• Title/Summary/Keyword: Reliability Value

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A Study on Utilization and Perceived Service Quality of the University Foodservice (대학급식 이용실태 및 급식서비스 품질이 고객만족과 고객태도에 미치는 영향)

  • Jung, Hyun-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.4
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    • pp.633-643
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    • 2013
  • This study investigated the efficiency of university foodservice operations by analyzing the effect of consumer's perception towards university foodservice quality. University students in the Jeonnam area were surveyed and 571 out of 700 surveys were chosen (response rate: 97.0%). SPSS (ver. 20.0) was used to conduct descriptive analysis, factor analysis, reliability analysis, t-test, and multiple regression analysis. The results show that 21.9% of university students have never used the university foodservice, while 48.7% of university students have eaten there 1~2 times per week. The most common reasons reported for avoiding the university foodservice were a limited menu selection (51.5%) and an untasty food (45.8%). The perception of overall service quality at the university foodservice scored relatively low (3.01 points), compared with its importance (3.89 points). The food taste, menu variety, and quality of food ingredients are factors that require improvement for operational strategies by the importance-performance analysis (IPA). The food factors (taste, variety, and quality) among university foodservice qualities had a significantly positive effect on consumers' overall satisfaction (p<0.001), perceived value (p<0.01), intent to recommend (p<0.001), and intent to revisit (p<0.01). These result indicate that the university foodservice management should focus on developing food factors and strive to meet the needs of university students through continuous customer surveys.

Empirical Research on the R&D Investment and Performance of Venture Businesses (벤처기업의 R&D 투자와 성과에 관한 실증연구)

  • Lee, D.K.;Lee, C.K.;Kim, J.H.
    • 한국벤처창업학회:학술대회논문집
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    • 2008.04a
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    • pp.179-208
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    • 2008
  • In this research, an empirical analysis was performed to determine the correlation between management performance and R&D investment for domestic venture businesses in each industry. Specifically, an empirical analysis for each industry was attempted not only to clarify the general hypothesis on the relationship between management performance and R&D investment for venture businesses but also to demonstrate that differences exist for each industry. Empirical analysis was conducted for eight industries with respect to the $2002{\sim}2006$ panel data extracted as investigative results from the "Investigation Report on Science and Technology R&D Activities" published by the Ministry of Science and Technology. Industrial classification was limited to the middle-level classification (2-digit) in the Korea Standard Industry Code (KSIC) owing to the limited number of panels. Although this research only verified the overall positive effect of R&D activities and funds for existing research on corporate value or productivity and management performance, it was able to document the difference for each individual industry and each business size unlike existing research.Furthermore, the reliability of the research results was enhanced by targeting companies that have been continuously conducting R&D and management activities using consistent 5-year panel data in the analysis. Again, this was something that existing research did not have. Finally, through the use of recent data from 2002 after the IMF economic crisis up to 2006 in the empirical analysis, this research proposed the problems due to the prevailing circumstances at the time of entering the advanced nation stage based on an empirical analysis; the prevailing problems during the pursuit of advanced nation status before the IMF crisis broke out were not tackled. The key empirical analysis yielded several results. First, capital and size of the labor force have a positive correlation with the management performance for the entire company or the venture business. This applies to all eight industries as the subjects of the analysis. Second, although the number of years since a company has been established can have positive or negative correlation with management performance for the entire company or venture business in specific industries, a definite overall trend cannot be identified. Third, R&D investment can be said to have an overall positive effect on corporate management performance. Fourth, the size of the research staff cannot be said to be a factor unilaterally affecting the management performance of the entire company or the venture business. Fifth, the number of years a research institute has been in operation, which was assumed to have a positive effect on the management performance of a company because of the accumulated R&D know-how -- definitely acts as a positive factor contributing to the management performance of a company.

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Development of Bicycle Accident Prediction Model and Suggestion of Countermeasures on Bicycle Accidents (자전거 사고예측모형 개발 및 개선방안 제시에 관한 연구)

