• Title/Summary/Keyword: relative comparison

Search Result 1,776, Processing Time 0.029 seconds

A study on the characteristics of environmental factors of granite dome models with different envelope structures in winter (외피 유형별 석재 모형돔의 동절기 환경 특성에 관한 연구)

  • 공성훈
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.11 no.5
    • /
    • pp.642-646
    • /
    • 1999
  • Factors governing the rate of heat exchange comprise the air temperature, the speed of air movement, relative humidity, and relation indoors. Recently, there are many researches on the transient analysis of indoor environmental factors such as the dry bulb temperature, relative humidity and air velocity in miniature models. The purpose of this study is to measure the environmental factors and to analyze and evaluate the characteristics of indoor environment with the different envelope structures using a granite dome model. According to the variation of humidity, the state of interior relative humidity for clay model has an equal tendency, although a little range of variation is shown in comparison to the cement model.

  • PDF

The Effect of Aquatic-Exercise on Skeletal Muscle Weight and Myofibrillar Protein Content of Rats with Steroids Injection (수중운동이 스테로이드를 투여한 흰쥐의 골격근 무게 및 단백질 함량에 미치는 효과)

  • Yoon Se-Won;Kim Tae-Youl;Choi Suk-Joo
    • The Journal of Korean Physical Therapy
    • /
    • v.15 no.3
    • /
    • pp.189-201
    • /
    • 2003
  • The purpose of this study was to know the effect of aquatic-exercise on muscle atrophy which induced by steroid injection. The forty-eight Sparague-Dawley adult male rats were assigned to the 4 groups; Group I (distilled water injection), Group II (steroid injection), Group III (distilled water injection with aquatic exercise), Group IV (steroid injection with aquatic exercise). We observed their body weight, muscle relative weight, myofibrillar protein content. The results of this study were as follows; 1. Body weight was decreased rapidly on steroid injection groups in comparison with distilled water injection groups after 2 weeks (p<0.01), but that was almost recovered as before test on steroid injection group with aquatic exercise. 2. The relative weight of gastrocnemius muscles was decreased on steroid injection groups in comparison with distilled water injection groups. however, Decrease of it on steroid injection group with aquatic exercise for steroid injection group was fallen. There was very significant difference after 4 weeks (p<0.01). 3. Myofibrillar protein content of gastrocnemius muscles was decreased on steroid injection groups in comparison with distilled water injection groups. however, Decrease of it on steroid injection group with aquatic exercise for steroid injection group was fallen. There was significant difference after 4 weeks (p<0.05).

  • PDF

A Comparative Study on Bayes Estimators for the Multivariate Normal Mcan

  • Kim, Dal-Ho;Lee, In suk;Kim, Hyun-Sook
    • Communications for Statistical Applications and Methods
    • /
    • v.6 no.2
    • /
    • pp.501-510
    • /
    • 1999
  • In this paper, we consider a comparable study on three Bayes procedures for the multivariate normal mean estimation problem. In specific we consider hierarchical Bayes empirical Bayes and robust Bayes estimators for the normal means. Then three procedures are compared in terms of the four comparison criteria(i.e. Average Relative Bias (ARB) Average Squared Relative Bias (ASRB) Average Absolute Bias(AAB) Average Squared Deviation (ASD) using the real data set.

  • PDF

AHP Analysis Model for drawing Importance Priorities of IT Service developments for Smart Tourism (스마트관광을 위한 IT서비스 개발의 우선순위 도출을 위한 AHP 분석모델)

  • Kim, Keun-Hyung
    • The Journal of Information Systems
    • /
    • v.28 no.4
    • /
    • pp.49-64
    • /
    • 2019
  • Purpose The purpose of this paper is to observe the relative priorities of importances among IT services for Smart tourism as well as the relative priorities of importances among ways for developing the IT Services. Design/methodology/approach AHP analysis model was designed with 3 layers in order to recognize the relative importances priorities of IT services and the ways developing the IT services in Smart tourism. The factors in the top layer consist of Pre-trip IT services, During-trip IT services and Post-trip IT services. The lower factors in second layer of the Pre-trip IT services consists of Tourism information search, Online reservation and Price comparison. The lower factors of the During-trip IT services consists of Context recognition, Virtual Reality and Drone Application. The lower factors of the Post-trip IT services consists of Interactive Sharing and Tagging. The factor of third layer, the ways of developing the IT services consist of Company leading, University leading and Industry-University Collaboration. The structural questionnaire based on the AHP analysis model was designed and used to survey experts in IT and tourism areas. The collected data by the question investigation was analyzed by AHP analysis technique. Findings The importance priority of During-trip IT service was highest among in the three type IT services of tourism life cycle. The importance priority of Price comparison service was highest among IT services for Pre-trip. The importance priority of the Context recognition service was highest among IT services for During-trip. The Interactive sharing service was highest among IT services for Post-trip. It would be confirmed for the IT service development ways of Company leading to be suitable for most of the It services, such as Tourism information search, Online reservation, Price comparison, Context recognition, Virtual reality, Drone application, Interactive sharing.

An Analysis of the Relative Efficiency for the National University Libraries using DEA Model (DEA를 이용한 국립대학도서관 경영효율성 분석)

  • Jo, Sung-Han;Park, Tong-Jin;Lee, Gil-Ho;Yoon, Dong-Won
    • Journal of Korean Library and Information Science Society
    • /
    • v.40 no.1
    • /
    • pp.253-274
    • /
    • 2009
  • Data Envelopment Analysis(DEA) model is a linear programing based technique for measuring the relative performance of organizational units where the presence of multiple inputs and outputs makes comparison difficult. DEA model allows each unit to adopt a set of weight that shows it in the most favorable light in comparison to the other units. The purpose of this study was to evaluate the performance of the libraries of national university in terms of relative efficiency, measured by the method of DEA. Twenty six libraries of national universities in Korea were used to analyze. The number of employees, size of library, budget, and number of books were used for input data, and the number of visitors, number of loan books, and number of books for lending and borrowing were used for output data. We found out that number of libraries with 100% relative efficiency among 26 libraries from 2005 to 2007 were only 9, 9 and 10, respectively. Moreover most of the libraries need to increase outputs and decrease inputs in order to improve efficiency.

