• Journal of the Society of Naval Architects of Korea
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• v.54 no.2
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• pp.83-89
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• 2017

Numerical simulations of ship resistance have been performed to compare spatial characteristics of Courant number when using structured and unstructured meshes. When Euler scheme was used for time integration, the structured mesh provided a more efficient calculation because the calculation time interval was larger than that of unstructured mesh. The automatic generation of very small meshes in the unstructured mesh was mainly responsible for the limitation of calculation time interval. When local time stepping Euler scheme was applied, however, the ship resistance of unstructured mesh showed a rapid convergence while a slow convergence of ship resistance in structured mesh was caused by the small time interval in bulbous bow.

• The Korean Journal of Emergency Medical Services
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• v.22 no.3
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• pp.177-187
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• 2018

Purpose: The purpose of the study was to investigate the causes of non-transport in 119 ambulance services and to describe the difference in response time according to the reason for non-transport. Methods: This study analyzed 42,415 non-transport cases out of 123,158 cases using prehospital care reports in a metropolitan city. The Kruskal-Wallis test and the Wilcoxon-Mann-Whitney test were used to 6,857 cases for which time was recorded. Results: Non-transportation in 20${\bigcirc}{\bigcirc}$ comprised 33.1% of all ambulance services. The reason for non-transport were other reasons (25.5%), cancellation (23.8%), and moving to other vehicles (21.7%). There were differences in ambulance service times according to the reasons for non-transport. The activation interval was the longest (2.68 minutes) in the absence of the patient, and the response interval was the shortest (4.96 minutes) among the cancelled case. The total interval was the shortest time (21.97 minutes) in the cancellation cases and the longest time among the death cases (32.23 minutes). Conclusion: It is important to suggest the direction of development of emergency services by identifying the reasons for non-transport by ambulance services and describing the response time according to the reason for non-transport.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.22-24
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• 2005

RFID 시스템은 전자태그를 상품에 부착하여 리더를 통해 태그를 인식함으로써 상품의 정보 및 위치정보를 추적할 수 있다. 태그 객체의 위치정보는 시간에 따라 궤적 정보가 누적되는 이동체와 유사한 특성을 가지지만 이동체의 위치와 달리 태그의 위치는 리더의 위치로 인식되며 위치보고가 리더의 인식영역 안에서만 이루어지므로 시간축에 평행한 interval의 형태를 나타난다. 태그가 리더의 인식영역에 들어와 나가지 않으면 궤적이 완성되지 않아 리더에 머물고 있는 태그의 궤적을 표현할 수 없으므로 질의 시 이러한 태그를 검색할 수 없다. 시공간 이동체 색인에서는 이러한 태그의 특성을 표현하기 힘들기 때문에 태그의 특성을 고려한 색인이 필요하게 되었다. TPIR-Tree(Time Parameterized Interval R-tree)는 시간 매개변수 간격으로 태그의 interval을 정의하여 리더안에 머무는 태그의 interval을 표현할 수 있다. 그러나 각 interval이 시공간적으로 연결되어 있지 않아 색인 상에서 태그의 궤적을 검색하는 것은 매우 높은 검색 비용을 가지는 단점이 있다. 이 논문에서는 태그 궤적 검색 시 TPIR-Tree의 높은 검색 비용문제를 해결한 $TPIR^{*}$-Tree를 제안한다. 제안된 $TPIR^{*}$-Tree는 색인에서 태그의 궤적 정보를 유지할 수 있도록 하기 위해서 시간적으로 연결되지 않은 각 interval을 연결하기 위한 기법을 제시하고 있다. 또한. interval을 색인에 삽입할 때 연결정보를 유지하기 위해 이전 interval을 효율적으로 검색할 수 있는 방법을 제시하고 있다.

• Water for future
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• v.27 no.4
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• pp.135-143
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• 1994

The purpose of this study was to improve the understanding of the characteristics of the daily urban water use. The city of Kwangju in Korea was selected as a study area. The population of Kwangju in the end of 1993 was more than one million and two hundred thousand peoples. The average of daily water use in 1993 was about three hundred and fifty thousand tons a day. The variation of the urban water demand trend with time for a day was studied. One day was devided into 12 divisions with a 2hour increment. The water use demand for the given time interval of a day was observed. The water use index was defind in percentage that indicates the ratio of the amount of water use for a time interval to the amount of water use for a day. The water use index was found to be useful to manage and to operate the water supply systems. In addition to this, the probability distribution of the water use demand for each time interval was tested using the K-S(Komogorov-Smirnov) method. The normal distribution type was found to be appropriate as the probability distribution type for the variation of water demand for the given time interval of a day.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.456-459
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• 2006

Effects of pork thickness (5 and 7 mm), heating temperature (190 and $220^{\circ}C$) and time (40-180 sec), and flipping interval (10 and 30 sec) during cooking against survival levels of general bacteria and pathogenic microorganisms in pork were investigated. Under same heating temperature and time, 10 sec interval of flipping was more effective in sterilizing bacteria than 30 sec interval. Bacteria was not detected in 5-mm thick pork cooked for 80 sec at $190^{\circ}C$ with 10 sec flipping interval, and 120 sec heating at $190^{\circ}C$ and 30 sec flipping interval. Bacteria were not detected in most 7-mm thick pork cooked for 100 sec at $190^{\circ}C$ with 10 sec flipping interval, and 180 sec heating at $190^{\circ}C$ and 30 sec interval. Bacteria were not detected in most 5- and 7-mm thick pork cooked for 80 sec at $220^{\circ}C$ with 10 sec flipping interval, and 120 sec heating with 30 sec interval.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.2
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• pp.247-268
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• 2011

