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1.
This paper presents a new method for power system planning which considers uncertainties of various system parameters as a part of the criterion function. The criterion function involves both the expected values of total system costs and the cost variances of different power plants. Previously, the authors proposed that these cost variances be evaluated from the existing power system plans in the form of the solutions to the inverse optimization problem, and then applied this procedure to the planning of power systems in Japan. However, because of the correlation between fuel and facility costs, the cost variances could not be determined as specific values. Here, to overcome this difficulty, the authors now introduce hydropower plants into the model as the so-called nonrisky elements and focus on the expenditure shares rather than the plant capacity shares. As a result, more reasonable results are obtained. This improved methodology is applied and the derived cost variances are shown. Further, using the resultant cost variances, the authors make Pareto-optimal power generation plans and demonstrate also the robustness of the method to price fluctuations. 相似文献
2.
Fiqri D. Khaidizar Yasumasa Bessho Yasukazu Nakahata 《International journal of molecular sciences》2021,22(7)
Aging is a phenomenon underlined by complex molecular and biochemical changes that occur over time. One of the metabolites that is gaining strong research interest is nicotinamide adenine dinucleotide, NAD+, whose cellular level has been shown to decrease with age in various tissues of model animals and humans. Administration of NAD+ precursors, nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR), to supplement NAD+ production through the NAD+ salvage pathway has been demonstrated to slow down aging processes in mice. Therefore, NAD+ is a critical metabolite now understood to mitigate age-related tissue function decline and prevent age-related diseases in aging animals. In human clinical trials, administration of NAD+ precursors to the elderly is being used to address systemic age-associated physiological decline. Among NAD+ biosynthesis pathways in mammals, the NAD+ salvage pathway is the dominant pathway in most of tissues, and NAMPT is the rate limiting enzyme of this pathway. However, only a few activators of NAMPT, which are supposed to increase NAD+, have been developed so far. In this review, we will focus on the importance of NAD+ and the possible application of an activator of NAMPT to promote successive aging. 相似文献
3.
The dynamic moduli, E′ and E″, and tan δ for nylon–CR and PET–CR composites with unidirectional short fibers were studied as a function of temperature by using a Rheovibron. The temperature dependence of tan δ showed two dispersion peaks for nylon–CR composite. The peak at ?28°C corresponded to the main dispersion of CR and the peak at 100°C to the α-dispersion of nylon 6. For a PET-CR composite, in addition to the individual dispersion of CR and PET, a small and broad peak was observed at about 90°C. The angular dependence of E′ indicated that the short fibers assumed good orientation. The storage modulus for the composites was given by the parallel model as E′ = Vf′Ef + VmE′m., where E′c, E′f and E′m were the storage modulus for the composite, fiber, and matrix and Vf and Vm were the volume fraction of fiber and matrix, respectively. In the transverse direction of fiber, the peak values of tan δ at ?28°C were given by the following equation; tan δc = tan δm ? δVf, where tan δc and tan δm are the loss tangent for the composite and matrix, respectively, and α is coefficient depending on fiber type. The results indicated that a region with strong interaction was formed between fibers and CR matrix. 相似文献
4.
The configurational sequences of 1,2-unit in a series of hydrogenated syndiotactic 1,2-polybutadienes were determined in relation to the sequence distribution of 1,2- and 1,4-units on the basis of the 13C-n.m.r. signal assignment of the methyl carbons. The observed triad distributions of 1,2- and 1,4-units and configurational distributions of the 1,2-unit are in good agreement with the calculated distributions from transition probabilities. The number average sequence lengths of the 1,2-unit and the 1,2-unit in the racemic addition are 5.7 to 8.0 and 4.1 to 5.4, respectively. From the extrapolation of the plot of the number average sequence length against the crystallinity of the starting 1,2-polybutadienes, the minimum sequence length for crystallization is estimated to be 3.7 for the 1,2-unit in the racemic addition. 相似文献
5.
Analysis of Energy Saving and Environmental Characteristics of Electric Vehicles in Regionally Disaggregated World Energy Model
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This paper investigates the impact of an extensive introduction of electric vehicles (EV) and plug‐in hybrid vehicles (PHEV) into the global energy system by 2050. The significant growth of automobile ownership in emerging countries is likely to increase world oil demand and the associated carbon dioxide emissions. In order to address these energy, security, and environmental concerns, the deployment of clean energy vehicles, such as EV and PHEV, is expected to play a crucial role due to their high fuel efficiency. Consequently, we develop both a global energy system model and a world vehicle penetration model, which can explicitly analyze the impact of EV introduction into the seasonal daily electric load curve, with consideration of the specific electricity charging profile through 2050. The simulation results confirm that EV deployment contributes to energy conservation, because oil demand reduction outstrips the growth in electricity demand and the associated fuel input into the power generation mix. Concerning carbon dioxide abatement, the magnitude of the impact relies on the carbon intensity of the power generation mix. If the intensity is low enough to guarantee a carbon mitigation effect due to EV fuel saving, emissions reduction is well assured. It should be noted, however, that in regions with high carbon intensity in the power generation mix, carbon emissions per mileage of EVs is almost equivalent to that of efficient gasoline vehicles such as hybrid vehicles, and the figure for PHEV is slightly higher than for hybrid vehicles. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 20–36, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22373 相似文献
6.
