• 제목/요약/키워드: sensitivity index

검색결과 957건 처리시간 0.028초

수면무호흡증후군의 선별검사로서 임상양상과 산소포화도 이용 (Application of Clinical Features and the Degree of Oxygen Desaturation as a Screening Test for the Obstructive Sleep Apnea Syndrome)

  • 고재광;김인;서광윤;신동균
    • 수면정신생리
    • /
    • 제1권1호
    • /
    • pp.60-67
    • /
    • 1994
  • Objectives: The Obstructive sleep apnea syndrome is characterized by snoring, observed apnea during sleep and excessive daytime sleepiness. The overnight polysomnographic recording is used to investigate patients with possible obstructive sleep apnea syndrome. But the overnight polysomnographic recording is time consuming, expensive, and labor-intensive. Recently in diagnosis of obstructive sleep apnea syndrome, several simple screening tests have been suggested. Methods: This study was performed to assess the probability of application of clinical features and the degree of oxygen desaturation as a screening test for the obstructive sleep apnea syndrome. The sensitivity and specificity of the self-report of clinical features including snoring, observed apnea during sleep, excessive daytime sleepiness and insomnia were tested. And the degree of oxygen desaturation measured by oximetry in 42 subjects were compared with the overnight polysomnographic recording results. Results: In the prediction of apnea index more than 5, the sensitivity of observed apnea during sleep, snoring, excessive daytime sleepiness and insomnia were 96.8%, 93.5%, 38.7%, 25.8% and the specificity of those clinical features were 182%, 36.4%, 100%, 72.7%, respectively. In the prediction of apnea index more than 5, the sensitivity and specificity of the combination of more than three self-report clinical features were 54.8% and 90.9%. The degree of oxygen de saturation and maximal apnea duration in the group of apnea index more than 5 were significantly different from those in the group of apnea index below 5(P<0.001). And the apnea index was significantly correlated with the degree of oxygen desaturation and maximal apnea duration(P<0.001). Conclusion: These results suggest that application of clinical features alone as a screening test for the obstructive sleep apnea syndrome is inadequate because of it's high rate of false positive and false negative results. The degree of oxygen desaturation measured by oximetry is possibly applicable to screening test and follow up evaluation of treatment efficacy for the obstructive sleep apnea syndrome.

  • PDF

풍동실험과 화재실험을 통한 열감지기의 동작특성에 관한 연구 (Study on the Operation Characteristics of Heat Detectors through Fire and Wind Tunnel Experiment)

  • Ryu, Hocheol;Kim, Doohyun
    • 한국재난정보학회 논문집
    • /
    • 제11권2호
    • /
    • pp.203-209
    • /
    • 2015
  • 열감지기는 화재시 발생되는 열을 감지하는 것으로 모든 소방대상물에 일반적으로 사용되는 자동화재탐지설비의 중요한 핵심 요소이다. 열감지기는 스포트(spot)형과 분포형으로 구분되며, 스포트형에는 차동식과 정온식이 있다. 이러한 열감지기는 실제 화재시 작동시간 및 작동온도 등 반응의 민감도에 따라 인명과 재산 손실에 큰 영향을 준다. 국내에서는 스프링클러 헤드제품에 응답시간지수를 도입하여 사용하고 있으나, 열감지기에 대해서는 현재 적용이 되어지지 않고 있으며, 반응의 민감도를 표시하는 응답시간지수의 도입이 필수적으로 본 연구에서는 국내 생산된 정온식 스포트형 열감지기와 다이아프램형 및 반도체 형식의 차동식 스포트형 열감지기에 대하여 풍동실험 및 화재실험을 통하여 응답시간지수, 작동시간, 작동온도 등에 대하여 연구하였다. 응답시간지수를 적용한 열감지기를 설치하여 신속한 경보로 인한 국민의 생명과 재산손실을 줄이는데 도움을 주고자 한다.