Due to the application-specific nature of wireless sensor networks, the sensitivity to such a requirement as data reporting interval varies according to the type of application. Such considerations require an application-specific, parameter tuning paradigm allowing us to maximize energy conservation prolonging the operational network lifetime. In this paper, we propose a reporting interval adaptive, sensor control platform for energy-saving data gathering in wireless sensor networks. The ultimate goal is to extend the network lifetime by providing sensors with high adaptability to application-dependent or time-varying, reporting interval requirements. The proposed sensor control platform is based upon a two phase clustering (TPC) scheme which constructs two types of links within each cluster - namely, direct link and relay link. The direct links are used for control and time-critical, sensed data forwarding while the relay links are used only for multi-hop data reporting. Sensors opportunistically use the energy-saving relay link depending on the user reporting, interval constraint. We present factors that should be considered in deciding the total number of relay links and how sensors are scheduled for sensed data forwarding within a cluster for a given reporting interval and link quality. Simulation and implementation studies demonstrate that the proposed sensor control platform can help individual sensors save a significant amount of energy in reporting data, particularly in dense sensor networks. Such saving can be realized by the adaptability of the sensor to the reporting interval requirements.

• Exercise Science
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• v.26 no.3
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• pp.223-228
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• 2017

PURPOSE: This study investigated the protective role of high-intensity interval training against acute liver injury induced by D-galactosamine (D-Gal)/lipopolysaccharide (LPS). METHODS: A total of 30 male BALB/c mice aged 5-week were randomly assigned to high-intensity, interval training group (EX, n=10) or control group in cage (Non-EX, n=20) for 10 weeks. Peritoneal injection of D-Gal (700 mg/kg body weight) and LPS ($10{\mu}g/kg$ body weight) was applied to induce acute liver injury, and liver tissue was harvested 6 hours after the injection. Hematoxylin and Eosin (H&E) staining was used for liver histology. Real-time PCR was used to quantify expression of pro-inflammatory and anti-inflammatory genes in the liver. RESULTS: The liver histology showed that D-Gal/LPS treatment resulted in hepatic damage and increased number of neutrophils in conjunction with upregulation of hepatic IL-6 and $TNF-{\alpha}$ mRNAs and downregulation of hepatic $PPAR{\alpha}$ and SIRT1 mRNAs. On the other hand, the 10-week interval training resulted in a significant improvement in cardiorespiratory fitness assessed as run time to exhaustion on a treadmill. In addition, the interval training attenuated the D-Gal/LPS-induced liver damage and increased number of neutrophil in conjunction with downregulation of hepatic IL-6 and $TNF-{\alpha}$ mRNAs and upregulation of hepatic $PPAR{\alpha}$ and SIRT1 mRNAs. CONCLUSIONS: This study suggests that high-intensity interval training suppresses the D-Gal and LPS-induced acute liver damage and inflammatory responses.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.194-198
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• 2005

Although the rainstorm causes local damage on large scale, it is difficult to predict the movement of the rainstorm exactly. In order to reduce the rainstorm damage of the rainstorm, it is necessary to analyze the path of the rainstorm using various statistical methods. In addition, efficient time interval of rainfall observation for the analysis of the rainstorm movement can be derived by applying various statistical methods to rainfall data. In this study, the rainstorm tracking using statistical method is performed for various types of rainfall data. For the tracking of the rainstorm, the methods of temporal distribution, inclined Plane equations, and cross correlation were applied for various types of data including electromagnetic rainfall gauge data and AWS data. The speed and direction of each method were compared with those of real rainfall movement. In addition, the effective time interval of rainfall observation for the analysis of the rainstorm movement was also investigated for the selected time intervals 10, 20, 30, 40, 50, and 60 minutes. As a result, the absolute relative errors of the method of inclined plane equations are smaller than those of other methods in case of electromagnetic rainfall gauges data. The absolute relative errors of the method of cross correlation are smaller than those of other methods in case of AWS data. The absolute relative errors of 30 minutes or less than 30 minutes are smaller than those of other time intervals.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.61-70
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• 2005

The objective of this study was to analyze the smoke movement for the case of fire and to determine the interval between emergency exits in long tunnels. Based on Froude modeling, the 1/50 scaled model tunnel (20 m long) was constructed by acrylic tubes and tests were carried out systematically. From the strong relationship between CO propagation time and distance through the tunnel, it was found that the optimal escaping time was 6 minutes in case of 20MW fire. But, regarding passengers' psychological state under fire, another one minute of delay time should be considered. Therefore, the total escaping time should be estimated by 5 minutes. The interval between the emergency exits for vehicle passengers was calculated by 250 m with respect to the 5 minute of escaping time.

• Physical Therapy Korea
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• v.17 no.3
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• pp.59-67
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• 2010

Mortality rates from stroke have been declining. Because of this, more people are living with residual disability. Rehabilitation plays an important role in functional recovery of stroke survivors. In stroke rehabilitation, early prediction of the obtainable level of functional recovery is desirable to deliver efficient care, set realistic goals, and provide appropriate discharge planning. The purpose of this study was to identify predictors of functional outcome after stroke using inpatient rehabilitation as measured by Functional Independence Measure (FIM) total scores. Correlation and stepwise multiple regression analyses were performed on data collected retrospectively from two-hundred thirty-five patients. More than moderate correlation was found between FIM total scores at the time of hospital admission and FIM total scores at the time of discharge from the hospital. Significant predictors of FIM at the time of discharge were FIM total scores at the time of hospital admission, age, and onset-admission interval. The equation was as follows: expected discharge FIM total score = $76.12+.62{\times}$(admission FIM total score)-$.38{\times}(age)-.15{\times}$(onset-admission interval). These findings suggest that FIM total scores at the time of hospital admission, age, and onset-admission interval are important determinants of functional outcome.