• International Journal of Highway Engineering
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• v.9 no.3
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• pp.1-12
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• 2007

Roads in Korea can be classified into four types according to their responsible authorities. For example, Motorway is constructed, managed, and operated by the Korea Highway Corporation. Ministry of Construction and Transportation is in charge of National Highway, and Province Roads are run by each province government. Urban/county Roads are run by corresponding local government. This study analyses the trends of road accidents for each road type. For this purpose, the numbers of accidents, fatalities, and injuries are compared for each road type for last 15 years. The result shows that Urban/County Roads are the most dangerous, while Motorways are the safest, when we simply compare the numbers of accidents, fatalities, and injuries. However, when we compare these numbers by dividing by total road length, National Highway becomes the most dangerous while Province Roads becomes the safest. In the case of road accidents, fatalities, and injuries per vehicle km, which is known as the most objective comparison measure, it turns out that National Highway is the most dangerous roads again. This study also developed time series models to estimate trends of fatalities for each road type. These models will be useful when we set up or evaluate targets of national road safety.

• Journal of Animal Science and Technology
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• v.46 no.1
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• pp.31-38
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• 2004

Data from five Hanwoo breeding farms were collected to analyze the effects of parity, season, nutrition and reproduction on body conditions of heifers and cows and to analyze the relationships of body conditions with reproductive performances and body growth. Analytic models included farms and parity which were run through SAS to estimate least squares means and correlation coeflicients between traits body condition scores(BCS) of I(very emaciated) through 9(very obese) scale at service and at calving. calving interval, days to rebreeding, gestation length. number of services per conception. Overall averages were 4.55 for BCS at service, 5.42 for BCS at calving. 406.7days of calving interval, 287.7days of gestation length, 66.2days from calving 10 first service and 1.78 times of services per conception. Number of services per conception was 1.50${\sim}$1.74 times for the cows of BCS 5 or under and 2.00${\sim}$3.00 for those of BCS 6 or higher. Body weight of calves from cows observed averaged 23.3kg at birth and 70.7kg at weaning. 57 percent of cows showed BCS 4${\sim}$5 at service while 46 percent of those showed 5${\sim}$6 at calving. Estimated phenotypic correlation coefficients of BCS at service with BCS at calving, calving interval, gestation length, number of services per conception were low but positive: 0.16, 0.26. 0.08 and 0.06. respectively. Phenotypic correlations of BCS at calving with calving interval, gestation length and number of services per conception were estimated to be also low and positive: 0.10, 0.13 and 0.10. respectively. However, phenotypic correlations between calving interval and gestation length, and between gestation length and number of services per conception were negative but low as - 0.11 and- 0.13 each.

• Journal of Korea Water Resources Association
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• v.45 no.4
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• pp.409-418
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• 2012

A modified standardized precipitation index was developed by considering the length of dry period and surface run-off effect. The official reports and newspapers on drought from 1973 to 2009 were quantified to evaluate drought indices. The developed index was evaluated using the receiver operating characteristic analysis. In order to suggest improved drought index, we cut the precipitation amount that may do not contribute the mitigation of drought and weight dry period by considering cumulative distribution, decile distribution of dry periods. Drought detection capability of the suggested index has improved by weighting of dry period effects and considering precipitation amounts contributing drought mitigation.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.10-17
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• 2016

