• 제목/요약/키워드: Meta Search System

검색결과 167건 처리시간 0.02초

클라우드 컴퓨팅 환경에서의 대용량 RDFS 추론을 위한 분산 테이블 조인 기법 (Distributed Table Join for Scalable RDFS Reasoning on Cloud Computing Environment)

  • 이완곤;김제민;박영택
    • 정보과학회 논문지
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    • 제41권9호
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    • pp.674-685
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    • 2014
  • 지식 서비스 시스템이 효과적인 서비스를 제공하기 위해서는, 명시된 지식을 바탕으로 새로운 지식을 추론 할 수 있어야 한다. 대부분 지식 서비스 시스템은 온톨로지로 지식을 표현한다. 실 세계의 지식 정보의 양은 점점 방대해지고 있으며, 따라서 대용량 온톨로지를 효과적으로 추론하는 기법이 요구되고 있다. 본 논문은 클라우드 컴퓨팅 환경을 기반으로 대용량 온톨로지를 RDFS수준으로 추론하기 위한 분산 테이블 조인 방법을 제안하고, 성능을 평가한다. 본 논문에서 제안하는 RDFS 추론은 분산 파일 시스템 환경에서 RDFS 메타 테이블을 기반으로 맵-리듀스를 적용한 방식과, 맵-리듀스를 사용하지 않고 클라우드 컴퓨터의 메모리만 사용한 방식에 초점을 맞추었다. 따라서 본 논문에서는 제안하는 각 기법에 대한 추론 시스템 구조와 RDFS 추론 규칙에 따른 메타 테이블 설계 및 추론 전략 알고리즘에 대해서 중점적으로 설명한다. 제안하는 기법의 효율성을 검증하기 위해 온톨로지 추론과 검색 속도를 평가하는 공식 데이터인 LUBM1000부터 LUBM6000을 대상으로 실험을 수행 하였다. 가장 큰 LUBM6000(8억 6천만 트리플)의 경우, 메타 테이블 기반의 RDFS 추론 기법은 전체 추론 시간이 13.75분(초당 1,042 트리플 추론) 소요된 반면, 클라우드 컴퓨터의 메모리를 적용한 방식은 7.24분(초당 1,979 트리플 추론)이 소모되어 약 2배정도 빠른 추론 속도를 보였다.

Firefighting and Cancer: A Meta-analysis of Cohort Studies in the Context of Cancer Hazard Identification

  • Nathan L. DeBono;Robert D. Daniels ;Laura E. Beane Freeman ;Judith M. Graber ;Johnni Hansen ;Lauren R. Teras ;Tim Driscoll ;Kristina Kjaerheim;Paul A. Demers ;Deborah C. Glass;David Kriebel;Tracy L. Kirkham;Roland Wedekind;Adalberto M. Filho;Leslie Stayner ;Mary K. Schubauer-Berigan
    • Safety and Health at Work
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    • 제14권2호
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    • pp.141-152
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    • 2023
  • Objective: We performed a meta-analysis of epidemiological results for the association between occupational exposure as a firefighter and cancer as part of the broader evidence synthesis work of the IARC Monographs program. Methods: A systematic literature search was conducted to identify cohort studies of firefighters followed for cancer incidence and mortality. Studies were evaluated for the influence of key biases on results. Random-effects meta-analysis models were used to estimate the association between ever-employment and duration of employment as a firefighter and risk of 12 selected cancers. The impact of bias was explored in sensitivity analyses. Results: Among the 16 included cancer incidence studies, the estimated meta-rate ratio, 95% confidence interval (CI), and heterogeneity statistic (I2) for ever-employment as a career firefighter compared mostly to general populations were 1.58 (1.14-2.20, 8%) for mesothelioma, 1.16 (1.08-1.26, 0%) for bladder cancer, 1.21 (1.12-1.32, 81%) for prostate cancer, 1.37 (1.03-1.82, 56%) for testicular cancer, 1.19 (1.07-1.32, 37%) for colon cancer, 1.36 (1.15-1.62, 83%) for melanoma, 1.12 (1.01-1.25, 0%) for non-Hodgkin lymphoma, 1.28 (1.02-1.61, 40%) for thyroid cancer, and 1.09 (0.92-1.29, 55%) for kidney cancer. Ever-employment as a firefighter was not positively associated with lung, nervous system, or stomach cancer. Results for mesothelioma and bladder cancer exhibited low heterogeneity and were largely robust across sensitivity analyses. Conclusions: There is epidemiological evidence to support a causal relationship between occupational exposure as a firefighter and certain cancers. Challenges persist in the body of evidence related to the quality of exposure assessment, confounding, and medical surveillance bias.

