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Heisenberg Group and Energy-Momentum Conservative Law in de-Sitter Spaces—— In Memory of the 100th Anniversary of Einstein's Special Relativity and the 70th Anniversary of Dirac's de-Sitter Spaces 被引量:9
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作者 LU Qi-Keng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期389-392,共4页
In 1935 Dirac established the physical wave equations in the de-Sitter spaces but neither energy-momentum operators nor their conservative laws were given. In this article it is proved that in the de-Sitter group ther... In 1935 Dirac established the physical wave equations in the de-Sitter spaces but neither energy-momentum operators nor their conservative laws were given. In this article it is proved that in the de-Sitter group there is a subgroup group isomorphic to the Heisenberg group and the generators of this groups are the energy-momentum operators which obey a conservative law. 展开更多
关键词 energy-momentum conservation Heisenberg grup de-Sitter space
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Multi-scaled simulation of latticed frames considering bending collapse of pipes 被引量:7
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作者 刘海锋 LOU Rong +1 位作者 LUO Yao-zhi DANG Hui-xue 《Journal of Chongqing University》 CAS 2012年第4期167-176,共10页
To consider the bending collapse of the pipes in the latticed frames, based on the multi-scale simulation, the collapsed parts of the pipe are meshed by the shell elements as micro-scaled models, and the other parts a... To consider the bending collapse of the pipes in the latticed frames, based on the multi-scale simulation, the collapsed parts of the pipe are meshed by the shell elements as micro-scaled models, and the other parts are meshed by beam elements macro-models. The incremental displacement constraint equations for the nodes on the section between the two models are established based on the plane section premise of classical beam theory. The method to introduce the constraint equations is derived based on the Updated Largrangian method. The location of the micro-model is predicted by the stress field of the beam element, and the length of the collapsed part is adjusted by the plastic energy in the micro model. Several examples are included to illustrate the efficiency and accuracy of this method. 展开更多
关键词 multi-scaled simulation latticed frames bending collapse plane section premise
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Characteristics of Chinese male patients with breast cancer:summary of the published papers 被引量:1
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作者 Liangping Xia Zhongyu Yuan +5 位作者 Xi Wang Jiehua He Bei Zhang Guifang Guo Feifei Zhou Fang Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第6期311-315,共5页
Objective:The extremely low incidence of male breast cancer (MBC) leads to lack of prospective randomized phase III studies worldwide. Especially in China,all studies on Chinese patients with MBC were based on small s... Objective:The extremely low incidence of male breast cancer (MBC) leads to lack of prospective randomized phase III studies worldwide. Especially in China,all studies on Chinese patients with MBC were based on small sample size and single institute experience. The aim of this study was to provide overall view of characteristics of Chinese patients with MBC by means of summarizing all related papers published in Chinese journals. Methods: An online search was made in CBM,VIP,CNKI,and CBA databases to find all published articles of interest on Chinese patients with MBC. And eight subjects including the proportion of MBC in all breast cancer,age,tumor location,clinical stages,pathological subtypes,treatment modalities,ER/PR expression,and 5-year survival rate were selected to calculate the proportion and their 95% interval confidence. Results: There were 122 papers with 2584 patients enrolled. The basic features of Chinese patients with MBC included:(1) MBC only with a proportion of 1.06% of all the breast cancer; (2) The mean age at diagnosis was 57.6 years old; (3) Tumor mainly located in the areolar region (74.83%) with obvious nipple and/or skin involvement; (4) Nearly 62.62% patients were in early stage before accepting treatment; (5) Infiltrating ductal carcinoma accounted for 79.05% of all pathological subtypes; (6) ER/PR expression rate was 65.86%; (7) Radical resection was up to 86.06% in all surgical modalities; (8) The 5-year survival rate was 57.33%. Conclusion: The results showed in this study were an overall view of Chinese patients with MBC whose characteristics were similar to that reported in the West. Though this study provided a little bit stronger confidence than a single study collected in this paper,studies with more powerful evidence are urgently demanding in China. 展开更多
关键词 male breast cancer clinicopathological characteristic treatment modalities PROGNOSIS Chinese patients DATABASE SUMMARY
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What to understand in interpretation: Meaning or sense?
