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61.
It is by now familiar that in the deployment of solar photovoltaic (PV) systems, the cost dynamics of major system component like solar cell/module is subjected to experience curve effects driven by production learning and research and development at the supplier side. What is less clear, however, is the economics of system integration or system deployment that takes place locally close to the user, involving other market players, in the downstream solar PV value chain. Experts have agreed that suppliers of solar PV system must customize their flexible characteristics to address local unique users’ and applications requirements and compete on price/performance basis. A lack of understanding of the drivers of the economics of system customization therefore is a deficiency in our understanding of the overall economics of this renewable energy technology option. 相似文献
62.
A hierarchical computing scheme for power system state estimation is developed by carefully considering mismatches arising from the system decomposition. The method makes use of an extension of a fast second-order load-flow method that allows a fixed Jacobian matrix to be used in the hierarchical algorithm. In the problem formulation, the power network is decomposed into two or more subsystems; the interaction among them is taken into account through the tie-line bus voltages. The hierarchical structure of the method consists of two levels: the upper level, where the optimal tie-line bus voltages are evaluated; and the lower level, where the optimal states of each subsystem are determined by minimizing a cost function that involves the entire system. Three test cases using the method are reported here and the test results are compared with those obtained by another hierarchical power system state estimation method 相似文献
63.
The relative distribution of types I and III collagens and collagen fibre architecture in the perimysium and endomysium were compared to the longissimus thoracis (LT) and pectoralis profundus (PP) muscles in pigs. The LT muscle was composed of type I myofibres 16.8%, IIA 12.9% and IIB 70.2%, and the PP muscle was 25.4, 23.1 and 51.5%, respectively. The total collagen amount differed significantly between the LT (2.66 mg/g) and PP (4.13 mg/g) muscle (P<0.001). On image analysis of the immunohistochemical preparations for types I and III collagens, the percentage area of the perimysium to the total collagen area showed significant differences between the muscles, where perimysial type I collagen occupied 25.4% of the total area in the LT muscle and 45.7% in the PP and perimysial type III 37.6 and 54.5%, respectively (P<0.001). In scanning electron microscopic photographs of the macerated preparation, very thick collagen layers composed of several fibre bands were observed in the perimysia of the PP muscle and appeared differently from the thinner perimysia with a few bands in the LT. Similar architecture of endomysial collagen fibres were observed around every myofibre type in the PP muscle and also in the LT. The fine surface cover of reticular collagen fibres around an adipocyte was shown as a global cast. These results suggested that the total collagen amount of the PP muscle was related mainly to the well developed perimysia composed of several collagen bands, indicating tougher meat compared with the LT muscle. 相似文献
64.
N Segawa Y Iwamoto H Azuma K Yamamoto H Ueda Y Katsuoka 《Canadian Metallurgical Quarterly》1998,44(9):627-631
Intravesical instillation of Tokyo 172 strain bacillus Calmette-Guerin (BCG) after transurethral resection of bladder tumor (TUR-Bt) was applied to 35 patients with superficial bladder cancer. The patients received 80 mg of BCG in 40 ml saline infused into the bladder once a week for 6 weeks. Actuarial non-recurrence rates for all 35 patients were 81.7% and 58.4% at one and two years after the BCG therapy, respectively. The recurrence of the bladder cancer after the BCG therapy was observed in 12 patients 3-27 months later. Seven patients received an additional course of BCG instillation, and 6 (86%) showed no further recurrence. Thus, the overall success rate of 2 cycles of BCG instillation was 83% (29 of 35 patients). Moreover, in some cases intravesical BCG instillation was effective for recurrent superficial bladder cancer after intravesical instillation of anti-cancer agents and prolonged the period until recurrence. The progression rate was only 5% (2 of 35 patients). These results suggest that intravesical BCG therapy for superficial bladder cancer helps prevent disease progression. 相似文献
65.
