• Journal of the Korean Geotechnical Society
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• v.20 no.5
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• pp.79-86
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• 2004

Interfacial properties between rock mass and shotcrete play a significant role in the transmission of loads from the ground to shotcrete. These properties have a major effect on the behaviours of rock mass and shotcrete. They, however, have merely been considered in most of numerical analyses, and little care has been taken in identifying them. This paper aimed to identify interfacial properties including cohesion, tension, friction angle, shear stiffness, and normal stiffness, through direct shear tests as well as interface normal compression tests for shotcrete/rock cores obtained from a tunnel sidewall. Mechanical properties such as compressive strength and elastic modulus were also measured to compare them with the time-dependent variation of interfacial properties. Based on the experiments, interfacial properties between rock and shotcrete showed a significant time-dependent variation similar to those of its mechanical properties. In addition, the time-dependent behaviours of interfacial properties could be well regressed through exponential and logarithmic functions of time.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.2
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• pp.160-167
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• 2017

The purpose of this study is to identify the possibility of developing the 100% Recycled-resources Absorbent-Pervious Alkali-activated Blocks using both the alkalli-binder and the recycled aggregate. In addition, It established a test method such as Void ratio, compressive strength, coefficient permeability, absorption, and evaporation. As a result, an alkali-activated using recycled aggregate block was able to manufacture an 24 MPa class absorbent-pervious blocks with a liquid type sodium silicate and early high temperature curing. In this case, water-holding capacity, absorption and relative absorption were more effective than the natural aggregates. In conclusion, Absorbent-pervious alkali-activated Block Using recycled aggregate has a surface temperature reducing effect of approximately 10 % compared to ordinary concrete block.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.18 no.1
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• pp.39-48
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• 2012

Background: This study was performed to identify what effect plyometric exercise with application of kinesio taping gives on muscle activity and power of lower limb. Methods: In order to conduct research, total 14 male students at G university located Gwangyang city were randomly assigned; 7 for experimental group (with kinesio taping application) and 7 for control groups(without kinesio taping application) were conducted with box drill, one of the plyometric exercise 5 times a week for 4 weeks. Muscle activities were measured by using electrodiagnosis equipment on quadriceps and gastrocnemius. Collected data was analyzed by using Windows SPSS version 19.0. Results: Muscle activities show statistically significant differences (p<.05) both before and after exercise in experimental and control groups in terms of vastus medialis, rectus femoris, vastus lateralis and lateral gastrocnemius. However, only medial gastrocnemius shows statistically significant differences in experimental group compared before and after exercise. Sargent jump for measuring power shows that only experimental group presents statistically significant differences (p<.05). Two groups show that vastus medialis, vastus lateralis, lateral gastrocnemius and medial gastrocnemius only in muscle activities show statistically significant differences (p<.05) after exercise. Conclusion: The result of this survey indicates that plyometric exercise is effective to improve muscle activity and power of lower limb, especially, the group who exercises with application of kinesio tape is more effective than the other group with no tape application. Therefore, it is considered that plyometric exercise with tape is more effective to improve power and muscle strength.

• Physical Therapy Korea
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• v.11 no.3
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• pp.1-9
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• 2004

Most exercise for Patellofemoral pain syndrome (PFPS) has focused on selectively strengthening the vastus medialis oblique muscle (VMO). Although open chain knee extension exercises are effective for increasing overall quadriceps strength, they are not always indicated for PFPS rehabilitation. This study was designed to identify the effect of combined posture of lower extremity on Electromyographic (EMG) activity of the vastus lateralis muscle (VL) and VMO during static squat exercises. The subjects were twenty young adult males who had not experienced any knee injury and their Q-angle was within a normal range. They were asked to perform static squat exercises in five various postures using their lower extremities. The EMG activity of the VL and VMO were recorded in five exercises by surface electrodes and normalized by %MVC values derived from seated, isometric knee extensions. The normalized EMG activity levels (%MVC) of the VL and VMO for the five postures of the lower extremities were compared using one way ANOVA with repeated measures. Results of repeated measures of ANOVA's revealed that exercise 3 and exercise 5 produced significantly greater EMG activity of VMO/VL ratios than exercise 1 (p<.05). When the static squat exercise was combined with hip adduction and toes pointed outwardly, the EMG activity of VMO/VL rates was increased. The EMG activity of VMO/VL ratio was highest during static squat exercises performed on a decline squat. These results haveimportant implications for progressive and selective VMO muscle strengthening exercises in PFPS patients.

• Korea Journal of Hospital Management
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• v.9 no.1
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• pp.95-114
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• 2004

The purpose of this study was to identify the relationship between organizational culture based on the competing values approach, human resource management practices and organizational performance at a hospital. Participants were 138 employee in a general hospital. Data were collected during May, 2003 using four structured instruments. The data were analyzed using Chi-square test, One-way ANOVA, $scheff{\acute{e}}$ test and Cluster analysis. Three clusters were derived from cluster analysis. The first cluster consisted of cultures which were mixed developmental, consensual, hierarchial and rational culture equivalently. The second cluster consisted of the weak cultures, which was lower score than other clusters. The third cluster consisted of strong comprehensive cultures, which had higher score than other clusters. In the three clusters, hierarchial and rational culture were superior. The difference between human resource management practices and organizational commitment in organizational performance according to organizational culture clusters was found to be statistically significant. The cluster which had strong comprehensive cultures, in contrast to other clusters, more significantly affects on human resource management practices and organizational commitment. However, the strength of organizational culture does not have a significant effect on customer oriented service performance in organizational performance. These results showed that types of organizational culture were significantly related to human resource management practices and organizational commitment, and understanding the existing culture is essential to develop the organization of hospitals.

