• 제목/요약/키워드: Performance-based Statistics

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교원능력개발평가 영양교사 평가지표와 문항의 중요도 및 수행도에 대한 영양교사들의 인식 (Nutrition Teachers' Perception of the Importance and Performance Frequency of Their Roles in the Indicators and Items on a Teacher Evaluation)

  • 최희준;박지혜
    • 대한영양사협회학술지
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    • 제16권2호
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    • pp.146-159
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    • 2010
  • This study was conducted to determine the appropriateness of the indicators and items on teacher evaluations for professional development and to provide insight for their improvement. To accomplish this, the perception of the importance and performance frequency of 318 nutrition teachers regarding their roles inherent in the indicators and items were evaluated through a survey questionnaire based on a five-point Likert scale. The quantitative data were analyzed using descriptive statistics and a paired t-test. In addition, the reflective analysis and constant comparison method were employed to analyze the responses to the open-ended questions asking problems in the indicators and items. The results revealed that the mean scores for the importance and performance frequency of most indicators and items were over four points, which implies that most indicators and items are appropriate for evaluating the job tasks of nutrition teachers. However, it was suggested that a few items be revised or removed for their improvement and appropriateness. This study concluded that nutrition teachers should have more chances to provide nutrition education for students to enable them to perform as teachers and not simply dietitians.

하드웨어 Trojan 사례 연구: 캐시 일관성 규약을 악용한 DoS 공격 (A Case Study on Hardware Trojan: Cache Coherence-Exploiting DoS Attack)

  • 공선희;홍보의;서태원
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2015년도 추계학술발표대회
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    • pp.740-743
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    • 2015
  • The increasing complexity of integrated circuits and IP-based hardware designs have created the risk of hardware Trojans. This paper introduces a new type of threat, the coherence-exploiting hardware Trojan. This Trojan can be maliciously implanted in master components in a system, and continuously injects memory read transactions on to bus or main interconnect. The injected traffic forces the eviction of cache lines, taking advantage of cache coherence protocols. This type of Trojans insidiously slows down the system performance, incurring Denial-of-Service (DoS) attack. We used Xilinx Zynq-7000 device to implement and evaluate the coherence-exploiting Trojan. The malicious traffic was injected through the AXI ACP interface in Zynq-7000. Then, we collected the L2 cache eviction statistics with performance counters. The experiment results reveal the severe threats of the Trojan to the system performance.

Effects of nursing record education focused on legal aspects at small and medium sized hospitals

  • Do, Taehee;Kim, Heejung
    • 한국간호교육학회지
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    • 제27권2호
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    • pp.152-162
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    • 2021
  • Purpose: The purpose of this study was to examine the effect of nursing record education on the knowledge and performance of nursing record of nurses at small- and medium-sized hospitals. Methods: The participants were 62 nurses working in two small- and medium-sized hospitals. Thirty-two nurses comprised the experimental group, and 30 nurses comprised the control group. Nursing record education was provided for the experimental group. Data were analyzed by x2-test and t-test analysis using the IBM SPSS statistics 25.0 Program. Results: After education, the knowledge (t=2.43, p=.019), performance (t=2.19, p=.033) and behavior scores (t=2.42, p=.018) on nursing record were significantly higher in the experimental group than in the control group. Based on this result, nursing record education is an effective intervention to improve nurses' knowledge and performance in writing nursing records in small- and medium-sized hospitals. Conclusion: We suggest the development of a systematic and standardized education program on nursing record including its legal aspects, for nurses in small- and medium-sized hospitals. The results of this study can be used as basic data for developing a nursing record education program for small- and medium-sized hospitals.

풍력발전기의 하중 측정을 위한 해석 소프트웨어의 개발 (Development of an Analysis Software for the Load Measurement of Wind Turbines)

  • 길계환;방제성;정진화
    • 풍력에너지저널
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    • 제4권1호
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    • pp.20-29
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    • 2013
  • Load measurement, which is performed based on IEC 61400-13, consists of three stages: the stage of collecting huge amounts of load measurement data through a measurement campaign lasting for several months; the stage of processing the measured data, including data validation and classification; and the stage of analyzing the processed data through time series analysis, load statistics analysis, frequency analysis, load spectrum analysis, and equivalent load analysis. In this research, we pursued the development of an analysis software in MATLAB to save labor and to secure exact and consistent performance evaluation data in processing and analyzing load measurement data. The completed analysis software also includes the functions of processing and analyzing power performance measurement data in accordance with IEC 61400-12. The analysis software was effectively applied to process and analyse the load measurement data from a demonstration research for a 750 kW direct-drive wind turbine generator system (KBP-750D), performed at the Daegwanryeong Wind Turbine Demonstration Complex. This paper describes the details of the analysis software and its processing and analysis stages for load measurement data and presents the analysis results.