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作者 袁颖磊 张添琼 《Sino-US English Teaching》 2007年第8期72-75,共4页
Source language perception is the beginning and also the most unobservable stage of interpretative activity. According to ESIT, it is the sense that constitutes a communicative intention. Sense cohort theory and requi... Source language perception is the beginning and also the most unobservable stage of interpretative activity. According to ESIT, it is the sense that constitutes a communicative intention. Sense cohort theory and requirement equation upon interpreter shall be presented in the paper by combining perspectives from psycholinguistics and cognitive science. 展开更多
关键词 SL perception SENSE sense cohort theory interpretation requirements equations
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Multimodality approach for locally advanced esophageal cancer 被引量:12
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作者 Khaldoun Almhanna Jonathan R Strosberg 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第40期5679-5687,共9页
Carcinoma of the esophagus is an aggressive and lethal malignancy with an increasing incidence worldwide.Incidence rates vary internationally,with the highest rates found in Southern and Eastern Africa and Eastern Asi... Carcinoma of the esophagus is an aggressive and lethal malignancy with an increasing incidence worldwide.Incidence rates vary internationally,with the highest rates found in Southern and Eastern Africa and Eastern Asia,and the lowest in Western and Middle Africa and Central America.Patients with locally advanced disease face a poor prognosis,with 5-year survival rates ranging from 15%-34%.Recent clinical trials have evaluated different strategies for management of locoregional cancer;however,because of stage migration and changes in disease epidemiology,applying these trials to clinical practice has become a daunting task.We searched Medline and conference abstracts for randomized studies published in the last 3 decades.We restricted our search to articles published in English.Neoadjuvant chemoradiotherapy followed by surgical resection is an accepted standard of care in the United States.Esophagectomy remains an essential component of treatment and can lead to improved overall survival,especially when performed at high volume institutions.The role of adjuvant chemotherapy following curative resection is still unclear.External beam radiation therapy alone is considered palliative and is typically reserved for patients with a poor performance status. 展开更多
关键词 Esophageal cancer ADJUVANT NEOADJUVANT CHEMOTHERAPY CHEMORADIATION
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How to Write English Titles, Abstract and Key Words for Folklore Papers: Practice and Analysis
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作者 马建忠 马伟 《Sino-US English Teaching》 2006年第6期68-71,75,共5页
Folklore research entails field trips, serve as secondary role. Writing of title, abstract and while textual study and circumstantial investigation merely keywords for folklore papers differs from that of other types ... Folklore research entails field trips, serve as secondary role. Writing of title, abstract and while textual study and circumstantial investigation merely keywords for folklore papers differs from that of other types of articles. Proceeding from writing strategies and linguistic features, the authors intend to share their experience with fellow researchers. 展开更多
关键词 folklore research papers titles ABSTRACTS key words writing strategies linguistic features
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A QoS-aware scheduling algorithm for combined-input-crosspoint-queued switch
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作者 徐宁 WANG Xue-shun 《Journal of Chongqing University》 CAS 2012年第4期161-166,共6页
In this paper, we study the quality of service requirement and guaranteed-rate scheduling problem for combined-input-crosspoint-queued (CICQ) switches. Using crosspoint buffers between input queues and output ports, t... In this paper, we study the quality of service requirement and guaranteed-rate scheduling problem for combined-input-crosspoint-queued (CICQ) switches. Using crosspoint buffers between input queues and output ports, the input and output scheduling can be decoupled in CICQ switches. Here we propose a new guaranteed-rate scheduling algorithm which is divided seperately into input and output scheduling. Simulation results show that our algorithm can perform better than existing scheduling schemes in both packet loss and jitter control. 展开更多
