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1.
This study provides details of the energy management architecture used in the Goldwind microgrid test bed. A complete mathematical model, including all constraints and objectives, for microgrid operational management is first described using a modified prediction interval scheme. Forecasting results are then achieved every 10 min using the modified fuzzy prediction interval model, which is trained by particle swarm optimization.A scenario set is also generated using an unserved power profile and coverage grades of forecasting to compare the feasibility of the proposed method with that of the deterministic approach. The worst case operating points are achieved by the scenario with the maximum transaction cost. In summary, selection of the maximum transaction operating point from all the scenarios provides a cushion against uncertainties in renewable generation and load demand.  相似文献   
2.
弥散强化铜材料具有高强度和高导电性的特性,孔洞是影响导电率的重要因素.本文采用高速压制成形技术,对Al2 O3质量分数为0.9%的弥散强化铜粉压制成形,研究了压制速度对生坯的影响.当压制速度为9.4 m·s-1时得到密度为8.46 g·cm-3的生坯.研究了烧结温度对烧结所得Al2 O3弥散强化铜试样导电率的影响.当生坯密度相同时,烧结温度越高,所得试样的导电率也越高.断口与金相分析表明:烧结温度为950℃时,烧结不充分,颗粒边界以及孔洞多而明显,孔洞形状不规则;烧结温度为1080℃时,颗粒边界消失,孔洞圆化,韧窝出现,烧结坯的电导率为71.3%IACS.  相似文献   
3.
Atriplex rosea L. (Chenopodiaceae; tumbling orach), an annual herb, is a widely established weedy species of disturbed sites in all counties of Utah. Seeds of Atriplex rosea were collected from a salt marsh in Faust, Utah, and are dimorphic, light brown, and 2-2.5 mm wide, or black and 1-2 mm wide. Seed germination responses of the black and brown seeds were studied over a range of salinity and temperature. Both brown and black seeds germinated at 1000 mM NaCl, and the optimal temperature for germination of both types was 20°-30°C. Variation in temperature, however, affected germination of black seeds more than brown seeds. At lower thermoperiod only 40%-50% black seeds germinated in nonsaline control, and germination was almost completely inhibited with the inclusion of salinity. However, all brown seeds germinated in control at temperatures above 5°-15°C, and inhibition caused by salinity was comparatively lower. Brown seeds had a higher germination rate than black seeds at all temperature and salinity treatments. The highest rate of germination of both seeds occurred at the temperature regime of 5°-15°C. Recovery of germination for black seeds when transferred to distilled water after being in various salinity treatments for 20 days was quite variable. Recovery decreased with increase in salinity at lower temperature regimes, increased with salinity at optimal thermoperiod, and had no effect at 20°-30°C. Brown seeds recovered poorly from salinity at all thermoperiods except 5°-15°C, where recovery decreased with an increase in salinity. Brown seeds are adapted to germination in the early part of the growing season, whereas black seeds are capable of surviving harsher conditions and can germinate in later time periods. Characteristics of the dimorphic seeds increase chances for survival in the harsh saline desert environment.  相似文献   
4.
Seeds of two halophytes, Atriplex triangularis, which grows in a mesic saline marsh environment, and Atriplex confertifolia, which grows in a xeric desert environment, were analyzed by energy-dispersive X-ray microanalysis for the distribution of elements. The highest concentration of sodium, chlorine, potassium, and calcium was present in seed coats of A. triangularis. All of the elements detected were at low concentrations in the endosperm. Embryos contained the highest amount of phosphorus that is probably associated with organophosphate compounds. Potassium was also high in embryos. The total amount of elements in all regions of A. confertifolia was low as compared to A. triangularis. In a similar pattern sodium, chlorine, potassium, and calcium were the highest in seed coats of A. confertifolia. Elemental concentration was also low in the endosperm. Likewise, the phosphorus level was the highest in the embryo. The results support the concept of elemental compartmentalization in seeds of these halophytes.  相似文献   
5.
