• Title/Summary/Keyword: Internal problems

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Review and application of environmental DNA (eDNA) investigation of terrestrial species in urban ecosystem (도시 내 육상 생물종 모니터링을 위한 환경DNA 리뷰 및 적용)

  • Kim, Whee-Moon;Kim, Seoung-Yeal;Park, Il-Su;Lee, Hyun-Jung;Kim, Kyeong-Tae;Kim, Young;Kim, Hye-Joung;Kwak, Min-Ho;Lim, Tae-Yang;Park, Chan;Song, Won-Kyong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.2
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    • pp.69-89
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    • 2020
  • Scientific trust and quantification of traditional species investigation and results that have been used in ecology for decades has always been a problem and concern for ecologists. Global ecologists have proposed DNA-based species investigation studies to find answers to problems. In this study, we reviewed the global trend of research on environmental DNA(eDNA), which is a method for monitoring species by detecting DNA of organisms naturally mixed in environmental samples such as water, soil, and feces. The first eDNA research confirmed the possibility of species investigation at the molecular level, and commercialization of NGS(Next Generation Sequencing) and DNA metabarcoding elicits efficient and quantitative species investigation results, and eDNA research is increasing in the filed of ecology. In this study, mammals and birds were detected using MiMammal universal primers from 23 samples(3 natural reserves; 20 water bowls) out of 4 patches to verify eDNA for urban ecosystems in Suwon, and eDNA was verified by performing camera trapping and field survey. Most terrestrial species were detected through eDNA, and particularly, mice(Mus musculus), and Vinous-throated Parrotbill (Sinosuthora webbiana) were identified only with eDNA, It has been confirmed to be highly effective by investigating techniques for small and internal species. However, due to the lack of resolution of the primer, weasels(Mustela sibirica) and squirrels(Melanochromis auratus) were not detected, and it was confirmed that the traditional investigation method was effective only for a few species, such as Mogera robusta(Mogera robusta). Therefore, it is judged that the effects of species investigation can be maximized only when eDNA is combined with traditional field survey and Camera trapping to complement each other.

Design of Partial Discharge Pattern Classifier of Softmax Neural Networks Based on K-means Clustering : Comparative Studies and Analysis of Classifier Architecture (K-means 클러스터링 기반 소프트맥스 신경회로망 부분방전 패턴분류의 설계 : 분류기 구조의 비교연구 및 해석)

  • Jeong, Byeong-Jin;Oh, Sung-Kwun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.1
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    • pp.114-123
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    • 2018
  • This paper concerns a design and learning method of softmax function neural networks based on K-means clustering. The partial discharge data Information is preliminarily processed through simulation using an Epoxy Mica Coupling sensor and an internal Phase Resolved Partial Discharge Analysis algorithm. The obtained information is processed according to the characteristics of the pattern using a Motor Insulation Monitoring System program. At this time, the processed data are total 4 types that void discharge, corona discharge, surface discharge and slot discharge. The partial discharge data with high dimensional input variables are secondarily processed by principal component analysis method and reduced with keeping the characteristics of pattern as low dimensional input variables. And therefore, the pattern classifier processing speed exhibits improved effects. In addition, in the process of extracting the partial discharge data through the MIMS program, the magnitude of amplitude is divided into the maximum value and the average value, and two pattern characteristics are set and compared and analyzed. In the first half of the proposed partial discharge pattern classifier, the input and hidden layers are classified by using the K-means clustering method and the output of the hidden layer is obtained. In the latter part, the cross entropy error function is used for parameter learning between the hidden layer and the output layer. The final output layer is output as a normalized probability value between 0 and 1 using the softmax function. The advantage of using the softmax function is that it allows access and application of multiple class problems and stochastic interpretation. First of all, there is an advantage that one output value affects the remaining output value and its accompanying learning is accelerated. Also, to solve the overfitting problem, L2-normalization is applied. To prove the superiority of the proposed pattern classifier, we compare and analyze the classification rate with conventional radial basis function neural networks.

Evaluation of Mechanical Test Characteristics of Fillet Welding (필릿 용접의 기계적 시험 특성 평가)

  • Cho, Byung-Jun;Lee, Soung-Jun;Rhim, Jong-Guk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.535-541
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    • 2020
  • FCAW is used mainly in the welding of carbon steel and alloy steel because it can be welded in all positions and can obtain excellent quality at sites with variable working conditions. Recently, many studies in Korea have estimated the fatigue strength, residual stress, and deformation, and to develop a fillet welding process. On the other hand, there have been few studies of the mechanical properties based on the strength, macro and magnetic particle test results for fillet welding. This study shows the following results through fillet welding, macro testing and strength testing using SM490A (solid-structure rolled steel) for thick plates using SS400 (rolled steel) for the upper plate and FCAW. The hardness test, macro test and magnetic particle test were then conducted. The hardness tests showed that all result values were smaller than the KS B 0893 standard values of 350Hv. The macro-test showed that each type of welded part was in a normal organic state and that there were no internal errors, bubbles, or impurities on the front of the welded part. Therefore, there were no concerns about lamination. The magnetic particle examination showed no problems.

