• 제목/요약/키워드: Analytical Tools

검색결과 354건 처리시간 0.027초

국민건강영양조사 자료의 복합표본설계효과와 통계적 추론 (Complex sample design effects and inference for Korea National Health and Nutrition Examination Survey data)

  • 정진은
    • Journal of Nutrition and Health
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    • 제45권6호
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    • pp.600-612
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    • 2012
  • Nutritional researchers world-wide are using large-scale sample survey methods to study nutritional health epidemiology and services utilization in general, non-clinical populations. This article provides a review of important statistical methods and software that apply to descriptive and multivariate analysis of data collected in sample surveys, such as national health and nutrition examination survey. A comparative data analysis of the Korea National Health and Nutrition Examination Survey (KNHANES) was used to illustrate analytical procedures and design effects for survey estimates of population statistics, model parameters, and test statistics. This article focused on the following points, method of approach to analyze of the sample survey data, right software tools available to perform these analyses, and correct survey analysis methods important to interpretation of survey data. It addresses the question of approaches to analysis of complex sample survey data. The latest developments in software tools for analysis of complex sample survey data are covered, and empirical examples are presented that illustrate the impact of survey sample design effects on the parameter estimates, test statistics, and significance probabilities (p values) for univariate and multivariate analyses.

Key Traffic Metrics as a Basis to Measure Library Performance

  • Udartseva, Olga M.
    • Journal of Information Science Theory and Practice
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    • 제8권2호
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    • pp.55-67
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    • 2020
  • Webometric research in the Russian library sector is just beginning to gain momentum. This article examines the experience of webometric research in libraries from the perspective of the global practice. In particular, it highlights a number of foreign works, which may have a special practical value for Russian libraries, and emphasizes important webometrics areas for libraries. The purpose of this study is to research the practical application of key performance indicators (KPIs) abroad and conduct a webometric analysis of the websites of some leading Siberian and Far Eastern scientific libraries based on selected KPIs. The study data were collected with SimilarWeb and other analytical tools. The study revealed that key traffic metrics are the basis of webometric research, and identified available promising groundwork for the purpose of their further testing. The shortcomings in the current state of the websites of the Siberian and Far Eastern scientific libraries were noted. Based on the obtained webometric traffic indicators, the ranking of the Siberian and Far Eastern scientific libraries was made.

이중모드 스크램제트 엔진 Flowpath 해석 연구 (A Analysis Study of Dual-Mode Scramjet Engine Flowpath)

  • 변종열;안중기
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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    • pp.277-284
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    • 2017
  • 본 연구는 이중모드 스크램제트 엔진의 흡입구, isolator, 연소기, 노즐에서의 flowpath 유동특성에 대한 해석적 연구결과이다. 이중모드 스크램제트 엔진의 설계와 성능을 파악하기 위해서는 공력, 열역학적 특성, 추진 그리고 전체 시스템에 대한 성능 모델과 해석 도구의 개발이 반드시 요구된다. 본 연구에서는 이중모드 스크램제트 엔진의 각 구성품인 흡입구, isolator, 연소기, 노즐에 대한 해석 모델을 정립하고, 개발된 해석 도구를 사용하여 이중모드 스크램제트 엔진의 성능특성을 파악해 보았다.

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Numerical modeling and analysis of RC frames subjected to multiple earthquakes

