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Shadow Recovery for Column-based Databases (컬럼-기반 데이터베이스를 위한 그림자 복구)

  • Byun, Si-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.4
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    • pp.2784-2790
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    • 2015
  • The column-oriented database storage is a very advanced model for large-volume data transactions because of its superior I/O performance. Traditional data storages exploit row-oriented storage where the attributes of a record are placed contiguously in hard disk for fast write operations. However, for search-mostly data warehouse systems, column-oriented storage has become a more proper model because of its superior read performance. Recently, solid state drive using flash memory is largely recognized as the preferred storage media for high-speed data analysis systems. In this research, we propose a new transaction recovery scheme for a column-oriented database environment which is based on a flash media file system. We improved traditional shadow paging schemes by reusing old data pages which are supposed to be invalidated in the course of writing a new data page in the flash file system environment. In order to reuse these data pages, we exploit reused shadow list structure in our column-oriented shadow recovery(CoSR) scheme. CoSR scheme minimizes the additional storage overhead for keeping shadow pages and minimizes the I/O performance degradation caused by column data compression of traditional recovery schemes. Based on the results of the performance evaluation, we conclude that CoSR outperforms the traditional schemes by 17%.

소 해면형 뇌증/양 스크래피 -병리학적 감별진단과 진단방법 국제표준-

  • 강영배;진영화;위성환;조남인
    • Journal of the korean veterinary medical association
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    • v.32 no.4
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    • pp.234-246
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    • 1996
  • 양의 스크래피(scrapie)는 우리나라에서의 발생보고가 없는 해외가축전염병의 일종이며, 동물의 전염성 해면형 뇌증(Transmissible Spomgifrom Encephalopathies; TSEs)중 역사가 가장 오랜 질병인데, 현재 영국에서 문제되고 있는 새로운 전염병인 소 해면형 뇌증(Bovine Spongiform Encephalopathy; BSE) 즉 일명 광우병(mad cow disease)과의 어떤 연관 가능성 때문에 수의학계의 관심의 대상이 되고 있는 질병이다. 일단 감염되어 발병되면 치료대책 없이 100$\%$ 폐사되는 세기의 불치병으로 알려진, 소 해면형 뇌증(BSE)은 영국에서 현재 사람의 크로이츠휄트-야콥병(Creutzfeldt-Jakob disease; CJD)과의 관련 가능성 여부를 놓고 독특한 문제가 되고 있는 세계적인 희귀질병이다. 이들 질병에 대하여는 아직까지 확실한 병인체가 밝혀져 있지도 않으며, 그렇기 때문에 면역 혈청학적 진단방법도 확립되어 있지 못할 뿐만아니라 예방백신의 개발 또한 불가능하다. 다만, 임상적인 병력과 임상소견, 뇌조직 표본에 대한 현미경 검사 또는 전자현미경 검사에 의한 특이소견 관찰 등 조직병리학적 진단만이 가능할 뿐이다. 본편에서는 소 해면형 뇌증(BSE)의 병리학적 감별진단과 관련, 지금까지 보고된 임상증상을 검토해보고, 우리나라에서 경험한 소의 광견병에 대한 조직병리학적 진단 재료를 근거로하여 감별진단을 위한 참고자료로 설명하고, 국제수역사무국(Office de International Epizooties; O.I.E.)에서 발생한 Manual of Standards for Diagnostic Tests and Vaccines for List A and B Diseases of Mammals, Birds and Bees(1992)(포유류, 조류, 꿀벌에 있어서의 A급 및 B급 질병에 대한 진단시약 및 예방백신에 대한 표준지침) 중에서 소 해면형 뇌증(B 83; p 742-747)과 스크래피(B 32; p 424-427)에 관한 내용 (Chapter 22, 205-215)을 기본자료로 제공하고자 한다.

