• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.251-256
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• 2012

Stilbenes are known as antioxidants and some of them demonstrate anti-pigmentation activity. The purpose of the present study was to investigate whether two stilbene compounds produced by biotransformation of the extract of $Morus$ $alba$ root show skin irritation and sensitization. In skin irritation test, 1% oxyresveratrol (OXY), and 5% OXY, and 1% oxyresveratrol-3-$O$-glucoside (OXY-3) showed a P.I.I score of 0, 0.04, and 0, respectively. Accordingly, the two stilbenes were evaluated to be virtually 'non-irritant' materials. In a skin sensitization study by GPMT, 1% OXY, 5% OXY, and 1% OXY-3 did not cause edema and erythema at 24 h and 48 h after topical application and exhibited a sensitization score of 0 and a rate of 0%. Consequently, it was confirmed that OXY and OXY-3 had no contact allergic sensitization in GPMT. Therefore, OXY and OXY-3 might be potential candidates as skin-whitening agents without posing any serious side effects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4831-4843
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• 2014

Magazines on specific genres have been operating collaborative, co-working and collective production systems for value maximization using an adaptation strategy on the dynamic, complex and uncertain value network of the magazine industry. The study used a case study method, and data collection was performed by observational research, depth interviews and survey research. The subjects of the study were 'magazine industry', 'magazine firm and community', and 'collaboration system within creative users'. According to the research results, the ecosystem of magazines on a specific genre has been evolving into an innovative value network system, which is combined with the magazine firm, community users and magazine platform. Second, the rapid introduction of smart device environment changes the way of the collaborating system, in which an action and interaction came out within the community, creative users and magazine firms. Third, the production agency shows strong action and interaction, which fits the magazine platform within the ecosystem of a magazine on a specific genre well. This model has a similar fractal structure to the game, publishing, drama, movie, comic, and animation contents industry, converging to an innovative technology-based-creative-industry.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.143-155
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• 2013

In order to establish efficient timber harvesting system and provide the necessary data for the system establishment, the techniques to identify areas possible of the yarding-operation and design forest-road networks were newly developed and the applicability of the techniques are tested in this study. The new techniques were developed based on ArcGIS, particularly with utilizing the Viewshed Analysis Tool. From the results of the identification of the possible yarding-operation areas, it is found that the percentage of possible yardingoperation area decreases with the increment of maximum yarding distance due to terrestrial effects. When forest road networks are extended in impossible yarding-operation sites, the area of possible yarding-operation sites increases. If a forest road network is newly designed, its overall extension is altered, resulting in changes in the possible yarding-operation areas. Through the comparative analysis among the different possible yardingoperation areas from different forest road networks, the maximization of the yarding-operation possible area can be achieved. The results from this study can be utilized for establishing more efficient timber-harvesting system and developing GIS-based programs to manage the system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11A
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• pp.1081-1091
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• 2005

Unlike conventional DVB-T transmission with the streaming method, DVB-H system based on the IPDC(IP Data Casting) method uses Time-slicing scheme to achieve the maximization of portability by reducing the power consumption of a receiver. To enhance the power efficiency of the receiver, Time-slicing scheme controls the receiver operation to perform only for corresponding burst in specific time slot. The additional power saving can also be achieved by reducing the required time for synchronization. In this paper, we propose a fast scattered pilot synchronization algorithm, which detects the pilot pattern of currently received OFDM symbol. The proposed scheme is based on the correlation between the adjacent subcarriers of potential scattered pilot position in two consecutively received OFDM symbols. Therefore, it can reduce the time for the scattered pilot synchronization within two symbols as com-pared with the conventional method used for DVB-T. And the proposed algorithm has better performance than the two schemes proposed by Nokia for DVB-H and the method using correlation with reference signal. Extensive com-puter simulation is performed based on ETSI EN300 744 ETSI and performance results show that the proposed algorithm has more efficient and stable operation than the conventional schemes.

• The Journal of the Acoustical Society of Korea
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• v.24 no.3
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• pp.141-149
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• 2005

Tn general. Gaussian mixture model (GMM) is used to estimate the speaker model from the speech for speaker identification. The parameter estimates of the GMM are obtained by using the Expectation-Maximization (EM) algorithm for the maximum likelihood (ML) estimation. However the EM algorithm has such drawbacks that it depends heavily on the initialization and it needs the number of mixtures to be known. In this paper, to solve the above problems of the EM algorithm. we propose an EM algorithm with the initialization based on incremental ${\cal}k-means$ for GMM. The proposed method dynamically increases the number of mixtures one by one until finding the optimum number of mixtures. Whenever adding one mixture, we calculate the mutual relationship between it and one of other mixtures respectively. Finally. based on these mutual relationships. we can estimate the optimal number of mixtures which are statistically independent. The effectiveness of the proposed method is shown by the experiment for artificial data. Also. we performed the speaker identification by applying the proposed method comparing with other approaches.

• Journal of Korea Water Resources Association
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• v.31 no.6
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• pp.727-739
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• 1998

The main objectives o reservoir optimal operation can be described as follows : maximization of the benefits through optimal allocation of the limited water resources for various purpose; minimization of t도 costs by the flood damage in potential damaging regions and risk of dam failure, etc. through safe drainage of a bulky volume of excessive water by a proper reservoir operation. Reviewing the past research works related to reservoir operation, we can find that the study on the matter of the former has been extensively carried out in last decades rather than the matter of the latter. This study is focused on developing a methodology of optimal reservoir operation for flood control, and a case study is performed on the Chungju multipurpose reservoir in Korea. The final goal of the study is to establish a reservoir optimal operation system which can search optimal policy to compromise two conflicting objectives: downstream flood damage and dam safety-upstream flood damage. In order to reach the final goal of the study, the following items were studied : (1)validation of hydrological data using HYMOS: (2)establishment of a downstream flood routing model coupling a rainfall-runoff model and SOBEK system for 1-D hydrodynamic flood routing; (3)replication of a flood damage estimation model by a neural network; (4)development of an integrated reservoir optimization module for an optimal operation policy.