앙상블 SVM 모형을 이용한 기업 부도 예측 (Bankruptcy prediction using ensemble SVM model)

  • 최하나;임동훈
    • Journal of the Korean Data and Information Science Society
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    • 제24권6호
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    • pp.1113-1125
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    • 2013
  • 기업의 부도를 예측하는 것은 회계나 재무 분야에서 중요한 연구주제이다. 지금까지 기업 부도예측을 위해 여러 가지 데이터마이닝 기법들이 적용되었으나 주로 단일 모형을 사용함으로서 복잡한 분류 문제에의 적용에 한계를 갖고 있었다. 본 논문에서는 최근에 각광받고 있는 SVM (support vector machine) 모형들을 결합한 앙상블 SVM 모형 (ensemble SVM model)을 부도예측에 사용하고자 한다. 제안된 앙상블 모형은 v-조각 교차 타당성 (v-fold cross-validation)에 의해 얻어진 여러 가지 모형 중에서 성능이 좋은 상위 k개의 단일 모형으로 구성하고 과반수 투표 방식 (majority voting)을 사용하여 미지의 클래스를 분류한다. 본 논문에서 제안된 앙상블 SVM 모형의 성능을 평가하기 위해 실제 기업의 재무비율 자료와 모의실험자료를 가지고 실험하였고, 실험결과 제안된 앙상블 모형이 여러 가지 평가척도 하에서 단일 SVM 모형들보다 좋은 성능을 보임을 알 수 있었다.

한국과 일본 장기요양시설 공급과 이용의 지역 간 변이 (Variations and Factors Associated with the Supply and Utilization of Nursing Home Services in Japan and South Korea)

  • 김홍수;윤난희;이세윤
    • 보건행정학회지
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    • 제30권1호
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    • pp.100-111
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    • 2020
  • Background: Few studies have examined the performance of the public long-term care insurance (LTCI) from the perspective of geographic equity. This study investigated regional variations and associated factors in the supply and utilization of nursing home care within and also between Japan and Korea. Methods: A comparative dataset was developed by extracting data from 2013-2015 LTCI statistics yearbooks and Organization for Economic Cooperation and Development regional statistics, as well as other comparable data in Japan and Korea. The unit of analysis was the prefecture in Japan and the province in Korea. We computed variation indices and conducted regression analyses for regional variations within each country and decomposition analyses to examine the variations between the countries. Results: The overall regional supply and use of nursing home care were higher in Japan, but the regional variations in Korea were larger than in Japan. In both countries, the nursing home supply was negatively associated with the proportion of older people with independent living. Nursing home use was also negatively associated with the supply of hospital beds and home care agencies in Korea; the relationship was the opposite in Japan, however. The country-based differences were more likely to be explained by differences in the distributions of the variables included in the analytical model than country-specific characteristics. Conclusion: Regional-level nursing home supply and use were unequal in both countries, and the contributing factors were not the same. Policy efforts are needed to advance regional equality in long-term care (LTC) and collaboration between health and LTC institutions for frail older people, especially in Korea.

협업필터링과 스태킹 모형을 이용한 상품추천시스템 개발 (Development of Product Recommender System using Collaborative Filtering and Stacking Model)

  • 박성종;김영민;안재준
    • 융합정보논문지
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    • 제9권6호
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    • pp.83-90
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    • 2019
  • 사람들은 자신의 더 나은 선택을 위하여 끊임없이 노력한다. 이러한 이유로 추천시스템이 개발되었으며, 1990년대 초반부터 계속해서 발전하고 있다. 그 중, 협업필터링 기법은 추천시스템 분야에서 우수한 성능을 보였으며, 기계학습이 등장하면서 기계학습을 이용한 추천시스템에 관한 연구가 활발히 진행되었다. 본 연구는 앙상블 방법 중에서 스태킹 모형을 사용하여 추천시스템을 구축하며, 실제 고객의 상품 구매 데이터를 활용하여 협업필터링과 기계학습 기반 스태킹 모형으로 추천시스템을 개발하였다. 제시한 모형의 추천 성능은 기존의 협업필터링과 기계학습 기반 추천시스템과 비교하여 모형의 우수성을 확인하며, 연구결과는 스태킹 모형을 이용한 추천시스템 모형의 추천 성능이 개선됨을 확인하였다. 향후 본 연구에서 제안한 모형은 개인이나 기업이 더 나은 선택을 하여 상품을 추천할 때 도움을 줄 것으로 기대한다.