关键词 combined-input-crosspoint-queued switch guaranteed-rate scheduling low jitter quality of service
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Seismic performance testing of reinforcement concrete frames strengthened with Y-eccentrically brace
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作者 王大鹏 YU An-lin XUE Li-ming 《Journal of Chongqing University》 CAS 2012年第4期151-160,共10页
Two single-storey single-span reinforcement concrete (RC) frame structures strengthened with Y-eccentrically brace were designed and manufactured to be 1/3 scale. The pseudo-dynamic testing method was used to study ... Two single-storey single-span reinforcement concrete (RC) frame structures strengthened with Y-eccentrically brace were designed and manufactured to be 1/3 scale. The pseudo-dynamic testing method was used to study the mechanical characteristics and the seismic performance under E1-Centro earthquake action with different peak acceleration adjusted by China's Code for Seismic Design of Buildings. The test results indicate that RC frame structures strengthened with Y- eccentrically steel brace present perfect seismic performance under strong earthquake action owing to the good ductility, strong bearing capability and fine energy absorbing capability provided by energy dissipation element and high lateral stiffness provided by diagonal braces. The seismic performance is also affected by the length of outsourcing steel at the joint between energy dissipation element of eccentric steel brace and RC frame beam. The joint should be considerably designed to make sure that shear failure can firstly occur in energy dissipation element. 展开更多
关键词 Y-eccentrically steel brace energy dissipation element pseudo-dynamic test seismic performance shear failure
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Effects of surface modification by Ni, Ti and B on electrochemical properties of Mg_(1.8)Cu_(0.2)Ni hydrogen storage alloy
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作者 焦晓燕 WANG Chang-qing +1 位作者 ZHAO Na ZHU Gui-qin 《Journal of Chongqing University》 CAS 2012年第4期177-182,共6页
Amorphous alloy Mg1.8Cu0.2Ni was successfully prepared by mechanical alloying (MA) and a series of (n-x)Ni- x(Ti+B) composites were synthesized by MA. The electrochemical properties of Mgl.8Cu0.2Ni coated by Ni... Amorphous alloy Mg1.8Cu0.2Ni was successfully prepared by mechanical alloying (MA) and a series of (n-x)Ni- x(Ti+B) composites were synthesized by MA. The electrochemical properties of Mgl.8Cu0.2Ni coated by Ni, Ti and B were studied by cyclic charge-discharge, linear polarization curve, and hydrogen diffusion coefficient experiments. Experimental results indicate that Mg1.8Cu0.2Ni-[0.9Ni0.6(Ti+B)] composite which was MA 30 h exhibited the best performance and its initial discharge capacity arrived to 714.1 mAh/g. After 30 cycles the discharge capacity was above 530 mAh/g, which was much higher than that of Mg1.8Cu0.2Ni. And after 100 cycles it holded still 442.1 mAh/g. On all accounts, after modification by Ni, Ti and B, the initial discharge capacity and high-rate discharge ability of the electrode were evidently increased. At the same time, the cycle performance was also improved significantly. 展开更多
关键词 hydrogen storage alloy mechanical alloying method surface modification MgNi-NiTiB
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Reducing sugars production from pretreated rapeseed straw
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作者 肖弥彰 SHIN Hyun-jae DONG Qiu-hua 《Journal of Chongqing University》 CAS 2012年第4期183-194,共12页
Lignocellulosic biomass, being treated only with ammonia, treated with ammonia and then autoclaved, and treated with white-rot fungi after being mechanically chipped, were carried out to access the effects of lignocel... Lignocellulosic biomass, being treated only with ammonia, treated with ammonia and then autoclaved, and treated with white-rot fungi after being mechanically chipped, were carried out to access the effects of lignocellulose degradation by white-rot fimgi cultured on rapeseed straw. Fourier transform infrared spectroscopic analysis was used to show that the white-rot fungus Bjerkandera sp. strain increase the susceptibility of straw to enzymatic saccharification by modifying the lignin