• Journal of Digital Contents Society
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• v.19 no.7
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• pp.1365-1372
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• 2018

The purpose of this study is to analyze the importance of the determinants of housing sales agency's role in the sale of apartment housing. For this purpose, a hierarchical decision model was constructed to understand the role and importance of the sales agency. The analytical variable items structured by the research model were set up through literature review, precedent research, and expert brainstorming. The questionnaire consisted of two comparisons for AHP analysis and the importance of absolute importance for fuzzy analysis. Afterwards, the work of correcting the importance was carried out. As a result of the analysis, it was found that the contractor prioritized the sale conditions and the sales agency had priority over the planning for the sale. As a result of analysis, planning of customer pre-sale counseling data, planning of client subscription and contract maximization plan, planning method of advertisement public media method were found to be the most important factors. The results of measurement of absolute importance(fuzzy) & relative importance(,AHP) showed similar tendency. Therefore, it can be seen that the timing of the model house operation is an important period in which the subscription rate depends on the role of the sales agency and the marketing strategy.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.93-102
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• 2012

The purpose of this research is to create a preferable corporate culture under the SmartWork environment. There is growing interests in SmartWork, which can satisfy the compatible conditions of government's carbon emission restriction policy, corporate efficient expense reduction, productivity maximization, and each individual's work and a family. Due to the interests and the rapid development of IT technology, a realistic condition for SmartWork is established but the promotion without a sufficient preparation, such as legal examination and relevant systems, created much confusion and very few companies are introducing it. This paper discusses that a social agreement should be reached through adjustments among parties interested, such as government, companies, and employees, studies the WIN-WIN plan that individuals and organization can grow together, and proposes a new corporate culture under the SmartWork environment. SmartWork has more than the simple meaning of 'remote working'. SmartWork, a method of smart working, means a transition to a new paradigm that minimizes moving for work and work & human move together, and a change from a work-oriented culture to a human-oriented culture. This paper summarized the role of government and companies for the successful introduction of SmartWork, and proposed that a government level 'SmartWork Activation Executive Committee (tentative name)' with a strong promotional power would create a new culture of SmartWork and form a civilian consultative body to support SmartWork corporate culture creation & expansion in the private corporate area, in a tuning with Ministry of Public Administration & Security, Ministry of Labor, Ministry of Gender, and Communications Commission.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.268-273
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• 2008

Because a procedure is complicated and various related parties participate in the redevelopment and reconstruction project, it can be extended to diverse disputes when the relation with the related parties is smoothly adjusted. In particular, when the dispute occurs in a phase of occupancy after the complete construction, the regional residents-centric association must give up many rights of invisible parts caused by the construction company's profit maximization because they are short of professionalism about the business. Accordingly, this study is aimed at providing the construction project manager's dispute and claim process for responding to the dispute or claim reasonably and for obtaining the client's (association) rights for the reconstruction project, and at developing the checklist for obtaining the necessary documents by each phase, when the dispute or claim is made by the association against the construction company after the completion of construction. Through this study, the association can obtain the related documents in advance and can implement the reasonable response data when the dispute or claim occurs due to it. Also, it will enable the construction manager to analyze the project costs reasonably and will reduce the estimated wastes. That is, the work efficiency is expected to be improved.

• Journal of the Korean Applied Science and Technology
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• v.24 no.1
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• pp.31-46
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• 2007

This study was focused on the maximization of flame-retardancy of polyesters by a synergism of simultaneously introduced chlorine and phosphorus into polymer chains of modified polyesters. To prepare modified polyesters, reaction intermediates, TD-adduct (prepared from trimethylolpropane/2,4-dichlorobenzoic acid (2,4-DCBA)) and TMBO (prepared from tetramethylene bis(orthophosphate)), were prepared first, then condensation polymerization of the prepared intermediates, adipic acid, and 1,4-butanediol were carried out. In the condensation polymerization, the content of phosphorus was fixed to be 2%, and the content of 2,4-DCBA that provides chlorine component was varied to be 10, 20, and 30wt%, and we designated the prepared modified polyesters containing chlorine and phosphorus as ABTT-10C, -20C, -30C. Two-component PU flame-retardant coatings (ABTTC, ABTTC-10C, ABTTC-20C, ABTTC-30C) were prepared by the curing of synthesized ABTTs with a curing agent of allophanate/trimer at room temperature. To examine the film properties of the prepared PU flame-retardant coatings, film specimens were prepared with the prepared coatings. The film properties of ABTTC, ABTTC-10C and ABTTC-20C, which contain 0, 10 and 20wt% 2,4-DCBA, respectively, were proved to be good, whereas the film properties of ABTTC-30C, which contains 30wt% 2,4-DCBA, was proved to be a little bit poor. Two kinds of flame retardancy tests, $^{\circ}45Meckel$ burner method and LOI method were performed. With the $^{\circ}45Meckel$ burner method, three flame-retardant coatings except ABTTC showed less than 3.4cm of char length, and showed less than 2 seconds of afterflaming and afterglow. From this result, the prepared flame-retardant coatings were proved to have the 1st grade flame retardancy. With the LOI method, the LOI values of the coatings containing more than 10wt% 2,4-DCBA were higher than 30%, which means that the coatings possess good flame retardancy. From these results, it was found that synergistic effect in flame retardancy was taken place by the introduced phosphorus and chlorine.