  • PDF

A Comparison of Surge Behaviors in Multi-Stage and Single-Stage Axial Flow Compressors

  • Yamaguchi, Nobuyuki
    • International Journal of Fluid Machinery and Systems
    • /
    • v.9 no.4
    • /
    • pp.338-353
    • /
    • 2016
  • Information on the surge behaviors and stall stagnation boundaries for a nine-stage axial flow compressor are summarized on the basis of analytical data in comparison with those for a single-stage one, with attention to the pressure ratio effect. The general trends of the surge loop behaviors of the pressure-mass flow are similar for both compressors including the fact that the subharmonic surges tend to appear very near the stall stagnation boundaries. With respect to the nine-stage compressor, however, the mild loops in the subharmonic surges tend to be very small in size relative to the deep loops, and at the same time, insufficient surge recovery phenomenon, which is a kind of subharmonic surge, appears also far from the stagnation boundary for relatively short delivery flow-paths. The latter is found to be a rear-stage surge caused by unstalling and re-stalling of the rear stages with the front-stages kept in stall in the stalled condition of the whole compressor, which situation is caused by stage-wise mismatching in the bottom pressure levels of the in-stall multi-stage compressor. The fundamental information on the stall stagnation boundaries is given by a group of normalized geometrical parameters including relative delivery flow-path length, relative suction flow-path length, and sectional area-pressure ratio, and by another group of normalized frequency parameters including relative surge frequencies, modified reduced resonance frequencies, and modified reduced surge frequencies. Respective groups of the normalized parameters show very similar tendency of behaviors for the nine-stage compressor and the single-stage compressor. The modified reduced resonance frequency could be the more reasonable parameter suggesting the flow-induced oscillation nature of the surge phenomena. It could give the stall stagnation boundary in a more unified manner than the Greitzer's B parameter.

A comparison study on the estimation of the relative risk for the unemployed rate in small area (소지역의 실업률에 대한 상대위험도의 추정에 관한 비교연구)

  • Park, Jong-Tae
    • Journal of the Korean Data and Information Science Society
    • /
    • v.20 no.2
    • /
    • pp.349-356
    • /
    • 2009
  • In this study, we suggest the estimation method of the relative risk for the unemployment statistics of a small area such as si, gun, gu in Korea. The considered method are the usual pooled estimator, weighted estimator with the inverse of log-variance as weights, and the Jackknife estimator. And we compare with the efficiency of the three estimators by estimating the bias and mean square errors using real data from the 2002 Economically Active Population Survey of Gyeonggi-do. We compute the unemployed rate of male and female in small areas, and then estimate the common relative risk for the unemployed rate between male and female. Also, the stability and reliability of the three estimators for the common relative risk was evaluated using the RB(relative bias) and the RRMSE(relative root mean square error) of these estimators. Finally, the Jackknife estimator turned out to be much more efficient than the other estimators.

  • PDF

The Effect of Media Richness, Social Presence, and Life Satisfaction on Continuance Usage Intention or Withdrawal Intention of SNS Users via Relative Deprivation (매체 풍요도, 사회적 존재감 및 생활 만족도가 상대적 박탈감을 통해 SNS 이용자의 이용 지속 의도 또는 이탈 의도에 미치는 영향)

  • Lee, Un-Kon
    • Journal of Distribution Science
    • /
    • v.14 no.10
    • /
    • pp.165-178
    • /
    • 2016
  • Purpose - This study aims to empirically verify the impact of media richness, social presence, and prior life satisfaction on various continual usage or withdrawal behaviors of SNS users via both a positive path of satisfaction and a negative path of relative deprivation. By identifying these causal paths, we observe dynamic interactions of SNS user psychology in a balanced view, and provide some implications about design principles for SNS providers. Research design, data, and methodology - We developed 16 hypothesis based on media richness theory, social presence theory, social comparison theory, the literature about relative deprivation, and the literature about the various reactions of IS users. The rich SNS media, social presence recognition among peer SNS users, and prior life satisfaction could generate positive experience, attitude, and virtuous behavioral intentions among SNS users. At the same time, rich media, low social presence, and low prior life satisfaction could generate relative deprivation and could increase withdrawal behavioral intentions such as refusal to provide information, misrepresentation of information, and removal of uploaded information in SNS. Scenario surveys were conducted to collect data from potential SNS users. Data from 357 surveys were collected and analyzed through a PLS algorithm to test the hypotheses. Results - Media richness, social presence, and prior life satisfaction could significantly increase perceived enjoyment, satisfaction, and behavioral intention of continual usage and knowledge sharing. They also could significantly decrease refusal and misrepresentation intention. Relative deprivation is significantly decreased only by prior life satisfaction. Relative deprivation could not significantly decrease satisfaction, but it could significantly increase misrepresentation and removal intention, which could be regarded as information distortion intention. Conclusions - SNS providers should focus on developing rich media and social presence support because these two variables could impact the positive experiences of SNS users. Moreover, the positive experiences could heavily influence SNS user behavior. Some management is needed to prevent relative deprivation and its consequences of misrepresentation and removal intention. SNS providers should prevent SNS users from excessive image misrepresentation and removal as this information distortion could be the source of relative deprivation.