  • Kwon, Sung-Dae;Kim, Yoon-Mi;Kim, Jae-Gon;Ha, Tae-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.5
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    • pp.1135-1146
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    • 2015
  • This thesis aims to improve the safety of bicycle traffic for activating the use of bicycle, main means of non-powered and non-carbon transportation in order to cope with worldwide crisis such as climate change and energy depletion and to implement sustainable traffic system. In this regard, I analyzed the problem of bicycle roads currently installed and operated, and developed the bicycle accident forecasting model. Following are the processes for this. First, this study presented the current status of bicycle road in Korea as well as accident data, collect the data on bicycle traffic accidents generated throughout the country for recent 3 years (2009~2011) and analyzed the features of bicycle traffic accidents based on the data. Second, this study selected the variable affecting the number of bicycle accidents through accident feature analysis of bicycle accidents at Jeollanam-do, and developed accident forecast model using the multiple regression analysis of 'SPSS Statistics 21'. At this time, the number of accidents due to extension per road types (crossing, crosswalk, other single road) was used. To verify the accident forecast model deduced, this study used the data on bicycle accident generated in Gwangju, 2011, and compared the prediction value with actual number of accidents. As a result, it was found out that reliability of accident forecast model was secured through reconciling with actual number of cases except certain data. Third, this study carried out field survey on the bicycle road as well as questionnaire on satisfaction of bicycle road and use of bicycle for analysis of bicycle road problems, and presented safety improvement measures for the problems deduced as well as bicycle activation plans. This study is considered to serve as the fundamental data for planning and reorganizing of bicycle road in the future, and expected to improve safety of bicycle users and to promote activation of bicycle use as the means of transportation.

The Closure Stage of Cranial Sutures in Correlation with Age (증령적 변화로서의 두개골 봉합의 유합 상태)

  • Ahn, Hyoung-Joon;Sin, Kyoung-Jin;Kwon, Jeong-Seung;Do, Hyung-Joo;Choi, Jong-Hoon;Kim, Chong-Youl
    • Journal of Oral Medicine and Pain
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    • v.26 no.4
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    • pp.377-393
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    • 2001
  • In order to study the closure stage of cranial sutures and its correlations with age, the ectocranial closure stage of coronal suture, sagittal suture, and lambdoidal suture of 67 skulls was measured. Among the skulls kept at the department of anatomy, college of medicine, Yonsei University, the ones with ages identified were used for this study. These measurements of suture closure were conducted by 4 examiners independently. The sutures were further divided by Frederic's method into 16 suture parts. The closure stages were classified by five stages of Broca-Ribbe. The following results were obtained: 1. The inter-observer reliability among 4 examiners showed high intraclass correlation coefficient of over 0.75(mean : 0.856) in all suture parts. Therefore, the determination of closure stage wasn't influenced by the subjective view of each examiner. 2. In all suture parts, the closure stage increased proportionally with age.(p<0.01) In terms of each suture part, the S2 part of sagittal suture showed the highest correlation(68.1%) while the L1-R part of lambdoidal suture showed the lowest correlation(51.3%). In addition, in terms of suture types, the correlation with age decreased in the order of sagittal suture(60.0%), coronal suture(57.7%), and lambdoidal suture (55.7%). In general, the average value of suture closure stages had 57.8% correlation with age(p<0.01). 3. The most frequent suture closure stage according to age group was '0' for ages below 30, '0' and '1' for ages within the 30's, '1' and '2' for ages within the 40's, and '2' for ages within the 50's. With older age groups, the frequency of '3' and '4' increased, and the suture closure stage increased proportionally with age. 4. The mean age by closure stage of each suture were within the 40's for the closure stage of '1', within the 50's for the closure stage of '2', and from 50's through 60's for the closure stage of '3'. The standard deviation was over 10 for all closure stages. In addition, at the same suture closure stage, the mean age according to the coronal suture was higher than the ages according to the sagittal suture or lambdoidal suture. Especially, C1-R, C1-L, C2-R, and C2-L parts showed the highest age when at the same suture closure stage. 5. The values appropriate for age estimations using suture closure stages of 16 suture parts were calculated, and a calculator for age estimation ($R^2=0.6944$, p<0.01) by ectocranial suture closure stage for Koreans is presented. From the above results, the method of using the closure stage of sutures of the skull to estimate age can be useful in individual identification of forensic science. Further extensive and accurate research using larger samples would be worthy of study.

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A Comparative Study on Image Quality of Breast Image Tests using ACR Phantom (ACR 팬텀을 이용한 시스템별 유방검사 영상의 비교 연구)