component, revealing the effect of these pretreatments on enzymatic saccharification. Reducing sugar production from straws pretreated by ammonia/mechanical chipping/fungi degradation was 29.80% higher than the samples treated with ammonia/autoclaving, indicating an effective degradation of phenolic compounds. After ammonia pretreatment 41% of the straw was converted to RS (reducing sugars) (glucose 50%). After 5 weeks pretreatment with the white-rot fungus, 54.8% of rapeseed straw was further converted to RS, 74% of which was glucose; while only 12% of the control straw was converted (glucose 42%). The white-rot fungus Bjerkandera sp. strain degraded rapeseed straw preferentially at the early stage (before 20 d), and the degradation selectivity was 0.181 1 (cellulose), 0.364 1 (hemicellulose), and 0.454 8 (lignin), suggesting that removal of the phenolic barriers enhanced reducing sugar yield, and the efficiency of fungal pretreatment was comparable with that after alkali treatment, resulting a higher proportion of glucose in the hydrolysates. 展开更多
关键词 PRETREATMENT reducing sugars white-rot fungi Fourier transform infrared
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On construction waste disposal in Chongqing
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作者 廖奇云 ZHONG Guo-yi +1 位作者 TAO Yan-yu JIA Shun 《Journal of Chongqing University》 CAS 2012年第4期195-202,共8页
With rapid development of the construction industry in China, lots of construction materials are being widely reused. Meanwhile, more and more materials for building remover or demolition enter into the environment as... With rapid development of the construction industry in China, lots of construction materials are being widely reused. Meanwhile, more and more materials for building remover or demolition enter into the environment as a result. However, China is facing big building garbage pollution, with simple disposal methods and low efficiency, which urgently needs to be improved. The paper takes Chongqing as an example to illustrate existing problems in this field and then puts forward corresponding countermeasures from the aspects of economy, technology, management and policy, aiming at enhancing the level of construction waste disposal in China. 展开更多
关键词 construction waste COUNTERMEASURE CHONGQING DISPOSAL
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Rock strength interval analysis using theory of testing blind data and interval estimation 被引量:1
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作者 田森 陈建宏 董陇军 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期168-177,共10页
The concepts of rock strength intervals are presented in this work, furthermore, central values of intervals and their corresponding credibility are provided using two-case study based on blind data theory and fuzzy i... The concepts of rock strength intervals are presented in this work, furthermore, central values of intervals and their corresponding credibility are provided using two-case study based on blind data theory and fuzzy interval estimation. 60 granite specimens are first tested, the compressive strength interval and tensile strength interval are [ 103.68, 219.6 l ] and [7.53, 11,86] MPa, while the tested mean values of compressive strength and tensile strength are 152.86 and 10.14 MPa, the credibilities are less than 58.4% and around 70.4%, respectively, the credibility of shear strength is between 40% and 60%. Then 70 other rock specimens are designed and tested, the similar conclusions can be reached. The results show that the conventional definite values are the particular values within the intervals, and the credibility of them often fails to reach the high-precision engineering requirement. The results demonstrate the feasibility and application potential of this proposed algorithm for the engineering practice. The references for engineering value selection of rock strength under different credibility or according to frequency distribution of central values are provided to increase the reliability and precision of calculation. 展开更多
关键词 rock strength interval uniaxial compressive strength uniaxial tensile strength shear strength blind data interval theory
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Changes in Argumentation Performance:Effects of Teacher-Student Collaborative Assessment
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作者 Xiaoyan XU Yuexin ZHONG Zimeng SHAO 《Chinese Journal of Applied Linguistics》 2022年第4期491-509,612,共20页
