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991.
In periodic review inventory systems, inventory is classified into cycle stock and safety stock. Cycle stock is defined as inventory that absorbs differences between supply and demand frequencies. It can be calculated without deficiency or excess because a method has been established for ensuring that the minimum on-hand inventory during a periodic review is zero. Safety stock is defined as inventory that absorbs various differences between supply and demand. Unlike for cycle stock, a method for calculating safety stock without deficiency or excess remains to be established. An approach is proposed to establishing a method for calculating inventory in which inventory is classified on the basis of the holding purpose and the calculation factors indicate solutions. This approach was applied to inventory held to absorb, on the basis of fluctuations in demand, the difference in terms of time and quantity between supply and demand. Stock held for this purpose is referred to as ‘fluctuation stock’. The objective is to establish a method for calculating fluctuation stock so that the minimum on-hand inventory during a periodic review is zero and to clarify the relationship between fluctuation stock and safety stock. 相似文献
992.
Ellipsoidal load‐domain shakedown analysis with von Mises yield criterion: A robust optimization approach 下载免费PDF全文
Takashi Yamaguchi Yoshihiro Kanno 《International journal for numerical methods in engineering》2016,107(13):1136-1144
The static formulation of elastic shakedown analysis, based upon Melan's lower‐bound theorem, can essentially be viewed as a robust optimization problem. This paper discusses an advantage that is enjoyed by taking this perspective. Specifically, we assume the von Mises yield criterion and an ellipsoidal load domain. In this setting, the shakedown analysis problem, which is viewed as robust second‐order cone programming, can be recast as semidefinite programming. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
993.
Ko‐Chun Lee Shih‐Hsien Yang Yung‐Shang Sung Yuan‐Ming Chang Che‐Yi Lin Feng‐Shou Yang Mengjiao Li Kenji Watanabe Takashi Taniguchi Ching‐Hwa Ho Chen‐Hsin Lien Yen‐Fu Lin 《Advanced functional materials》2019,29(22)
Complementary circuits based on 2D materials show great promise for next‐generation electronics. An ambipolar all‐2D ReSe2 field‐effect transistor (FET) with a hexagonal boron nitride gate dielectric is fabricated and its electronic characteristics are comprehensively studied by temperature dependence and noise measurements. Ambipolar transfer characteristics are achieved owing to the tunable Fermi level of the graphene contact and negligible and 30 meV Schottky barrier heights for the n‐ and p‐channel regimes, respectively. An inverter is also fabricated to demonstrate ambipolar ReSe2 FET operation in a logic circuit. Furthermore, a p/n switchable unipolar FET is designed and shows potential for building complimentary circuits from a signal device. This work demonstrates the potential of all‐2D ReSe2 FETs and makes available new approaches for designing next‐generation devices. 相似文献
994.
Luojun Du Jian Tang Yanchong Zhao Xiaomei Li Rong Yang Xuerong Hu Xueyin Bai Xiao Wang Kenji Watanabe Takashi Taniguchi Dongxia Shi Guoqiang Yu Xuedong Bai Tawfique Hasan Guangyu Zhang Zhipei Sun 《Advanced functional materials》2019,29(48)
Fe3GeTe2 has emerged as one of the most fascinating van der Waals crystals due to its 2D itinerant ferromagnetism, topological nodal lines, and Kondo lattice behavior. However, lattice dynamics, chirality of phonons, and spin–phonon coupling in this material, which set the foundation for these exotic phenomena, have remained unexplored. Here, the first experimental investigation of the phonons and mutual interactions between spin and lattice degrees of freedom in few‐layer Fe3GeTe2 is reported. The results elucidate three prominent Raman modes at room temperature: two A1g(Γ) and one E2g(Γ) phonons. The doubly degenerate E2g(Γ) mode reverses the helicity of incident photons, indicating the pseudoangular momentum and chirality. Through analysis of temperature‐dependent phonon energies and lifetimes, which strongly diverge from the anharmonic model below Curie temperature, the spin–phonon coupling in Fe3GeTe2 is determined. Such interaction between lattice oscillations and spin significantly enhances the Raman susceptibility, allowing to observe two additional Raman modes at the cryogenic temperature range. In addition, laser radiation‐induced degradation of Fe3GeTe2 in ambient conditions and the corresponding Raman fingerprint is revealed. The results provide the first experimental analysis of phonons in this novel 2D itinerant ferromagnet and their applicability for further fundamental studies and application development. 相似文献
995.
