• Title/Summary/Keyword: 공통척도

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Inducing Irrational Numbers in Junior High School (중학교에서의 무리수 지도에 관하여)

  • Kim, Boo-Yoon;Chung, Young-Woo
    • Journal for History of Mathematics
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    • v.21 no.1
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    • pp.139-156
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    • 2008
  • We investigate the inducing method of irrational numbers in junior high school, under algebraic as well as geometric point of view. Also we study the treatment of irrational numbers in the 7th national curriculum. In fact, we discover that i) incommensurability as essential factor of concept of irrational numbers is not treated, and ii) the concept of irrational numbers is not smoothly interconnected to that of rational numbers. In order to understand relationally the incommensurability, we suggest the method for inducing irrational numbers using construction in junior high school.

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An Approach to Improve the Credibility of Similarity Calculation in CF-based Recommender Systems (협업필터링 기반 추천시스템에서 유사도 계산의 신뢰성 향상 방안)

  • Lee, Gun Woo;Jeon, Dong Yeoup;Ha, Jiwoon;Kim, Hyung-ook;Kim, Sang-Wook
    • Proceedings of the Korea Information Processing Society Conference
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    • 2015.10a
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    • pp.1144-1145
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    • 2015
  • 협업 필터링 기반 추천 시스템에서는 이웃 사용자를 정확하게 찾는 것이 추천 정확도에 핵심적인 영향을 미친다. 그러나 기존의 유사도 척도는 사용자가 공통으로 평가한 아이템만을 고려하여 유사도를 계산하기 때문에 이러한 아이템이 적은 사용자 간의 유사도가 부정확하게 계산되는 문제가 있다. 본 논문에서는 이러한 문제를 극복하기 위해 공통으로 평가하지 않은 아이템을 함께 고려하여 유사도를 계산하는 방안을 제안한다. 또한, 실험을 통해 제안하는 방안이 협업 필터링 기반 추천 시스템의 정확도 향상에 기여함을 보인다.

A New Similarity Measure based on Separation of Common Ratings for Collaborative Filtering

  • Lee, Soojung
    • Journal of the Korea Society of Computer and Information
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    • v.26 no.11
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    • pp.149-156
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    • 2021
  • Among various implementation techniques of recommender systems, collaborative filtering selects nearest neighbors with high similarity based on past rating history, recommends products preferred by them, and has been successfully utilized by many commercial sites. Accurate estimation of similarity is an important factor that determines performance of the system. Various similarity measures have been developed, which are mostly based on integrating traditional similarity measures and several indices already developed. This study suggests a similarity measure of a novel approach. It separates the common rating area between two users by the magnitude of ratings, estimates similarity for each subarea, and integrates them with weights. This enables identifying similar subareas and reflecting it onto a final similarity value. Performance evaluation using two open datasets is conducted, resulting in that the proposed outperforms the previous one in terms of prediction accuracy, rank accuracy, and mean average precision especially with the dense dataset. The proposed similarity measure is expected to be utilized in various commercial systems for recommending products more suited to user preference.

Satellite Battery Cell Voltage Monitor System Using a Conventional Differential Amplifier (종래의 차동증폭기를 사용한 인공위성 배터리 셀 전압 감시 시스템)

  • Koo, Ja-Chun;Choi, Jae-Dong;Choi, Seong-Bong
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.33 no.2
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    • pp.113-118
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    • 2005
  • This paper shows a satellite battery cell voltage monitor system to make differential voltage measurements when one or both measurement points are beyond voltage range allowed by a conventional differential amplifier. This system is particularly useful for monitoring the individual cell voltage of series-connected cells that constitute a rechargeable satellite battery in which some cell voltages must be measured in the presence of high common mode voltage.