사상체질 진단검사를 위한 데이터마이닝 알고리즘 연구 (Data mining Algorithms for the Development of Sasang Type Diagnosis)

  • 홍진우;김영인;박소정;김병철;엄일규;황민우;신상우;김병주;권영규;채한
    • 동의생리병리학회지
    • /
    • 제23권6호
    • /
    • pp.1234-1240
    • /
    • 2009
  • This study was to compare the effectiveness and validity of various data-mining algorithm for Sasang type diagnostic test. We compared the sensitivity and specificity index of nine attribute selection and eleven class classification algorithms with 31 data-set characterizing Sasang typology and 10-fold validation methods installed in Waikato Environment Knowledge Analysis (WEKA). The highest classification validity score can be acquired as follows; 69.9 as Percentage Correctly Predicted index with Naive Bayes Classifier, 80 as sensitivity index with LWL/Tae-Eum type, 93.5 as specificity index with Naive Bayes Classifier/So-Eum type. The classification algorithm with highest PCP index of 69.62 after attribute selection was Naive Bayes Classifier. In this study we can find that the best-fit algorithm for traditional medicine is case sensitive and that characteristics of clinical circumstances, and data-mining algorithms and study purpose should be considered to get the highest validity even with the well defined data sets. It is also confirmed that we can't find one-fits-all algorithm and there should be many studies with trials and errors. This study will serve as a pivotal foundation for the development of medical instruments for Pattern Identification and Sasang type diagnosis on the basis of traditional Korean Medicine.

차량 D 단 소음의 음질 인덱스 및 등급화 구축 (Construction of the Sound Quality Index and Grade at Automotive Level D Noise)

  • 윤태건;박상길;심현진;이정윤;오재응
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
    • /
    • pp.186-189
    • /
    • 2005
  • Since human listening is very sensitive to sound, a subjective index of a sound quality is required. Therefore, in the analysis for each situation, the sound evaluation is composed with sound quality factor. Many researchers spends their effort to make a more reliable and more accurate of sound in term of sound quality index for various system noise. In this study a reliable index is constructed and analyzed using correlation analysis, regression analysis and weighting factor for each sound quality factor. We have made the sound quality index that agrees with more than human subjective sensitivity which apply to various sound quality metrics. Also we applied a 'grade' metric to jury for sound evaluation, analyzed relation between sound duality index and sound quality grade. Then we will judge the sound quality level according to the sound quality grade scheme.

  • PDF

신성장 동력, 소프트웨어산업의 경제적 파급효과 분석 (New Growth Power, Economic Effect Analysis of Software Industry)

  • 최진호;류재홍
    • Journal of Information Technology Applications and Management
    • /
    • 제21권4_spc호
    • /
    • pp.381-401
    • /
    • 2014
  • This study proposes the accurate economic effect (employment inducement coefficient, hiring inducement coefficient, index of the sensitivity of dispersion, index of the power of dispersion, and ratio of value added) of Korea software industry by analyzing the inter-industry relation using the modified inter-industry table. Some previous studies related to the inter-industry analysis were reviewed and the key problems were identified. First, in the current inter-industry table publishedby the Bank of Korea, the output of software industry includes not only the output of pure software industry (package software and IT services) but also the output of non-software industry due to the misclassification of the industry. This causes the output to become bigger than the actual output of the software industry. Second, during rewriting the inter-industry table, the output is changing. The inter-industry table is the table in the form of rows and columns, which records the transactions of goods and services among industries which are required to continue the activities of each industry. Accordingly, if only an output of a specific industry is changed, the reliability of the table would be degraded because the table is prepared based on the relations with other industries. This possibly causes the economic effect coefficient to degrade reliability, over or under estimated. This study tries to correct these problems to get the more accurate economic effect of the software industry. First, to get the output of the pure software section only, the data from the Korea Electronics Association(KEA) was used in the inter-industry table. Second, to prevent the difference in the outputs during rewriting the inter-industry table, the difference between the output in the current inter-industry table and the output from KEA data was identified and then it was defined as the non-software section output for the analysis. The following results were obtained: The pure software section's economic effect coefficient was lower than the coefficient of non-software section. It comes from differenceof data to Bank of Korea and KEA. This study hasa signification from accurate economic effect of Korea software industry.