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STRATEGIC RESEARCH AT ORNL FOR THE DEVELOPMENT OF ADVANCED COATED CONDUCTORS: PART - I

  • Christen, D.K.;Cantoni, C.;Feenstra, R.;Aytug, T.;Heatherly, L.;Kowalewski, M.M.;List, F.A.;Goyal, A.;Kroeger, D.M.
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.339-339
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    • 2002
  • In the RABiTS approach to coated conductor development, successful (both economic and technological) depends on the refinement and optimization of each of three important components: the metal tape substrate, the buffer layer(s), and the HTS layer. Here we will report on the ORNL approach and progress in each of these areas. - Most applications will require metal tapes with low magnetic hysteresis, mechanical strength, and excellent crystalline texture. Some of these requirements are competing. We report on progress in obtaining a good combination of these characteristics on metal alloys of Ni-Cr and Ni-W. - The deposition of appropriate buffer layers is a crucial step. Recently, base research has shown that the presence of a stable sulfur superstructure present on the metal surface is needed for the nucleation and epitaxial growth of vapor-deposited seed buffer layers such as YSZ, CeO$_2$ and SrTiO$_3$. We report on the details and control of this superstructure for nickel tapes, as well as recent results for Cu and Ni-13%Cr. - Processes for deposition of the HTS coating must economically provide large values of the figure-of-merit for conductors, current x length. At ORNL, we have devoted efforts to a precursor/post-annealing approach to YBCO coatings, for which the deposition and reaction steps are separate. We describe motivation for and progress toward developing this approach. - Finally, we address some issues for the implementation of coated conductors in real applications, including the need for texture control and electrical stabilization of the HTS coating.

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Psychological analysis of dental orthodontic patients using SCL-90-R (간이정신진단검사를 이용한 치과교정환자의 심리분석)

  • Ko, Hyo-Jin;Lee, So-Young;Yu, Byeng-Chul
    • Journal of Korean society of Dental Hygiene
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    • v.12 no.1
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    • pp.37-46
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    • 2012
  • Objectives : This research was investigated to evaluate the psychological characteristics and changes of psychological state among dental orthodontic patients. Methods : This cross-sectional questionnaire research was conducted with 230 dental orthodontic patients in Busan from December 23, 2009 to March 6, 2010. The psychological analysis of dental orthodontic treatment patients was performed with Symptom checklist-90-revision(SCL-90-R) considering 5 general characteristics and 2 treatment period related characteristics. Estimated psychological results were changed T-score. Data analysis was performed with descriptive analysis, t-test and ANOVA using SAS(ver 9.1) program. Results : The levels of T-score of SCL-90-R were $43.88{\pm}7.50$ in hostility(HOS), $43.38{\pm}4.64$ in phobic anxiety(PHOB), $43.20{\pm}6.24$ in somatization(SOM), $42.13{\pm}6.71$ in paranoid ideation(PAR), $41.39{\pm}8.16$ in interpersonal sensitive(I-S), $41.01{\pm}7.90$ in obsessive-compulsive(O-C), $40.96{\pm}5.37$ in psychoticism(PSY), $40.96{\pm}5.19$ in anxiety(ANX) and $39.81{\pm}6.80$ in depression(DEP), respectively. The T-score of phobic anxiety in before treatment group was higher than that of treatment groups. The T-score of interpersonal sensitive and paranoid ideation in over 36 months treatment period group were higher than that of other treatment period groups. Conclusions : Phobic anxiety(PHOB), interpersonal sensitive(I-S) and paranoid ideation(PAR) were affected in pre-treatment and long-term treatment dental orthodontic patients. Psychological management methods considering treatment period are needed to improve mental health of dental orthodontic patients.

