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1.
运用问卷调查法、文献资料法、数理统计法、逻辑分析法等,对廊坊市城镇居民休闲健身消费的意愿和目的、休闲健身消费的水平、休闲健身消费的方式、和对影响廊坊城镇居民休闲健身消费的因素等问题进行调查分析。在现状调查分析的基础上,有针对性地提出一些扩大廊坊市城镇居民休闲健身消费的合理建议。  相似文献   

2.
一、可持续发展战略的提出全球人口的增长、经济的发展导致了一系列环境问题,如全球变暖、臭氧层破坏、生物多样性在消失等,这些问题对人类的健康和生存环境产生了极为不利的影响。人类生存和经济发展是以消费资源和消耗能源为基础的。长  相似文献   

3.
论文根据对广西农村消费市场的随机抽样调查及统计资料的分析,概括了广西农村居民消费现状的基本情况:广西农村居民的需求趋于稳定;消费结构有所提高,但消费层次仍然偏低;求实求利的消费动机;电视、人际、商品广告宣传单为主要途径的信息传播方式;家庭共同决策、从众的消费模式;预期消费热点商品主要是家用电器、摩托车和农用车等;消费维权意识有所提高;"家电下乡"的政策有待进一步加强宣传推广。  相似文献   

4.
文章分析了制约我国住房消费需求的各种因素,并提出了扩大住房消费需求,促进经济增长的初步对策。  相似文献   

5.
旅游消费作为人类社会的一种高级消费形态,具有很强的层次性特征。在详细介绍多层次旅游消费含义的基础上,深入阐述了我国多层次旅游消费形成的客观原因,最后指出加快推进我国多层次旅游消费发展的战略意义。  相似文献   

6.
7月15日至8月15日,位于北京航天城内的中国航天员中心开展了女性头低位卧床实验。这是我国首次组织以女性在模拟失重环境下的生理变化特点为研究目标的卧床实验。研究者希望通过本次实验,获得女性在太空失重环境中生理活动的基本变化情况,并验证相应防护方法的有效性和可靠性。此次实验为探索我国交会对接任务女性在轨失重生理效应的规律特点,研究女性在轨防护措施应用原则及评估防护效果提供了实验数据。参加本研究的所有志愿者均为北京市各高校的在校女大学生。在近百名的报名者中,经过初筛、复查等数轮包括各种生理和心理测试后,共有22名志愿者进入最后的卧床实验。实验中,所有志愿者均需在床上完成吃、喝、拉、撒等各种日常活动。本次实验的顺利完成将加强对女性在太空中生理变化特点的认识,为我国首次将女性航天员送入太空奠定基础。  相似文献   

7.
发挥卫星遥感优势促进可持续发展   总被引:1,自引:0,他引:1  
一、可持续发展战略的提出全球人口的增长、经济的发展导致了一系列环境问题,如全球变暖、臭氧层破坏、生物多样性在消失等,这些问题对人类的健康和生存环境产生了极为不利的影响。人类生存和经济发展是以消费资源和消耗能源为基础的。长期以来,经济的发展是以资源的过度开发和能源的过度消耗为代价的,同时对环境和生态造成了污染和破坏。照此状况发展下去,几十至几百年后,人类将无地可耕,无矿可采,无能(矿物能源)可用,环境恶化、生态退化,人类的生存和生活将受到严重威胁。基于越来越严重的全球人口、资源和环境问题,1972…  相似文献   

8.
空间适应性综合症的种种表现沈羡云唐承业人类在整个进化过程中都是处于1g的环境中,体内的各个生理系统产生了适应1g环境的生理变化。航天的过程中,航天员从长期适应的重力环境突然进入到失重环境,人体内的生理系统和心理就会产生一系列适应失重环境的变化。这种适...  相似文献   

9.
偏好是影响消费者选择啤酒的一个关键点。调查分析发现:口味口感、品牌、价格、购买便利是桂林市场消费者最关注的四个啤酒消费偏好因素,此外,广告、促销、包装,安全等也对其啤酒消费偏好有一定影响,同样不容企业忽视。  相似文献   

10.
为了解当前大学生家庭经济状况和消费状况 ,为学校制定助学办法提供科学依据、引导大学生树立正确合理的健康消费观念 ,近期我们以问卷调查的方式对我校大学生进行了家庭经济状况及消费状况方面的调查。调查表明 ,我校大学生贫困比例达到 30 %左右 ,大学生消费观念总体上是健康合理的 ,但同时也存在着一些不健康的消费观念。  相似文献   

11.
A string moving with geostationary angular velocity in its radial relative equilibrium configuration around the Earth, reaching from the surface of the Earth far beyond the geostationary height, could be used as track for an Earth to space elevator. This is an old dream of mankind, originating about 100 years ago in Russia. Besides the question of feasibility from a technological point of view also the question concerning the stability of such a configuration has not yet been completely solved. Under the assumption that a proper material (carbon nanotubes) is available, making the connection possible technologically, we address the question of existence and stability of the radial relative equilibrium of a tapered string on a circular geosynchronous trajectory around the Earth, reaching from the surface of the Earth far beyond the geostationary height.  相似文献   