  • Hong, Dong-Hee;Jung, Hong-Ryang;Lim, Cheong-Hwan
    • Journal of radiological science and technology
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    • v.29 no.4
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    • pp.241-247
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    • 2006
  • Recently, interests and utilization on Computed Radiography(CR) and Digital Radiography(DR) tends to increase owing to an introduction of Picture Archiving and Communication System(PACS) and an accuracy control of special medical equipment for a breast imaging examination. This study was intended to compare and analyze a detector's imaging quality by each system to be used for the breast imaging examination by using ACR Phantom used at the accuracy control. As an evaluation method, a significance and reliability of image's value using the ACR Phantom was analyzed by using SPSS program. The results are followed. 1. For the fiber, there was 3.9 score in Screen-Film, 4.2 score in CR($50{\mu}m$), 3.2 score in CR($100{\mu}m$), and 4.2 score in DR. There was the high score in the order of CR($50{\mu}m$), DR, Screen-Film, and CR($100{\mu}m$)(P<0.05). 2. For the calcification, there was 2.7 score in Screen-Film, 2.5 score in CR($50{\mu}m$), 2.0 score in CR($100{\mu}m$), and 2.9 score in DR. There was the high score in the order of DR, Screen-Film, CR($50{\mu}m$), and CR($100{\mu}m$).(0.025(P<0.05). 3. For Mass, there was 3.8 score in Screen-Film, 3.8 score in CR($50{\mu}m$), 3.6 score in CR($100{\mu}m$), and 4.5 score in DR. There was the high score in the order of DR, CR($50{\mu}m$), Screen-Film, and CR($100{\mu}m$) (P<0.1). 4. As the total score, there was 10.4 score in Screen-Film, 10.6 score in CR($50{\mu}m$), 8.7 score in CR($100{\mu}m$), and 11.3 score in DR. There was the high score in the order of DR, $CR(50{\mu}m$), Screen-Film, and $CR(100{\mu}m$). As shown in the above results, it can be known that DR and Screen-Film System has higher image quality than CR. But, DR has unstability caused by element, and Screen-Film has the low image quality caused by artifact as disadvantages. When Dual-Side CR($50{\mu}m$) was used among CR systems which had the problem of low image quality, it was indicated that there was no difference with Screen-Film System. Because the radiation imaging examination tends to become digitalized, each system for the breast imaging examination will need to be developed and supplemented.

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The Effect of Information Service Quality on Customer Loyalty: A Customer Relationship Management Perspective (정보서비스품질이 고객로열티에 미치는 영향에 관한 연구: 고객관계관리 관점)

  • Kim, Hyung-Su;Gim, Seung-Ha;Kim, Young-Gul
    • Asia pacific journal of information systems
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    • v.18 no.1
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    • pp.1-23
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    • 2008
  • As managing customer relationship gets more important, companies are strengthening information service using multi-channels to their customers as a part of their customer relationship management (CRM) initiatives. It means companies are now accepting such information services not as simple information -delivering tools, but as strategic initiatives for acquiring and maintaining customer loyalty. In this paper, we attempt to validate whether or not such various information services would impact on organizational performance in terms of CRM strategy. More specifically, our research objective is to answer the next three questions: first, how to construct the instruments to measure not information quality but information service quality?; second, which attributes of information service quality can influence corporate image and customer loyalty?; finally, does each information service type have unique characteristics compared with others in terms of influencing corporate image and customer loyalty? With respect to providing answers to those questions, the previous studies had been limited in that those studies failed to consider the variety of types of information service or restricted the quality of information service to information quality. An appropriate research model answering the above questions should consider the fact that most companies are utilizing multi channels for their information services, and include the recent strategic information service such as customer online community. Moreover, since corporate information service could be regarded as a type of products or services delivered to customer, it is necessary to adopt the criteria for assessing customer's perceived value when to measure the quality of information service. Therefore, considering both multi-channels and multi-traits may enable us to tell the detailed causal routes showing which quality attributes of which information service would affect corporate image and customer loyalty. As information service channels, we include not only homepage and DM (direct mail), which are the most frequently applied information service channels, but also online community, which is getting more strategic importance in recent years. With respect to information service quality, we abstract information quality, convenience of information service, and timeliness of information service through a wide range of relevant literature reviews. As our dependant variables, we consider corporate image and customer loyalty that both of them are the critical determinants of organizational performance, and also attempt to grasp the relationship between the two constructs. We conducted a huge online survey at the homepage of one of representative dairy companies in Korea, and gathered 367 valid samples from 407 customers. The reliability and validity of our measurements were tested by using Cronbach's alpha coefficient and principal factor analysis respectively, and seven hypotheses were tested through performing correlation test and multiple regression analysis. The results from data analysis demonstrated that timeliness and convenience of homepage have positive effects on both corporate image and customer loyalty. In terms of DM, its' information quality was represented to influence both corporate image and customer loyalty, but we found its' convenience have a positive effect only on corporate image. With respect to online community, we found its timeliness contribute significantly both to corporate image and customer loyalty. Finally, as we expected, corporate image was revealed to provide a great influence to customer loyalty. This paper provides several academic and practical implications. Firstly, we think our research reinforces CRM literatures by developing the instruments for measuring information service quality. The previous relevant studies have mainly depended on the measurements of information quality or service quality which were developed independently. Secondly, the fact that we conducted our research in a real situation may enable academics and practitioners to understand the effects of information services more clearly. Finally, since our study involved three different types of information service which are most frequently applied in recent years, the results from our study might provide operational guidelines to the companies that are delivering their customers information by multi-channel. In other words, since we found that, in terms of customer loyalty, the key areas would be different from each other according to the types of information services, our analysis would help to make decisions such as selecting strengthening points or allocating resources by information service channels.