Current Status(1994) of Neonatal Surgery in Korea -Survey among the members of Korean Association of Pediatric Surgeons- (1994년도 한국신생아외과의 현황 - 대한소아외과학회 회원대상 전국조사 -)

  • Kim, W.K.;Kim, S.Y.;Kim, S.K.;Kim, I.K.;Kim, J.C.;Park, K.W.;Park, Y.S.;Park, W.H.;Park, J.S.;Song, Y.T.;Oh, S.M.;Lee, D.S.;Lee, M.D.;Lee, S.C.;Chang, S.I.;Chung, E.S.;Jung, P.M.;Joo, J.S.;Choi, S.O.;Huh, Y.S.;Hwang, E.H.
    • Advances in pediatric surgery
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    • v.2 no.1
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    • pp.26-32
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    • 1996
  • To understand the current status of neonatal surgery in Korea, a survey was made among the 27 members of Korean Association of Pediatric Surgeons. Response rate among surgeons was 78 percent, eighteen hospitals participated in this study. Five hundred and three cases of neonatal surgical patients were analyzed. In Korea, about 50% of cases were treated at the hospital in the capital city area. Regional number of patients were closely related to the regional population. Imperforate anus(19%), atresia/stenosis of gut(12%), and Hirschsprung's diseases(12%) were sitting at the top in the list. Majority of operation was done within the first week of life, especially during the first 24 hour period. Eighty per cent was major or so called index cases. Mortality in so-called index cases was 17%. High mortality was observed in patients with diaphragmatic hernia(47%), gastrointestinal perforation(65%) and esophageal atresia(28%). Low birth weight babies showed higher mortality in gastrointestinal perforation, esophageal atresia and abdominal wall defect. These were compared to 1993 survey of Japanese Society of Pediatric Surgeons.

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An Indexing Technique for Object-Oriented Geographical Databases (객체지향 지리정보 데이터베이스를 위한 색인기법)

  • Bu, Ki-Dong
    • Journal of the Korean association of regional geographers
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    • v.3 no.2
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    • pp.105-120
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    • 1997
  • One of the most important issues of object-oriented geographical database system is to develop an indexing technique which enables more efficient I/O processing within aggregation hierarchy or inheritance hierarchy. Up to present, several indexing schemes have been developed for this purpose. However, they have separately focused on aggregation hierarchy or inheritance hierarchy of object-oriented data model. A recent research is proposing a nested-inherited index which combines these two hierarchies simultaneously. However, this new index has some weak points. It has high storage costs related to its use of auxiliary index. Also, it cannot clearly represent the inheritance relationship among classes within its index structure. To solve these problems, this thesis proposes a pointer-chain index. Using pointer chain directory, this index composes a hierarchy-typed chain to show the hierarchical relationship among classes within inheritance hierarchy. By doing these, it could fetch the OID list of objects to be retrieved more easily than before. In addition, the pointer chain directory structure could accurately recognize target cases and subclasses and deal with "select-all" typed query without collection of schema semantic information. Also, it could avoid the redundant data storing, which usually happens in the process of using auxiliary index. This study evaluates the performance of pointer chain indexing technique by way of simulation method to compare nested-inherited index. According to this simulation, the pointer chain index is proved to be more efficient with regard to storage cost than nested-inherited index. Especially in terms of retrieval operation, it shows efficient performance to that of nested-inherited index.

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Index Cases in Pediatric Surgery - a National Survey by the Korean Association of Pediatric Surgeons, 2000 - (소아외과의 지수 질환 - 대한소아외과학회 정회원을 대상으로 한 2000년도 전국 조사 -)