  • Abdelnaby, Adel E.;Elnashai, Amr S.
    • Earthquakes and Structures
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    • 제9권5호
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    • pp.957-981
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    • 2015
  • Earthquakes occur as a cluster in many regions around the world where complex fault systems exist. The repeated shaking usually induces accumulative damage to affected structures. Damage accumulation in structural systems increases their level of degradation in stiffness and also reduces their strength. Many existing analytical tools of modeling RC structures lack the salient damage features that account for stiffness and strength degradation resulting from repeated earthquake loading. Therefore, these tools are inadequate to study the response of structures in regions prone to multiple earthquakes hazard. The objective of this paper is twofold: (a) develop a tool that contains appropriate damage features for the numerical analysis of RC structures subjected to more than one earthquake; and (b) conduct a parametric study that investigates the effects of multiple earthquakes on the response of RC moment resisting frame systems. For this purpose, macroscopic constitutive models of concrete and steel materials that contain the aforementioned damage features and are capable of accurately capturing materials degrading behavior, are selected and implemented into fiber-based finite element software. Furthermore, finite element models that utilize the implemented concrete and steel stress-strain hysteresis are developed. The models are then subjected to selected sets of earthquake sequences. The results presented in this study clearly indicate that the response of degrading structural systems is appreciably influenced by strong-motion sequences in a manner that cannot be predicted from simple analysis. It also confirms that the effects of multiple earthquakes on earthquake safety can be very considerable.

에드워드 호퍼 회화의 실내공간에 나타난 공간적 특성에 관한 연구 (A Study on the Spatial Characteristics in the Interior Spaces of Edward Hopper's Paintings)

  • 김종진
    • 한국실내디자인학회논문집
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    • 제16권6호
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    • pp.11-18
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    • 2007
  • Edward Hopper is one of the great American artists in the 20th Century. In the field of art, it seems that his paintings are thoroughly analyzed In terms of human alienation and emotional aspects in various ways. However, in his numerous paintings, highly interesting spatial aspects can be found. Purpose of this study is to analyze some of his painting by the spatially analytical tools to examine how his space is experienced. The tools are: relationship between each space, relationship between light and space, and geometrical composition. Among many paintings by Hopper, four of the works that depicted interior spaces are selected and further case-studied in detail: ${\ulcorner}$Rooms by the Sea${\lrcorner}$ (1951), ${\ulcorner}$Sun in an Empty Room${\lrcorner}$ (1963), ${\ulcorner}$New York Movie${\lrcorner}$ (1939) and ${\ulcorner}$Automat${\lrcorner}$ (1927). An Environmental Simulation with scale models was used to examine the relation between light and space. After the research, some unique characteristics of his space were found. Even though his paintings seem to represent the everyday spaces, there are fascinating hidden structure to make people experience in a specific way that Hopper created. Spaces In his paintings do not communicate with each other but are constantly interrupted by the element of time. The mundane everyday world is rediscovered and recreated through these multidimensional and heterogeneous space.

발효식품의 마이크로바이옴 분석 기술 (Analysis techniques for fermented foods microbiome)

  • 차인태;서명지
    • 식품과학과 산업
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    • 제50권1호
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    • pp.2-10
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    • 2017
  • Human have eaten various traditional fermented foods for a numbers of million years for health benefit as well as survival. The beneficial effects of fermented foods have been resulted from complex microbial communications within the fermented foods. Therefore, the holistic approaches for individual identification and complete microbial profiling involved in their communications have been of interest to food microbiology fields. Microbiome is the ecological community of microorganisms that literally share our environments including foods as well as human body. However, due to the limitation of culture-dependent methods such as simple isolations of just culturable microorganisms, the culture-independent methods have been consistently developed, resulting in new light on the diverse non-culturable and hitherto unknown microorganisms, and even microbial communities in the fermented foods. For the culture-independent approaches, the food microbiome has been deciphered by employing various molecular analysis tools such as fluorescence in situ hybridization, quantitative PCR, and denaturing gradient gel-electrophoresis. More recently, next-generation-sequencing (NGS) platform-based microbiome analysis has been of interest, because NGS is a powerful analytical tool capable of resolving the microbiome in respect to community structures, dynamics, and activities. In this overview, the development status of analysis tools for the fermented food microbiome is covered and research trend for NGS-based food microbiome analysis is also discussed.

