• Title/Summary/Keyword: problem analysis

Search Result 16,359, Processing Time 0.046 seconds

Thermal Energy Balance Analysis of a Packed Bed for Rock Cavern Thermal Energy Storage (충전층을 이용한 암반공동 열에너지저장시스템의 열에너지 수지 분석)

  • Park, Jung-Wook;Ryu, Dongwoo;Park, Dohyun;Choi, Byung-Hee;Synn, Joong-Ho;Sunwoo, Choon
    • Tunnel and Underground Space
    • /
    • v.23 no.3
    • /
    • pp.241-259
    • /
    • 2013
  • A packed bed thermal energy storage (TES) consisting of solid storage medium of rock or concrete through which the heat transfer fluid is circulated is considered as an attractive alternative for high temperature sensible heat storage, because of the economical viability and chemical stability of storage medium and the simplicity of operation. This study introduces the technologies of packed bed thermal energy storage, and presents a numerical model to analyze the thermal energy balance and the performance efficiency of the storage system. In this model, one dimensional transient heat transfer problem in the storage tank is solved using finite difference method, and temperature distribution in a storage tank and thermal energy loss from the tank wall can be calculated during the repeated thermal charging and discharging modes. In this study, a high temperature thermal energy storage connected with AA-CAES (advanced adiabatic compressed air energy storage) was modeled and analyzed for the temperature and the energy balance in the storage tank. Rock cavern type TES and above-ground type TES were both simulated and their results were compared in terms of the discharging efficiency and heat loss ratio.

Prevalence and Related Factors of Knee Osteoarthritis in Rural Woman (농촌지역 여성들의 무릎 골관절염 유병률 및 관련요인)

  • Kang, Pock-Soo;Kim, Seok-Beom;Lee, Kyeong-Soo;Yun, Sung-Ho
    • Journal of Preventive Medicine and Public Health
    • /
    • v.34 no.4
    • /
    • pp.331-336
    • /
    • 2001
  • Objectives : To assess the prevalence of knee osteoarthritis through proper diagnosis in a rural community and to elucidate the relevant factors of this health problem in order to develop educational methods for the prevention of female knee osteoarthritis as well to provide basic data for prospective research. Methods : Over a period of three months starting from August, 2000, 432 women over the age of 40 and living in a rural area were selected by a multistage cluster sampling method in order to investigate the prevalence of knee osteoarthritis and the related factors. The study utilized interviews and radiological examination. The criteria of knee osteoarthritis used was the American College of Rheumatology classification criteria for osteoarthritis of the knee(1995). Results : The adjusted prevalence of knee osteoarthritis among the subjects was 55.0%, and multiple logistic regression analysis showed that the odds ratio(OR) of knee osteoarthritis among subjects 50-59 years of age and subjects older than 60 years of age as compared to subjects 40-49 years of age were 2.43(95% CI: 1.30-4.70) and 4.40(95% CI: 2.47-7.83), respectively. The OR of knee osteoarthritis among factory workers or farmers as compared to others was 1.79(95% CI: 1.03-3.12). The OR of knee osteoarthritis among subjects who had a family history and subjects who had knee injury or surgical history against those subjects had neither were 2.56(95% CI: 1.42-4.03) and 4.70(95% CI:1.45-15.19), respectively. The OR of knee osteoarthritis among smokers against non smokers was 0.47(95% CI: 0.22-0.97). Conclusions : Related factors of knee osteoarthritis included age, occupation, family history, smoking, knee injury and history of surgery In order to prevent knee osteoarthritis in high risked rural woman, education concerning self-care methods and safety guideline must be provided at the work place by the public and private health sectors. Additionally, these women should be continually encouraged to exercise, including jogging and swimming regularly.

  • PDF

A Study on Collection Development Policy and Guideline Establishment in the Korean University Library (한국 대학도서관의 장서개발정책과 지침작성에 관한 연구)