원발성 월경통의 추나 치료에 대한 체계적 문헌 고찰 (Chuna Manual Therapy for Primary Dysmenorrhea: A Systematic Review)

  • 서하라;이옥진;이재은;김명규
    • 한방재활의학과학회지
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    • 제27권3호
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    • pp.81-93
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    • 2017
  • Objectives The purpose of this study is to evaluate the effectiveness of Chuna therapy for primary dysmenorrhea. Methods Researchers searched on 7 electronic databases (Pubmed, National Digital Science Library, China National Knowledge Infrastructure, Wangfang med online, Korean Studies Information Service System, Research Information Sharing Service and Oriental medicine Advanced Searching Integrated System). The search included Korean, English, Chinese reports and there was no limit on the search period. All of randomized controlled clinical trials (RCTs) that used Chuna manual therapy for primary dysmenorrhea were selected. Results 27 RCTs met required condition. Meta-analysis showed positive results for Chuna manual therapy for primary dysmenorrhea in terms of therapeutic effects and reduction of symptom scores compared to west medicine, herbal medicine, acupucture and other treatments. Conclusions Above results showed that performing chuna is effective in treating dysmenorrhea. However, in some studies, there was no statistic significance between the experimental group and the control group. Also, according to Cochrane Risk of Bias (RoB) evaluation method, quality of the studies were not high enough. Since most of the materials were in Chinese, more high-quality clinical trials about Chuna therapy for primary dysmenorrhea are needed in Korea.

한방병원에 근무하는 간호사의 정신건강에 대한 연구동향: 국내연구를 중심으로 (Scoping Review of Research on Mental Health of Nurses Working in Korean Medicine Hospitals)

  • 권찬영;박정현;하다정
    • 동의신경정신과학회지
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    • 제32권1호
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    • pp.55-66
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    • 2021
  • Objectives: The aim of this scoping review was to analyze research trends about mental health of nurses working in Korean medicine (KM) hospitals in Republic of Korea. Methods: Searches were conducted using four electronic databases including Oriental Medicine Advanced Searching Integrated System, Korean Studies Information Service System, Research Information Sharing Service, Korea Citation Index to collect relevant studies. The search date was March 4, 2021. All studies published up to the search date were considered. Observational studies reporting mental health outcomes of nurses working at KM Hospital were included. Results: A total of 11 cross-sectional observation studies were included. Four of them compared mental health of nurses working on KM and Western medicine (WM). Commonly reported outcomes related to mental health were job satisfaction, role conflict, and work stress. As a result of meta-analysis based on a 5-point Likert scale, the following factors were related to mental health of KM nurses: job satisfaction (2.844±0.067 points), role conflict (3.678±0.058 points), work stress (3.142±0.021 points), turnover intention (3.483±0.028 points), and burnout (3.180±0.033). Compared to WM nurses, KM nurses had significantly less work stress (p=0.000), role conflict (p=0.039), and job satisfaction (p=0.000). Conclusions: Mental health problems of nurses are known to be very common. Although improving them is an important social task, studies on mental health of KM nurses remain insufficient. Based on findings of this study, more cooperation between nurses and KM doctors should be made to improve the mental health of KM nurses, especially their job satisfaction in the future. The Korean Society of Oriental Neuropsychiatry needs to pay more attention to this topic.

개미 모델 성능에서 다중 에이전트 상호작용 전략의 효과 (The Effect of Multiagent Interaction Strategy on the Performance of Ant Model)

  • 이승관
    • 한국콘텐츠학회논문지
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    • 제5권3호
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    • pp.193-199
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    • 2005
  • 휴리스틱 알고리즘 연구에 있어서 중요한 분야 중 하나가 강화와 다양화의 조화를 맞추는 문제이다. 개미 집단 시스템은 최근에 제안된 조합 최적화문제를 해결하기 위한 메타 휴리스틱 기법으로, 그리디 탐색과 긍정적 보상에 의한 접근법으로 순회 판매원 문제를 풀기 위해 처음으로 제안되었다. 본 논문에서는 기존 개미집단 시스템의 성능을 향상시키기 위해 강화 전략과 다양화 전략으로 나누어진 엘리트 전략을 통해 집단간 긍정적 부정적 상호작용을 수행하는 다중 집단 개미 모델을 제안한다. 그리고, 이 제안된 엘리트 전략에 의한 다중 집단 상호작용 개미 모델을 순회판매원문제에 적용해 보고 그 성능에 대해 기존 개미집단 시스템과 비교한다.