A Standardization Study of the Korean Version of Eating Attitudes Test-26 I : Reliability and Factor Analysis (한국판 식사태도검사-26(The Korean Version of Eating Attitudes Test-26 : KEAT-26) 표준화 연구 I : 신뢰도 및 요인분석)

  • Rhee, Min-Kyu;Lee, Young-Ho;Park, Se-Hyun;Sohn, Chang-Ho;Chung, Young-Cho;Hong, Sung-Kook;Lee, Byung-Kwan;Chang, Phi-Lip;Yoon, A-Rhee
    • Korean Journal of Psychosomatic Medicine
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    • v.6 no.2
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    • pp.155-175
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    • 1998
  • The purpose of this study was to test a reliability and validity of the Korean version of Eating Attitudes Test-26(KEAT-26). Using multi-stage sampling, we finally got 3,496 subjects(1422 males and 2074 females) who were available for analysis from target 4,400 Korean adults over 18 in the nationwide areas of9 kus, 10 middle or small cities, and 17 kuns. We tried to make T score norm of the KEAT-26 as a cutoff score and STEN score norm as a index of severity for disordered eating behaviors. For the male group, Cronhach's internal consistency was .83 and Spearman-Brown split half correlation coefficiency was .75. For the female group, each of them was .81 and .75, and .81, .75 for the grand total group respectively. Validity test was performed by construct validation analysis. By a iterated principal axis factoring, 4 factors were extracted. There were some differences in the factors of the KEAT-26 by sex. In the male group, factor I was 'self-control of eating and bulimic symptom', factor II was 'food preoccupation and dieting', factor III was 'preoccupation with being thinner', factor N was 'avoidance of sweet foods'. In contrast with the male group, factor I was 'self-control of eating and bulimic symptom', factor II was 'preoccupation with being thinner', factor III was 'food preoccupation' and factor N was 'dieting' in the female group. We used T score 65 as a cutoff score. T score 65 corresponded to raw score 19 in the male group, 22 in the female group and 21 in the grand total group. Severity of disordered eating behaviors was measured by a STEN score. In the male group, each of the score range of 0-10, 11-14, 15-18, 19-22 and over 23 represented the degree of none, subclinical, manifest, moderate and severe severity respectively. Each of the score range of 0-13, 14-17, 18-21, 22-26 and over 27 in the female group, and the score range of 0-12, 13-16, 17-20, 21-25 and over 26 in the grand total group also represented the same degree of severity as like in the male group. These results support that KEAT-26 is a reliable and valid scale for evaluating disordered eating behaviors and eating problems.

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Localization Development of Axial Fan for KM-SAM Multi-function radar (KM-SAM 다기능레이더용 축류형 송풍기 국산화 개발)

  • Lee, Gyeong-Chan;Choi, Young-Ho;Lee, Kowan-Woo;Seo, Dae-Sue
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.117-124
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    • 2018
  • This paper describes the localization development of an axial fan for KM-SAM multi-function radar. The multi-function radar, which is constantly affected by the external environment, is a key instrument for detecting and tracking low and medium altitude threat targets. Operating this equipment smoothly requires a fan for controlling the internal temperature and humidity. Presently, all such fans are imported. To solve these problems, localization development research was proposed. The development of localization includes analysis of requirements through review of related technical reports such as original equipment and system equipment specification, prototype design, and verification of design requirement through performance test and environmental test. The study results are described. The blower consisted of an axial fan with guide vanes and the motor was designed to generate a maximum airflow of 970 CFM and a wind pressure of 4.8 IWG. Six prototypes were manufactured for performance evaluation. In addition, for reliable data acquisition, AC power supply, fan performance tester and data acquisition equipment were designed and tested. All prototypes were verified as having design requirements equal to or better than those of imports.