  • Ryu In-Seok
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.22
    • /
    • pp.109-141
    • /
    • 1992
  • University library must have a substantial collection development policy, by which the short and long term plannings are set up to meet the goals of university education and to support university function. Only when university library organizes collection building based on the well-planned policy, can it establish the systematic collection building, which can satisfy users, support continuity of work, use budget efficiently, and solve the space problem by with-drawing the materials. But most Korean university libraries, contrary to many foreign cases, don't have proper systematic collection development policy or guideline that controls overall library work from planning the collection of materials to evaluating and preserving them. Questionaire on whether university library has collection development policy or guideline was answered positively by only 6 cases out of 57 cases, which is just 10.5 percent. Even in cases that they have a guideline, the content of the copied guideline they sent was confined to acquisition, which is just a part of collection development. Collection development is a statement needed to set up long and short term plannings in consideration of the aims of the library and the needs of users and to shape and manage the library collection systematically. With the above conception and definition, we try to make a proper collection development policy and guideline for the Korean university libraries. Here we must define the object of the university. Object of university is to have good curriculum, good courses, research activities on the part of the faculty, enlargement of graduate school, and establishment of various institutes, etc. And in guideline, selector, method of selection, level of selection and arrangement of budget, etc. must be described concretely in its contents. Since collection development policy and guideline of Korean university libraries should concern their situation, we must confer with the result of the survey and analysis on the matter of collection determination. Here the contents include the priority of materials to be collected, method of collecting materials, arrangement of budget, and others. The purpose of this study is to develop a tenative collection development guideline in reference to the Jeonju University Library by means of analyzing the guiding principle, contents of the guideline, and present conditions of the Korean university libraries. The systematic collection development based on the Guideline for Collection Development of the Korean University Library, can offer a satisfactory service to the users of the university community, and also contribute to the development of the university itself as well as the university library.

  • PDF

Strategies for Improving the Collection and Use of Research Data in the Humanities (인문학 분야 연구데이터의 수집 및 활용성 증진을 위한 전략 연구 - 기초학문자료센터를 중심으로 -)

  • Shim, Wonsik;Ahn, Hye-yeon;Byun, Jeayeon
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.49 no.3
    • /
    • pp.155-183
    • /
    • 2015
  • The rapid growth of information technologies and data networks has increased the volume of data generated from scholarly research and the possibilities of re-using and sharing such data. However, there is a serious problem of management and sharing of research data due to the lack of facilitating policies and supporting infrastructure. In particular, few data repositories exist that support systematic collection and sharing of research data in the humanities. In this regard, the Korea Research Memory (KRM) established by the Korea Research Foundation is a rare exception. The purpose of this research is to present specific processes and strategies that can facilitate the data collection, reuse and preservation through the KRM using task analysis and source document gathering as main focal points. In addition, in order for the effective collection and sharing of research data, the following recommendations are proposed: 1) the need for the adoption of data management plan related policies that govern the collection and sharing of research data generated from publicly funded research projects, 2) the need for training and support services for individual researchers and research institutes, 3) the need for training data specialists, and 4) the citation scheme and structure designed for research data.

A Study on Predictive Traffic Information Using Cloud Route Search (클라우드 경로탐색을 이용한 미래 교통정보 예측 방법)

  • Jun Hyun, Kim;Kee Wook, Kwon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.33 no.4
    • /
    • pp.287-296
    • /
    • 2015
  • Recent navigation systems provide quick guide services, based on processing real-time traffic information and past traffic information by applying predictable pattern for traffic information. However, the current pattern for traffic information predicts traffic information by processing past information that it presents an inaccuracy problem in particular circumstances(accidents and weather). So, this study presented a more precise predictive traffic information system than historical traffic data first by analyzing route search data which the drivers ask in real time for the quickest way then by grasping traffic congestion levels of the route in which future drivers are supposed to locate. First results of this study, the congested route from Yang Jae to Mapo, the analysis result shows that the accuracy of the weighted value of speed of existing commonly congested road registered an error rate of 3km/h to 18km/h, however, after applying the real predictive traffic information of this study the error rate registered only 1km/h to 5km/h. Second, in terms of quality of route as compared to the existing route which allowed for an earlier arrival to the destination up to a maximum of 9 minutes and an average of up to 3 minutes that the reliability of predictable results has been secured. Third, new method allows for the prediction of congested levels and deduces results of route searches that avoid possibly congested routes and to reflect accurate real-time data in comparison with existing route searches. Therefore, this study enabled not only the predictable gathering of information regarding traffic density through route searches, but it also made real-time quick route searches based on this mechanism that convinced that this new method will contribute to diffusing future traffic flow.