ROC Analysis of Visual Assessments Made in Gated Blood Pool Scans of Patients with Coronary Artery Disease (관상동맥질환에서 심장풀 스캔의 육안적 평가에 대한 ROC 분석)

  • Lee, Kyun-Han;Choi, Yoon-Ho;Lee, Bum-Woo;Moon, Dae-Hyuk;Koong, Sung-Soo;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.23 no.2
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    • pp.175-181
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    • 1989
  • Visual assessment of regional wall motion abnormality (RWMA) by gated blood pol scan (GBPS) serves as an useful parameter in the diagnosis, functional evaluation, and follow up in various clinical settings, but are still subject to some inherent limitations. On important problem may be the interobserver as well as intraobsever variation that may well be present due to the subjective nature of the interpretations. This study was carried out to determine the reliability and reproducibility of visual assessments made in GBPSs, and to observe the degree to which the results would be influenced by observer variation. Fifty two patients with coronary heart disease had resting GBPS and contrast ventriculography within 4 days appall. Contrast ventriculography-showed normal wall motion in 6 patients and the remaining 46 had RWMA in one or more segments. The anterior and left anterolateral views of all 52 GBPSs were analyzed by three independent observers, who selected from 5 scales, their level of confidence that there was RWMA in that segment. Reciever operating characteristic (ROC) curves for each analysis was plotted and the area under the curve $(\theta)$ was used as a parameter representing each observer's performance in his interpretations. The findings of contrast ventriculographies were used as the standard for RWMA. The apical and inferoapical segments showed the best correlation with contrast ventriculography ($\theta=0.90-0.94$, 0.81-0.94, respectively), and the inferior wall showed the poorest correlation $(\theta=0.70-0.74)$. The interpretations of the inferior, septal, apical, and posteroinferior, segments showed no difference between the observers, but there was significantly better performance in assessment by observer A compared to that by B or C for the anterolateral segments ($\theta=0.87$, 0.78, 0.76, respectively. p<0.01 for A vs B, p<0.05 for A vs C), as well as when all segments were considered altogether ($\theta=0.88$, 0.83, 0.82, respectively. both p<0.05). This was also true for the infero-apical segment between A and C ($\theta=0.09$, 0.81, p<0.05). The intraobserver variation, however, did not appear significant, with only the inferior segment for observer B showing any significant difference when observer A and B repeated the analysis 10 days latter. There was no difference in assessing dyskinesia, with all observers showing a high performance ($\theta=0.98$, 0.87, 0.97, respectively). The visual assessment of left ventricular ejection fraction by all three observers correlated well with the calculated value from a semiautomated method (Spearman's r = 0.91, 0.83, 0.83. p<0.01, p<0.05, p < 0.05). The assessment of LV and RV size also correlated well between the three observers (Kendall's w = 0.80, 0.51, p<0.01 for both left and right ventricles). The above findings suggest that RWMA visually assessed by GBPS correlates well with that done by contrast ventriculography. And although the observer's experience or skill may influence the results in certain segments, visual analysis of GBPS may serve as a reliable and reproducible means for evaluating ventricular function.

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Features of sample concepts in the probability and statistics chapters of Korean mathematics textbooks of grades 1-12 (초.중.고등학교 확률과 통계 단원에 나타난 표본개념에 대한 분석)