Primiparous Couples' Knowledge, Attitude and Practice regarding Breastfeeding (초산부부의 모유수유에 대한 지식, 태도 및 실천의지)

  • Kang, Nam-Mi
    • Women's Health Nursing
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    • v.5 no.3
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    • pp.379-388
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    • 1999
  • Breastfeeding is an excellent way of feeding infants and continues to be an important source of nutrition and antibodies for infants. Although breast-feeding is believed to be important, the rate of breastfeeding among Korean women is very low. One reason for the low breastfeeding rate is that the health professionals in the past have given little practical help couples to overcome difficulties encountered during breastfeeding. The promotion of breastfeeding has recently become a high priority among health professionals because of the undisputed physiological, psychological, social, economic, and nutritional benefits. Fathers have been found to influence the course of breastfeeding, but no one has conducted a systematic investigation into in and included fathers perspectives of breastfeeding in Korea. It is important to find strategies to solve the problems by assessing the knowledge, attitude and practice of breastfeeding with fathers as well as mothers. The purpose of this research is to find ways to promote primiparous(first child) couples's breastfeeding by assessing their general knowledge, attitude and practice of it. More specifically its purposes is to identify the relationship between knowledge, attitude, practice and the background factors of breastfeeding of primiparous couples in order to promote and support breastfeeding. The data will help health professionals to guide first-pregnancy couples to prepare and overcome any difficulties encountered during breastfeeding. Data were collected through a questionnaire which included both structured and open-ended questions. The questionnaire was composed referencing earlier literature, studies and surveys. This survey was made postpartum 2-3days after childbirth on 96 couples. The numbers of subjects for data analysis were selected 51 couples through pilot screening test. Data were coded and analyzed using the Statistical Package for Social Sciences : Cronbach's alpha coefficient, T-test, ANOVA, Stepwise pearson's correlation coefficient. The relations between the variables of breastfeeding were examined using a Pearson's correlation coefficient. This study showed that, the internal validity of the instrument was tested by Cronbach's alpha. The result was : mother knowledge 0.72, mother attitude 0.88, and father knowledge 0.70, father attitude 0.92, practice 0.76 and planning of breast feeding 0.95. The average age of mothers in the sample was 28.9 years old, and the average age of fathers in the sample was 31.3 years old. The other descriptive informations available included. the study also found that fathers were more important than doctors or nurses. However results of the study indicate that there were no differences between father and mother knowledge of breastfeeding(t=-0.39, p=0.698), and father attitude was statistically significant higher than mother attitude of breastfeeding (t=2.24, p=0.030). In analysis, the variable 'practice' with breastfeeding was the relationship with mother knowledge (p=0.031) and mother attitude(p=0.015). In this study, the correlation between one couple' knowledge and attitude was not significant. Primiparous couples surveyed in the postpartum period regarding knowledge, attitude and practice about breastfeeding might be affected by recall bias, the effects of the euphoria of the first 24-48 hours postpartum, but these variables were not examined. This study results add to the body of knowledge about nursing care for breastfeeding mothers and fathers. This indicates that a need for education about breastfeeding and, that fathers be included in it as well as mothers.

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Characterization of Termite Inhabitation Environment on Wooden Cultural Heritages (목조문화재 흰개미 서식환경 특성 연구)

  • Seo, Min Seok;Jo, Chang Wook;Kim, Soo Ji;Kim, Young Hee;Hong, Jin Young;Lee, Jeung Min;Jeong, So Young
    • Journal of Conservation Science
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    • v.31 no.4
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    • pp.387-393
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    • 2015
  • Damages of wooden cultural heritages caused by various bio-species have been a trend that is increasing on climate change. The decay and bio-damage caused by microbial organisms or insect species are also known to factors of the shape changes and structural problems of wooden cultural heritages. There are so many phenomenons of damage and weathering in wooden cultural heritage for many years and particularly termite can threaten seriously wooden cultural heritage. We investigated with respect to internal and external environment and termite inhabitation around the wooden cultural heritage in Jeollanam-do, Jeollabuk-do, and Jeju-do. As this investigation results, we confirmed that there were the difference in between resident and non-resident about temperature, humidity, moisture contents of wooden building. Resident building is high temperature but humidity and moisture contents is low and these factors are sources of inhabitation condition change about insects as termites. Now we suggest to carry out in parallel to the target wooden cultural heritage and the surrounding habitat for wooden cultural heritage termite damage investigation. Also with the chemical control methods, we must consider necessary to present eco-friendly control management such as construction of heating facilities, residential status, periodic management.

