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Cosmology-Independent Photon Mass Limits from Localized Fast Radio Bursts by Using Artificial Neural Networks
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作者 冉景遇 王宝 魏俊杰 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期177-183,共7页
A hypothetical photon mass m_(γ) can produce a frequency-dependent vacuum dispersion of light, which leads to an additional time delay between photons with different frequencies when they propagate through a fixed di... A hypothetical photon mass m_(γ) can produce a frequency-dependent vacuum dispersion of light, which leads to an additional time delay between photons with different frequencies when they propagate through a fixed distance. The dispersion measure and redshift measurements of fast radio bursts(FRBs) have been widely used to constrain the rest mass of the photon. However, all current studies analyzed the effect of the frequency-dependent dispersion for massive photons in the standard ΛCDM cosmological context. In order to alleviate the circularity problem induced by the presumption of a specific cosmological model based on the fundamental postulate of the masslessness of photons, here we employ a new model-independent smoothing technique, artificial neural network(ANN), to reconstruct the Hubble parameter H(z) function from 34 cosmic-chronometer measurements.By combining observations of 32 well-localized FRBs and the H(z) function reconstructed by ANN, we obtain an upper limit of m_(γ) ≤ 3.5 × 10^(-51)kg, or equivalently m_(γ) ≤ 2.0 × 10^(-15)eV/c^(2)(m_(γ) ≤ 6.5 × 10^(-51)kg, or equivalently m_(γ) ≤ 3.6 × 10^(-15)eV/c_(2)) at the 1σ(2σ) confidence level. This is the first cosmology-independent photon mass limit derived from extragalactic sources. 展开更多
关键词 DISPERSION LIMIT independENT
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A Constrained Local Neighborhood Approach for Efficient Markov Blanket Discovery in Undirected Independent Graphs
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作者 Kun Liu Peiran Li +4 位作者 Yu Zhang JiaRen Ming Li Xianyu Wang Cong Li 《Computers, Materials & Continua》 SCIE EI 2024年第8期2535-2555,共21页
When learning the structure of a Bayesian network,the search space expands significantly as the network size and the number of nodes increase,leading to a noticeable decrease in algorithm efficiency.Traditional constr... When learning the structure of a Bayesian network,the search space expands significantly as the network size and the number of nodes increase,leading to a noticeable decrease in algorithm efficiency.Traditional constraint-based methods typically rely on the results of conditional independence tests.However,excessive reliance on these test results can lead to a series of problems,including increased computational complexity and inaccurate results,especially when dealing with large-scale networks where performance bottlenecks are particularly evident.To overcome these challenges,we propose a Markov blanket discovery algorithm based on constrained local neighborhoods for constructing undirected independence graphs.This method uses the Markov blanket discovery algorithm to refine the constraints in the initial search space,sets an appropriate constraint radius,thereby reducing the initial computational cost of the algorithm and effectively narrowing the initial solution range.Specifically,the method first determines the local neighborhood space to limit the search range,thereby reducing the number of possible graph structures that need to be considered.This process not only improves the accuracy of the search space constraints but also significantly reduces the number of conditional independence tests.By performing conditional independence tests within the local neighborhood of each node,the method avoids comprehensive tests across the entire network,greatly reducing computational complexity.At the same time,the setting of the constraint radius further improves computational efficiency while ensuring accuracy.Compared to other algorithms,this method can quickly and efficiently construct undirected independence graphs while maintaining high accuracy.Experimental simulation results show that,this method has significant advantages in obtaining the structure of undirected independence graphs,not only maintaining an accuracy of over 96%but also reducing the number of conditional independence tests by at least 50%.This significant performance improvement is due to the effective constraint on the search space and the fine control of computational costs. 展开更多
关键词 Bayesian network structure learning Markov blanket conditional independence
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Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H
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作者 Jianzhao Yin Yuhong Chao +2 位作者 Haoyu Yin Hongyun Shi Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2024年第2期385-398,共14页