On the heat removal characteristics and the analytical model of a thermal energy storage capsule using gelled Glauber's salt as the PCM 总被引:1,自引:0,他引:1
Akio Saito Seiji Okawa Tadafumi Shintani Ryuichiro Iwamoto 《International Journal of Heat and Mass Transfer》2001,44(24):4693-4701
An analytical and experimental investigation was performed on a heat removal process of the thermal energy storage (TES) capsule, using gelled Glauber's salt. Transient heat flux at the capsule wall was measured for various cooling conditions. In cases where the initial temperature was lower than the saturation temperature of the phase change material (PCM), numerical analyses were performed, approximating the process by a relaxation phenomenon where crystals grew around crystal nuclei. The results of the numerical solution agreed very well with the experimental results. 相似文献
66.
Kazuo Matsuda Kenichi Kawazuishi Yoshiichi Hirochi Rei Sato Yasuki Kansha Chihiro Fushimi Yutaka Shikatani Hiroshi Kunikiyo Atsushi Tsutsumi 《Applied Thermal Engineering》2010,30(16):2300-2305
The reaction section of the naphtha hydro-desulfurization (HDS) process is a heating and cooling thermal process consisting of a feed/effluent heat exchanger and a fired heater. Energy savings are fundamentally made as a result of the maximized heat recovery in the heat exchanger and the reduced heat duty of the fired heater. To achieve further energy saving in the process, “self-heat recuperation technology” (SHRT) was adopted. In this technology, a compressor was introduced. The suction side of the compressor needed a lower pressure and the feed stream evaporated much easily. The discharged side of the compressor satisfied the operating conditions of both pressure and temperature at the inlet of the reactor. And the reactor effluent stream was able to be used completely to preheat and vaporize the feed stream. All the heat in the process stream was re-circulated without using a fired heater. SHRT was applied to the naphtha HDS process of 18,000 barrel per stream day (BPSD) in the refinery and the mass and energy balance of the process was calculated using commercially available simulation software, Invensys PROII version 8.1. This process-simulation case study confirmed that despite there being no more energy saving potential in the conventional process that makes use of a fired heater, the advanced process with SHRT can reduce the energy consumption significantly by using the recuperated heat of the feed stream. 相似文献
67.
68.
Miyanishi N Iwamoto Y Watanabe E Odaz T 《Journal of Bioscience and Bioengineering》2003,95(2):192-195
We prepared a beta-1,3-glucan oligomer (DP> or = 4) from laminarin (DP: 25-30) derived from Laminaria digitata with beta-1,3-glucanase, and examined its effect on human peripheral blood monocytes. Conditioned medium prepared by incubating monocytes (MC-CM) with the beta-1,3-glucan oligomer showed strong inhibitory activity against the proliferation of human leukemic U937 cells. Since the beta-1,3-glucan oligomer had no direct cytotoxic effect on U937 cells up to 1000 microg/ml, the cytotoxicity of the MC-CM may be due to cytotoxic cytokines produced from monocytes stimulated by the beta-1,3-glucan oligomer. On the other hand, the MC-CM prepared with original laminarin had little effect on the growth of U937 cells. The cytotoxicity of the MC-CM prepared with the beta-1,3-glucan oligomer was significantly reduced by an anti-TNF-alpha antibody, but the anti-TNF-beta antibody had no effect. Our results suggest that the enzymatically depolymerized beta-1,3-glucan oligomer induces TNF-alpha production from human monocytes. 相似文献
69.
The influence of high concentrations of ferric ions on the biochemical activity of Acidithiobacillus ferrooxidans was studied using intact cells. The specific oxidation rate of ferrous ions decreased with increasing ferric ion concentration. Lineweaver-Burk plots revealed typical competitive inhibition kinetics, because the slopes varied with the ferric ion concentration. A linear relationship between the slope and the square of the ferric ion concentration revealed that the iron-oxidizing enzyme system of A. ferrooxidans was competitively inhibited by about two molecules of ferric ion. The kinetic equation based on this inhibition model agreed with the experimental observation at a high ferric ion concentration where the bacterium is usually exposed in bioleaching and biooxidation plants. 相似文献
70.
The Building-Design Workshop at the Taubman College of Architecture and Urban Planning pursues the integration of teaching, design research, and the design-build process. The program brings University-sponsored projects into the teaching context, offering a unique forum for testing pedagogies about making. Collaborating with faculty on both architectural and constructional aspects of a project, students are given a valuable occasion to realize a design in built form. The project shown here is a renovation of the College's Faculty Resource Room (FRR), a support facility for the research and teaching of the Architecture and Planning faculty. 相似文献