• Title/Summary/Keyword: multidimensional index

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k-Nearest Neighbor Querv Processing using Approximate Indexing in Road Network Databases (도로 네트워크 데이타베이스에서 근사 색인을 이용한 k-최근접 질의 처리)

  • Lee, Sang-Chul;Kim, Sang-Wook
    • Journal of KIISE:Databases
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    • v.35 no.5
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    • pp.447-458
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    • 2008
  • In this paper, we address an efficient processing scheme for k-nearest neighbor queries to retrieve k static objects in road network databases. Existing methods cannot expect a query processing speed-up by index structures in road network databases, since it is impossible to build an index by the network distance, which cannot meet the triangular inequality requirement, essential for index creation, but only possible in a totally ordered set. Thus, these previous methods suffer from a serious performance degradation in query processing. Another method using pre-computed network distances also suffers from a serious storage overhead to maintain a huge amount of pre-computed network distances. To solve these performance and storage problems at the same time, this paper proposes a novel approach that creates an index for moving objects by approximating their network distances and efficiently processes k-nearest neighbor queries by means of the approximate index. For this approach, we proposed a systematic way of mapping each moving object on a road network into the corresponding absolute position in the m-dimensional space. To meet the triangular inequality this paper proposes a new notion of average network distance, and uses FastMap to map moving objects to their corresponding points in the m-dimensional space. After then, we present an approximate indexing algorithm to build an R*-tree, a multidimensional index, on the m-dimensional points of moving objects. The proposed scheme presents a query processing algorithm capable of efficiently evaluating k-nearest neighbor queries by finding k-nearest points (i.e., k-nearest moving objects) from the m-dimensional index. Finally, a variety of extensive experiments verifies the performance enhancement of the proposed approach by performing especially for the real-life road network databases.

Symptom Checklist-90-Revision(SCL-90-R) in Inpatients on Tension headache and Insomnia (긴장성 두통 및 불면을 주소로 입원한 환자의 간이정신진단검사(SCL-90-R)의 진단별 특성)

  • Shim, Sang-Min;Koo, Byung-Soo;Kim, Kyeong-Ok
    • Journal of Oriental Neuropsychiatry
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    • v.14 no.1
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    • pp.117-131
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    • 2003
  • SCL-90-R is a multidimensional self-report symptom inventory devoloped by Derogatis and his coworkers. Since it was standardized into Korean version in 1978 by Won and Kim et aI., but it has been rarely studies for the clinical groups. Objectives : This study sought to define a diagnotic character of SCL-90-R of tension headache and insomnia inpatients groups. Methods : We determined a diagnotic character of 17 tension headache and 23 insomnia patients by means of SCL-90-R, and compared with normal groups in order to characterize subscale of SCL-90-R in patients with tension headache and insomnia from Neurasthenia. Results : 1. Male tension headache group has significant difference in Somatization and Depression subscales, female group in Somatization, Obsessive-Compulsive, Depression and Hostility subscales. 2. Female insomnia group has significant difference in Anxiety subscale. Although there are a little significiant, many subscales such as Somatization, Obsessive-Compulsive, Depression and Hostility are higher than normal group. 3. There are significant difference in GSI and PDSI of Global index, which means that we use that for objective index of tension headache and insomnia from Neurasthenia. Conclusions : All of these results show that SCL-90-R is useful inventory to characterize and screening for Neurasthenia.

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Bulk Insertion Method for R-tree using Seeded Clustering (R-tree에서 Seeded 클러스터링을 이용한 다량 삽입)

  • 이태원;문봉기;이석호
    • Journal of KIISE:Databases
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    • v.31 no.1
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    • pp.30-38
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    • 2004
  • In many scientific and commercial applications such as Earth Observation System (EOSDIS) and mobile Phone services tracking a large number of clients, it is a daunting task to archive and index ever increasing volume of complex data that are continuously added to databases. To efficiently manage multidimensional data in scientific and data warehousing environments, R-tree based index structures have been widely used. In this paper, we propose a scalable technique called seeded clustering that allows us to maintain R-tree indexes by bulk insertion while keeping pace with high data arrival rates. Our approach uses a seed tree, which is copied from the top k levels of a target R-tree, to classify input data objects into clusters. We then build an R-tree for each of the clusters and insert the input R-trees into the target R-tree in bulk one at a time. We present detailed algorithms for the seeded clustering and bulk insertion as well as the results from our extensive experimental study. The experimental results show that the bulk insertion by seeded clustering outperforms the previously known methods in terms of insertion cost and the quality of target R-trees measured by their query performance.