Control Chart is a graph which dots the characteristic values of a process. It is the tool of statistical technique to keep a process in controlled condition. It is also used for investigating the state of a process. Therefore many companies have used Control Chart as the tool of statistical process control (SPC). Products from a production process represent accidental dispersion values around a certain reference value. Fluctuations cause of quality dispersion is classified as a chance cause and a assignable cause. Chance cause refers unmanageable practical cause such as operator proficiency differences, differences in work environment, etc. Assignable cause refers manageable cause which is possible to take actions to remove such as operator inattention, error of production equipment, etc. Traditionally ${\bar{x}}-R$ control chart or ${\bar{x}}-s$ control chart is used to find and remove the error cause. Traditional control chart is to determine whether the measured data are in control or not, and lets us to take action. On the other hand, RNELCC (Reflected Normal Expected Loss Control Chart) is a control chart which, even in controlled state, indicates the information of economic loss if a product is in inconsistent state with process target value. However, contaminated process can cause control line sensitive and cause problems with the detection capabilities of chart. Many studies on robust estimation using trimmed parameters have been conducted. We suggest robust RNELCC which used the idea of trimmed parameters with RNEL control chart. And we demonstrate effectiveness of new control chart by comparing with ARL value among traditional control chart, RNELCC and robust RNELCC.

• Journal of Veterinary Clinics
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• v.8 no.1
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• pp.31-45
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• 1991

Present experiment was performed in order to establish the optimal reaction conditions for determination of urinary AAP and GRS activities and to investigate the applicability of urinary AAP and GRS in nephrotoxicity test in rat. The results were as follows ; 1. The optimal pH of phosphate buffer for determination of urinary AAP activity was 7.8. 2. The Michaelis constant of urinary AAP ranged from 0.8 to 1.0mmol/$\ell$ 3. The optimal wave length for determination of urinary GRS activity was 405nm. 4. The optimal pH of acetate buffer for determination of urinary GRS activity was 5.6. 5. The Michaelis constant of urinary GRS ranged from 0.65~0.79mmo1/$\ell$. 6. The AAP activities in gel-filtered samples were significantly higher than those in crude samples. Mean values of AAP activities in gel-filtered samples and crude samples were 29$\pm$20 and 20$\pm$13U/$\ell$, respectively. 7. There was not significant difference between gel-filtered samples and crude samples in urinary GRS activities. Mean values of GRS activities in gel-filtered samples and crude samples were 57$\pm$40 and 56$\pm$39U/$\ell$, respectively. 8. Limits of linearity of urinary AAP and GRS activities were 2.0 and 3.6U/$\ell$, respectively. 9. Within-run imprecisions of the assays, were acceptable, as the coefficients of the AAP activities ranged from 5.5 to 6.3% and those of GRS activities ranged from 1.4 to 6.2%, respectively. 10. Urinary AAP excretion was 675$\pm$227mu/24hrs.kg before administration of potassium dichromate, and increased significantly to 4246$\pm$2567mU/24hrs.kg within 24 hours after administration of potassium dichromate. 11. Urinary GRS excretion did not increase significantly after administration of potassim dichromate. 12. From these findings it is concluded that urinary AAP excretion is early and sensitive Indicator to detect kidney damage in nephrotoxicity experiment.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.71-80
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• 2011

The fish fauna and characteristics of population of Zacco platypus in the 9 microhabitat at the Tan Stream was investigated from August, 2009 to April, 2010. The collected species during the survey period were 17 species belong to 7 families. Korea endemic species were Hemiculter eigenmanni and Odontobutis interrupta, which showed a ration of 11.8% in collected species. Dominant species was Z. platypus and subdominant species was Carassius auratus. Dominated species of C. auratus was at the dam-type pool, Meander-type pool, run, and rock-type pool, Pseudogobio esocinus was side channel, Rhinogobius brunneus was riffle, and Z. platypus was channel connected pool, substrate-type pool and channel unconnected pool. Length-weight relationship in the population of Z. platypus was 3.29. PCA analysis was in to the 3 groups identified. Bary-curtis cluster analysis indicated that the substrate-type pool and channel unconnected pool 65.9% showed the most similar, riffle, and dam-type 30.4% were identified as the most contrast.