Screening of anti-obesity drugs, their analogues and prohibited ingredients in slimming foods (식품 중 부정 혼입된 비만치료제 및 사용금지 성분 실태조사)

  • Yun, Jisuk;Choi, Jangduck;Kwon, Kisung;Jo, Cheon-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.48 no.5
    • /
    • pp.424-429
    • /
    • 2016
  • Globally, obesity has been recognized as a serious health problem. Recently, slimming foods for weight loss and maintenance were found to contain anti-obesity drugs, their analogues, and prohibited ingredients. To avoid inspections by the Government, structurally modified analogs have been continuously synthesized. For rapid determination of adulterated slimming products, we simultaneously analyzed 21 illegal compounds using liquid chromatography (LC) equipped with photo diode array, and LC coupled with tandem mass spectrometry. The validation of the method was performed with regard to selectivity, linearity, limit of detection, limit of quantification, precision, and accuracy. We purchased 128 samples from the Korean market and online sources in the year 2015. In 31 samples, 3 illegal compounds were detected as follows: 9.9-135.3 mg/g of sibutramine, 0.2-17.5 mg/g of yohimbine, and 1.8 mg/g of icariin. This simultaneous detection method might prove to be a simple and rapid analysis for monitoring illegal compounds in slimming foods.

The Single-Session Group Education for Advanced & Terminal Cancer Patients and their Family Members (진행암 및 말기암 환자와 가족을 위한 집단 교육 프로그램)

  • Lee, Young-Sook;Heo, Dae-Seuk;Kim, Mi-Ra;Kim, Won-Gyung;Choi, Jeong-Yun
    • Journal of Hospice and Palliative Care
    • /
    • v.7 no.1
    • /
    • pp.64-72
    • /
    • 2004
  • Purpose: This research aims to assess the effect of a single session of group education of hospice program at Seoul National University Hospital for the advanced and terminal cancer patients and their family members. Methods: Response to questionnaires from 89 participants were evaluated using SAS and CHISQ analysis. The questionnaires included the following items: 1) the characteristics of participants; 2) the characteristics of patients; 3) the difficulties of patient care; 4) the satisfaction with the program Results: The participants consist of 33 patients (37.5%) and 56 family members (56.2%). Diagnosis included mainly stomach, lung, breast, and colon cancer. Participants of family members consisted of spouse, parent, children, daughter-in-law, and siblings (in decreasing order). The participants were interested in the medical information, nutrition, pain and symptom management, and psychosocial adaptation. They had difficulties in emotional problem, nutrition and symptom management. Even though it was a single session of group education, the level of satisfaction was high (95%). Conclusion: This research shows that even the single session of the group education for the advanced and terminal cancer patients and their family members is very helpful by giving them the necessary information. In order to develop comprehensive care-giving services, more specific informations, more opportunities to participate in such sessions and longer question-answer time is required.

  • PDF

Selection of Promising 'Ssam' Vegetable for Summer Production in Highland (고랭지 여름출하용 유망 쌈채소 선발)

  • Jang, Suk-Woo;Kim, Won-Bae;Ryu, Kyoung-Ou
    • Horticultural Science & Technology
    • /
    • v.19 no.2
    • /
    • pp.140-144
    • /
    • 2001
  • Field investigations were initiated to determine possible new 'ssam' vegetable that could be grown during the summer season in highland. Korean 'ssam' means cooked rice in vegetables. The 'ssam' vegetable is called that those leaves has been used for wrapping at meal. Seventeen leafy vegetables were studied, including chard (Beta vulgaris L. var. flavescens DC.), leaf broccoli (Brassica oleracea L. var. italica), Chinese leek (Allium tuberosum Rottl.), Japanese hornwort (Cryptotaenia japonica Hassk), red leaf mustard (Brassica juncea L.), green leaf mustard (Brassica juncea L.), leaf parsley (Petroselinum crispum Nijim), pakchoi (Brassica campestris L. ssp. chinensis Jusl.) tatsoi (Brassica campestris var. narisoma), kale (Brassica oleracea var. acephala), collard (Brassica oleracea var. acephala), Korean mint (Agastache rugosa O. Kuntze), romaine lettuce (Lactuca sativa L. var. longifolia Lam.), red leaf chicory (Cichorium intybus L. var. folisum), red chicory (Cichorium intybus L. var. folisum), green leaf chicory (Cichorium intybus L. var. folisum), and sprouting broccoli (Brassica oleracea L. var. italica). Date of the first harvest in 1999 was July 10th in chard, leaf broccoli, red mustard, mustard, leaf parsley, pakchoi, tatsoi, kale, collard, Korean mint, red leaf chicory, red chicory, green leaf chicory, and sprouting broccoli. Date of the first harvest for Chinese leek, Japanese hornwort, and romaine lettuce was from the middle of June to the late of August. Based on ratings on marketable yield, we found good leaf shape, taste and yield in chard, red leaf mustard, green leaf mustard, pakchoi, tatsoi, romaine lettuce, red leaf chicory, red chicory, and green leaf chicory. Even though the most of all these vegetables were obtained high scores by test panels in shape, taste and quality, but some of them revealed inadequate leaf size as a 'ssam' vegetable. That problem will be solved by control of harvesting time. On the basis of this observation, chard, red leaf mustard, green leaf mustard, pakchoi, tatsoi, romaine lettuce, red leaf chicory, red chicory, and green leaf chicory were rated as promising 'ssam' vegetable by analysis of profits, adaptation, and quality.

