Abstract: What this article focuses on is the method of calculation of the determinant. It Introduces several methods and gives some typical examples,at the same time, the article also illustrates the requirements necessary listed after each method. As a result, it makes it possible that we can choose the computing method as soon as we observe the determinant, which can simplify the calculation.
With the increasingly prominent energy issues, sustainable development has become a common problem of the new era of all mankind to overcome. Therefore, use appropriate evaluation methods and indicators to study solar factors influencing the heat transfer performance of heat exchanger, and summed up the improvement in practical engineering method, not only has important theoretical significance, and to make up for the future of the huge energy gap has great strategic significance. In this paper, drawing on the basis of the existing empirical formula, for a given set heat exchanger model and comprehensive study of the various factors for solar set heat exchanger thermal efficiency of the set, and evaluation parameters of the collector are deduced, and calculation of effect factors for the trend of the impact parameter to evaluate the obtained the collector under different flow rate and different inlet and outlet temperature conditions of heat collecting efficiency. The trend diagram of the evaluation parameters of the collector and the flow rate and the inlet and outlet temperature change trend is drawn, and the high efficiency operating parameters of the collector are obtained, which provides theoretical basis for improving the heat collection efficiency.
Abstract
Expands unceasingly along with the school scale, the student quantity sharp growth, concerned student's each kind of information content also becomes time of growth. Facing the huge information content, needs to have the correlation information management system to enhance the student supervisory work the efficiency. Through such system, may achieve the information the standard management, the science statistics and the fast inquiry, thus the reduced management aspect work load, brings enormous convenient for the teaching office. Without a doubt, effectively introduces practically the computer management in the school information management, regarding the promotion control system, improves the school quality of teaching and the school level has the remarkable significance. In order to adapt the modern society people highly intense time idea, the full use existing computer universalization this social environment and the student manage the actual situation, I decided develops "Student Information management system". According to school actual situation, if the financial resource to the electronic work system support dynamics, I choose use Microsoft Corporation Visual the Basic 6.0 development kits, not only it requests lowly to the system hardware environment, may save the massive funds for the school.Moreover it provided has used in to us visiting the data from the database the powerful tool collection, used it to be possible to establish the development quite perfect database operation application procedure, and provided the database using SQL Server2000.The article introduced the student management information system system analysis part, including demand analysis, development design concept and so on; The system design part mainly introduced the system module design and the database design; The system detailed design and the code design mainly introduced several main module code design, the operation flow, as well as contact surface characteristic and so on.The system test mainly introduced the system test way and the test result.This system contact surface is friendly, the operation is simple, quite practical.
摘要用英文表达为digest或是abstract，读音为[daɪˈdʒest,dɪˈdʒest]，[ˈæbstrækt]。重点词汇解释：1、digestvt. 消化；吸收；融会贯通vi. 消化n. 文摘；摘要双语例句：
He read rapidly but did not digest anything. 他读得很快，但什么也没领会到。2、abstractadj. 纯理论的；抽象的；抽象派的n. 摘要；抽象；抽象的概念；抽象派艺术作品v. 摘要；提取；抽象化；退出；转移；使心不在焉双语例句：His abstracts are held in numerous collections.他的抽象画被纳入到很多收藏中。扩展资料：abstract的用法：abstract 的基本意思是抽象的，观念上的，理论的，可与个别情况相对，也可与具体经验相对。多指品质或特征，而不指物体或事实。有时意味着脱离现实，而且缺乏对实际事物的专门实用性，引申可作难懂的，过于深奥的意思。abstract用于艺术作品时可指抽象派的。abstract作抽象的，抽象派的意思时不用于比较等级，作难懂的，过于深奥的意思时可用于比较等级。abstract用作名词时其意思有以下几点：一是抽象概念；二是抽象派艺术作品，如抽象画，抽象雕塑，抽象设计等；三是文献等的摘要，概要，梗概，多指学术或法律方面比较艰深或复杂的文字摘要。abstract常用于短语in the abstract中，意思是就一般而言，抽象地，在理论上，abstract前的定冠词the不可遗漏。