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Comparison of Concurrent Chemoradiotherapy Followed by Adjuvant Chemotherapy Versus Concurrent Chemoradiotherapy Alone in Locoregionally Advanced Nasopharyngeal Carcinoma: a Meta-analysis of 793 Patients from 5 Randomized Controlled Trials

  • Liang, Zhong-Guo;Zhu, Xiao-Dong;Zhou, Zhi-Rui;Qu, Song;Du, You-Qin;Jiang, Yan-Ming
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권11호
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    • pp.5747-5752
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    • 2012
  • Purpose: The main objective of the present study was to evaluate the efficacy and toxicity of concurrent chemoradiotherapy followed by adjuvant chemotherapy compared with concurrent chemoradiotherapy alone in the treatment of locoregionally advanced nasopharyngeal carcinoma. Methods: The search strategy included Pubmed, Embase, the Cochrane Library, China National Knowledge Internet Web, Chinese Biomedical Database and Wanfang Database. We also searched reference lists of articles and the volumes of abstracts of scientific meetings. Randomized controlled trials (RCTs) that compared concurrent chemoradiotherapy followed by adjuvant chemotherapy with concurrent chemoradiotherapy alone in locoregionally advanced nasopharyngeal carcinoma were included. Meta-analysis was performed with RevMan 5.1.0. The Grading of Recommendations Assessment, Development, and Evaluation system (GRADE) was used to rate the level of evidence. Results: Five studies were included. Risk ratios of 1.02 (95%CI 0.89-1.15), 0.93 (95%CI 0.72-1.21), 1.07 (95%CI 0.87-1.32), 0.95 (95%CI 0.80-1.13) were observed for 3 years overall survival, 5 years failure-free survival, 5 years locoregional failure-free survival and 5 years distant metastasis failure-free survival. There were no treatment-related deaths in both groups of five studies. Hematologic and gastrointestinal toxicity were the most significant for patients during adjuvant chemotherapy. The level of evidence was low. Conclusion: Compared with concurrent chemoradiotherapy alone, concurrent chemotherapy followed by adjuvant chemotherapy did not improve prognosis. More toxicity was found during adjuvant chemotherapy.

족관절 염좌의 봉독 약침 치료에 대한 체계적 문헌 고찰 (A Systematic Review of Bee Venom Acupuncture for Ankle Sprain)

  • 구지향;이옥진;조동찬;이은정
    • 한방재활의학과학회지
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    • 제28권3호
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    • pp.55-66
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    • 2018
  • Objectives To evaluate the evidence supporting the effectiveness of bee venom acupuncture for ankle sprain. Methods We conducted search across 11 electronic databases (Pubmed, EMBASE, Cochrane CENTRAL [CENTRAL], KoreaMed, Kmbase, Koreanstudies Information Service System [KISS], National Digital Science Library [NDSL], Korea Institute of Science and Technology Information [KISTI], China National Knowledge Infrastructure [CNKI], Wanfang and Chinese Scientific Journals Database [VIP] database) to find clinical trials that used bee venom acupuncture as treatment for ankle sprain. The methodological quality of randomized controlled clinical trials (RCTs) were assessed using the Cochrane Risk of Bias (RoB) tool, while non-randomized controlled clinical trials (NRCTs) were assessed using the Cochrane Risk of Bias Assessment tool for Non-randomized Study (RoBANS) tool. Results Four RCTs and one nRCT met our inclusion criteria. Almost studies showed that bee venom acupuncture has positive effect on ankle sprain. 4 studies of same intervention and control included in the meta-analysis. When comparing bee venom acupuncture and acupuncture with acupuncture, the effect size of standardized mean difference (SMD) was -0.19 (95% confidence interval [CI]: -1.95~1.56, Z=0.55, p=0.83). And when comparing bee venom acupuncture with acupuncture, the effect size of SMD was -0.17 (95% CI: -0.65~0.31, Z=0.71, p=0.48). Conclusions Although our systematic review found encouraging but limited evidence of bee venom acupuncture for ankle sprain, most of the studies included in the analysis were evaluated as methodologically high risk of bias. From now on further well-designed RCTs should be encouraged.