환경보건적 요소가 도시 내 폭염 취약성 평가 결과에 미치는 영향 분석 (The Impact of Environmental Health Factors on Extreme-heat Vulnerability Assessment in a Metropolitan City)

  • 이원정;강재은;김유근
    • 한국환경보건학회지
    • /
    • 제39권6호
    • /
    • pp.492-504
    • /
    • 2013
  • Objectives: This analysis seeks to evaluate the impact of environmental health factors (EHF; e.g. hospital beds per capita, employees of medical institutions) on extreme-heat vulnerability assessment in Busan Metropolitan City during 2006-2010. Methods: According to the vulnerability concept suggested by the Intergovernmental Panel on Climate Change (IPCC), extreme-heat vulnerability is comprised of the categories of Exposure, Sensitivity, and Adaptive Capacity (including EHF). The indexes of the Exposure and Sensitivity categories indicate positive effects, while the Adaptive capacity index indicates a negative effect on extreme-heat vulnerability. Variables of each category were standardized by the re-scaling method, and then each regional relative vulnerability was computed with the vulnerability index calculation formula. Results: The extreme-heat vulnerability index (EVI) excepting EHF was much higher in urban areas than in suburban areas within the metropolitan area. When EHF was considered, the difference in the EVI between the two areas was reduced due to the increase of the Adaptive capacity index in urban areas. The low EVI in suburban areas was induced by a dominant effect of natural environmental factors (e.g. green area) within the Adaptive capacity category. Conclusions: To reduce the vulnerability to extreme heat in urban areas, which were more frequently exposed to extreme heat than others areas, public health and natural environments need to be improved in sensitive areas.

Heat sensitivity on physiological and biochemical traits in chickpea (Cicer arietinum)

  • Jain, Amit Kumar
    • Advances in environmental research
    • /
    • 제3권4호
    • /
    • pp.307-319
    • /
    • 2014
  • Four chickpea cultivars viz. kabuli (Pusa 1088 and Pusa 1053) and desi (Pusa 1103 and Pusa 547) differing in sensitivity to high temperature conditions were analyzed in earthern pot (30 cm) at different stages of growth and development in the year of 2010 and 2011. Pusa-1053 (kabuli type) showed maximum photosynthetic rate and least by Pusa-547 (desi type), whereas maximum cell membrane thermostability were recorded in Pusa-1103 and minimum in Pusa-1088. Among the treatments, the plants grown under elevated temperature conditions had produced 13.01% more significant data in comparison to plants grown under continuous natural conditions. Stomatal conductance were reduced 44.25% under elevated temperature conditions than natural conditions, whereas 35.56%, when plants grown under initially natural conditions upto 30DAS, then 30-60DAS elevated temperature and finally shifted to natural conditions till harvest. In case of Pusa-1103, stomatal conductance was maximum as compared to rest of 2.7% from Pusa-1053, 8.9% from Pusa-1088, and 10.3% in Pusa-547 throughout the study. Plants grown under continuous elevated temperature conditions had produced 15.30% and 15.32% more significant membrane thermostability index in comparison to continuous natural conditions at vegetative stage and 19.40% and 18.44% at flowering stage, while the better response was recorded at pod formation stage. Pusa-1053 had given 2.8% more membrane thermostability index than Pusa-1088 and Pusa-1103 had given 1.6% more membrane thermostability index than Pusa-547 in the present study. The membrane disruption caused by high temperature may alter water ion and inorganic solutes movement, photosynthesis and respiration. Thus, thermostability of the cell membrane depends on the degree of the electrolyte leakage.

Si3N4 립-광도파로의 두-수평모드 파워결합과 소산파 기반 집적광학 바이오센서 설계 (Design of Integrated-Optic Biosensor Based on the Evanescent-Field and Two-Horizontal Mode Power Coupling of Si3N4 Rib-Optical Waveguide)

  • 정홍식
    • 센서학회지
    • /
    • 제29권3호
    • /
    • pp.172-179
    • /
    • 2020
  • We studied an integrated-optic biosensor configuration that operates at a wavelength of 0.63 ㎛ based on the evanescent-wave and two horizontal mode power coupling of Si3N4 rib-optical waveguides formed on a Si/SiO2/Si3N4/SiO2 multilayer thin films. The sensor consists of a single-mode input waveguide, followed by a two-mode section which acts as the sensing region, and a Y-branch output for separating the two output waveguides. The coupling between the two propagating modes in the sensing region produces a periodically repeated optical power exchanges along the propagation. A light power was steered from one output channel to the other due to the change in the cladding layer (bio-material) refractive index, which affected the effective refractive index (phase-shift) of two modes through evanescent-wave. Waveguide analyses based on the rib optical waveguide dimensions were performed using various numerical computational software. Sensitivity values of 12~23 and 65~165 au/RIU, respectively for the width and length of 4 ㎛, and 3841.46 and 26250 ㎛ of the two-mode region corresponding to the refractive index range 1.36~1.43 and 1.398~1.41, respectively, were obtained.