• Journal of Korean Neurosurgical Society
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• v.53 no.2
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• pp.65-71
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• 2013

Objective : In order to develop a novel nerve guidance channel using porcine small intestinal submucosa (SIS) for nerve regeneration, we investigated the possibility of SIS, a tissue consisting of acellular collagen material without cellular immunogenicity, and containing many kinds of growth factors, as a natural material with a new bioactive functionality. Methods : Left sciatic nerves were cut 5 mm in length, in 14 Sprague-Dawley rats. Grafts between the cut nerve ends were performed with a silicone tube (Silicon group, n=7) and rolled porcine SIS (SIS group, n=7). All rats underwent a motor function test and an electromyography (EMG) study on 4 and 10 weeks after grafting. After last EMG studies, the grafts, including proximal and distal nerve segments, were retrieved for histological analysis. Results : Foot ulcers, due to hypesthesia, were fewer in SIS group than in Silicon group. The run time tests for motor function study were 2.67 seconds in Silicon group and 5.92 seconds in SIS group. Rats in SIS group showed a better EMG response for distal motor latency and amplitude than in Silicon group. Histologically, all grafts contained some axons and myelination. However, the number of axons and the degree of myelination were significantly higher in SIS group than Silicon group. Conclusion : These results show that the porcine SIS was an excellent option as a natural biomaterial for peripheral nerve regeneration since this material contains many kinds of nerve growth factors. Furthermore, it could be used as a biocompatible barrier covering neural tissue.

• Quality Improvement in Health Care
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• v.6 no.1_2
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• pp.136-149
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• 1999

Background : Although a number of studies are related to QA improvement, there are few studies applied various method of QA tools. This study reviewed the availability of general quality assurance(QA) tools according to ten steps in performing quality improvement activities at emergency room of a tertiary teaching hospital which has more than 1,000 beds. Methods : All patients in emergency room from 15th Oct. 1997 to 5th Sep. 1998 were surveyed. The survey data based on the patient's records of emergency room were evaluated according to length of stay, and we tried to identify problems with management of emergency room. To solve the problems, our team applied general QA tools(brainstorming, flow chart, nominal group technique, benchmarking, cause-and-effect diagram, run chart, control chart) to quality improvement activities and discussed the availability of the tools. Results : After the activities such as changes of staffing, the establishment of local area network and chest pain clinic, application of triage and so on, the percentage of patient who had stayed more than six hours was reduced from 56.0% to 46.8%. The mean number of patients per day in emergency room was increased from 49 to 62. But the reporting time for laboratory test was not changed after these activities. Conclusion : Each QA tool has unique benefit and limitation, but we can implement and evaluate the quality improvement activities more scientifically and systematically by applying these tools to practice according to QA ten steps.

• Journal of KIISE
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• v.44 no.8
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• pp.760-766
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• 2017

Repetitive strings have been studied in diverse fields such as data compression, bioinformatics and so on. Recently, two problems of approximate periods of strings over integer alphabets were introduced, finding minimum ${\delta}-approximate$ periods and finding minimum ${\gamma}-approximate$ periods. Both problems can be solved in $O(n^2)$ time when n is the length of the string. In this paper, we present two parallel algorithms for solving the above two problems in O(n) time using $O(n^2)$ threads, respectively. The experimental results show that our parallel algorithms for finding minimum ${\delta}-approximate$ (resp. ${\gamma}-approximate$) periods run approximately 19.7 (resp. 40.08) times faster than the sequential algorithms when n = 10,000.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.4
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• pp.145-152
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• 2008

The initial wave lengths of tsunamis can be several tens to hundreds kilometers. Thus, the importance of the frequency dispersive effects in proportion to variation of the wave length, and should be properly considered in numerical simulation of tsunami propagation for a better accuracy. Recently, a practical dispersion-correction scheme has been developed by adding dispersion-correction terms(Cho et al., 2007). The new model employing the numerical technique has been verified by comparing numerical results with available analytic solutions, however, the new model has not yet been applied on a real topography. In this study, the new model is applied on a real topography and its applicability is examined. To study the applicability of the new model, two historical tsunami events are simulated for Sokcho, Mukho and Pohang harbors, with the tide gage records. Numerical results, the arrival time and the maximum water level at the tidal stations, are compared with observed data at each harbor.