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31.
稳频横向塞曼He-Ne激光器作为一种新型光源,具有功率大、频差低、易于相位细分的特点,因而能广泛应用于各种精密测量中.本文介绍了我们研制的稳频横向塞曼激光器,实验结果表明,其激光频率稳定度达4.7×10(-10),再现性达1.8×10(-8). 相似文献
32.
Fan Xuanzhu Tang Jiafu Yan Chongjun Guo Hainan Cao Zhongfa 《Journal of Combinatorial Optimization》2021,42(4):677-699
Journal of Combinatorial Optimization - In medical outpatient services, due to patients’ imbalanced selection for doctors of different levels and for different visiting periods, inefficiency... 相似文献
33.
在考虑产品质量差异与需求不确定双因素影响的基础上,通过构建垂直Nash定价与库存联合博弈模型,研究当线上与线下双渠道销售特定异质产品时,供应链成员如何根据不同的产品类型选择最优分销策略以实现双渠道供应链的共赢。研究结果表明:对于质量差异化低且需求不确定性低的产品类型,供应链成员的共赢分销策略是在线下渠道销售低质量产品并在线上渠道销售高质量产品;对于质量差异化低且需求不确定性高的产品类型,共赢分销策略是在线下销售高质量产品并在线上销售低质量产品;当制造商采用“做坏品”质量差异化策略时,产品类型和分销策略之间的最佳匹配依然保持稳健。 相似文献
34.
战术移动通信网的网络拓扑结构随战场环境的变化而变化,为此网络拓扑结构具有重组的能力,网络拓扑重组后必须进行链路频道的重新分配,文中提出的频道分配技术是在避免同频道干扰条件下任一频道可在全网内多次重复使用,以提高频道的重复利用率,同时分析了该情况下网络至少应拥有的频道数,以保证网络有足够的频道供分配。 相似文献
35.
Guo Y 《China population newsletter》1983,1(2):13-17
Advance results from the 1982 census of China are presented based on a 10 percent sample. Sections are included on age distribution, centenarians, marriage patterns, educational status, and the labor force. Several characteristics of China's population are described in this article, based on a 10% sampling tabulation of the production teams and resident groups of the whole country. Data are included for 100,380,000 people. The proportion of the population aged 0-14 is 33.60%, which marks a decline from figures in the 1964 census (40%). This decline is attributed to family planning and population control efforts. The median age is 22.91 years, which is 2.71 years older than that in the 1964 census. The % of the population aged 15-64 rose from 55.7% in 1964 to 61.5%. The dependency ratio dropped from 79.4% (1964) to 62.6%. There were 3,765 centenarians as of July, 1982; the overwhelming majority live in villages, and most (94.77%) are illiterate or semiliterate. The number of female centenarians is 2.4 times that of males. Marriages are comparatively stable in China. 63.6% of the population aged 15 and over are married, and .59% are divorced. The % of the population remaining single after age 50 is .21% for females, 2.97% for males. The average 1st marriage age is 22.80 years for females and 25.49 years for males. 60.35% of the people have had primary education or above; .44% are college graduates. In 1964, 33.58% of the population illiterate or semiliterate. At present, among people aged 12 and over, 31.90% are illiterate or semiliterate. The rural illiteracy rate is more than twice the urban rate. 51.94% of the total population is employed. Of these, 92.08% are engaged in manual labor. Males exceed females in all professions and occupations. The median age of the employed population is 30.84 years. The level of education among the employed is relatively low: 28.26% are illiterate or semiliterate, and 34.35% have had primary education only. 相似文献
36.
Guo W 《China population newsletter》1983,1(2):28, 27
The China Family Planning Association was set up in May 1980 as a nongovernmental organization under the leadership of the Communist Party of China. Funds come from the government, international organizations, and individual or community donations. 13 branches have been established so far. The Association has contributed to publicity, education, and research: members have given lectures on family planning, genetics, and population theory, and have helped develop contraceptives. The lectures on population problems have been published. In addition, the Association's periodical "Ren Sheng" is published bimonthly, and has a circulation of 125,000. Meeting have been convened for the exchange of information and experience among family planning workers. The Association organized tripartite seminars with IPPF and JOICFP in June and October, 1983. Under the auspices of the Association, 8 trainees have been sent to the David Owen Center in the United Kingdom for a Year's study, and 1 trainee was sent to the London School of Hygiene and Tropical Medicine. The Association was accepted as a full member of the IPPF at the conference held in Nairobi, Kenya, in November, 1983. 相似文献
37.
Optimization Model and Algorithm for Crew Management During Airline Irregular Operations 总被引:4,自引:0,他引:4
Airline irregular operations have long been a realm where human experience and judgement are the most important tools to utilize. Crew management during irregular operations is usually the bottleneck of the whole system-recovering process due to complicated crew schedules and restrictive crew legalities as well as the size and scope of the hub-and-spoke networks adopted by major carriers. A system-wide multi-commodity integer network flow model and a heuristic search algorithm for the above purpose are presented and discussed in this paper. The computational experiences show that the algorithm is efficient enough to solve problems of realistic size and also has the flexibility to accommodate practical business requirements. 相似文献
38.
F. H. Chang H. B. Chen J. Y. Guo F. K. Hwang Uriel G. Rothblum 《Journal of Combinatorial Optimization》2006,11(3):321-339
Consider the problem of partitioning n nonnegative numbers into p parts, where part i can be assigned ni numbers with ni lying in a given range. The goal is to maximize a Schur convex function F whose ith argument is the sum of numbers assigned to part i.
The shape of a partition is the vector consisting of the sizes of its parts, further, a shape (without referring to a particular
partition) is a vector of nonnegative integers (n1,..., np) which sum to n. A partition is called size-consecutive if there is a ranking of the parts which is consistent with their sizes, and all
elements in a higher-ranked part exceed all elements in the lower-ranked part. We demonstrate that one can restrict attention
to size-consecutive partitions with shapes that are nonmajorized, we study these shapes, bound their numbers and develop algorithms
to enumerate them. Our study extends the analysis of a previous paper by Hwang and Rothblum which discussed the above problem
assuming the existence of a majorizing shape.
This research is partially supported by ROC National Science grant NSC 92-2115-M-009-014. 相似文献
39.
郭继明 《重庆师范大学学报(哲学社会科学版)》2018,(3):107-112
许伯建是现当代书坛一位颇有影响的书家,他对郭沫若"伪兰亭"观点曾进行深入辨析,认为"神龙本"更近唐初所存王羲之墨迹,并作出"神龙本"较"定武本"更近真迹的判断;在书学追求上,许主张"神韵出于真实",并以此作为自己攻书的基本原则;其晚年尤醉心于王氏名帖《兰亭集序》,对《兰亭》摹写着力最多,最终成就其雅韵精致的个人书风.许伯建还在传统诗歌创作方面有一定建树,其诗重真情韵致,与其书学重"神韵"的旨趣一脉相承,二者和谐相融、互为促进. 相似文献
40.
唐果 《北京航空航天大学学报(社会科学版)》2018,31(1):50-56
向3000名宁波劳动者发放问卷对宁波公共就业服务质量进行调查,运用模糊综合评价法处理调查数据后发现,劳动者对宁波公共就业服务质量的总体评价是"中等".根据服务质量差距模型构建出宁波公共就业服务质量改善机制.为了提升宁波公共就业服务质量,宁波公共就业服务机构应正确理解劳动者对宁波公共就业服务质量的期望,正确选择公共就业服务设计和制定公共就业服务质量标准,确保按照公共就业服务质量标准提供服务,保证政府公共就业服务传递与承诺相一致. 相似文献