• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.643-646
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• 2005

The gas hydrate exploration using seismic reflection data, the detection of BSR(Bottom Simulating Reflector) on the seismic section is the most important work flow because the BSR have been interpreted as being formed at the base of a gas hydrate zone. Usually, BSR has some dominant qualitative characteristics on seismic section i.e. Wavelet phase reversal compare to sea bottom signal, Parallel layer with sea bottom, Strong amplitude, Masking phenomenon above the BSR, Cross bedding with other geological layer. Even though a BSR can be selected on seismic section with these guidance, it is not enough to conform as being true BSR. Some other available methods for verifying the BSR with reliable analysis quantitatively i.e. Interval velocity analysis, AVO(Amplitude Variation with Offset)analysis etc. Usually, AVO analysis can be divided by three main parts. The first part is AVO analysis, the second is AVO modeling and the last is AVO inversion. AVO analysis is unique method for detecting the free gas zone on seismic section directly. Therefore it can be a kind of useful analysis method for discriminating true BSR, which might arise from an Possion ratio contrast between high velocity layer, partially hydrated sediment and low velocity layer, water saturated gas sediment. During the AVO interpretation, as the AVO response can be changed depend upon the water saturation ratio, it is confused to discriminate the AVO response of gas layer from dry layer. In that case, the AVO modeling is necessary to generate synthetic seismogram comparing with real data. It can be available to make conclusions from correspondence or lack of correspondence between the two seismograms. AVO inversion process is the method for driving a geological model by iterative operation that the result ing synthetic seismogram matches to real data seismogram wi thin some tolerance level. AVO inversion is a topic of current research and for now there is no general consensus on how the process should be done or even whether is valid for standard seismic data. Unfortunately, there are no well log data acquired from gas hydrate exploration area in Korea. Instead of that data, well log data and seismic data acquired from gas sand area located nearby the gas hydrate exploration area is used to AVO analysis, As the results of AVO modeling, type III AVO anomaly confirmed on the gas sand layer. The Castagna's equation constant value for estimating the S-wave velocity are evaluated as A=0.86190, B=-3845.14431 respectively and water saturation ratio is $50\%$. To calculate the reflection coefficient of synthetic seismogram, the Zoeppritz equation is used. For AVO inversion process, the dataset provided by Hampson-Rushell CO. is used.

• Journal of the Korea Computer Graphics Society
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• v.23 no.1
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• pp.9-16
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• 2017

Simulating the clumping and stiffness of wet hair or fur is a challenging problem. The dynamics of wet hair or fur is characterized by the clumping and stiffness at the tip, which is easily seen in running animals or headbanging scenes. Existing methods address these phenomenon within pre-set scenarios. But there is no consensus on the method of depicting the details of wet hair. Hence, the present paper proposes a new method of modeling the clumping and stiffness of wet hair or fur. Previous studies focused on modeling the absorption of water into hair or fur, whereas this paper highlights a realistic simulation of wet hair. Unlike dry hair strands, wet hair strands adjacent to one another are subjected to the clumping force and gather together, while at the same time becoming stiff as the saturation of water increases. The proposed method builds on the surface tension model based on SPH (smoothed particle hydrodynamics) to simulate the clumping force and to adjust the hair elasticity by giving stiffness constraints. The present method enables a realistic simulation of wet hair by maintaining the clumping force of the wet hair even in dynamic motions, and by simulating the stiffness of hair in line with water saturation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.1
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• pp.97-108
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• 2016

The competition between countries became internationalized in the market. However, a situation in which globalization is concerned is important to domestic corporates. Corporate strategy to survive in the domestic market are also juggling the limit of survival. Technology transfer and commercialization at this point has important implications now. The same applies to the national level. Public-to-private technology transfer has been more important, in order to overcome the international competitions. Although various studies have been made to promote technology transfer, in the livestock sector rarely attempted. Taking into account that few previous research and theory development has been achieved, the paper explored the technology transfer phenomenon in the sector employing the grounded theory approach by Strauss & Corbin(1998). Corporates that licensed in technologies through the Foundation of Agri. Tech. Commercialization & Transfer, were targeted as informants or interviewees. Finally, eight informants were selected sequentially utilizing theoretical sampling technique to the saturation point. As the result of open coding and axial coding of the interview data using NVivo10 by QSR International, 77 concepts, 20 sub-categories, and 7 categories were derived while paradigm model was established. Through selective coding, 'the factors affecting technology transfer in livestock sector' was identified as core category. The story line about the core category was developed based on four main categories. Finally, it is expected that the concepts, categories, and the relationship between them can be an important basis for further research.