12.
In this paper, we analyze the illumination conditions, the thermal regime, and the possibility of deposits of volatile compounds existing in the vicinity region (NSR S5 region) near the southern pole of the Moon. It has been found that there are no permanently shadowed zones near the Scott crater and the NSR S5 region, though the temperature conditions allow the of compounds such as CH3OH, SO2, NH3, CO2, H2S, C2H4, and water to remain stable relative to evaporation for a long time (≥1 Gyr). It has been also shown that compounds like CO and CH4 cannot stably exist in these regions.  相似文献   

13.
The results of an investigation of the distribution of plasma pressure, pressure gradients, and magnetic field near the equatorial plane in the plasma ring surrounding the Earth under magneto-quiet conditions are presented. Observational data obtained during the international THEMIS mission are used. The picture of the distribution of transverse-current density near the equatorial plane was obtained under assumption of observing the magnetostatic balance condition at geocentric distances from 6 to 12R E. In estimating the integral transverse current it was accepted that in daytime sector the magnetic-field minima on magnetic field lines are not localized in the equatorial plane. Estimates of the integral transverse current were obtained, which demonstrate the possibility of closing nighttime transverse currents at geocentric distances of up to ~12R E inside the magnetosphere, which form a high-latitudinal continuation of the ring current.  相似文献   

14.
对老年人体育锻炼负荷量监控方法的探讨   总被引:2,自引:0,他引:2  
通过对老年人体育锻炼活动的情况进行相关调查,发现目前老年人体育锻炼中存在一些误区。因此本文针对这些现实情况提出,应根据实际情况运用一些简单易行的方法来对老年人体育锻炼实施医务监督,达到提高老年人体育锻炼的科学性。  相似文献   

15.
The paper has studied the accuracy of the technique that allows the rotational motion of the Earth artificial satellites (AES) to be reconstructed based on the data of onboard measurements of angular velocity vectors and the strength of the Earth magnetic field (EMF). The technique is based on kinematic equations of the rotational motion of a rigid body. Both types of measurement data collected over some time interval have been processed jointly. The angular velocity measurements have been approximated using convenient formulas, which are substituted into the kinematic differential equations for the quaternion that specifies the transition from the body-fixed coordinate system of a satellite to the inertial coordinate system. Thus obtained equations represent a kinematic model of the rotational motion of a satellite. The solution of these equations, which approximate real motion, has been found by the least-square method from the condition of best fitting between the data of measurements of the EMF strength vector and its calculated values. The accuracy of the technique has been estimated by processing the data obtained from the board of the service module of the International Space Station (ISS). The reconstruction of station motion using the aforementioned technique has been compared with the telemetry data on the actual motion of the station. The technique has allowed us to reconstruct the station motion in the orbital orientation mode with a maximum error less than 0.6° and the turns with a maximal error of less than 1.2°.  相似文献   

16.
本文介绍了“三位一体”教育模式的内容,描述亍我们实施该模式所采取的措施及取得的成效。实践表明,“三位一体”教育模式能够提高学生的综合素质,为学生毕业后的发展打下坚实基础,对教育模式的改革具有一定的指导意义。  相似文献   

17.
电阻式传感器的核心部件——电阻应变计是目前最常用的应力分析的敏感元件。也常用于测量力、压力、扭矩和加速度等物理量。作者简要回顾了电阻应变计的发展历史,介绍了电阻应变计的结构、分类及现状,展望了电阻式传感器的前景。  相似文献   

18.
The results of modeling the dynamics of the Space Radiotelescope are presented. The results of ground-based vibration-dynamic tests are used to validate the calculation models and estimate the damping levels. The dynamic distortions of the reflecting surface caused by the operation of the pointing mechanism of the high-gain antenna are estimated.  相似文献   

19.
The possibility of the spacecraft insertion into the system of operational heliocentric orbits has been analyzed. It has been proposed to use a system of several operational heliocentric orbits. On each orbit, the spacecraft makes one or more revolutions around the Sun. These orbits are characterized by a relatively small perihelion radius and relatively high inclination, which allows one to investigate the polar regions of the Sun. The transition of the spacecraft from one orbit to another has been performed using an unpowered gravity assist maneuver near Venus and does not require the cruise propulsion operation. Each maneuver transfers the spacecraft into the sequence of operational heliocentric orbits. We have analyzed several systems of operational heliocentric orbits into which the spacecraft can be inserted by means of the considered transportation system with electric propulsion (EP). The mass of the spacecraft delivered to these systems of operational orbits has been estimated.  相似文献   

20.
火箭推进剂液体晃动关机响应的数值仿真   总被引:4,自引:0,他引:4  
本文采用VOF方法对火箭发动机关机阶段所引起的液体晃动进行了数值仿真,以氧化剂贮箱为例,得到了贮箱无阻尼环和带阻尼环时的晃动仿真图和液体质心变化曲线,检验了VOF方法处理碎波的能力。  相似文献   

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