  • Lee, M.D.;Kim, S.Y.;Kim, W.K.;Kim, I.K.;Kim, S.C.;Kim, S.K.;Kim, J.E.;Kim, J.C.;Kim, H.H.;Park, K.W.;Park, W.H.;Seo, J.M.;Song, Y.T.;Oh, S.M.;Yoo, S.Y.;Lee, D.S.;Lee, S.K.;Lee, S.C.;Chung, S.Y.;Chung, S.U.;Jung., E.S.;Jung, P.M.;Cho, M.H.
    • Advances in pediatric surgery
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    • v.7 no.2
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    • pp.147-156
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    • 2001
  • Membership qualifications and recognition of the subspecialty training programs by the Korean Association of Pediatric Surgeons(KAPS) have been determined by criteria based on the number of neonatal and total pediatric surgical cases registered, since 1989 (Index cases). The numbers are based on a survey of the 14 founding members of the society by Jung et al. in 1987. The current survey is to review the present status of the index cases from 1997 to 1999 among 36 members of the KAPS. Two surveys were undertaken for this study. In the first survey, cases were collected by the registration form, composed of neonatal(N), important pediatric surgical cases (I), tumor and other similar operations(T) and other common pediatric surgical cases(O). Thirty members responded. and the result was discussed at the Topic Discussion section of the 15th Annual Congress of KAPS, 2000. The second survey analyzed additive data, proposed during discussion at the Congress. Twenty-three members responded. This report is the analysis of the both surveys. The average numbers of the cases/year/surgeon of N, I, T, O and total were 19.5, 51.8, 9.5, 77.1 and 356.5. respectively. The number of index cases(N+I+T)/year/surgeon was 80.8. The ratio of (N+I+T)/total cases was 0.3. Seventeen of 30 members have more than 20 cases of N per year. Twelve members have more than 150 cases, and 13 do more than 100 cases of I per year. Fourteen members have more than 10 cases of T per year. Nineteen and 10 members experienced more than 150 and 100 of index cases(N+I+T) per year. A new list of the index cases and coding system are proposed for the future regular update.

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MMPI and SCL-90-R Profiles in Patients with Sleep-Related Breathing Disorder (수면관련 호흡장애 환자의 MMPI 및 SCL-90-R 반응 특성)

  • Kim, Kyoung-Woo;Yoon, Seok-Joon;Yang, Chang-Kook;Han, Hong-Moo
    • Korean Journal of Psychosomatic Medicine
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    • v.10 no.1
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    • pp.37-47
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    • 2002
  • Objective : Previous studies have suggested an association between sleep-related breathing disorder (SRBD) and several psychological problems, and there were increasing recognition of the link. The purpose of this study is to evaluate the characteristic profiles of MMPI and SCL-90-R in patients with SRBD. Methods : This study consisted of 80 SRBD patients(73 men, 7 women) referred from Sleep Disorder Clinic of Dong-A University Hospital, Busan, Korea. Basic informations including demographic findings and physical examination were collected. Subjects completed the Epworth Sleepiness Scale(ESS), Minnesota Multiphasic Personality Inventory(MMPI), and Symptom Check List-90-Revision (SCL-90-R) prior to standard overnight polysomnography that was performed at hospital sleep laboratory. SRBD was divided into two groups of primary snoring(PS) and obstructive sleep apnea(OSA) according to polysomnographic findings. Results : SRBD showed significant elevation rate of Hs, D, and Hy scales of MMPI and SOM scale of SCL-90-R, which exceeded the rate expected in normal individuals(>5%, 2SD). On comparison of clinical scales of SCL-90-R, OSA group had significantly greater mean score than that of PS group in terms of O-C, DEP, PAR, GSI(p<0.05), SOM and PST(p<0.01). OSA group also showed significantly higher elevation rate in Hs scale of MMPI and SOM scale of SCL-90-R than that of PS. Among OSA group, three scales of MMPI(D, Pt, Si) and three scales of SCL-90-R(ANX, PAR, PSDI) had significant correlation with some PSG variables including total sleep time and sleep efficiency. Among PS group, two scales of MMPI(Hy and Pt), elevation rate of MMPI scales and three scales of SCL-90-R(I-S, PAR, PSDI) had significant correlation with some PSG variables including sleep efficiency, sleep latency and REM sleep percent. Conclusion : The above results suggest that SRBD show neurotic profiles in MMPI and SCL-90-R. This study also clearly indicates that PS group are suffered from clinically meaningful psychiatric symptoms, which are quantitatively lessened but qualitatively similar as compared to that of OSA group.

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