Khan  Haroon-Ur-Rashid  Shi  Feng  Ji  WeiXing  Gao  YuJin  Wang  YiZhuo  Liu  CaiXia  Deng  Ning  Li  JiaXin 《科学通报(英文版)》2010,55(29):3363-3371
This paper evaluates the Triplet Based Architecture, TriBA – a new idea in chip multiprocessor architectures and a class of Direct Interconnection Network (DIN). TriBA consists of a 2D grid of small, programmable processing units, each physically connected to its three neighbors so that advantageous features of group locality can be fully and efficiently utilized. Any communication model can be well characterized by locality properties and, any topology has its intrinsic, structural, locality characteristics. We propose a new criterion in performance evaluation that is based on the concept of locality in an interconnection network, the “lower layer complete connect”. Our proposed criterion depicts how completely a processing node is connected to all its neighbors. TriBA is compared with 2D Mesh and Binary Tree as static interconnection network. The comparison / evaluation is enumerated from three orthogonal view points, viz., computational speed, physical layout and cost. Our analysis concludes that TriBA is computationally efficient interconnection strategy that exploits group locality in processing nodes.  相似文献   
6.
Inositol-1,4,5-trisphosphate receptors (InsP(3)Rs) and ryanodine receptors (RyRs) are tetrameric intracellular Ca(2+) channels. In each of these receptor families, the pore, which is formed by carboxy-terminal transmembrane domains, is regulated by signals that are detected by large cytosolic structures. InsP(3)R gating is initiated by InsP(3) binding to the InsP(3)-binding core (IBC, residues 224-604 of InsP(3)R1) and it requires the suppressor domain (SD, residues 1-223 of InsP(3)R1). Here we present structures of the amino-terminal region (NT, residues 1-604) of rat InsP(3)R1 with (3.6??) and without (3.0??) InsP(3) bound. The arrangement of the three NT domains, SD, IBC-β and IBC-α, identifies two discrete interfaces (α and β) between the IBC and SD. Similar interfaces occur between equivalent domains (A, B and C) in RyR1 (ref. 9). The orientations of the three domains when docked into a tetrameric structure of InsP(3)R and of the ABC domains docked into RyR are remarkably similar. The importance of the α-interface for activation of InsP(3)R and RyR is confirmed by mutagenesis and, for RyR, by disease-causing mutations. Binding of InsP(3) causes partial closure of the clam-like IBC, disrupting the β-interface and pulling the SD towards the IBC. This reorients an exposed SD loop ('hotspot' (HS) loop) that is essential for InsP(3)R activation. The loop is conserved in RyR and includes mutations that are associated with malignant hyperthermia and central core disease. The HS loop interacts with an adjacent NT, suggesting that activation re-arranges inter-subunit interactions. The A domain of RyR functionally replaced the SD in full-length InsP(3)R, and an InsP(3)R in which its C-terminal transmembrane region was replaced by that from RyR1 was gated by InsP(3) and blocked by ryanodine. Activation mechanisms are conserved between InsP(3)R and RyR. Allosteric modulation of two similar domain interfaces within an N-terminal subunit reorients the first domain (SD or A domain), allowing it, through interactions of the second domain of an adjacent subunit (IBC-β or B domain), to gate the pore.  相似文献   
7.
M A Khan 《Experientia》1978,34(6):784-785
Red fibres of the pigeon pectoralis muscle showed high ATPase reaction at pH 9.4. Veronal-acetate pretreatment completely inhibited the ATPase reaction in these red fibres but not in type I fibres of the gastrocnemius. The former are type II red muscle fibres and hence are unlike type I red, the so-called slow-twitch muscle fibres.  相似文献   
8.
本文推广了中国魏宗宣的结果:如果条件[x~my~n-xy~nx,x]=O或[x~sy~t-yx~sy,x]=O.成立,则半素环R是可交换的。其中m,n,s,t是正整数,任意x,y∈R.  相似文献   
9.
Increased attractiveness of man to mosquitoes with induced eccrine sweating   总被引:2,自引:0,他引:2  
A A Khan  H I Maibach  W G Strauss  J L Fisher 《Nature》1969,223(5208):859-860
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10.
Zusammenfassung Ein neues Indolenin-Alkaloid aus der ungetrockneten Wurzelrinde vonRauwolfia caffra Sonder wurde isoliert und charakterisiert.  相似文献   
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