This paper compares the effectiveness of one-semester-long instruction of teacher-student collaborative assessment(TSCA)and trained peer review assessment(TPRA).Dependent variables include occurrence of structural ele... This paper compares the effectiveness of one-semester-long instruction of teacher-student collaborative assessment(TSCA)and trained peer review assessment(TPRA).Dependent variables include occurrence of structural elements of the simplified Toulmin model,and improvement of argumentation substance which refers to the quality of reasoning reflected in Toulmin structural elements.Eighty-one sophomore English majors from TSCA group(n=41)and TPRA group(n=40)were asked to construct two argumentative essays at both the beginning and the end of the semester.The results reveal that the TSCA group produced significantly more counterargument claims and rebuttal data.Additionally,the TSCA group significantly outperformed TPRA group in constructing stronger counterargument claim,rebuttal claim and rebuttal data. 展开更多
关键词 structural elements Toulmin model argumentation substance teacher-student collaborative assessment peer review English writing
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Globalization or Isolation?—— Ricardo's Model
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作者 Eizo Kinoshita 《Chinese Business Review》 2011年第10期939-947,共9页
Through the attempt to clarify justifiable economic circumstances where a policy of globalization and/or a policy of national isolation is proven valid, the author revealed in this thesis that there are two such econo... Through the attempt to clarify justifiable economic circumstances where a policy of globalization and/or a policy of national isolation is proven valid, the author revealed in this thesis that there are two such economic phases: An economy where the theory of comparative advantage, proposed by David Ricardo, is applicable, and an economy where the theory is not applicable. The author applied his original approach to prove the validity of Ricardo's comparative advantage theory, and found that the theory can be justified only when a macro economy is in the primal problem phase, where a policy of globalization is effective. It is a necessary and sufficient condition for the theory to be valid. In other words, Ricardo's theory of comparative advantage is not applicable when a macro economy is in the dual problem phase, where a policy of national isolation, instead of that of globalization, is valid. The primal problem phase and the dual problem phase of a macro economy, called in this thesis by the author, are a version of an expression quite common in OR (operations research). 展开更多
关键词 Ricardo's model GLOBALIZATION ISOLATION
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Verifying Ricardo's Model--Whether TPP is Right or Wrong?
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作者 Eizo Kinoshita 《Journal of Mathematics and System Science》 2013年第1期31-40,共10页
Through his attempt to clarify justifiable economic circumstances where a policy of globalization and/or a policy of national isolation is proven valid, the author reveals in this thesis that there are two such econom... Through his attempt to clarify justifiable economic circumstances where a policy of globalization and/or a policy of national isolation is proven valid, the author reveals in this thesis that there are two such economic phases: an economy where the theory of comparative advantage, proposed by David Ricardo, is applicable, and an economy where the theory is not applicable. The author applied his original approach to prove the validity of Ricardo's comparative advantage theory, and found that the theory can be justified only when a macro economy is in the thetical economic phase, where a policy of globalization is effective. It is a necessary and sufficient condition for the theory to be valid. In other words, Ricardo's theory of comparative advantage is not applicable when a macro economy is in the antithetical economic phase, where a policy of national isolation, instead of that of globalization, is valid. The thetical economic phase and the antithetical economic phase of a macro economy, referred to in this thesis by the author, are a version of an expression quite common in OR (operations research). 展开更多
关键词 Ricardo's model GLOBALIZATION isolation.