Hemiarthroplasty for Distal Humerus Fracture: A Systematic Review and Meta-analysis for Functional Outcome

  • Kwak, Jae-Man;Kholinne, Erica;Sun, Yucheng;Lee, Gwan Bum;Koh, Kyoung Hwan;Chun, Jae-Myeung;Jeon, In-Ho
    • Clinics in Shoulder and Elbow
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    • 제21권3호
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    • pp.120-126
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    • 2018
  • Background: Treatment of distal humerus fractures in osteoporotic elderly patients is often challenging. For non-reconstructible fractures with open reduction and internal fixation, total elbow arthroplasty (TEA) is an acceptable alternative. However, the relatively high complication rates and lifelong activity restrictions make TEA less ideal for elderly or low-demand patients. Efforts to identify or develop alternate procedures that benefit relatively young, high-demand patients have resulted in increased interest in hemiarthroplasty. This systematic review reports the clinical outcomes of hemiarthroplasty for distal humeral fractures. Methods: We systematically reviewed the databases of PubMed, Ovid MEDLINE, and Cochrane Library. All English-language studies published before June 2017 were considered for possible inclusion. Search terms included 'distal humerus fracture' and 'hemiarthroplasty'. Studies reporting outcomes (and a minimum of 1 year clinical follow-up) in human subjects after hemiarthroplasty (Latitude system) for distal humeral fractures were assessed for inclusion. Patient demographics, clinical and radiographic outcomes, and complications were recorded, and homogenous outcome measures were analyzed. Results: Nine studies with a total of 115 patients met the inclusion criteria. Among the included studies, the weighted mean follow-up time was 35.4 months. Furthermore, the weighted mean of the postoperative range of motion ($107.6^{\circ}$ flexion-extension, $157.5^{\circ}$ for pronation-supination) and functional outcomes (Mayo elbow performance scores: 85.8, Disabilities of the Arm, Shoulder and Hand score: 19.6) were within the acceptable range. Conclusions: Our study indicates that hemiarthroplasty is a viable option for comminuted distal humerus fracture. Satisfactory functional outcomes were observed in most patients.

Genetic Polymorphism of Interleukin-1A (IL-1A), IL-1B, and IL-1 Receptor Antagonist (IL-1RN) and Prostate Cancer Risk

  • Xu, Hua;Ding, Qiang;Jiang, Hao-Wen
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권20호
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    • pp.8741-8747
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    • 2014
  • Purpose: We aimed to investigate the associations between polymorphisms of interleukin-1A (IL-1A), IL-1B, and IL-1 receptor antagonist (IL-1RN) and prostate cancer (PCa) risk. Materials and Methods: A comprehensive search for articles of MEDLINE and EMBASE databases and bibliographies of retrieved articles published up to August 3, 2014 was performed. Methodological quality assessment of the trials was based on a standard quality scoring system. The meta-analysis was performed using STATA 12.0. Results: We included 9 studies (1 study for IL-1A, 5 studies for IL-1B, and 3 studies for IL-1RN), and significant association was found between polymorphisms of IL-1B-511 (rs16944) as well as IL-1B-31 (rs1143627) and PCa risk. IL-1B-511 (rs16944) polymorphism was significantly associated with PCa risk in homozygote and recessive models, as well as allele contrast (TT vs CC: OR, 0.74; 95%CI, 0.58-0.94; P=0.012; TT vs TC+CC; OR, 0.79; 95%CI, 0.63-0.98; P=0.033; T vs C: OR, 0.86; 95%CI, 0.77-0.96; P=0.008). The association between IL-1B-31 (rs1143627) polymorphism and PCa risk was weakly significant under a heterozygote model (OR, 1.35; 95%CI, 1.00-1.80; P=0.047). Conclusions: Sequence variants in IL-1B-511 (rs16944) and IL-1B-31 (rs1143627) are significantly associated with PCa risk, which provides additional novel evidence that proinflammatory cytokines and inflammation play an important role in the etiology of PCa.

Load Balancing in Cloud Computing Using Meta-Heuristic Algorithm

  • Fahim, Youssef;Rahhali, Hamza;Hanine, Mohamed;Benlahmar, El-Habib;Labriji, El-Houssine;Hanoune, Mostafa;Eddaoui, Ahmed
    • Journal of Information Processing Systems
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    • 제14권3호
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    • pp.569-589
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    • 2018
  • Cloud computing, also known as "country as you go", is used to turn any computer into a dematerialized architecture in which users can access different services. In addition to the daily evolution of stakeholders' number and beneficiaries, the imbalance between the virtual machines of data centers in a cloud environment impacts the performance as it decreases the hardware resources and the software's profitability. Our axis of research is the load balancing between a data center's virtual machines. It is used for reducing the degree of load imbalance between those machines in order to solve the problems caused by this technological evolution and ensure a greater quality of service. Our article focuses on two main phases: the pre-classification of tasks, according to the requested resources; and the classification of tasks into levels ('odd levels' or 'even levels') in ascending order based on the meta-heuristic "Bat-algorithm". The task allocation is based on levels provided by the bat-algorithm and through our mathematical functions, and we will divide our system into a number of virtual machines with nearly equal performance. Otherwise, we suggest different classes of virtual machines, but the condition is that each class should contain machines with similar characteristics compared to the existing binary search scheme.