• 제목/요약/키워드: Trend comparison

검색결과 935건 처리시간 0.022초

증발계 증발량의 시계예 및 통계적 특성 분석 (Analysis of the Statistical and Time-Series Characteristics for Pan Evaporation)

  • 구자웅
    • 한국농공학회지
    • /
    • 제19권3호
    • /
    • pp.4472-4482
    • /
    • 1977
  • In order to estimate furture consumtive use, some statistical characteristics of 22-year pan evaporation data at four selected stations were calculated in this study. Districal distribution, trend analysis and time-series, statistical and periodic analysis for annual, monethly and ten-day values were performed in the statistical analysis. The stations are Seoul, Taeku, Jeonju and Mokpo for monthly data, and Suweon data are compared to the reported Penman values. The results are as followed: 1. Annual evaporation ranged to 990-1,375mm varying with the locations of the stations. The Districal distribution of evaporation in the Republic is shown in Fig. 1. 2. The trend analysis for annual evaporation resulted in detail in Table 2 and Fig. 2, through simple moving average methods. The results show relatively short-period data of about 10 years would be acceptable for field use. 3. The means and dispersions of monthly evaporation at four stations are detailed in Table 3. 4. The monthly evaporation approached to the trend of normal distribution Fig. 3 showed the examples of normal distribution for each typical monthly data. 5. The correlograms detailed in Fig. 4, shows the time-series characteristics of monthly evaporation, whose periodic term should be twelve months. 6. The periodic analysis for monthly evapolation results in Table 4. Fig. 5 shows the comparison of estimated values to actual and the trend approaches Shuster's periodic trend. 7. A periodic description of days after March 1 for irrigation periods was developed to predict ten-day evaporation in Fig. 6. The ten-day etraporation is different in the distribution form and occurence period of maximum values from the reported Penman's man's evapotranspiration.

  • PDF

한국의 우주발사체 산업 발전을 위한 우주발사서비스 시장진입 전략 평가 (Trend Analysis based Strategy Evaluation for Launch Vehicle Industry in Korea)

  • 홍슬기;안재명
    • 한국항공우주학회지
    • /
    • 제43권10호
    • /
    • pp.936-942
    • /
    • 2015
  • 국가위상 제고와 국내 발사체산업 발전에 따른 경제 발전을 위하여 우주발사서비스 시장진입은 필수적이다. 발사체 개발의 후발주자로써 시장에 효과적으로 진입하기 위해서는 시장의 트렌드를 정확하게 파악하고, 체계적인 시장진입전략을 수립하여야한다. 본 논문에서는 세계 우주발사서비스 시장의 3가지 핵심트렌드(고성능의 대형 우주발사체 수요 증가, 저가형 우주발사체 증가, Dual/Multi-Launch 증가)를 도출하고, 각 핵심트렌드에 대응하기 위한 전략의 우선순위를 쌍대비교분석법을 통해 평가하였다. 그 결과 모든 트렌드 하에서 발사체 신뢰성 확보 전략이 가장 중요하며, 고성능의 대형 우주발사체 수요 증가 트렌드 하에서는 정부 지원 전략이, 저가형 우주발사체 및 Dual/Multi-Launch 증가 트렌드 하에서는 가격 경쟁력 확보전략이 두 번째 우선순위를 보였다.

Trends and Issues in the Research of Chinese Educational Technology

  • ZHAO, Hai Lan
    • Educational Technology International
    • /
    • 제6권2호
    • /
    • pp.87-100
    • /
    • 2005
  • The purpose of this study lies in touching the study trend of Chinese education technology through the analysis on present situation of the study in Chinese education technology, and is to suggest the direction for the its further study and development. In order to achieve these kinds of study purpose, the frames have been set to grasp the features and trend of Chinese educational technology in such as 4 aspects of educational technology definition, curriculum and the cultivation of genuine individuals, study zone aspect and the method, and in order to grasp, in the comparison with the countries of advanced educational technology such as Korea, America etc., the progressive features and the trend of development of Chinese educational technology have been analyzed. As a result of the analysis, it has been found that Chinese educational technology has the different features in the study and development of educational technology of Korea and America in the abovementioned 4aspects. First, in the education technology comprehension, it differs from Korea, Japan and America, and understands the technology as a skill. Consequently, in either study or actuality, it seems puts more emphasis on skills (moreover, the aspect of hardware). Second, in the aspect of curriculum and the cultivation of the genuine individuals, gives preponderance to science aspect, and the unclear distinction between the education technology and the computer science makes that the true character of educational technology is not clear. Third, when speaking of study fields and study methods, those of china is a little behind of the advanced nations of the educational engineering, Korea, America and so on. And in the range of study, China is following the international tendency but when it comes to the depth of study and quality is very far from perfect. In the aspect of study method, the theoretical study, design study and development study are occupying mostly, and it is hardly to see the existence about actual proof study, and in this aspect, it is quite different than that of Korea and America. And it is judged that it is related with the traditional educational ideology and the academic study tradition, the cultural air and the features of economical development of China.