By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)... By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma. 展开更多
关键词 Carbon oxygen and hydrogen isotopes ORIGIN independent tellurium deposit The Qinghai–Xizang Plateau
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Are cities greener because of innovation?Independent innovation policy and green economic efficiency
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作者 Zhuoji Zheng Xueqin Li +3 位作者 Mengjie Yu Yuan Li Xianfeng Han Yuping Yin 《Chinese Journal of Population,Resources and Environment》 2024年第2期118-126,共9页
The national independent innovation demonstration zone(NIIDZ)is an independent innovation policy that plays a crucial role in implementing strategies.Given the importance of the NIIDZ,this study uses panel data of 278... The national independent innovation demonstration zone(NIIDZ)is an independent innovation policy that plays a crucial role in implementing strategies.Given the importance of the NIIDZ,this study uses panel data of 278 prefecture-level cities in China from 2006 to 2020 and empirically examines the effect and internal mechanism of the NIIDZ on green economic efficiency(GEE)using the difference-in-difference model(DID).The results show that the NIIDZ effectively enhances the growth of GEE,and the results remain valid through several robustness tests,such as year-by-year propensity score matching.The transmission mechanism suggests that the NIIDZ indirectly drives GEE by accelerating scientific and technological investment,promoting talent concentration,and optimizing the industrial structure.Moreover,heterogeneity analysis reveals that the promotion effect of the NIIDZ on GEE is more prominent in the eastern region and high green development level areas.The study’s findings can serve as a reference for China to further utilize the policy effectiveness of the NIIDZ and accelerate the high-quality development of the green economy in the future. 展开更多
关键词 National innovation independent demonstration Zone(NIIDZ) Green economy efficiency(GEE) Difference-in-difference model(DID)
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Analysis of the Role of Problem-Based Independent Learning Model in Teaching Cerebral Ischemic Stroke First Aid in Emergency Medicine
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作者 Hua Liu 《Journal of Contemporary Educational Research》 2024年第6期16-21,共6页
Objective:To analyze the effect of using a problem-based(PBL)independent learning model in teaching cerebral ischemic stroke(CIS)first aid in emergency medicine.Methods:90 interns in the emergency department of our ho... Objective:To analyze the effect of using a problem-based(PBL)independent learning model in teaching cerebral ischemic stroke(CIS)first aid in emergency medicine.Methods:90 interns in the emergency department of our hospital from May 2022 to May 2023 were selected for the study.They were divided into Group A(45,conventional teaching method)and Group B(45 cases,PBL independent learning model)by randomized numerical table method to compare the effects of the two groups.Results:The teaching effect indicators and student satisfaction scores in Group B were higher than those in Group A(P<0.05).Conclusion:The use of the PBL independent learning model in the teaching of CIS first aid can significantly improve the teaching effect and student satisfaction. 展开更多
关键词 Problem-based independent learning model Emergency medicine Ischemic stroke First aid teaching SATISFACTION
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The Use of Field Dependence/Independence in Language Acquisition
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作者 操龙升 《海外英语》 2012年第20期114-115,共2页
Field dependence/independence in Language Acquisition are discussed by many language learners.In this article,we will mainly focus on talking about the cognitive style,including the concept of Field-dependence/indepen... Field dependence/independence in Language Acquisition are discussed by many language learners.In this article,we will mainly focus on talking about the cognitive style,including the concept of Field-dependence/independence,their character istics and differences and functions in language acquisition. 展开更多
关键词 FIELD dependence/independence LANGUAGE ACQUISITION
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NONNULL DISTRIBUTION OF THE LIKELIHOOD RATIO CRITERION FOR TESTING THE EQUALITY OF DIAGONAL BLOCKS WITH BLOCKWISE INDEPENDENCE 被引量:5
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作者 A. K. Gupta C. C. Chao(Bowling Green State University Bowling Green, OH 43403-0221 C. C. ChaoJacksonville State Univesity Jacksonville, AL 36265) 《Acta Mathematica Scientia》 SCIE CSCD 1994年第2期195-203,共9页
In this paper, the nonnull moments and the distributions of the likelihood ratio criterion for testing the equality of diagonal blocks with blockwise independence under certain alternatives have derived.