Fabrication and estimation of the plastic detector for measuring the contamination for beta-ray level of the kind of duct waste (배관류 폐기물의 베타선 오염도 측정용 플라스틱 검출기 제작 및 특성평가)

  • Kim Gye-Hong;Oh Won-Zin;Lee Kune-Woo;Seo Bum-Kyoung
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.3 no.3
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    • pp.159-165
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    • 2005
  • The characterization of radiological contamination inside pipes generated during the decommission of a nuclear facility is necessary before pipes can be recycled or disposed. But, existing direct measurements of radioactive contamination level using the survey-meter can not estimate the characteristic of contamination on a local area such as the pipe inside. Moreover, the measurement of surface contamination level using the indirect methods has many problems of an application because of the difficulty of collecting sample and contamination possibility of a worker when collecting sample. In this work, plastic scintillator was simulated by using Monte Carlo simulation method for detection of beta radiation emitted from internal surfaces of small diameter pipe. Simulation results predicted the optimum thickness and geometry of plastic scintillator at which energy absorption for beta radiation was maximized. In addition, the problem of scintillator processing and transferring the detector into the pipe inside was considered when fabricating the plastic detector on the basis of simulation results. The characteristic of detector fabricated was also estimated. As a result, it was confirmed that detector capability was suitable for the measurement of contamination level. Also, the development of a detector for estimating the radiological characteristic of contamination on a local area such as the pipe inside was proven to be feasible.

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Concentration and Properties of Particulate Matters (PM10 and PM2.5) in the Seoul Metropolitan (서울시 지하철 시스템 내의 입자상물질(PM10, PM2.5) 농도 특성)

  • Lee, Tae-Jung;Lim, Hyoji;Kim, Shin-Do;Park, Duck-Shin;Kim, Dong-Sool
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.2
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    • pp.164-172
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    • 2015
  • Seoul subway plays an important part for the public transportation service in Seoul metropolitan area. As the subway system is typically a closed environment, frequent air pollution problems occurred and passengers get malhealth impact. Especially particulate matters (PM) is well known as one of the major pollutants in subway environments. The purpose of this study was to compare the concentrations of $PM_{10}$ and $PM_{2.5}$ in the Seoul subway system and to provide fundamental data in order to management of subway system. $PM_{10}$ and $PM_{2.5}$ samples were collected in the M station platform and tunnel of Subway Line 4 in Seoul metropolitan and in an outdoor location close to it from Apr. 21, 2010~Oct. 27, 2013. The samples collected on teflon filters using $PM_{10}$ and $PM_{2.5}$ mini-volume portable samplers and PM sequential sampler. The PM contributions were $48.6{\mu}g/m^3$ (outdoor), $84.6{\mu}g/m^3$ (platform) and $204.8{\mu}g/m^3$ (tunnel) for $PM_{10}$, and $34.6{\mu}g/m^3$ (outdoor), $49.7{\mu}g/m^3$ (platform) and $83.1{\mu}g/m^3$ (tunnel) for $PM_{2.5}$. The $PM_{10}$ levels inside stations and outdoors are poorly correlated, indicating that $PM_{10}$ levels in the metro system are mainly influenced by internal sources. In this study, we compared PM concentrations before and after operation of ventilation and Electrostatic Precipitator (EP). Despite the increased PM concentration at outdoor, $PM_{10}$ concentration at platform and tunnel showed the 31.2% and 32.3% reduction efficiency after operation the reduction system. The overall results of this study suggest that the installation and operation of the ventilating system and EP should have served as one of the important components for maintaining the air quality in the subway system.

Study on the Development and Application of Image Viewer System (Image Viewer System의 개발 및 적용에 관한 고찰)

  • Yang, Oh-Nam;Seo, In-Ki;Hong, Dong-Ki;Kwon, Kyeong-Tae
    • The Journal of Korean Society for Radiation Therapy
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    • v.18 no.2
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    • pp.67-73
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    • 2006
  • Purpose: The number of patients receiving radiotherapy has increased every year and will keep increasing in the future. Therefore, the technique of radiotherapy is developing from day to day, as a result of it, the quantities of image and data used for radiotherapy are also considerably increasing. Therefore, there have been many difficulties in storing, keeping and managing them. Then, we developed and applied this system for improving complicated work process as well as solving these problems with the collaboration Medical Information Team. Materials and Methods: We exported its image at R & V (Record and Verify: Varis vision, Varian, USA) system and planning system after giving some code to be able to access from management system(RO) for department of radiation oncology to PACS. And, we programmed their information by using necessary information among many information included in DICOM head. Results: All images and data generated by our working environment (Simulation CT, L-gram image and internal body structure, DRR, does distribution )were realized at PACS and it became to be possible for clear image to be printed from any computer in department of radiation oncology. Conclusion: It was inevitable to use film during radiotherapy for patients in the past, however, due to the development of this system, film-less system became to be possible. Therefore, the darkroom space and its management cost in relation to the development process disappeared and it became to be unnecessary for spending tangible and intangible financial expense including human resources, time needed for finding film storing space and film and purchasing separate storing equipment for storing images. Finally, we think this system would be very helpful to handle ail complicated processes for radiotherapy and increasing efficiency of overall working conditions.

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