Development of Analytical Method of Biotin in Complex Drugs and Dietary Supplements Using HPLC-UV

  • Huh, Yoon-Young;Kang, Yun-Pyo;Choi, Yong-Seok;Park, Jeong-Hill;Kwon, Sung-Won
    • Journal of Pharmaceutical Investigation
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    • 제41권1호
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    • pp.25-30
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    • 2011
  • Recently, Korean Food and Drug Administration (KFDA) has focused on developing quality control guidelines for all commercial products in Korea to enforce regulations, improve the quality control, and protect consumers by developing prevalently used and efficient analytical tools to determine and quantify target compounds. Because the Korean Pharmacopeia (KP) presents microbiological assays for biotin, which is laborious and time-consuming, this study is focused on applying HPLC-UV to detect and quantify biotin in complex drugs and dietary supplements like multi-vitamin. Biotin in complex drugs was extracted from methanol and analyzed using mobile phase with 10 mM potassium phosphate (monobasic, pH=3.0) in distilled water and acetonitrile. Gradient condition was used to successfully detect and quantify biotin within 20 minutes. Validation result for linearity was significant that average $r^2$ was 0.999 (n=3) and its relative standard deviation (RSD) was 0.0578% which was less than 2%. Using this method, quantification of biotin in complex drugs was completed successfully and recovery tests were finished that recovery percentage greater than 95% with relative standard deviation less than 2%.

디페메린염산염 시험에 사용되는 유해시약인 수은 대체 시험법의 개발 (Development of alternative titration method without mercuric acetate for the assay of difemerine hydrochloride in Korean Pharmaceutical Codex)

  • 전상설;김경호
    • 분석과학
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    • 제27권4호
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    • pp.196-200
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    • 2014
  • 국가 공정서 중 하나인 대한민국약전외의약품 기준에는 디페메린염산염의 정량법으로 유해시약인 아세트산수은을 사용하는 비수적정법이 수재되어 있다. 본 연구에서는 디페메린염산염의 환경 친화적인 대체 시험법으로 보다 안전하고 효율적인 친환경용매인 에탄올을 사용하는 중화적정법을 개발하고, 분석법을 검증하였다. 디페메린염산염의 직선성은 상관계수(r)가 0.999 이상을 나타내었고, 정확도는 99.10~99.71%, 정밀도는 0.64% 이하로 나타났다. 개발된 시험법은 대한민국약전외의약품 기준의 개정에 기여가 될 것이다.

MIL-STD-188-220의 R-NAD 처리율 분석 (Throughput Analysis of R-NAD in MIL-STD-188-220)

  • 김상수;구성모;임재성
    • 한국군사과학기술학회지
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    • 제17권5호
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    • pp.561-568
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    • 2014
  • The Republic of Korea Army is using R-NAD of MIL-STD-188-220 as a Media Access Control protocol. Under urgent situations, almost all stations transmit data frames and then the network will reach a saturation state. Several articles have been devoted to the study of R-NAD performance. However, most of them focus on comparing the performance of some NADs using network simulation tools. We propose an analytical model to compute the throughput of R-NAD under the assumption of a network traffic saturation. Analytical results were verified by Monte Carlo methods. We have shown that the performance of a success probability and an average idle time remains almost unchanged as the total number of stations increases. We have also shown that Type 1/2/4 operation mode outperforms Type 3 operation mode in throughput. The results showed that the system with a squelch detection achieved a better performance than the one without it. The longer DATA time had a higher throughput.

알루미늄 마이크로 박판소재의 방향성에 관한 실험적 연구 (An experimental study on the oriented mechanical properties of aluminum micro thin foil material)

  • 이혜진;이낙규;최석우;이형욱;최태훈;황재헉;곽동기
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2005년도 추계학술대회 논문집
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    • pp.295-298
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    • 2005
  • This paper is concerned with the precision material property measurement of a micro metal thin foil that is used in MEMS technology. Since these MEMS components require great precision and accuracy, evaluation of reliability such as the lift cycle endurance test, impact test, and residual stress test is necessary for these components. However, in practice, real reliability tests are not easy to perform due to consideration of various factors. Rather than actual testing, it would be much easier to evaluate the reliability of components by the analytical approach. Although the analytical method is utilized by software tools, it is obviously necessary to acquire fundamental properties of materials through real test methods. In this paper, the oriented mechanical properties of aluminum thin foil are measured by nano scale material property measurement system.

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