关键词 RATIO BLOCKWISE CRITERION DIAGONAL DISTRIBUTION EQUALITY FOR independence LIKELIHOOD NONNULL
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CONSISTENCY BETWEEN INDEPENDENCE THEOREMS AND GENERALIZED SELF-CONSISTENT METHOD 被引量:1
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作者 杜丹旭 郑泉水 高蕴昕 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1997年第4期355-365,共11页
Recently Zheng & Hwang established a series of independence theorems concerning with planar effective elastic properties. It is manifested that the estimation of the effective elastic properties of microcracked so... Recently Zheng & Hwang established a series of independence theorems concerning with planar effective elastic properties. It is manifested that the estimation of the effective elastic properties of microcracked solids through the generalized self-consistent method (GSCM) contradicts with these independence theorems. In this paper it is shown that such contradiction is actually caused by the approximate algorithm adopted, while the exact solution of GSCM is consistent with these rigorously established independence theorems. Since only an approximate algorithm in GCSM is available in dealing with problems involving non-circular inclusions or holes, an intrinsic GSCM is proposed, which can be performed based on an approximate algorithm and the corresponding estimations are consistent with the independence theorems. 展开更多
关键词 intrinsic Generalised Self-Consistent Method independence energy equivalence effective properties
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On the connotation, challenge and significance of China’s “energy independence” strategy 被引量:6
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作者 ZOU Caineng PAN Songqi ZHAO Qun 《Petroleum Exploration and Development》 2020年第2期449-462,共14页
The world’s energy is in the "third major transformation period" from fossil energy to new energy, and all countries in the world have formulated energy development strategies. Through advanced deployment, ... The world’s energy is in the "third major transformation period" from fossil energy to new energy, and all countries in the world have formulated energy development strategies. Through advanced deployment, the United States is about to achieve "energy independence" relying on "unconventional oil and gas revolution". China’s energy development is faced with four challenges:(1) The population base and economic development scale determine the "totally huge amount" of energy consumption;(2) the "coal rich but oil and gas insufficient" resource structure determines the "unclean" energy consuming structure;(3) the increasing dependence on imported oil and gas determines the "unsafe" energy supply;and(4) the unconventional oil and gas endowment makes it impossible to achieve energy independence by copying the American model. From the perspective of the world energy trend and the unique situation of China’s energy, we put forward a "three-step" strategy for China to achieve "energy independence": From 2020 to 2035, "energy supply security" will be addressed by "cleaning coal, stabilizing oil and gas production and vigorously developing new alternative energy";from 2035 to 2050, the vision of "production independence" will be realized by relying on "domestic production and overseas oil and gas mining rights";from 2050 to 2100, "intelligent energy and new energy" will help China realize "energy independence". The two important signs of China’s "energy independence" are that domestic production accounts for more than 90% of the domestic consumption and clean energy production accounts for more than 70%, and energy security realizes "independence and self-control" and "long-term security". The strategic significance of "energy independence" is to ensure national energy security, drive the development of relevant major industries, achieve energy management reform, and implement the environmental protection goal of zero carbon emissions. The "energy independence" of China is a strategic mission, it might be fulfilled in the future with the growth of the state’s power, even when the domestic energy production does not catch up with the domestic consumption. Perhaps the world’s new technological revolution will exceed expectations, and China’s "energy independence" dream will eventually come true. 展开更多
关键词 energy independence energy revolution intelligent energy COAL unconventional oil and gas new energy energy long march
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A View on Independence of Grammar——Extracts from Syntactic Structures
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作者 马昱 《英语广场(学术研究)》 2012年第6期37-38,共2页
According to Chomsky,the grammar of Language is a device that generates all of the grammatical sequences of Language and none of the ungrammatical ones.However,as the foundation of Universal Grammar,independence of gr... According to Chomsky,the grammar of Language is a device that generates all of the grammatical sequences of Language and none of the ungrammatical ones.However,as the foundation of Universal Grammar,independence of grammar is strongly criticized by many other linguists.This paper aims at reviewing the literature and illustrating different ideas towards Universal Grammar. 展开更多
关键词 Universal Grammar independence of grammar CHOMSKY
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The Criterion of weighting the independence of non-executive directors
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作者 师怡 《商情》 2008年第7期47-,54,共2页
Non-executive directors are now very well established in Chinese business. The uniform and final criterion of weighting the independence of non-executive directors is not available. It will be valuable to draw an anal... Non-executive directors are now very well established in Chinese business. The uniform and final criterion of weighting the independence of non-executive directors is not available. It will be valuable to draw an analogy with the criterion of weighting the independence of non-executive directors in the UK, where over a dozen different criterions are applied. 展开更多
关键词 non-executive directors the independence of non-executive directors CRITERION of weighting the independence
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Sub-independence-spaces 被引量:2
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作者 MAO Huat WANG Gang 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第2期293-299,共7页
聪明地使用独立空格和 B-matroids 的关系,这份报纸第一处理一个独立空格的闭合操作员的性质,由介绍定义并且在电路的帮助下解决一些相对性质一个独立空格的亚独立空格列在后面。
关键词 电路 sub-independence-space 独立空间 闭合操作员
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LINEAR INDEPENDENCE OF THE INTEGER TRANS-LATES OF COMPACTLY SUPPORTED DISTRIBU-TIONS AND REFINABLE VECTORS
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作者 Sun QiyuDept. of Math.,National University of Singapore,10 Kent Ridge Crescent,Singapore 119260,Singapore. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第4期381-396,共16页
In this paper,the global and local linear independence of any compactly supported distributions by using time domain spaces,and of refinable vectors by invariant linear spaces are investigated.