입원 환자 영양검색 지표 개발 (Development of Nutrition Screening Index for Hospitalized Patients)

  • 김수안;김소연;손정민
    • 대한지역사회영양학회지
    • /
    • 제11권6호
    • /
    • pp.779-784
    • /
    • 2006
  • Several studies about hospital malnutrition have been reported that about more than 40% of hospitalized patients are having nutritional risk factors and hospital malnutrition presents a high prevalence. People in a more severe nutritional status ended up with a longer length of hospital stay and higher hospital cost. Nutrition screening tools identify individuals who are malnourished or at risk of becoming malnourished and who may benefit from nutritional support. For the early detection and treatment of malnourished hospital patients , few valid screening instruments fur Koreans exist. Therefore, the aim of this study was to develop a simple, reliable and valid malnutrition screening tool that could be used at hospital admission to identify adult patients at risk of malnutrition using medical electrical record data. Two hundred and one patients of the university affiliated medical center were assessed on nutritional status and classified as well nourished, moderately or severely malnourished by a Patient-Generated subjective global assessment (PG-SGA) being chosen as the 'gold standard' for defining malnutrition. The combination of nutrition screening questions with the highest sensitivity and specificity at prediction PG-SGA was termed the nutrition screening index (NSI). Odd ratio, and binary logistic regression were used to predict the best nutritional status predictors. Based on regression coefficient score, albumin less than 3.5 g/dl, body mass index (BMI) less than $18.5kg/m^2$, total lymphocyte count less than 900 and age over 65 were determined as the best set of NSI. By using best nutritional predictors receiver operating characteristic curve with the area under the curve, sensitivity and 1-specificity were analyzed to determine the best optimal cut-off point to decide normal or abnormal in nutritional status. Therefore simple and beneficial NSI was developed for identifying patients with severe malnutrition. Using NSI, nutritional information of the severe malnutrition patient should be shared with physicians and they should be cared for by clinical dietitians to improve their nutritional status.

시스템 다이내믹스를 이용한 해운정책이 우리나라 외항선대 증가에 미친 영향에 관한 연구 (Analysis of the Influence of Shipping Policies on the Expansion of Korea's Merchant Fleet Using System Dynamics)

  • 김성범;전준우;여기태
    • 한국항만경제학회지
    • /
    • 제31권2호
    • /
    • pp.23-40
    • /
    • 2015
  • 본 연구는 시스템 다이내믹스 기법을 활용하여 주요 해운정책이 우리나라 외항선대 증가에 미치는 영향에 대하여 분석하는 것을 목적으로 하였다. 시뮬레이션을 위해 사용된 변수는 2005년부터 2013년까지 우리나라 해운기업이 보유한 선박척수와 총톤수, BDI, HRCI, CCFI, WS, 달러 대비 환율, 세계 선대규모, 우리나라 해운업계 부채비율 등이고, 해운정책이 외항선대 증가에 어떤 영향을 주는지를 검증하기 위하여 국제선박등록 톤수, 정책금융기관의 해운기업에 대한 대출액수, 톤세제 적용기업의 수, 선박펀드 규모 등 4가지 정책변수에 대해 민감도 분석을 실시하였다. 예측값의 정확도를 파악하기 위해 절대평균 오차비율(MAPE) 검증을 실시하였는데, MAPE 값이 3.46%로서 10%이내에 해당하여 매우 높은 정확도를 가지는 시뮬레이션 모델로 평가되었다. 민감도 분석결과, 국제선박등록 톤수, 정책금융기관의 대출액수, 선박펀드 규모, 톤세제 적용기업의 수의 순으로 영향도가 큰 것으로 분석되었다.