• Journal of Hydrogen and New Energy
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• v.28 no.2
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• pp.174-180
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• 2017

Recently, the world faces the environmental problem such as air pollution due to harmful gas discharged from car and abnormal climate due to the green-house gases increased by the discharge of $CO_2$. Compressed Natural Gas (CNG), one of alternative for this problem, is less harmful, compared to the existing fossil fuel, as gaseous fuel, and less carbon in fuel ingredients and carbon dioxide generation rate relatively favorable more than the existing fuel. However, CNG fuel has the weakness of slow flame propagation speed and difficult fast burn. On the other hand, hydrogen does not include carbon in fuel ingredients, and does not discharge harmful gas such as CO and HC. Moreover, it has strength of quick burning velocity and ignition is possible with small ignition energy source and it's has wide Lean Flammability Limit. If using this hydrogen with CNG fuel, the characteristics of output and discharge gas is improved by the mixer's burning velocity improved, and, at the same time, is possible to have stable lean combustion with the reduction of $CO_2$ expected. Therefore, this research tries to identify the characteristics of engine and emission gas when mixing CNG fuel and hydrogen in each portion and burning them in spark igniting engine, and grasp the lean combustion limit and emission gas characteristics according and use it as the basic data of hydrogen-CNG premixed engine.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.2
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• pp.132-141
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• 2017

The objective of this study was to provide fundamental information on fish swimming behavioral properties. Acoustic data was collected at nighttime from the $10^{th}$ to $12^{th}$ March, 2016 near Yokji Island in the South Sea of South Korea, and was analyzed using the fish track technique. This technique is to identify groups of single targets, which shows a pattern of systematic movement. As a result, the differences of the behavioral properties such as depth, swimming speed, vertical direction, horizontal direction, tortuosity, and depth change among days were minor; however, statistical results (Welch analysis of variance) showed significant difference between days. Especially, the target strength (TS) of the $11^{th}$ were significantly different from the $10^{th}$ and $12^{th}$. It could be assumed that gizzard shad, which was the dominant species from the catch on the $11^{th}$ March, might have affected this difference. The correlation between TS and other properties was very week. The significant difference seemed even small differences of average values because of the large data volume.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.299-305
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• 1998

It was investigated to identify the volatile compounds of commercial vinegars by dynamic headspace sampling GLC-mass spectrometry, and additionally to evaluate the difference of sensory odor properties among vinegars such as brewed, cider, brown rice and persimmon vinegars. Thirty compounds were identified in four kinds of vinegar, which were composed of 9 carbonyl compounds, 12 esters, 6 alcohols and 3 acids. 3-Hydroxy-2-butanone could be merely detected in some of vinegar samples, and persimmon vinegar was characterized to include more various alcoholic compounds compared to the other kinds of vinegar. 3-Methyl-1-butanol was not detected from any samples of brewed vinegar, but from the most of cider, brown rice and persimmon vinegars. Persimmon vinegar has shown high strength of background odor intensity, and consequently was appeared to be inferior in background (p<0.05) and overall(p<0.01) odor preference scores to cider, brewed and brown rice vinegars.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.248-251
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• 2000

Electron spin resonance (ESR) spectroscopy was used to detect irradiated chicken eggs, to investigate the effect of irradiation dose on the ESR signal intensity and to identify the stability of radicals under 77 days of storage. Raw chicken eggs were irradiated with doses of 0, 0.5, 1, 2, 3 and 5 kGy at room temperature using a Co-60 irradiator. The samples were prepared by separating, drying and powdering shells from the raw eggs. The irradiated chicken egg shells presented an asymmetric absorption in shape at g$_1$=2.0023$\pm$0.00004 and g$_2$=1.9979$\pm$0.00005, different from the non-irradiated ones. The strength of the ESR signal increased linearly with the applied doses (to S kGy). The intensity of the ESR signals after irradiation were stable even after 77-day of storage at 5$^{\circ}C$ and/or room temperature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3451-3457
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• 2010

Cyber security assessment is the process of determining how effectively an entity being assessed meets specific cyber security objectives. Cyber security assessment helps to measure the degree of confidence one has and to identify that the managerial, technical and operational measures work as intended to protect the I&C systems and the information it processes. Recently, needs for cyber security on digitalized nuclear I&C systems are increased. However the overall cyber security program, including cyber security assessment, is not established on those systems. This paper presents the methodology of cyber security assessment which is appropriate for nuclear I&C systems. This methodology provides the qualitative assessments that may formulate recommendations to bridge the security risk gap through the incorporated criteria. This methodology may be useful to the nuclear organizations for assessing the weakness and strength of cyber security on nuclear I&C systems. It may be useful as an index to the developers, auditors, and regulators for reviewing the managerial, operational and technical cyber security controls, also.