关键词 Global linear independence local linear independence refinable vector invariant space.
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The Researches on Path Independence Problem
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作者 Luo Yunfeng Xiao Renbin & Zhu Mingfu(Institute of Systems Engineering, Huazhong University of Science and Technology,Wuhan 430074, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第2期19-22,共4页
Rationality condition is imposed in Arrow's General Possibility Theorem in order for social choice to be independent of the path of choice. In this Paper, emphasis is laid on the analysis of the relevance of path ... Rationality condition is imposed in Arrow's General Possibility Theorem in order for social choice to be independent of the path of choice. In this Paper, emphasis is laid on the analysis of the relevance of path independence and rationality condition. Two kinds of Path independence, i.e., Plott's path independence and Bandyopadhyay's sequential path independence, are shown, and their meanings with respect to the problem are investigated. 展开更多
关键词 Social choice Rationality condition Path independence Sequential path independence
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Independence Numbers in Trees
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作者 Min-Jen Jou Jenq-Jong Lin 《Open Journal of Discrete Mathematics》 2015年第3期27-31,共5页
The independence number of a graph G is the maximum cardinality among all independent sets of G. For any tree T of order n ≥ 2, it is easy to see that . In addition, if there are duplicated leaves in a tree, then the... The independence number of a graph G is the maximum cardinality among all independent sets of G. For any tree T of order n ≥ 2, it is easy to see that . In addition, if there are duplicated leaves in a tree, then these duplicated leaves are all lying in every maximum independent set. In this paper, we will show that if T is a tree of order n ≥ 4 without duplicated leaves, then . Moreover, we constructively characterize the extremal trees T of order n ≥ 4, which are without duplicated leaves, achieving these upper bounds. 展开更多
关键词 independENT SET independence NUMBER TREE
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Changes and Trends in the Independence of the US Federal Reserve Following the Financial Crisis
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作者 Ma Xue 《Contemporary International Relations》 2019年第5期74-94,共21页
In 2018, US President Donald Trump repeatedly and publicly criticized the US Federal Reserve for raising interest rates too quickly, breaking the long-established precedent for presidents to refrain from intervening i... In 2018, US President Donald Trump repeatedly and publicly criticized the US Federal Reserve for raising interest rates too quickly, breaking the long-established precedent for presidents to refrain from intervening in monetary policy and putting the independence of the Federal Reserve into question. However, this is only the latest development of a longer process: since the financial crisis, the Federal Reserve has been gradually losing its independence, in a quiet and perhaps permanent way. There are several reasons for this trend: the Federal Reserve’s performance during the financial crisis undermined its credibility, the consolidation of political factors arranged against its independence, and the consequences of the financial crisis weakened the economic foundation for its independence. Trump’s rise to power has only strengthened these factors, bringing an additional loss of independence, which will have a profound impact on the economy, society, and politics. 展开更多
关键词 financial CRISIS FEDERAL RESERVE independence Trump administration
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An Analysis of Judy’s Personality of Independence in Daddy-Long-Legs
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作者 郭雅君 《神州》 2016年第11期3-4,共2页
Daddy- Long- Legs written by Jane Webster in 1912 has been always well received since it was published. In the novel, Miss Webster portrays a female image Judy who remained positive although she grew up in asylum and ... Daddy- Long- Legs written by Jane Webster in 1912 has been always well received since it was published. In the novel, Miss Webster portrays a female image Judy who remained positive although she grew up in asylum and bore the brunt of distressing time. She tried her best to improve her ideas and personality and become a writer and paid back to Daddy- Long-Legs.As a result, she got real love from Daddy- Long-Legs and she also became a typical representative of independent females. The author of the paper aims making more teenagers take Judy as an example and learn from her. What’s more, we can gradually develop our own independent spirit. 展开更多
关键词 Judy independence growth CHARACTER ANALYSIS
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Study on Rank Reversal and Independence of Irrelevant Alternatives