• Geotechnical Engineering
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• v.12 no.6
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• pp.115-126
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• 1996

The purpose of 1,his study is to analyze the compression and strength charactefistics of the decomposed -weathered soil originating from biotite gneiss or fine grained gneiss sampled from Poidong, Seoul : to figure out the behavioural characteristics of the decomposed -weathered soil in accordance with mineral composition and origin by comparing experimental results of residual soils. originating from granites and sampled from Bulam, Andong and Kimchun area. A series of CIU, CID CKoV, CKoD tests were car lied out. Although weathered soils have different origin and mineral composition, the slope of the NCL A was similar. It was also shown that plastic strain ratio was about 85% mainly due to the particle crushing effect during compression. The Poidong soil showed strain softening phenomenon unlike the Kimchun and Andong soils. this implies that the behavioural characteristics are affected by the origin and the mineral composition of the soil particles. Moreover, it was found that the angle of the shear resistance$(\phi')$ was dependent on the mineral composition. On the oher hand, measured Af values of decomposed weathered soils were more than one regardless of the origin and the mineral composition.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.2
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• pp.92-98
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• 2011

The influence of the cooling condition after solution treatment on the high temperature fatigue resistance of 23Cr-26Ni heat resistant steel was investigated. Two different cooling conditions were applied to the steel after solution treatment at $1200^{\circ}C$ for 3 hours. One specimen was water quenched immediately after the solution treatment. The other one was furnace cooled at a rate of $0.5^{\circ}C/min$ down to $750^{\circ}C$ after the solution treatment. Then, both specimens were aged at $750^{\circ}C$ for 5 hours. Under two different heat treatment conditions, the low cycle fatigue (LCF) test was performed at $600^{\circ}C$ and room temperature (RT). Only cyclic hardening continued from the beginning until fracture at all strain amplitudes during LCF at $600^{\circ}C$. This phenomenon was attributed to the increase in the dislocation density due to cyclic deformation, which resulted in the interaction between the newly created dislocations and precipitates. Cyclic hardening followed by saturation and cyclic softening was observed at RT. Cyclic softening was attributed to the dislocation annihilation rate exceeding the dislocation generation rate. Other probable factor for cyclic softening was some cavities formed around grain boundaries after 20 cycles. WQ and FC have a similar LCF behavior at RT and $600^{\circ}C$ as shown in the cyclic stress response curves.

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.2
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• pp.164-170
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• 2002

Sliding mode control, as a typical method of variable structure control, has the robust characteristics for the uncertainty and the disturbance of the nonlinear system. Because, however, sliding mode control input includes a sign function that Is discontinuous on the predefined switching surface, its applications are primarily limited by the need of alleviation or reduction of chattering. In this paper, we propose a chattering alleviation strategy based on a special nonlinear function and a fuzzy system. By using the proposed control scheme, we can reduce the steady state error. Its tracking performance is as fast as that of conventional method using the fixed boundary layer. Especially, in the proposed method, we can adjust the trade-off between the steady state error and the degree of chattering by regulating the proper range of the output variable of the fuzzy system. To verify the validity of the proposed algorithm, the analysis of the control method using the fixed boundary layer and the computer simulations are shown to compare with them.

• Journal of Korean Society of Transportation
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• v.26 no.1
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• pp.191-201
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• 2008

It has been employed TRANSYT-7F and NETSIM to evaluate the validity and effectiveness of improvement on TSM(Transportation Systems Management). But T7F is hard to describe platoon compression and dispersion in actually, and NETSIM takes a long time for network coding, calibration and have difficulty in setting up saturation flow. While Shockwave Model have advantage which can describe platoon compression and dispersion in actually and shorten hours, convenience of application. But Shockwave Model apply unrealistic traffic flow relation ship(U-K curve) and simplify platoon because of difficulty in calculating shockwave's position and cross. For solving limitation of existing shockwave models, It develop new model with 2-regime linear model, New platoon model, Extended shockwave, etc. For verifying the validity of the proposed model, it was compared with delay of T7F and NETSIM by offset variation. In conclusion, it is thought that proposed model have outstanding performance to simulate traffic phenomenon.

