查询词典 variable-density system

objective to study the correlation among psychosomatic health factors,depression,anxiety and sleep status in college students,to analyze influence factors in sleep status.methods with questionnaire opened in-vestigation,200college students were evaluated using cornell medical index,self-rating depression,self-rating anxiety scaleand pittsburgh sleep quality index.stepwise regression analysis was used.re-sults total score of sds was35.55±7.8,and sas was0.48±0.9.each score of cmi was higher than normal range,the highest was digestion system,next was respiration system,then,fatigue,eyes and ears,anxiety,sensitivity,tension,maladjustment in turn.total average score of psqi was6.32±3.6,ordinary sleep were115cases（57.5%）,good and bad sleep were42（21%）and43（21.5%）cases respectively.influence factors in total score of psqi were sas,cmi,respiration system,anxiety,past healthy,digestion system,fatigue,sensitivity,sds and malad-justment in turn,using stepwise regression analysis,total score of psqi as dependent variable,each factor score of cmi,total score of sds and sas as independent variables.conclusion problems of psychosomatic health,anxiety and depression could both lead to sleep disorder.

目的 研究在校大学生心身健康因素及抑郁焦虑等与睡眠状况的相关性，并对影响睡眠状况的有关因素进行分析。方法采用问卷式的开放性研究，对在校的200名大学生进行康奈尔心身健康问卷、自评抑郁量表、焦虑自评量表和匹兹堡睡眠质量量表的测定，采用逐步回归分析方法。结果 sds总分为35.55±7.8、sas总分为0.48±0.9，cmi评分：消化系统最为严重评分为2.52，其次为呼吸系统、疲劳感、眼和耳、焦虑、敏感、紧张、不适应等，评分均高于正常常模。psqi总均分为6.32±3.6，一般睡眠有115例占57.5%，睡眠质量较好42例占21.0%，睡眠质量较差43例占21.5%。评估对睡眠状况的影响程度，以psqi总分为因变量，选择cmi各因子分和sds、sas总分作为自变量，进行多因素逐步回归分析，进入方程的因素依据标准化偏回归系数，影响psqi总分的因素依次为sas总分、cmi总分、呼吸系统、焦虑、既往健康、消化系统、疲劳感、敏感、sds总分、不适应（f=226.8；p.01；r=0.73）。结论心身健康问题和焦虑抑郁可导致睡眠障碍。

To bias flywheel system, based on variable structure control theory, an uncoupled variable structure control law is?developed. Control law stability and robustness are analyzed at the same time.

对于许多应用卫星来说，由于天线、太阳帆板的影响，挠性干扰是个不可避免的问题，本文从工程的角度分析和仿真了带有挠性附件卫星的控制方法。

The variable structure gain is tuned by the fuzzy logic. The designed controller exploits the advantages of CMAC neural network, variable structure control and fuzzy control theory to improve the performance of the system.

利用自适应技术估计了估计误差的大小，减小了系统的不确定性，并利用模糊控制技术调整了变结构增益，改善了系统的性能。

In this article,the writer in combination with the character of variable velocity variable frequency analyzed the principles of transmission system and the request of adjusting velocity in filament yarn twisting machine .

文章分析了弹力丝机传动系统和调速要求，结合变频调速技术的特点，选用艾默生变频器实现调速，简化了传动结构。

Based on the developed variable polarity TIG welding power supply ,it establishes variable polarity TIG welding arc multi-information measuring and processing system by adopting memory oscilloscope,high speed video-recorder?spectrograph?welding arc dynamic analyzer and computer.

以研制的变极性TIG 焊接电源为实验平台，采用记忆示波器、高速摄像仪、光谱分析仪、焊接电弧动态分析仪，建立起变极性TIG焊接电弧多信息测试分析系统，同时采集焊接电流、电弧电压、电弧形态和电弧光谱等重要信息，并基于VisualC++语言开发的软件系统对采集的各种信息进行融合及分析。

Forest ecological benefits index system can divided into two kind from the conception of forest ecological benefits measuration, such as dependent variable of region and stand, independent variable.

本文从森林生态效益计量角度出发，阐述了森林生态效益的定义，指出它与森林资源的相关为第二类相关，并将森林的生态效益的指标体系划分为自变量（区域自变量和林分自变量）和因变量两类。

Based on the requisition of wireless system debugging, this paper develops a novel radio-frequency beaconing. Design method and system constitution of a novel beaconing based on PLL IC PE3336 are given, and the accomplish method of the system's hardware and software arc expounded. The test results show that the beaconing adopted in this method has a reliable and stable frequency conversion features. The more applications in the wireless system find that the users can set necessary frequency conveniently. Especial1, the friendly man-machine interface makes the operation is more flexible. It is as excellent performance-price-ratio beaconing, and as a signal source, it can be used in the research and the debug procession of variable radio-frequency components.

根据无线电数据链系统及部件的调试需要，研制开发了一种新型的以锁相环为核心、由单片机控制的射频信标机；文中给出了基于锁相环芯片PE3336的新型信标机的设计方法与系统组成，阐述了系统硬件及软件的具体实现为法；测试结果表明，利用该方法设计的信标机具有稳定、可靠的变频特性，且各项指标均达到了要求；进一步在某无线电系统中的应用发现，用户可方便地设置所需频点；特别是友好的人机界面，使用户操作更为灵活方便，是一种性能价格比优良的信标机；并可作为信源用于不同的射频部件研制与调试过程中。

Experiments were applied with variable numbers of joined federates and variable length of time advancing step. Major factors that affecting time advancing efficiency of HLA compatible distributed simulation system was concluded based on the comparison and analysis of the experiment results.

通过不同盟员个数和不同仿真推进时间步长下系统推进效率的实验分析，得出限制仿真系统推进效率的主要因素，并结合航天任务物理模型的特点，设计了一种改进的组件交互方案。

To overcome disturbance problem of hedgehopping over the sea, variable structure method is proposed. The central content in this paper is the design of missile altitude control system with variable structure. The research has practical meaning.

不同的干扰因素对导弹高度控制系统的要求是矛盾的，而利用PID控制并不能解决这一矛盾，为此提出了采用变结构高度控制的方法。

Based on the analysis of the unitary split air conditioning system and variable refrigerant volume air conditioning system, considers that the scale-up production is the certain trend of central all-air air conditioning system s and to carry out the design and manufacture of this system in normalization, modularization and series is the key point.

回顾了家用空调和多联机空调系统的发展过程，认为集中式全空气空调系统的规模化生产是发展的必然趋势，其关键是实现规格化、模块化、系列化。

The concept of equivalent rotationally rigidity is offered and the formula of rotationally rigidity is obtained.

主要做了如下几个方面的工作：对伸臂位于顶部的单层框架—筒体模型进行分析，提出了等效转动约束的概念和转动约束刚度的表达式。

Male cats normally do not need aftercare with the exception of the night after the anesthetic.

男猫通常不需要善后除了晚上的麻醉。