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101.
The primary purpose of this paper is to validate a clustering procedure used to construct contiguous vehicle routing zones (VRZs) in metropolitan regions. Given a set of customers with random demand for pickups and deliveries over the day, the goal of the design problem is to cluster the customers into zones that can be serviced by a single vehicle. Monte Carlo simulation is used to determine the feasibility of the zones with respect to package count and tour time. For each replication, a separate probabilistic traveling salesman problem (TSP) is solved for each zone. For the case where deliveries must precede pickups, a heuristic approach to the TSP is developed and evaluated, also using Monte Carlo simulation. In the testing, performance is measured by overall travel costs and the probability of constraint violations. Gaps in tour length, tour time and tour cost are the measure used when comparing exact and heuristic TSP solutions. 相似文献
102.
Hsiao-Wen Zan Shin-Chin Kao 《Electron Device Letters, IEEE》2008,29(2):155-157
In this letter, the influence of drain bias on the threshold voltage instability in pentacene-based organic thin-film transistors (OTFTs) was studied. By applying different drain biases to adjust the channel carrier concentration in linear mode, the threshold voltage shift was found to be proportional to the carrier concentration. The experimental data can be well quantitatively explained by the drain bias-stress theory developed for a-Si TFTs. The outcome gives the insight of the degradation mechanism of OTFTs and is important for the design of OTFT pixel circuit, OTFT analog amplifiers, or OTFT active loads. 相似文献
103.
104.
针对地理信息系统在获取定位信息中存在的问题,提出了基于串口扩展芯片GM8123的新型通信处理系统设计思想,该系统一方面可接收GPS和激光测距系统提供的定位信息,另一方面可上传定位数据并响应上位PC机和PDA发送的命令。 相似文献
105.
镧系元素钼系双11系列杂多蓝的离析和性质研究 总被引:1,自引:0,他引:1
本文首次报道了镧系元素钼系双11系列两电子杂多蓝K_yH_z[Ln(XMo_(11)O_(39)_2]·nH_2O(X=P,Ln=La、Ce、Pr、Nd、Sm、Gd;X=Si,Ln=Ce、Pr、Sm、Tb、Dy;X=Ge、Ln=Dy)的制备和离析方法.并通过元素分析、红外光谱、可见-紫外光谱、极谱、循环伏安、热分析、ESR、~(31)P NMR、XPS对产物进行了表征及性质研究.结果表明:杂多蓝阴离子结构较之还原前发生了轻微畸变,还原电子具有一定的离域性.在溶液中杂多蓝较还原前的杂多酸(盐)具有略强的氧化能力.溶液中杂多蓝的氧化能力Ln-P(2)>Ln-Si(2).热稳定性Ln-P(2)>Ln-Si(2).该系列杂多蓝还具有较好的抗碱解能力. 相似文献
106.
杂环息夫碱化合物及其过渡金属配合物的合成与表征 总被引:5,自引:0,他引:5
本文合成了一种新的双齿(N,O)杂环息夫碱2-(2′-羟基)苯甲亚胺-5-(4′-硝基)偶氮苯吡啶(HL)与过渡金属的六种新配合物ML_2及M′L_3 [M=Mn(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Pd(Ⅱ);M′=Fe(Ⅲ)].采用元素分析、摩尔电导、红外光谱、紫外—可见光谱、磁化率以及热分析等研究了配合物的组成和性质. 相似文献
107.
Yuanyou Yang Ning Liu Liangbiao Zan Jiali Liao Jiannan Jin 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(2):205-210
Summary Insulin receptors are overexpressed on a number of
human tumors, leading to significant affinity of insulin to these tumors. It
is appealing to receptor-targeted radiotherapy for malignant tumors if insulin
is labeled with suitable radionuclide. In this paper, N-succinimidyl
5-(tributylstannyl)-3-pyridinecarboxylate (SPC), a potential bi-functional
linker for radioiodination of proteins or peptides, was synthesizedby using 5-bromonicotinic acid as the
starting material. Then, with this bi-functional linker, insulin was conjugated
with 131I, and the tissue distribution of the labeled insulin (131I-SIPC-insulin) in normal mice was
investigated. The results showed that insulin </span> could be
conjugated with131I using SPC as the linker </span> in a
labeling yield of40-58%, and with radiochemical purity of more than 98%
after purification bySephadex?G-10. Even kept at room temperature for
72 hours, the radiochemical purity of 131I-SIPC-insulin was still more than 97%, implying
that the conjugated insulin was constantly stable in vitro.Meanwhile, in order to evaluate the in
vivo stability of the conjugated compounds, insulin was also labeled with 131I
by a direct method using chloramine-T (Ch-T) as the electrophilic agents.Biodistribution of131I-SIPC-insulinin
micesuggested that 131I could clear rapidly from the blood,mainly excreted by kidney. However, 131I
uptake of mice with131I-SIPC-insulin
in some key organs, especially in thyroid and stomach, were much less (150 or
30 times) than that with the direct labeled insulin (131I-insulin). Additionally, it was noted
that 131I-SIPC-insulin
hasmuch betterinvivo stability than131I-insulin.</p>
</p> 相似文献
108.
Salih Ilhan Hamdi Temel Recep Ziyadanogullari Memet Sekerci 《Transition Metal Chemistry》2007,32(5):584-590
A new macrocyclic ligand, 1,3,5-triaza-2,4:7,8:15,16-tribenzo-9,15-dioxacycloheptadeca-1,5-diene (L) was synthesized by reaction
of 2,6-diaminopyridine with 1,4-bis(2-carboxyaldehydephenoxy)butane. Then, its CuII, NiII, PbII, CoIII and LaIII complexes were synthesized by the template effect by reaction of 2,6-diaminopyridine and 1,4-bis (2-carboxyaldehydephenoxy)butane and Cu(NO3)2 · 3H2O, Ni(NO3)2 · 6H2O, Pb(NO3)2, Co(NO3)2 · 6H2O, La (NO3)3 · 6H2O, respectively. The ligand and its metal complexes were characterized by elemental analysis, IR, 1H- and 13C-n.m.r., UV-vis spectra, magnetic susceptibility, thermal gravimetric analysis, conductivity measurements and mass spectra.
All complexes are diamagnetic and the CuII complex is binuclear. The CoII complex was oxidised to CoIII. 相似文献
109.
This paper is a continuous study of references[1-2].At first,we introduce theconcept of assembles of ecosystems,and then discuss macro-and micro-synergeticalmethods for ecology study.Combining the two methods,by use of the macroscopic data(observable)outputted from the ecosystems,we can construct their GGLE,master theirinformation changes between,before and after the generalized phase changes(e.g.community successions),and find out the action mechanisms of microscopic factors onmacroscopic results.This may be a new approach to the study of action mechanisms ofcomplex ecosystems. 相似文献
110.
非线性生态系统的复杂动力学行为研究(Ⅲ) 总被引:1,自引:1,他引:0
本文继续文献[1~2]的研究,首先引进了生态系统的系综概念,在此基础上比较详细地讨论了生态协同学的微观方法和宏观方法.将这二者结合起来,利用生态系统输出(或可以测得)的宏观数据,建立广义金兹堡-朗道方程(GGLE),把握广义相变(群落演替)前后的信息变化,找出其微观对客观结果的作用机制,这也许是对复杂生态系统作用机制研究的一条新途径. 相似文献