• Research in Community and Public Health Nursing
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• v.13 no.4
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• pp.732-742
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• 2002

There are few research on the social drinking experience reported by women. Thus, it is necessary to understand the increasing tendency of womens drinking experience in the sociocultural context. This study was aimed to explore and delineate the drinking experience of full-time house wives base don Strauss and Corbin's grounded theory (1998). The subjects of this study were 10 full-time middle-aged house wives who were living in Seoul region. The data were collected through several in-depth interviews and observations until the theoretical saturation was achieved. The data were analyzed using Strauss and Corbin's grounded theory method. The results of this study generated a paradigm that the drinking experience of the full-time middle-aged house wives has a core category of 'free-oneself-from' and is also connected with mingling, anguish, accessibility, reaction of other people, change, personal resources, self-expression and building relationships by drinking. All processes from the occurrence of the central phenomenon to extinction are as follows; 1) Starting the process of the drinking experience for mingling and resolving anguish, and by having an easy accessibility; 2) Perceiving the process of reaction by other people, physical change of herself. and psycho-behavioral change; 3) Experiencing the process of free-oneself from thorough drinking; 4) Acknowledging the process of the resources for free-oneself-from; 5) Selecting the process of self-expression according to the resources; 6) Building the process of the relationship with drinking as a way of self-expression. Based on this paradigm, 4 hypothesis and 4 types are generated. Thus, this study suggests that it is useful to develop nursing interventions to improve the self-esteem of the full-time middle-aged house wives and to provide them various methods of problem solving strategies. This study also proposes that there should be a strategic program for the women so that they could make a route for positive self-expression by achieving a proper relationship with drinking.

• Journal of the Korea Convergence Society
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• v.8 no.8
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• pp.203-213
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• 2017

The purpose of this research is to suggest the direction of the domestic convenience store platform in the aging society and the fourth industrial revolution. Recently, convenience stores have been providing various lifestyle platforms by seeking new growth engines based on the reputation that the number of convenience stores has reached the saturation. In order to present the direction of development, It conducted a questionnaire survey of 78 people from domestic teenagers to 60s or older and case study of domestic and overseas convenience store platforms. Through this survey, it was found that convenience stores in Korea provide users with a convenient lifestyle platform, but the service for the elderly was found to be in shortage compared to other countries. Convenience stores should offer lifestyle platform services for the elderly, as they provide lifestyle platform services for people in 20s and 30s. This will make the convenience store a competitive lifestyle platform service in the 4th industrial revolution. In addition, it is necessary to continuously study the CVS living platform service according to the changing social phenomenon in the future.

• Journal of Soil and Groundwater Environment
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• v.21 no.5
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• pp.8-15
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• 2016

Bioremediation, which uses microbes to degrade most organic pollutants in soil and groundwater, can be used in solving environmental issues in various polluted sites. In this research, a wind-driven bioventing system is built to degrade about 20,000 mg/kg of high concentration diesel pollutants in soil-pollution mode. The wind-driven bioventing test was proceeded by the bioaugmentation method, and the indigenous microbes used were Bacillus cereus, Achromobacter xylosoxidans, and Pseudomonas putida. The phenomenon of two-stage diesel degradation of different rates was noted in the test. In order to interpret the results of the mode test, three microbes were used to degrade diesel pollutants of same high concentration in separated aerated batch-mixing vessels. The data derived thereof was input into the Haldane equation and calculated by non-linear regression analysis and trial-and-error methods to establish the kinetic parameters of these three microbes in bioventing diesel degradation. The results show that in the derivation of μ_m (maximum specific growth rate) in biodegradation kinetics parameters, K_s (half-saturation constant) for diesel substance affinity, and K_i (inhibition coefficient) for the adaptability of high concentration diesel degradation. The K_s is the lowest in the trend of the first stage degradation of Bacillus cereus in a high diesel concentration, whereas K_i is the highest, denoting that Bacillus cereus has the best adaptability in a high diesel concentration and is the most efficient in diesel substance affinity. All three microbes have a degradation rate of over 50% with regards to Pristane and Phytane, which are branched alkanes and the most important biological markers.