A novel saccharide sensor that displays a distinct color change resembling a “traffic signal” was developed. By copolymerizing boronic acid and amine monomers on a glass plate, a boronic acid‐containing thin film was obtained. Anionic blue and yellow dyes were adsorbed on the thin film, and the film was immersed in aqueous saccharide solutions containing a cationic red dye. With increase in the saccharide concentration in the solution, the thin film changes color from green to red via yellow. The observed distinct changes in color were attributed to a stepwise release and binding of dyes. The sensitivity of the saccharide sensor was dependent on the monomer composition of the thin film and increased with increasing the boronic acid content. The pH of the saccharide solution was another key factor affecting the sensing behavior, and glucose‐responsive color changes were significantly enhanced at pH 7.8. By optimizing these conditions, significant color changes in response to glucose were achieved. Saccharide selectivity was found to be in the following order: fructose > glucose > galactose = mannose > sucrose. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42679. 相似文献
7.
Hitoshi Suto Yasuo Hattori Hiromaru Hirakuchi Naoto Kihara Yasumasa Nakashiki 《Structure and Infrastructure Engineering》2017,13(10):1359-1371
Steel corrosion under atmospheric conditions is a critical issue in the maintenance of structures such as electric transmission towers and bridges during their long-term operation, which are generally located at many places over a wide area. Since a major factor causing corrosion is airborne salt particles coming from the sea, wide-area distributions of the long-term cumulative amount of sea salt deposited on surfaces are needed. Moreover, since the amount of airborne sea salt varies locally with the topography, it is also important to consider the effects of topography. In this paper, a method combining a computational fluid dynamics model and a statistical procedure is proposed to efficiently estimate wide-area distributions of the cumulative amount of airborne sea salt by considering the local topography. The predicted amount of airborne sea salt decreases with increasing distance from the coast and varies with the topography and the offshore wind. A comparison between predicted and observed amounts revealed that: (1) this method appropriately estimates topographical effects on sea-salt transport and enables the estimation of deposited sea salt on structure surfaces, and (2) consideration of the trapping efficiency of sea-salt particles on structure surfaces improves the prediction accuracy. 相似文献
8.
Yasumasa?Minemoto Shuji?AdachiEmail author Yuji?Shimada Toshihiro?Nagao Toshio?Iwata Yoshie?Yamauchi-Sato Takaya?Yamamoto Tadashi?Kometani Ryuichi?Matsuno 《Journal of the American Oil Chemists' Society》2003,80(7):675-678
The autoxidation processes of the cis-9,trans-11 (c9,t11) and trans-10,cis-12 (t10,c12) isomers of CLA were separately observed at ca. 0% RH and different temperatures. The t10,c12 CLA oxidized faster than the c9,t11 isomer at all tested temperatures. The first half of the oxidation process of t10,c12 CLA obeyed an autocatalytic-type rate expression, but the latter half followed first-order kinetics. On the other hand,
the entire oxidation process of c9,t11 CLA could be expressed by the autocatalytic-type rate expression. The apparent activation energies and frequency factors
for the autoxidation of the isomers were estimated from the rate constants obtained at various temperatures based on the Arrhenius
equation. The apparent activation energies for the CLA isomers were greater than those for the nonconjugated n−6 and n−3 PUFA
or their esters. However, the enthalpyentropy compensation held during the autoxidation of both the CLA and PUFA. This suggested
that the autoxidation mechanisms for the CLA and PUFA were essentially the same. 相似文献
9.
以连接端子、印刷电路板和电镀通孔3种不同材料构成的一种可拔插截面针型汽车电子连接器为研究对象,为满足其在非塑性状态下相互接触实现可反复拔插、稳定低电阻的连接要求。针对连接可靠性设计问题,利用接触动力学理论,对基于设计参数变化的连接器米赛斯应力和接触应力分布进行了解析和灵敏度分析,得到了影响其连接性能的关键设计参数。文中为减少高精度设计参数灵敏度解析的计算时间,提出了将连接端子前、后段形态设计参数分离的解析法,即在接触力学解析过程中,首先以准静态接触方法对连接端子后段(连接形态)设计参数进行接触力学解析,再以动态接触方法对连接端子前段(插拔形态)设计参数进行接触力学解析的方法。其结果对同类微小型可拔插截面针型汽车电子连接器设计参数的确定具有参考价值。 相似文献
10.
Yasumasa Fukushima 《Polymer Bulletin》2001,45(6):465-470
Summary
Conventional solution polycondensation of adipoyl chloride with ethidium bromide provided a new polyamide containing ethidium
bromide in a polymer main chain. The polyamide was characterized by TGA, DSC, solubility, and absorption and fluorescent spectroscopy.
A Good optical-quality film was obtained from HFIP solution of the polyamide. The polyamide showed blue-shift in the absorption
band and high fluorescent intensity compared with ethidium bromide.
Received: 4 September 2000/Revised version: 27 November 2000/Accepted: 28 November 2000 相似文献