Ryo Takata Anita Neumann Dennis Weber Duy‐Vu Pham Ralf Anselmann Yoshitaka Kitamura Takashi Kakimura Satoshi Suzuki Shigeki Minami Mitsumasa Kodama 《Journal of the Society for Information Display》2016,24(6):381-385
An indium oxide‐based precursor solution has been developed by spin coating method. In order to apply this material to mass production, material, process, and equipment optimizations for slot die coating have been implemented. Slot die coating is a cost‐effective and scalable process and already applied to photoresist materials in the display industry. The indium oxide‐based precursor solution has been coated on bare glasses and thin‐film transistor substrates by a mass production‐type slot die coater. Mobility of over 10 cm2/Vs is achieved for the first time for a large area at an annealing temperature of 350 °C. The homogeneity of the film will be presented. 相似文献
996.
Takaya Arita Michał Joachimczak Takashi Ito Atsushi Asakura Reiji Suzuki 《Artificial Life and Robotics》2016,21(2):141-148
Evolutionary developmental biology, evo-devo, emerged to integrate evolution and development in the 1980s, in which evolution is conceptualized as heritable changes in development. Recently, the field is moving to a new synthesis: ecological evolutionary developmental biology, eco-evo-devo. We believe that artificial life (ALife) approach will provide new insights into the field, and also contribute to the field of robotics through the emergence perspective and the constructive methodology. This paper explores the potential of such an artificial life approach based on the evolution of virtual creatures by presenting our ongoing studies with three models: (1) metamorphosis model, (2) exaptation model and (3) Prey-predator model. 相似文献
997.
Macroscopic fundamental diagram (MFD) is a reproducible unimodal relation between average vehicle density and average flow rate in urban traffic. Although this idea is tested by a few observations and simulations, its mechanism is not well understood. In order to understand it, a simple graph-based model of urban traffic is proposed. MFDs in our model system are investigated numerically for grid networks. It is found that MFDs in our system are discontinuous, which is inconsistent with the observation of real urban traffic. 相似文献
998.
Teruo Miyazawa Mari Kikuchi Kenshiro Fujimoto Yasushi Endo Soon-Yeong Cho Riichiro Usuki Takashi Kaneda 《Journal of the American Oil Chemists' Society》1991,68(1):39-43
Chemiluminescence of fresh minced meats of six fish species was measured in order to examine the applicability of chemiluminescence
in the prediction of shelf life. The chemiluminescence intensity of fresh fish meats was increased in proportion to the measuring
temperature and differed significantly among fish meats. The shelf life of fish meats was estimated based on oxidative deterioration
as measured by peroxide, carbonyl and thiobarbituric acid values, as well as sensory evaluation during storage of the fish
meats at 0°C. It was observed that the shelf life of minced fish meats as judged by oxidative deterioration significantly
correlated with chemiluminescence intensity of the fresh meats. The chemiluminescence method was shown to be very available
for the prediction of the shelf life of fish meat. 相似文献
999.
Chiyoshi Kamizawa Hitoshi Masuda Masaji Matsuda Takashi Nakane Hideo Akami 《Desalination》1978,27(3):261-272
Studies on the treatment of citrate buffered gold plating rinse were carried out with four types of membranes. For three membranes (NS-200, polybenzimidazolone, aromatic polyamide), the rejections of gold were more than 92% in the initial stage of the concentration process, but they decreased remarkably with the increase in the concentration of the feed. For the cellulose acetate membrane, negative rejection was observed as Golomb pointed out. To understand the phenomena more clearly, the relationship between the state of the species in the solution and their permeation behavior was investigated in detail. It was shown that in multiion solutions such as gold plating rinse, a less permeable ion such as the citrate ion improved the permeability of a more permeable ion of like charge such as Au(CN)-2. Therefore the recovery of gold was as low as 85% at most in a five-fold concentration of the rinse. 相似文献
1000.
Noriko Seki Eishun Tsuchida Kazuo Ukaji Takashi Sekiya Yoshinori Nozawa 《Polymer Bulletin》1985,13(6):489-492
Summary Hybrid liposomes were prepared from the mixture of dipalmitoyl phosphatidylcholine (DPPC) and di-2,4-octadecadiene phosphatidylcholine (DODPC), and their phase separation behaviours was analyzed. In hybrid liposome systems, two transition temperatures (18 and 41°C for DODPC and DPPC, respectively) were clearly observed by means of DSC and fluorescence techniques. These two transition temperatures were also found after polymerization of DODPC molecules in hybrid liposomes by the UV irradiation. These strongly suggest that DPPC and DODPC molecules do not dissolve well but form clusters in the membrane. This phase separation was directly confirmed by freeze-fracture TEM technique. 相似文献