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41.
成巍  李卉  李乙  郭玉鹏 《化学教育》2022,43(14):13-16
吉林大学化学学院秉持立德树人的根本任务,以“厚基础、重实践、严要求”为理念,探索了改革开放后具有吉大特色的本科与研究生贯通创新型人才培养模式。以先进的教学科研理念、雄厚的师资队伍、完善的人才培养体系、优质的平台支撑为基础,培养了一大批杰出的化学家,为我国化学领域的教育事业和科学研究奠定了深厚的基础,成为培养高素质化学人才的一方沃土。  相似文献   
42.
Structure–activity relationship (SAR) models are recognized as powerful tools to predict the toxicologic potential of new or untested chemicals and also provide insight into possible mechanisms of toxicity. Models have been based on physicochemical attributes and structural features of chemicals. We describe herein the development of a new SAR modeling algorithm called cat-SAR that is capable of analyzing and predicting chemical activity from divergent biological response data. The cat-SAR program develops chemical fragment-based SAR models from categorical biological response data (e.g. toxicologically active and inactive compounds). The database selected for model development was a published set of chemicals documented to cause respiratory hypersensitivity in humans. Two models were generated that differed only in that one model included explicate hydrogen containing fragments. The predictive abilities of the models were tested using leave-one-out cross-validation tests. One model had a sensitivity of 0.94 and specificity of 0.87 yielding an overall correct prediction of 91%. The second model had a sensitivity of 0.89, specificity of 0.95 and overall correct prediction of 92%. The demonstrated predictive capabilities of the cat-SAR approach, together with its modeling flexibility and design transparency, suggest the potential for its widespread applicability to toxicity prediction and for deriving mechanistic insight into toxicologic effects.  相似文献   
43.
A new program, PHI, with the ability to calculate the magnetic properties of large spin systems and complex orbitally degenerate systems, such as clusters of d‐block and f‐block ions, is presented. The program can intuitively fit experimental data from multiple sources, such as magnetic and spectroscopic data, simultaneously. PHI is extensively parallelized and can operate under the symmetric multiprocessing, single process multiple data, or GPU paradigms using a threaded, MPI or GPU model, respectively. For a given problem PHI is been shown to be almost 12 times faster than the well‐known program MAGPACK, limited only by available hardware. © 2013 Wiley Periodicals, Inc.  相似文献   
44.
利用《航海天文历》查表的方法来获得罗经差的计算过程比较复杂.基于C Builder语言编程,根据观测太阳测定罗经差的计算公式,提出了一种新型的天测罗经差算法.以某舰实测数据为基础,进行计算机仿真,结果表明该方法克服了传统的查表法计算繁琐、不能满足实时定位的缺点,提高了计算效率和计算精度,具有一定的可行性.  相似文献   
45.
ESD control programs that are based on the standards IEC61340-5-1 and ANSI/ESD S20.20 are targeted to provide safer handling of electronic parts now susceptible to damage by electrostatic discharge. However, ESD failures have occurred in EPA even when all standard control methods are met. To further improve EPAs, ESD control programs should be updated to cover all known common discharge scenarios, and multiple parallel ESD source parameters should be used to assess the level of ESD risks. In addition, a reliable ESD risk assessment should be based on discharge source circuit analysis and product sensitivity tests using the real discharge waveforms found in EPA.  相似文献   
46.
“本博学位论文连做”培养模式是学士论文阶段在夯实理论基础的同时,改变本科阶段以学习课程为主的思维模式为以创新研究为主的思维模式;短暂的硕士阶段在理论知识进一步升华的基础上掌握本学科的研究现状和发展方向,提升发现问题、分析问题和解决问题的能力;博士阶段瞄准学科前沿,启发其发掘“新方法”和“新思路”,有效地实现学士学位论文和博士学位论文连做。  相似文献   
47.
In this paper, we study inverse optimization for linearly constrained convex separable programming problems that have wide applications in industrial and managerial areas. For a given feasible point of a convex separable program, the inverse optimization is to determine whether the feasible point can be made optimal by adjusting the parameter values in the problem, and when the answer is positive, find the parameter values that have the smallest adjustments. A sufficient and necessary condition is given for a feasible point to be able to become optimal by adjusting parameter values. Inverse optimization formulations are presented with 1 and 2 norms. These inverse optimization problems are either linear programming when 1 norm is used in the formulation, or convex quadratic separable programming when 2 norm is used.  相似文献   
48.
定义了半定乘性规划问题,提出一种求解它的外部逼近算法,并通过具体的实例说明算法的可行性.  相似文献   
49.
Let λ(n) be the n-th normalized Fourier coeficient of a holomorphic Hecke eigenform f(z) ∈ Sk(Γ) for the full modular group.In one of his papers,Sankaranarayanan mentioned that it is an open problem to give a non-trivial estimate for the sum of λ(n) over cubes,i.e.n x λ(n3).In this paper,we are able to use the analytic properties of symmetric power L-functions to solve his problem.More precisely,we prove that Σn≤zλ(n3) x(3/4 +ε),Σn≤zλ(n4) x(97+ε).  相似文献   
50.
We carry out a systematic study of the different contributions to the deviations of the elliptic flows from the quark number scaling in high energy heavy ion collision in a quark combination model.The effects that we considered are:the resonance decay,the flavor dependence of the quark elliptic flow and the combination of quarks/antiquarks with slightly different transverse momenta.Our results show that the deviations observed in experiments can be well reproduced within the combination framework if all the three effects are considered. We make a detailed analysis of the different contributions using a Monte-Carlo program and suggest measuring the quark number scaling in intermediate pT range more precisely.  相似文献   
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