Trend Analysis in the Prevalence of Type 2 Diabetes According to Risk Factors among Korean Adults: Based on the 2001~2009 Korean National Health and Nutrition Examination Survey Data

  • Kim, Young-Ju;Lim, Myoung-Nam;Lee, Dong-Suk
    • 대한간호학회지
    • /
    • 제44권6호
    • /
    • pp.743-750
    • /
    • 2014
  • Purpose: The objective of this study was to provide a trend analysis of the prevalence of diabetes relative to the socioeconomic, lifestyle, and physiologic risk factors among Korean adults aged over 30 years for a 10-year period using data from the Korean National Health and Nutrition Examination Survey. Methods: Prevalence difference and the slope index of inequality were calculated for each risk factors using binomial regression by considering the repeated cross-sectional features of the data. The prevalence ratio and the relative index of inequality were calculated using log-binomial regression. Linear trend tests were performed using SAS 9.2. Results: Crude prevalence of diabetes increased over the 10-year period, and was higher for men than for women. It was very high for adults 60 years or over, consistently increasing over time. The prevalence among unemployed men, women with higher level of stress, women with hypertension, and adults with serum triglyceride levels over 135 mg/dL increased over the 10-year period in comparison with the respective control group. Conclusion: Considering the rapid economic development and associated lifestyle changes in Korea, action should be taken to control the prevalence of diabetes by both preventing and consistently monitoring these identified risk factors using a public-health approach.

구간 고장 데이터가 주어진 수리가능 시스템의 신뢰도 분석절차 개발 및 사례연구 (Development of Reliability Analysis Procedures for Repairable Systems with Interval Failure Time Data and a Related Case Study)

  • 조차현;염봉진
    • 한국군사과학기술학회지
    • /
    • 제14권5호
    • /
    • pp.859-870
    • /
    • 2011
  • The purpose of this paper is to develop reliability analysis procedures for repairable systems with interval failure time data and apply the procedures for assessing the storage reliability of a subsystem of a certain type of guided missile. In the procedures, the interval failure time data are converted to pseudo failure times using the uniform random generation method, mid-point method or equispaced intervals method. Then, such analytic trend tests as Laplace, Lewis-Robinson, Pair-wise Comparison Nonparametric tests are used to determine whether the failure process follows a renewal or non-renewal process. Monte Carlo simulation experiments are conducted to compare the three conversion methods in terms of the statistical performance for each trend test when the underlying process is homogeneous Poisson, renewal, or non-homogeneous Poisson. The simulation results show that the uniform random generation method is best among the three. These results are applied to actual field data collected for a subsystem of a certain type of guided missile to identify its failure process and to estimate its mean time to failure and annual mean repair cost.

노인주거관련연구의 한.미 .일 비교 ( I ) - 일본의 경우 - (Comparison about the Study of elderly housing in Korea , U.S.A. and Japan ( I ) -Focusing on Japan)

  • 신경주
    • 한국주거학회논문집
    • /
    • 제5권1호
    • /
    • pp.1-7
    • /
    • 1994
  • The purpose of this study was to investigate the difference in the trend of the study of elderly housing for the suggestion of the direction in Korea. This study was the first series about the study of elderly housing and analysed the 164 pieces of researches in Japan. The data were analysed classification with contents first, then examined the class in chronological order, and suggest the trend in the study of elderly housing in Japan. 1. The study of elderly facilities was reported the highest interest and was completed in the latter half of the 1980s except the payment elderly home in Japan. 2. Their second interest was the study of general elderly housing. Rural elderly facilities as a local elderly housing were researched frequently. 3. The study of housing for three generation was studied much in early 1980s, but decreased concerns these days. The study of housing for the elderly was studied the latter of 1980s and concerns were sustained. 4. Trend of the study of elderly housing was classified as follows; 1950s was the stage of unconsciousness, 1960s was the stage of sprout, 1970s was the stage of blossom, 1980s was the stage in full bloom and then the study was peak in 1986 and slowly decrease the concern. 5. In 1990s the study of elderly housing was moved into elderly facilities in a consumer's view and older people's life their family relation.

