negative/neutral stimuli. The authors argue that cultures that differ in what they consider to be emotionally meaningful may show this preference to different extents. Using eye-tracking techniques, the authors compared visual attention toward emotional (happy, fearful, sad, and angry) and neutral facial expressions among 46 younger and 57 older Hong Kong Chinese. In contrast to prior Western findings, older but not younger Chinese looked away from happy facial expressions, suggesting that they do not show attentional preferences toward positive stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献