병원 성과 비교를 위한 급성기 뇌졸중 사망률 위험보정모형의 타당도 평가 (Evaluation of the Validity of Risk-Adjustment Model of Acute Stroke Mortality for Comparing Hospital Performance)

  • 최은영;김선하;옥민수;이현정;손우승;조민우;이상일
    • 보건행정학회지
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    • 제26권4호
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    • pp.359-372
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    • 2016
  • Background: The purpose of this study was to develop risk-adjustment models for acute stroke mortality that were based on data from Health Insurance Review and Assessment Service (HIRA) dataset and to evaluate the validity of these models for comparing hospital performance. Methods: We identified prognostic factors of acute stroke mortality through literature review. On the basis of the avaliable data, the following factors was included in risk adjustment models: age, sex, stroke subtype, stroke severity, and comorbid conditions. Survey data in 2014 was used for development and 2012 dataset was analysed for validation. Prediction models of acute stroke mortality by stroke type were developed using logistic regression. Model performance was evaluated using C-statistics, $R^2$ values, and Hosmer-Lemeshow goodness-of-fit statistics. Results: We excluded some of the clinical factors such as mental status, vital sign, and lab finding from risk adjustment model because there is no avaliable data. The ischemic stroke model with age, sex, and stroke severity (categorical) showed good performance (C-statistic=0.881, Hosmer-Lemeshow test p=0.371). The hemorrhagic stroke model with age, sex, stroke subtype, and stroke severity (categorical) also showed good performance (C-statistic=0.867, Hosmer-Lemeshow test p=0.850). Conclusion: Among risk adjustment models we recommend the model including age, sex, stroke severity, and stroke subtype for HIRA assessment. However, this model may be inappropriate for comparing hospital performance due to several methodological weaknesses such as lack of clinical information, variations across hospitals in the coding of comorbidities, inability to discriminate between comorbidity and complication, missing of stroke severity, and small case number of hospitals. Therefore, further studies are needed to enhance the validity of the risk adjustment model of acute stroke mortality.

VGG-based BAPL Score Classification of 18F-Florbetaben Amyloid Brain PET

  • Kang, Hyeon;Kim, Woong-Gon;Yang, Gyung-Seung;Kim, Hyun-Woo;Jeong, Ji-Eun;Yoon, Hyun-Jin;Cho, Kook;Jeong, Young-Jin;Kang, Do-Young
    • 대한의생명과학회지
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    • 제24권4호
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    • pp.418-425
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    • 2018
  • Amyloid brain positron emission tomography (PET) images are visually and subjectively analyzed by the physician with a lot of time and effort to determine the ${\beta}$-Amyloid ($A{\beta}$) deposition. We designed a convolutional neural network (CNN) model that predicts the $A{\beta}$-positive and $A{\beta}$-negative status. We performed 18F-florbetaben (FBB) brain PET on controls and patients (n=176) with mild cognitive impairment and Alzheimer's Disease (AD). We classified brain PET images visually as per the on the brain amyloid plaque load score. We designed the visual geometry group (VGG16) model for the visual assessment of slice-based samples. To evaluate only the gray matter and not the white matter, gray matter masking (GMM) was applied to the slice-based standard samples. All the performance metrics were higher with GMM than without GMM (accuracy 92.39 vs. 89.60, sensitivity 87.93 vs. 85.76, and specificity 98.94 vs. 95.32). For the patient-based standard, all the performance metrics were almost the same (accuracy 89.78 vs. 89.21), lower (sensitivity 93.97 vs. 99.14), and higher (specificity 81.67 vs. 70.00). The area under curve with the VGG16 model that observed the gray matter region only was slightly higher than the model that observed the whole brain for both slice-based and patient-based decision processes. Amyloid brain PET images can be appropriately analyzed using the CNN model for predicting the $A{\beta}$-positive and $A{\beta}$-negative status.

시계열 모형을 이용한 단기 풍력발전 예측 연구 (A study on short-term wind power forecasting using time series models)

  • 박수현;김삼용
    • 응용통계연구
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    • 제29권7호
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    • pp.1373-1383
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    • 2016
  • 풍력에너지 산업이 발전하고 풍력발전에 대한 의존율이 높아짐에 따라 안정적인 공급이 중요해지고 있다. 원활한 전력수급계획을 세우기 위해서 풍력발전량을 정확히 예측하는 것이 중요하다. 본 논문에서는 강원도 평창 횡계리에 설치된 대관령 2풍력(2MW 1기)의 시간별 풍력발전 데이터와 강원도 대관령 기상대에서 관측되는 시간별 풍속과 풍향 데이터를 기상청 지상관측자료에서 수집하여 연구하였다. 풍력발전량 예측을 위하여 신경망 모형과 시계열 모형인 ARMA, ARMAX, ARMA-GARCH, Holt Winters 모형을 비교하였다. 모형 간 예측력을 비교하기 위해 mean absolute error(MAE)를 사용하였다. 모형의 예측 성능 비교 결과 1시간에서 3시간의 단기 예측에 있어서 ARMA-GARCH 모형이 우수한 예측력을 보였다. 6시간 이후 예측에서는 신경망 모형이 우수한 예측을 보였다.