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《Journal of Modern Transportation》 1997年第2期64-70,共7页
Rank reversals appearing in AHP are discussed. It is proved with examples that they are in certain degree universal in the process of decision making. The mechanism of rank reversal is expounded. It is believed that... Rank reversals appearing in AHP are discussed. It is proved with examples that they are in certain degree universal in the process of decision making. The mechanism of rank reversal is expounded. It is believed that rank reversal can not deny the reasonableness of AHP and the axioms of independences of irrelevant alternatives. 展开更多
关键词 rank reversal independence of irrelevant alternatives decision making AHP
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Testing conditional independence with data missing at random
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作者 LIU Yi LIU Xiao-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第3期298-312,共15页
It is known that conditional independence is a quite basic assumption in many fields of statistics. How to test its validity is of great importance and has been extensively studied by the literature. Nevertheless, all... It is known that conditional independence is a quite basic assumption in many fields of statistics. How to test its validity is of great importance and has been extensively studied by the literature. Nevertheless, all of the existing methods focus on the case that data are fully observed, but none of them seems having taken into account of the scenario when missing data are present. Motivated by this, this paper develops two testing statistics to handle such a situation relying on the idea of inverse probability weighted and augmented inverse probability weighted techniques. The asymptotic distributions of the proposed statistics are also derived under the null hypothesis. The simulation studies indicate that both testing statistics perform well in terms of size and power. 展开更多
关键词 conditional independence cumulative sum process of residuals missing at random inverse probability weighting re-sampling
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The Influence of the Empowerment of the Elderly Group on Independence of Activities Daily Living in Arjuna Village Bandung
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作者 Ai Rokhayati Ahmad Husni Lia Melianingsih 《Open Journal of Nursing》 2019年第8期925-934,共10页
The increasing number of the elderly in Indonesia as a result of the success of development has led to increasing problems in the elderly group whose natural life journey will experience an old age with all its limita... The increasing number of the elderly in Indonesia as a result of the success of development has led to increasing problems in the elderly group whose natural life journey will experience an old age with all its limitations, especially in the health problems of the elderly who suffer from disabilities compared to younger people. The situation is also added that the elderly usually suffer from a variety of physiological disorders that are chronic, and biological aspect, psychological aspect, socio economic aspect will experience setback. The empowerment of elderly group is an effort to give power or strength so that elderly have independence, especially in aspects of intellectual ability, and aspects Physical, the empowerment of the elderly is done by improving ability through education. This study aims to analyze the influence of empowerment of the elderly group through health education on the independence of Activitiey Daily Living (ADL). The research design used quasi-experiment with the approach of pre post test group design without comparison (control), while the data analysis used t-test. The results of the study before being carried out empowerment through health education on the independence of the average value of independence were 9.9506 (SD 4.66074) and the result after being carried out empowerment through health education became 13.2716 (SD.4.61523) Research Results showed statistically significant influence on empowering the elderly group through health education to independence of the ADL with a p-value of 0.04. Based on this, it is recommended that empowerment for the elderly should be determined in Posbindu activities. The effect of empowering the elderly group through more effective health education can influence the level of independence by providing a guidebook (module) which is equipped with interesting pictures about the procedures for fulfilling the needs of daily activities, finished providing educational guidebooks. The guidebook is given to the elderly group can be read repeatedly so that it affects the elderly memory in a longer period of time. 展开更多
关键词 EMPOWERMENT Elderly Groups independence ACTIVITIES DAILY LIVING
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