The Difference of Cognitive Function in Posttraumatic Stress Disorder after Traffic Accident According to Severity of Symptom (교통사고로 인한 외상 후 스트레스 장애에서 증상 정도에 따른 인지기능의 차이)

  • Lee, Jae-Young;Kee, Baik-Seok;Jo, Sun-Dong;Suh, Dong-Soo
    • Korean Journal of Psychosomatic Medicine
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    • v.11 no.1
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    • pp.36-43
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    • 2003
  • Objectives: The purpose of this study was to evaluate the difference of cognitve function among patients with posttraumatic stress disorder according to severity of symptoms. Methods: The subjects were 90 psychiatric inpatients and outpatients with posttraumatic stress disorer(by DSM-IV criteria) after traffic accident. The severity of symptoms was assessed by MMPI subscales; depression, psychasthenia, schizophrenia. The impairment of cognitive function was assessed by Korean Wechsler Intelligence Scale(K-WAIS). Based on scores of the MMPI subscales, the patients were divided into high group(above 70 percentile) and low group(below 30 percentile). We estimated the difference of the K-WAIS score and subtest score in the low group and high group of the MMPI subscales by indedpendent t-test. Results: The scores of high group is significantly higher in the subtests of information, vocabulary, similarity, picture completion, and picture arrangement than the low group for psychasthenia subscale of MMPI. And the score of high group is significantly higher in full scale I.Q., verbal I.Q., performance I.Q., verbal subscales except digit span and simiarity, and performance subscales than low group for schiozphrenia subscale of MMPI. Conclusion: It was found cognitive function was more impaired in the group of PTSD with severe symptom compared to the group of PTSD with mild symptoms. We suggest that psychiatrist should consider various cognitive approaches as well as pharmacotherapy in the management of PTSD.

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Male Gender Role and Adjustment of Korean Men (남성 성역할이 우리나라 남성들의 적응에 미치는 영향)

  • Suae Park;Eunkyung Jo
    • Korean Journal of Culture and Social Issue
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    • v.8 no.2
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    • pp.77-103
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    • 2002
  • The goal of this study was to examine the effects of male gender role on the adjustment of Korean men. In study 1 Korean Male gender Role Scale was developed. A 52-item scale was constructed based on the responses of 432 college-aged and middle-aged men to theoretically-derived preliminary items. Five factors were extracted: achievement orientation, the initiative, task orientation, responsibility for family and friendship with male friends. Study 2 examined the relationship between male gender role and several adjustment variables. Correlational analyses indicated that in the college men self-esteem and career identity were positively correlated with the initiative and friendship with male friends was positively correlated with life satisfaction. College men's depression level was negatively correlated with the initiative and task orientation. Among the middle-aged men, self-esteem was also positively correlated with the initiative and task orientation. But responsibility for family was positively correlated with depression and job dissatisfaction in the middle-aged men. In both groups satisfaction with male gender role was positively correlated with self-esteem and life satisfaction but negatively correlated with depression. Finally, limitations of this study and direction of future research were discussed.

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Validity Verification of a Korean Version of Recovery Scale(Client Assessment Summary) for Alcoholics (알코올중독자의 회복척도 CAS(Client Assessment Summary) 한국어판의 타당도 검증)

  • Rhee, Young-Sun;Kim, Soo-Youn
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.11
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    • pp.386-394
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    • 2016
  • This study investigates the validity of a Korean version of the Client Assessment Summary (CAS), which is a tool used to assess the recovery of alcoholics. We investigated the Korean CAS's suitability for use in assessing the scale of recovery scale of general alcoholics in Korea. In this study, we analyzed the data of 205 abstaining alcoholics in order to determine the validity of the Korean CAS. We undertook relationship analyses of CAS contents, reliability, and composition validity through factor analysis. In addition, we assessed ARS, abstinence period, abstinence self-efficacy, illness insight, and motivation change variables. The factor analysis results, performed after verification of content suitability by assessing 12 questions and 4 factors, confirmed the tool's composition validity, with the results showing relatively high values (R2 = 76.26%, communality ${\geq}0.6$, and KMO = 0.92). Moreover, internal consistency was acceptable (Cronbach's alpha = 0.92), and the correlations among ARS, abstinence self-efficacy, illness insight, and motivation change variables confirmed the validity of the Korean CAS. The proposed Korean CAS is expected to be useful when academically and clinically assessing the recovery of alcoholics; thereby, eventually contributing to successful recoveries from alcoholism.