  • PDF

2013년 태풍에 대한 수치모델들의 강도 예측성 평가 (Evaluation of the Intensity Predictability of the Numerical Models for Typhoons in 2013)

  • 김지선;이우정;강기룡;변건영;김지영;윤원태
    • 대기
    • /
    • 제24권3호
    • /
    • pp.419-432
    • /
    • 2014
  • An assessment of typhoon intensity predictability of numerical models was conducted to develop the typhoon intensity forecast guidance comparing with the RSMC-Tokyo best track data. Root mean square error, box plot analysis and time series of wind speed comparison were performed to evaluate the each model error level. One of noticeable fact is that all models have a trend of error increase as typhoon becomes stronger and the Global Forecast System showed the best performance among the models. In the detailed analysis in two typhoon cases [Danas (1324) and Haiyan (1330)], GFS showed good performance in maximum wind speed and intensity trend in the best track, however it could not simulate well the rapid intensity increasing period. On the other hand, ECMWF and Hurricane-WRF overestimated the typhoon intensity but simulated track trend well.

교사재배치(校舍再配置)를 위한 초등학교(初等學校) 특별교실(特別敎室) 선호경향(選好傾向) 비교(比較) - 광주광역시(光州廣域市) 교사재배치(校舍再配置) 대상(對象) 초등학교(初等學校)를 중심(中心)으로 - (A Comparison on the Trend of Preference about Classroom for Special Purposes Related with School Relocation in Elementary School - Concentrated on the relocation-needed elementary schools in Kwangju city -)

  • 정주성;최병관;박영숙
    • 교육시설
    • /
    • 제9권2호
    • /
    • pp.15-24
    • /
    • 2002
  • This study is performed to understand a trend of preference about classroom for special purposes related with elementary school relocation. It is anayzed based on the questionnaire of teachers at work in the two schools having similar educational environment. The results showed that it is desirable to locate rooms for science or practice in low story and music room in the lowermost or uppermost story. Rooms for art, linguistic education and computer had not limited any place. It is shown that the scale of each preparation room is significantly different with each grade and more large scale is needed in higher grade. These results reflect that the present arrangement of classrooms for special purposes is not adequate and require more reasonable arrangement with the grade in the architectural plans for relocation-needed elementary schools.

EVALUATION OF "INCREASING TREND" IN SEAWIFS-OBSERVED ANGSTROM EXPONENT DURING 1998-2006 OVER EAST-ASIAN WATERS

  • Fukushima, Hajime;Ogata, Kazunori;Li, Liping
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
    • /
    • pp.336-339
    • /
    • 2008
  • Monthly mean data of Angstrom exponent and Aerosol optical thickness (AOT) from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) measurements over the East Asian waters were analyzed. Increasing trend of the satellite-derived Angstrom exponent was found over 1998-2006 while AOT mean was observed stable during the same period. Statistical test showed that annual increase in Angstrom exponent of about 0.01 is statistically significant over three study sub-areas out of six surrounding waters of Japan. Comparison with Aqua/MODIS-derived Angstrom exponent time series over June 2002 through June 2008 showed consistent correlation, with similar statistical significance. The trend of Angstrom exponent was interpreted as increase in fraction of small aerosol particles to give quantitative estimates on the variability of aerosols. The mean increase is evaluated to be about +0.35%/yr or more in terms of the contribution of small particles to the total AOT, or sub-micron fraction (SMF).

  • PDF

시판 중인 우리밀 및 수입밀 밀가루의 품질 및 특성 비교 분석 (Comparison of Quality Analyses of Domestic and Imported Wheat Flour Products Marketed in Korea)

  • 김상숙;정혜영
    • 한국식품영양학회지
    • /
    • 제27권2호
    • /
    • pp.287-293
    • /
    • 2014
  • The physicochemical characteristics of 4 domestic wheat flour products were compared to those of 4 imported wheat flour products marketed in Korea. The contents of moisture, ash, protein, total dietary fiber (TDF), color (L, a, b), whiteness, solvent retention capacity (SRC), water absorption index (WAI), water soluble index (WSI), pasting characteristics by rapid visco analyzer (RVA), and principle component analysis (PCA) were analyzed. The domestic wheat flour products were composed of higher content in ash and protein, compared to the imported wheat flour products. The domestic wheat flour products had lower SRC and WSI characteristics than the imported wheat flour products. The values of lactic acid SRC (LASRC) in the imported wheat flour products showed an increasing trend as the protein content increased. The differences in viscosity were observed in the domestic wheat flour products. However, no major significant differences of viscosity were found among the imported wheat flour products. The result of PCA showed a consistent trend in the imported wheat flour (strong, medium, and weak), while a consistent trend was not shown in the domestic wheat flour products. Therefore, further research is needed to standardize the different types of domestic wheat flour products.