  • PDF

Carbapenemase-Producing Klebsiella oxytoca Detection Using Molecular Methods (분자학적 방법을 이용한 Carbapenemase-Producing Klebsiella oxytoca 검출)

  • Yang, Byoung Seon;Park, Ji Ae
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.51 no.4
    • /
    • pp.428-435
    • /
    • 2019
  • The rapid increase and dissemination of carbapene mases, such as Klebsiella pneumoniae carbapenemase (KPC), has become a major problem within the field of healthcare-related infection. There are few antibiotics to treat carbapenem-resistant Enterobacteriaceae (CRE) infections, so the identification of resistant bacterial mechanisms is critical to initiate infection control and conduct epidemiological research. A rapid and effective method for detecting KPC-producing bacteria is needed to avoid therapeutic failures and introduce measures to prevent and control the dissemination of these multi-resistant bacteria. During the study period, 31 isolates (seven isolates of Acinetobacter spp., six isolates of Morganella morganii, five isolates of Pseudomonas aeruginosa, five isolates of Proteus mirabilis, one isolate of Proteus vulgaris, two isolates of Enterobacter cloacae, one isolate of Enterobacter aerogenes, one isolate of Klebsiella pneumoniae, one isolate of Klebsiella oxytoca, one isolate of Serratia marcescens and one isolate of Escherichia coli) were identified by the VITEK. Gram negative rod bacteria were the most frequently isolated from urine (35.5%), blood (19.4%), sputum (16.1%), pus (9.7%), ascitic fluid (9.7%), tracheal aspirates (6.5%) and bile juice (3.2%). Analysis using the PCR method identified the blaKPC gene in the K. oxytoca1 strain, but the blaIMP, blaVIM and blaOXA-48 genes are not amplified. In conclusion, diagnosis using the PCR method can accurately and quickly diagnose KPC, thus establishing quick preventive measures to prevent the spread of KPC in hospitals.

Study on the Analysis of Differential Pressure of the Access Door for a Smoke Control Zone and the Effectiveness of the Measurement Criteria of its Opening Force (제연구역 출입문의 차압 및 개방력 측정기준의 실효성 분석에 관한 연구)

  • Lee, Jae-Ou;Choi, Chung-Seog
    • Fire Science and Engineering
    • /
    • v.26 no.4
    • /
    • pp.24-30
    • /
    • 2012
  • The purpose of this study is to analyze the problem in measuring the differential pressure between the fire area and the neighboring smoke control zone as well as the opening force of a fire door and to present the actual values measured by an objective method. NFSC 501A specifies that the force necessary to open an access door when operating a smoke control system shall be less than 110 N. When the smoke control system does not operate in the space where it is installed, the door opening force can be measured by the test method in KS F 2805. However, when the smoke control system operates, additional opening force is required to overcome the force generated by the differential pressure between the fire area and smoke control room. Therefore, it can be seen that the method proposed by the standard has insufficient reliability. The analog measuring device and digital measuring device showed that the opening forces, $F_a$ and $F_d$, of the fully closed door before the smoke control system were 27.8 N and 27.4 N, respectively. When the door remained open by $5^{\circ}$, the opening forces, $F_a$ and $F_d$, were 33 N and 33.6 N, respectively. When the smoke control system operated and the door was fully closed, the door opening forces, $F_a$ and $F_d$, were 77.6 N and 76.0 N, respectively. Therefore, since the door opening forces are different from the criteria presented by KS F 2805, it is required to review the criteria appropriately.