Internalization and Externalization Factor Structure of PAI-A Revised (PAI-A 증보판의 내재화 및 외현화 요인구조)

  • Park, Eun-Young;Park, Eun-Young;Hong, Sang-Hwang
    • Korean Journal of School Psychology
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    • v.16 no.3
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    • pp.315-337
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    • 2019
  • This study was intended to verify that the Revised PAI-A scale reflected the internalization and externalization classification of adolescence problem behavior. For this purpose, exploratory factor analysis and confirmatory factor analysis were conducted using PAI-A restandardization data. In addition, 31 Revised PAI-A sub-scales and SUI scale were used to identify the detailed factor structures. As a result of the analysis, the classification of internalization and externalization factors was similar to that of previous studies. In detail, the sub-scales of ANX·DEP and SUI were classified into internalization, the sub-scales of ANT and AGG were classified into externalization. It is noteworthy that each sub-scale of PAI-A was separated into internalization or externalization. For example, BOR-A, BOR-I, and BOR-N were loaded into internalization, but BOR-S into externalization. Next, in order to confirm whether the structure of the derived internalization and externalization factors can be applied to new samples, 350 samples were randomly extracted and confirmatory factor analysis was conducted, but exclusive of the samples used for exploratory factor analysis. As a result of confirmatory factor analysis, the appropriate indices of internalization and externalization classification was close to the good level. Therefore, the Revised PAI-A scales have theoretical relevance to internalization and externalization classification of problem behaviors. Based on the results of this study, it is expected that it can be used helpfully in the school settings in the future. Finally, the significance and limitations of this study were discussed.

Design for Wastewater Neutralization Network in Yeosu Petrochemical Complex by Multi-Criteria Decision Making Strategy (다중척도 의사결정 전략을 이용한 여수 석유화학단지의 폐수 중화망 설계)

  • Lee, Tai-Yong
    • Clean Technology
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    • v.17 no.2
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    • pp.175-180
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    • 2011
  • A novel multi-criteria decision making strategy is developed for the construction of industrial symbiosis network in eco-industrial park and the strategy is applied to the construction of acid/alkali wastewater neutralization network in Yeosu industrial complex. Acid (or alkali) wastewater is commonly generated in chemical industries, and it can be used as neutralizing agent for alkali (or acid) wastewater generated from another source. As a consequence, a large-scale industrial symbiosis network for wastewater neutralization can be constructed in petrochemical complexes where a large amount of acid/alkali wastewater is generated. In this study, substance flow model is constructed which describes the wastewater neutralization network and multi-criteria decision making strategy is applied to find a few candidate for industrial symbiosis network.

Creation and clustering of proximity data for text data analysis (텍스트 데이터 분석을 위한 근접성 데이터의 생성과 군집화)

  • Jung, Min-Ji;Shin, Sang Min;Choi, Yong-Seok
    • The Korean Journal of Applied Statistics
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    • v.32 no.3
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    • pp.451-462
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    • 2019
  • Document-term frequency matrix is a type of data used in text mining. This matrix is often based on various documents provided by the objects to be analyzed. When analyzing objects using this matrix, researchers generally select only terms that are common in documents belonging to one object as keywords. Keywords are used to analyze the object. However, this method misses the unique information of the individual document as well as causes a problem of removing potential keywords that occur frequently in a specific document. In this study, we define data that can overcome this problem as proximity data. We introduce twelve methods that generate proximity data and cluster the objects through two clustering methods of multidimensional scaling and k-means cluster analysis. Finally, we choose the best method to be optimized for clustering the object.