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Some Remarks On E'-matrices
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作者 LI Jian-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期40-45,共6页
The class of E'-matrices introduced in [4] is a subclass of Q0-matrices whose proper principal submatrices are Q--matrices. In this paper, we investigate the relation of the class E' to other known matrix classes an... The class of E'-matrices introduced in [4] is a subclass of Q0-matrices whose proper principal submatrices are Q--matrices. In this paper, we investigate the relation of the class E' to other known matrix classes and obtain a series of necessary and sufficient conditions for E'-matrices. 展开更多
关键词 linear complementarity problem E'-matrix irreducible matrices almost E-matrices
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电力市场中计算输电电价的一种新方法 被引量:28
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作者 任震 吴国玥 黄雯莹 《中国电机工程学报》 EI CSCD 北大核心 2003年第1期37-40,170,共5页
该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合... 该文基于边际成本理论,提出了一种计算输电电价的新方法,在保留边际成本定价中的经济信息的同时,综合考虑了无功电价,又考虑了电网的年收支平衡,最后,通过潮流跟踪法,确定有功、无功电价及固定成本在各个用户间的分配,使定价模型更加合理、完善。经IEEE6节点系统算例证明,该文所提的模型和算法是正确而有效的,具有重要的理论意义和工程实际价值,特别是对于在厂网分开后电网建设以及维护电网稳定的资金筹措有相当的指导价值。 展开更多
关键词 电网 无功功率 边际成本理论 潮流计算 电力市场 输电电价
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Classifying R-dual Sequence in the Abstract Frame Theory
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作者 吴国昌 王澜峰 李登峰 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第3期378-383,共6页
In this paper,two operators are defined,and their underlying properties are found,then the R-dual relationship is classified from the aspect of the operators defined.Furthermore,the commutability of the bases of const... In this paper,two operators are defined,and their underlying properties are found,then the R-dual relationship is classified from the aspect of the operators defined.Furthermore,the commutability of the bases of constructing R-dual sequence is discussed.In particular,SR-dual sequence is defined and is clarified.At last an example is given. 展开更多
关键词 the frame theory R-dual sequence SR-dual sequence COMMUTABILITY
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Research on the mental health condition of the elderly under the institution for the aged
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作者 GAO Jie CAI Guomei XUE Yingying 《International English Education Research》 2018年第3期7-10,共4页
After entering the aging society, the pension problem of the elderly population has become an urgent problem to be solved in the current and future social life of our country. The rapid growth of the elderly populatio... After entering the aging society, the pension problem of the elderly population has become an urgent problem to be solved in the current and future social life of our country. The rapid growth of the elderly population will inevitably bring about changes in the family structures, which leads to the inevitable development trend of the old-age pension institutions for the elderly. With the progress of the society, the needs of the elderly for the old-age pension are not only satisfied with their life care, but also with the spiritual needs. Based on the planning contents of the 13th Five-Year Plan for the elderly, on the basis of the Maslow's demand level theory, this paper analyzes the present status of the services of the institutions for the elderly to the elderly psychological health, and concludes that the needs of the emotions of the elderly, the needs of their self-esteem, the needs of their self-realization and their physiological needs of the elderly and their security needs are equally important. 展开更多
关键词 Institutional endowment the elderly mental health
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从古文到有用文字:《古文关键》之“关键”与经典重塑
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作者 慈波 《北京大学学报(哲学社会科学版)》 CSSCI 北大核心 2024年第1期119-127,共9页
吕祖谦在突破《精骑》片段选文的困境后,于淳熙元年完成选录古文经典的《古文关键》,成为评点类选本的开山之作。《丽泽文说》与《总论》互有出入,都是吕祖谦与弟子谈文之际见解的笔录,但与《古文关键》没有直接附属关系。《古文关键》... 吕祖谦在突破《精骑》片段选文的困境后,于淳熙元年完成选录古文经典的《古文关键》,成为评点类选本的开山之作。《丽泽文说》与《总论》互有出入,都是吕祖谦与弟子谈文之际见解的笔录,但与《古文关键》没有直接附属关系。《古文关键》之前所附的《要法》,则是《总论》的精简整理本,反映了弟子笔录的条目与《古文关键》相配合的过程。《古文关键》创造性地将标抹符号与文章剖析相结合,开创了要法、总评、尾评、夹评相结合的评注形式,提揭大量时文结构术语,引领了文章评点风气。其立柱一说,是“段子”文字在文章结构上的形式呈现,构成八股文“四比”体式的滥觞。吕祖谦根据科举应试需要,标举“关键”,强调格法,以评点的形式,将古文经典重塑为“有用文字”。狭义的“关键”为章句组织方面的紧要之处与其间奥妙之法,广义的“关键”即“文诀”。吕祖谦文章学思想的新锐性与系统性,使他成为文章学成立时期的中心人物。 展开更多
关键词 《古文关键》 《总论》 《要法》 《丽泽文说》 吕祖谦
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