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1.
基于图像处理技术的束流剖面监视系统   总被引:3,自引:1,他引:2       下载免费PDF全文
 介绍了在兰州重离子加速器上利用荧光靶图像获取装置测量并计算束流剖面参数的方法,并建立了图像获取、处理、束流参数计算的实时测量软件系统。该系统具有可靠性好、测量直观、界面友好等优点。  相似文献   
2.
我国医疗费用增长与医疗设备投入的相关性研究   总被引:3,自引:0,他引:3  
近年来我国卫生总费用占GDP的比例增长很快,而在卫生费用结构上则发生政府投入下降和个人支出的上升。本文采集了大量的统计数据,采用统计相关性研究的方法,论证了医疗设备规模的不断扩大是导致医疗费用上升的主要因素之一;医疗设备的快速增长与医院维修费用投入的增长直接相关,而引起医疗设备维修大量投入的主要原因则是故障期内医疗设备的非正常闲置。本文通过对个人卫生费用的上升、医疗设备规模的扩大及其医疗设备维修投入费用增加相关性的分析,说明了在这种关系下,十分有必要研究医院医疗设备维修体系,以在卫生投入和患者权益上达到平衡。  相似文献   
3.
崔晓  程敏  敦帅 《运筹与管理》2022,31(10):61-67
考虑政府补贴、市场化程度、养老机构服务成本、老年人偏好等因素,构建了完全国有化、公私并存的半市场化和完全市场化三种情形下公办和民办养老机构之间的两阶段博弈模型,比较分析了市场化程度对养老机构服务价格制定和服务水平选择的影响,实证讨论了各参数变化对养老机构收益及社会福利的影响。研究表明:完全市场化机制会降低养老机构服务质量,完全国有化机制会陷入社会福利陷阱,探索公私并存的最佳市场化水平才能更好地提高社会福利;适度推进市场化改革,提高养老机构服务水平,降低民办养老机构服务成本,适度提高对民办养老机构的补贴,将有效缓解公办和民办养老机构的不公平竞争;提高老年人支付能力,推进养老机构供给侧结构性改革,将保障机构养老服务的有效供给,促进养老服务业的健康有序发展。  相似文献   
4.
An example of design might be a warehouse floor (represented by a setS) of areaA, with unspecified shape. Givenm warehouse users, we suppose that useri has a known disutility functionf isuch thatH i(S), the integral off iover the setS (for example, total travel distance), defines the disutility of the designS to useri. For the vectorH(S) with entriesH i(S), we study the vector minimization problem over the set {H(S) :S a design} and call a design efficient if and only if it solves this problem. Assuming a mild regularity condition, we give necessary and sufficient conditions for a design to be efficient, as well as verifiable conditions for the regularity condition to hold. For the case wheref iis thel p-distance from warehouse docki, with 1<p<, a design is efficient if and only if it is essentially the same as a contour set of some Steiner-Weber functionf =1 f 1++ m f m ,when the i are nonnegative constants, not all zero.This research was supported in part by the Interuniversity College for PhD Studies in Management Sciences (CIM), Brussels, Belgium; by the Army Research Office, Triangle Park, North Carolina; by a National Academy of Sciences-National Research Council Postdoctorate Associateship; and by the Operations Research Division, National Bureau of Standards, Washington, D.C. The authors would like to thank R. E. Wendell for calling Ref. 16 to their attention.  相似文献   
5.
6.
刘少轩  彭实 《化学教育》2020,41(7):72-75
对中学化学学生实验活动中产生的气体污染物进行测试,得到不同通风条件下化学实验室内部空气污染物的数据。结果表明,中学化学学生分组实验产生的主要气体污染物有苯、甲苯、甲醛、氨气等,实验过程中如不采取任何通风措施,实验室气体污染物的浓度短时间内会急剧升高,所以采取有效措施对实验室内部空气污染物进行消除是非常必要的。目前中学化学实验室配备的通风设备以桌面排风设备为主,相比于自然通风的环境,学生实验时开启桌面排风设备,能够有效降低实验产生的气体污染物浓度。  相似文献   
7.
In the 2nd Science and Technology Basic Plan (2001–2005), the area of nanotechnology and materials is designated one of the four prioritized areas in funding. Following this plan, Ministry of Education, Culture, Sports, Science and Technology (MEXT) and Ministry of Economy, Trade and Industries (METI), the main funding ministries, and their organizations, Japan Society for the Promotion of Science (JSPS), Japan Science and Technology Agency (JST), National Institute for Materials Science (NIMS), RIKEN, New Energy and Industrial Technology Organization (NEDO), and National Institute of Advanced Industrial Science and Technology (AIST) promotes their research programs. Besides, in order to promote interdisciplinary, interorganizational, and international collaboration of researchers, Nanotechnology Support Project (NSP) was started by MEXT in 2002. The project has two missions: informational support and common use facility support. Nanotechnology Researchers Network Center of Japan is responsible for informational support, and 14 universities and national research institutes are responsible for common use facility support.  相似文献   
8.
Summary Selenia Spazio was involved since its beginning, more than twenty years ago, in scientific space missions, like almost all space industries in the world. In fact the European space organizations were mainly devoted to the development of autonomous launchers and to scientific research in the nearby and in the far away space. First programs in which Selenia Spazio had a role, designing and manufacturing space electronic equipment, were scientific satellites and ELDO launchers, followed by COSB and other cosmic research missions. In all these years cosmic physics and related research programs continued to receive technological support and see full involvement by space industry. To speed up publication, the proofs were not sent to the authors and were supervised by the Scientific Committee.  相似文献   
9.
In a sustained development scenario, it is often the case that an investment is to be made over time in facilities that generate benefits. The benefits result from joint synergies between the facilities expressed as positive utilities specific to some subsets of facilities. As incremental budgets to finance fixed facility costs become available over time, additional facilities can be opened. The question is which facilities should be opened in order to guarantee that the overall benefit return over time is on the highest possible trajectory. This problem is common in situations such as ramping up a communication or transportation network where the facilities are hubs or service stations, or when introducing new technologies such as alternative fuels for cars and the facilities are fueling stations, or when expanding the production capacity with new machines, or when facilities are functions in a developing organization that is forced to make choices of where to invest limited funding.  相似文献   
10.
The capacitated arc routing problem (CARP) focuses on servicing edges of an undirected network graph. A wide spectrum of applications like mail delivery, waste collection or street maintenance outlines the relevance of this problem. A realistic variant of the CARP arises from the need of intermediate facilities (IFs) to load up or unload the service vehicle and from tour length restrictions. The proposed Variable Neighborhood Search (VNS) is a simple and robust solution technique which tackles the basic problem as well as its extensions. The VNS shows excellent results on four different benchmark sets. Particularly, for all 120 instances the best known solution could be found and in 71 cases a new best solution was achieved.  相似文献   
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