蚕茧削口设备研究报告

茧丝绸业是我国的传统优势产业,蚕种场在生产蚕种过程中,为了进行蚕蛹的雌雄鉴别,须对蚕茧进行切削处理。目前,蚕茧切削还是由人工来完成。本文根据蚕茧自动削口机的创新研发过程,论述了作者对蚕茧自动削口设备研究的发展思路和项目的研制现状。同时,介绍了设计者采用的多项独特设计和创新点。     

Selection as contract to teach at the student's level. Experiences from a South African mathematics and science foundation year

The selection of students is a critical issuecurrently facing South African higher educationinstitutions. The identification and selection ofdisadvantaged students with the potential to succeedin mathematics- and science-based study is aparticularly pressing problem. The new South Africanhigher education law requires that selection is donein a fair and transparent manner. Selection has to befollowed by adequate support for selected students tosucceed in their study programmes. Issues of accessare closely coupled to issues of retention andsuccess. The research results discussed in this paperillustrate how these issues can be successfullyaddressed and how selection fairness and effectivenessmay be optimised under the constraints of selectionefficiency. An optimal solution can be found bydeveloping test specifications and selection cut-offvalues based on the teaching programme for which theselection is done. The resulting close fit betweenselection testing and teaching after selection leadsto a reasonable expectation of success for selectedstudents in the study programme. Under suchconditions, selection can be seen as a contract toteach at the student's level.     

AN INVESTIGATION OF BANDWIDTH IN DIELECTRIC SLAB LOADED RECTANGULAR WAVEGUIDE

Several technical problems of numerical method in TLM procedures arediscussed.The bandwidth of single mode in four kinds of dielectric slab loaded rect-angular waveguides is investigated,and the optimum bandwidth which is related tothe dimensions and dielectric constants is obtained.These results are useful to the de-sign of dielectric slab loaded rectangular waveguide.     

电流截止负反馈自动调速控制电路设计

在电压负反馈和电流正反调速控制系统中增设了自动限制电枢电流的电路,并能实现在正常运行时限制电枢电流电路与负反馈调速控制系统自动分离,当电流增大到一定程度时又能自动投入.既克服了由于电流负反馈使系统的静特性变软的不足,又能满足一般调速系统的要求.     

Application of High-Density Seismic Image in Nondestructive Exploration of Cut-off Cement-Soil Wall in Earth Dam

In order to quickly explore the quality of cut-off wall in dams, a new method of high-density seismic image was adopted and estimated by model and in-situ wall tests. The vibration exciter was employed and several parameters such as hypocentral distance, length of signal record and sampiing space in signal collection were determined, which are 8 m, 0.25 ms and 128 ms respectively. Through time and frequency field signal analyses, it is concluded that, the smaller arrival times of reflected longitudinal and surface waves, and the higher their main frequencies, the higher the strength of the wall, vice versa. Accordingly the construction quality of the wall can be evaluated quickly by high-density seismic image.     

复杂地质条件下深防渗墙成槽新工艺

介绍了在堤身质量差、堤基地质条件复杂情况下，深防渗墙施工的新工艺，重点论述了存在紧密胶结砂夹层时，采用液压抓斗和射水法联合成槽新工艺的成功经验。     

截止测试在业务循环审计中的应用

会计分期是会计核算的前提之一。会计分期限定了会计核算的时间范围,为权责发生制、配比原则等会计原则奠定了理论基础。截止的理论来源于会计期间的演进,接近结账日的业务往往隐藏着错报的风险,注册会计师通常有必要在审计财务报表时安排截止日测试。判断同一业务引起的借贷双方是否在同一会计期间入账被广泛应用于许多会计报表项目的审计中,尤其以在销售与收款循环和生产循环等项目的审计中更为典型。     

截止频率对LoG算子边缘检测的影响分析

高斯型拉普拉斯（LoG）算子采用高斯滤波器平滑图像。高斯滤波器需要控制截止频率来改变滤波的效果,本文主要分析高斯低通滤波器和LoG算子的各种特点,通过计算机模拟来分析含噪声图像的滤波后对LoG算子边缘检测的影响。     

平行线中的桥梁——浅谈中学数学中的截线作用

中学数学中三线八角中截线其实是非常重要的,很多时候学生往往只重视两条平行的直线而忽视了截线的重要作用。本文围绕中学数学中的截线作用做了相关研究。     

亏损产品是否停产的决策方法

决策是现代企业管理的关键和核心,管理的重心在经营,经营的重心在决策,决策的正确与否直接关系到企业的盛衰兴亡。现代企业应坚持科学发展观,依照现代管理会计的观点,对亏损产品是否停产进行实证分析后,作出正确的决策,实现企业可持续发展。