Connection Strategies between Port and City functions - Focused on the case of Incheon - (항만과 도시기능의 연계 방안에 관한 연구 - 인천의 사례를 중심으로 -)

  • Lee, Tae-Hwee;Yeo, Gi-Tae
    • Journal of Navigation and Port Research
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    • v.36 no.1
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    • pp.75-80
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    • 2012
  • The aim of this paper is to draw out the connection strategies between port and city functions. The case study was made on the port city of Incheon using Multidimensional Statistics(MDS) which groups 18 port cities targeted into two or more categories. The used factors inserted into the methodology were container cargo volumes, population, area of the city, number of liner calling, Relative Concentration Index(RCI). As results, Yokohama was identified as the best port city which can possibly give the meaningful guideline to Incheon port. The port-city is superior to that of Incheon in the area of port hinterland and varieties of business models. The port-city also has consistent policies on improvement of port and city functions.

Reliability and Validity of Turkish Version of the Caregiver Quality of Life Index Cancer Scale

  • Yakar, Hatice Karabuga;Pinar, Rukiye
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.7
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    • pp.4415-4419
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    • 2013
  • Background: Measuring effects of cancer on family caregivers is important to develop methods which can improve their quality of life (QOL). Nevertheless, up to now, only a few tools have been developed to be used in this group. Among those, the Caregiver Quality of Life Index-Cancer Scale (CQOLC) has met minimum psychometric criteria in different populations in spite of conflicting results. The present study was conducted to evaluate reliability and validity of CQOLC among Turkish cancer family caregivers. Materials and Methods: The CQOLC was administered to 120 caregivers, along with Beck Depression Inventory (BDI), Medical Outcomes Study MOS 36- Item Short Form Health Survey (SF-36), State-Trait Anxiety Inventory (STAI), and Multidimensional Scale of Perceived Social Support (MSPSS). Internal consistency and test-retest stability were used to investigate reliability. Construct validity was examined by using known group method, convergent, and divergent validity. For the known group method, we hypothesized that CQOLC scores would differ between depressed and non-depressed subjects. We investigated convergent validity by correlating scores for CQOLC with scores for other similar measures including SF-36 and STAI. The MSPSS was completed at the same time as CQOLC to provide divergent validity. Results: The values for internal consistency and test-retest correlation were 0.88 and 0.96, respectively. The CQOLC discriminated those who were depressed from those who were not. Convergent validity supported strong correlations between CQOLC scores and two main component scores (PCS, MCS) in SF-36 although there was a weak correlation between CQOLC and STAI scores. Regarding divergent validity, the correlation between CQOLC and MSPSS was in the low range, as expected. Conclusions: The Turkish CQOLC is a reliable and valid tool and it can be utilized to determine QOL of family caregivers.

Correlation between Fatigue and Quality of Life Caused by Stress of Researchers' Work (연구직의 직무 스트레스 요인에 따른 피로, 삶의 질의 관계)

  • Park, Hye Joo;Kim, Yun Young;Park, Ki Hyun;Lee, Si Woo;Yoo, Jong-Hyang
    • Korean Journal of Occupational Health Nursing
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    • v.23 no.3
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    • pp.171-179
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    • 2014
  • Purpose: The purpose of this research was to provide baseline data by utilizing solutions to health problems caused by work-related stress and to examine a way of treatment by comparing and analyzing how the stresses link to fatigue and quality of researchers' life. Methods: A survey was conducted with 50 researchers working for in H research institute in Daejeon Metropolitan City from April 10th to May 10th, 2012 to examine the correlation of work stress, fatigue and quality of life. The data were analyzed using the Kruskal-Wallis test to look into examine the difference in work stress, fatigue, and quality of life. Also, the correlation of work stress, fatigue and quality of life was measured through by the Pearson correlation coefficient. The data collected through the questionnaires was were analyzed by SPSS 21.0 based on the significant level with a p-value, 0.05. Results: The results showed that fatigue was caused by work stresses in researchers and quality of life was ranked in a relatively low level. Correlation of work stresses, quality of life and fatigue and work stresses against mental health index was negative and fatigue against physical index was also negative. Conclusion: It is necessary to maintain more detailed provisions in order to improve mental health and stress level of researchers. Moreover, systematic, in-depth evaluation should be done to reduce researcher's work-related stress and fatigue. In addition, stress management and prevention program should be implemented for these researchers.

Hybrid Lower-Dimensional Transformation for Similar Sequence Matching (유사 시퀀스 매칭을 위한 하이브리드 저차원 변환)

  • Moon, Yang-Sae;Kim, Jin-Ho
    • The KIPS Transactions:PartD
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    • v.15D no.1
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    • pp.31-40
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    • 2008
  • We generally use lower-dimensional transformations to convert high-dimensional sequences into low-dimensional points in similar sequence matching. These traditional transformations, however, show different characteristics in indexing performance by the type of time-series data. It means that the selection of lower-dimensional transformations makes a significant influence on the indexing performance in similar sequence matching. To solve this problem, in this paper we propose a hybrid approach that integrates multiple transformations and uses them in a single multidimensional index. We first propose a new notion of hybrid lower-dimensional transformation that exploits different lower-dimensional transformations for a sequence. We next define the hybrid distance to compute the distance between the transformed sequences. We then formally prove that the hybrid approach performs the similar sequence matching correctly. We also present the index building and the similar sequence matching algorithms that use the hybrid approach. Experimental results for various time-series data sets show that our hybrid approach outperforms the single transformation-based approach. These results indicate that the hybrid approach can be widely used for various time-series data with different characteristics.