  • Lee, Young-Ha;Shin, Sou-Yeong
    • Journal of Educational Research in Mathematics
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    • v.21 no.4
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    • pp.327-344
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    • 2011
  • This study is the first step for us toward improving high school students' capability of statistical inferences, such as obtaining and interpreting the confidence interval on the population mean that is currently learned in high school. We suggest 5 underlying concepts of 'discretion of contingency and inevitability', 'discretion of induction and deduction', 'likelihood principle', 'variability of a statistic' and 'statistical model', those are necessary to appreciate statistical inferences as a reliable arguing tools in spite of its occasional erroneous conclusions. We assume those 5 concepts above are to be gradually developing in their school periods and Korean mathematics textbooks of grades 1-12 were analyzed. Followings were found. For the right choice of solving methodology of the given problem, no elementary textbook but a few high school textbooks describe its difference between the contingent circumstance and the inevitable one. Formal definitions of population and sample are not introduced until high school grades, so that the developments of critical thoughts on the reliability of inductive reasoning could not be observed. On the contrary of it, strong emphasis lies on the calculation stuff of the sample data without any inference on the population prospective based upon the sample. Instead of the representative properties of a random sample, more emphasis lies on how to get a random sample. As a result of it, the fact that 'the random variability of the value of a statistic which is calculated from the sample ought to be inherited from the randomness of the sample' could neither be noticed nor be explained as well. No comparative descriptions on the statistical inferences against the mathematical(deductive) reasoning were found. Few explanations on the likelihood principle and its probabilistic applications in accordance with students' cognitive developmental growth were found. It was hard to find the explanation of a random variability of statistics and on the existence of its sampling distribution. It is worthwhile to explain it because, nevertheless obtaining the sampling distribution of a particular statistic, like a sample mean, is a very difficult job, mere noticing its existence may cause a drastic change of understanding in a statistical inference.

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Time Dependent Evaluation of Corrosion Free Life of Concrete Tunnel Structures Based on the Reliability Theory (해저 콘크리트 구조물의 신뢰성 이론에 의한 시간 의존적 내구수명 평가)

  • Pack, Seung Woo;Jung, Min Sun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.3
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    • pp.142-154
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    • 2011
  • This study predicted the probability of corrosion initiation of reinforced concrete tunnel boxes structures using the Monte Carlo Simulation. For the inner wall and outer wall in the tunnel boxes, exposed to airborne chloride ion and seawater directly respectively, statistical values of parameters like diffusion coefficient D, surface chloride content $C_s$, cover depth c, and the chloride threshold level $C_{lim}$ were examined from experiment or literature review. Their average values accounted for $3.77{\times}10^{-12}m^2/s$, 3.0% by weight of cement, 94.7mm and 45.5mm for outer wall and inner wall, respectively, and 0.69% by weight of cement for D, $C_s$, c, and $C_{lim}$, respectively. With these parametric values, the distribution of chloride contents at rebar with time and the probability of corrosion initiation of the tunnel boxes, inner wall and outer wall, was examined by considering time dependency of chloride transport. From the examination, the histogram of chloride contents at rebar is closer to a gamma distribution, and the mean value increases with time, while the coefficient of variance decreases with time. It was found that the probability of corrosion initiation and the time to corrosion were dependent on the time dependency of chloride transport. Time independent model predicted time to corrosion initiation of inner wall and outer wall as 8 and 12 years, respectively, while 178 and 283 years of time to corrosion was calculated by time dependent model for inner wall and outer wall, respectively. For time independent model, the probability of corrosion at 100 years of exposure for inner wall and outer wall was ranged 59.5 and 95.5%, respectively, while time dependent model indicated 2.9 and 0.2% of the probability corrosion, respectively. Finally, impact of $C_{lim}$, including values specified in current codes, on the probability of corrosion initiation and corrosion free life is discussed.

Calibration of Gauge Rainfall Considering Wind Effect (바람의 영향을 고려한 지상강우의 보정방법 연구)

  • Shin, Hyunseok;Noh, Huiseong;Kim, Yonsoo;Ly, Sidoeun;Kim, Duckhwan;Kim, Hungsoo
    • Journal of Wetlands Research
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    • v.16 no.1
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    • pp.19-32
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    • 2014
  • The purpose of this paper is to obtain reliable rainfall data for runoff simulation and other hydrological analysis by the calibration of gauge rainfall. The calibrated gauge rainfall could be close to the actual value with rainfall on the ground. In order to analyze the wind effect of ground rain gauge, we selected the rain gauge sites with and without a windshield and standard rain gauge data from Chupungryeong weather station installed by standard of WMO. Simple linear regression model and artificial neural networks were used for the calibration of rainfalls, and we verified the reliability of the calibrated rainfalls through the runoff analysis using $Vflo^{TM}$. Rainfall calibrated by linear regression is higher amount of rainfall in 5%~18% than actual rainfall, and the wind remarkably affects the rainfall amount in the range of wind speed of 1.6~3.3m/s. It is hard to apply the linear regression model over 5.5m/s wind speed, because there is an insufficient wind speed data over 5.5m/s and there are also some outliers. On the other hand, rainfall calibrated by neural networks is estimated lower rainfall amount in 10~20% than actual rainfall. The results of the statistical evaluations are that neural networks model is more suitable for relatively big standard deviation and average rainfall. However, the linear regression model shows more suitable for extreme values. For getting more reliable rainfall data, we may need to select the suitable model for rainfall calibration. We expect the reliable hydrologic analysis could be performed by applying the calibration method suggested in this research.