Development of multi-dimensional body image scale for malaysian female adolescents

  • Chin, Yit Siew;Taib, Mohd Nasir Mohd;Shariff, Zalilah Mohd;Khor, Geok Lin
    • Nutrition Research and Practice
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    • v.2 no.2
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    • pp.85-92
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    • 2008
  • The present study was conducted to develop a Multi-dimensional Body Image Scale for Malaysian female adolescents. Data were collected among 328 female adolescents from a secondary school in Kuantan district, state of Pahang, Malaysia by using a self-administered questionnaire and anthropometric measurements. The self-administered questionnaire comprised multiple measures of body image, Eating Attitude Test (EAT-26; Gamer & Garfinkel, 1979) and Rosenberg Self-esteem Inventory (Rosenberg, 1965). The 152 items from selected multiple measures of body image were examined through factor analysis and for internal consistency. Correlations between Multi-dimensional Body Image Scale and body mass index (BMI), risk of eating disorders and self-esteem were assessed for construct validity. A seven factor model of a 62-item Multi-dimensional Body Image Scale for Malaysian female adolescents with construct validity and good internal consistency was developed. The scale encompasses 1) preoccupation with thinness and dieting behavior, 2) appearance and body satisfaction, 3) body importance, 4) muscle increasing behavior, 5) extreme dieting behavior, 6) appearance importance, and 7) perception of size and shape dimensions. Besides, a multidimensional body image composite score was proposed to screen negative body image risk in female adolescents. The result found body image was correlated with BMI, risk of eating disorders and self-esteem in female adolescents. In short, the present study supports a multi-dimensional concept for body image and provides a new insight into its multi-dimensionality in Malaysian female adolescents with preliminary validity and reliability of the scale. The Multi-dimensional Body Image Scale can be used to identify female adolescents who are potentially at risk of developing body image disturbance through future intervention programs.

Developing New Journal Citation Indicators including Immediate Citation Frequencies in the Published Year (출판년도의 즉시 인용빈도를 포함하는 학술지 인용지수 개발)

  • Lee, Jae Yun
    • Journal of the Korean Society for Library and Information Science
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    • v.52 no.4
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    • pp.71-90
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    • 2018
  • The importance of citation measures has been increasing in the evaluation of scholarly journals and it becomes a major issue for Korean Citation Index (KCI) journals. The Journal Impact Factor (JIF), a widely used measure for academic journals, has a problematic issue that it does not include the number of citations for a paper immediately made in the year in which the cited paper was published. On the contrary, the Diachronous Impact Factor (IMP) includes the number of citations made in the published year, but IMP is a measure for papers published a few years ago, not in the last year. It does not represent the recent value of journals effectively. To overcome these problems, Total Impact Factor (TIF) and Mean Impact Factor (MIF) are proposed as new journal citation indicators. This study calculated the performance of proposed indicators experimentally on KCI data. The result shows that TIF is a promising measure for the multidimensional evaluation of humanities and social sciences journals in Korea because it has high stability by year and includes the immediate citations of the published year.

The impact of quality of life measured by WHOQOL-BREF on mortality in maintenance hemodialysis patients: a single center retrospective cross-sectional study

  • Seong Gyu Kim;In Hee Lee
    • Journal of Yeungnam Medical Science
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    • v.40 no.1
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    • pp.49-57
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    • 2023
  • Background: Several previous studies have reported that quality of life (QoL) in hemodialysis patients affects mortality. However, the 36-item Short Form Health Survey, which has been used mainly in previous studies, is complicated in terms of questionnaire composition and interpretation. This study aimed to identify the impact of QoL on mortality in hemodialysis patients using an easier and simpler diagnostic tool. Methods: This retrospective study included 160 hemodialysis patients. QoL was evaluated using the World Health Organization Quality of Life Questionnaire-Brief version (WHOQOL-BREF). Psychosocial factors were evaluated using the Hospital Anxiety and Depression Scale, Multidimensional Scale of Perceived Social Support, Montreal Cognitive Assessment, and Pittsburgh Sleep Quality Index. We also evaluated medical factors, such as dialysis adequacy and laboratory results. Results: The mean hemodialysis vintage was 70.7±38.0 months. The proportion of patients who were elderly was higher in the mortality group than in the surviving group, and the Charlson Comorbidity Index score was also higher in the former group. Of the four domains of the WHOQOL-BREF, the physical health and psychological scores of the mortality group were significantly lower than those of the survival group. When the score in the physical health domain or psychological domain was ≤10, the 10-year mortality rate after hemodialysis initiation increased by approximately 2.3- and 2-fold, respectively. Conclusion: QoL may have a significant effect on mortality in patients undergoing hemodialysis. The WHOQOL-BREF is an instrument that can measure QoL relatively easily and can be used to improve the long-term prognosis of patients undergoing hemodialysis.