• Journal of Korean Society of Steel Construction
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• v.26 no.1
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• pp.43-53
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• 2014

A single plate connection(SPC) consists of a plate welded to the columns and bolts connected to the beam web. The SPC is widely used for a simple shear connection of steel structure because it is easy-to-fabricated, easy-to-installed and economical. The conventional SPC is used for 2 to 12 bolts in a single vertical row. It is designed to limit the plate thickness by bolt diameter to obtain flexible and ductile connections. The design strength for eccentric shear shall be the lesser of the shear strength of bolts or bearing strength of plate and when the design strength is decided by edge distance failure, the results can be very conservative. Although the research on special solution for 'weak-plate/strong-bolt' model with 2 to 4 bolts has been conducted by L. S. Muir, and W. A. Thonton, 2004, study on generalized design procedures did not conduct. This study proposed design procedure for evaluation of the design strength of eccentric shear bolt groups on a single plate connection based on the actual edge distance and the direction of bolt reaction forces by using elastic vector method(EVM) and instantaneous center of rotation method(ICM).

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.130.2-130.2
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• 2013

Today, chemical vapor deposition (CVD) of hydrocarbon gases has been demonstrated as an attractive method to synthesize large-area graphene layers. However, special care should be taken to precisely control the resulting graphene layers in CVD due to its sensitivity to various process parameters. Therefore, a facile synthesis to grow graphene layers with high controllability will have great advantages for scalable practical applications. In order to simplify and create efficiency in graphene synthesis, the graphene growth by thermal annealing process has been discussed by several groups. However, the study on growth mechanism and the detailed structural and optoelectronic properties in the resulting graphene films have not been reported yet, which will be of particular interest to explore for the practical application of graphene. In this study, we report the growth of few-layer, large-area graphene films using rapid thermal annealing (RTA) without the use of intentional carbon-containing precursor. The instability of nickel films in air facilitates the spontaneous formation of ultrathin (<2~3 nm) carbon- and oxygen-containing compounds on a nickel surface and high-temperature annealing of the nickel samples results in the formation of few-layer graphene films with high crystallinity. From annealing temperature and ambient studies during RTA, it was found that the evaporation of oxygen atoms from the surface is the dominant factor affecting the formation of graphene films. The thickness of the graphene layers is strongly dependent on the RTA temperature and time and the resulting films have a limited thickness less than 2 nm even for an extended RTA time. The transferred films have a low sheet resistance of ~380 ${\Omega}/sq$, with ~93% optical transparency. This simple and potentially inexpensive method of synthesizing novel 2-dimensional carbon films offers a wide choice of graphene films for various potential applications.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.5 no.1
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• pp.48-58
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• 1995

This study was performed to find out the exposure level of mixed organic solvents, excretion of urinary hippuricacid and subjective symptoms according to the exposure of organic solvents of female workers who works on 5 shoes manufacturing industries in Taejon City from 24, september to 20, october 1993. The studied groups were divided into 3 groups that were consist of direct exposure group(48 workers), indirect exposure group(49 workers) and non-exposure group(68 workers) to the organic solvents. The exposure levels of toluene of direct exposure group which $89.86{\pm}56.20ppm$ had higher than that of indirect exposure group which had $40.23{\pm}47.21ppm$. In the exposure level of mixed organic solvent(R-value), direct exposure group was $2.84{\pm}1.53$ and exceeded approximatly 3 times the R-value. Whereas, indirect exposure group was not exceeded the R-value as $0.80{\pm}0.61$. In the excretion level of urinary hippuric acid, direct exposure group was $1.78{\pm}1.25g/l$, indirect exposure group was $1.22{\pm}0.93g/l$ and non-exposure group was $0.51{\pm}0.18g/l$ respectively. Therefore both direct exposure group and indirect exposure group were significantly higher than non-exposure group(P<0.01). In the correlation between toluene levels and urinary hippuric acid level, the direct exposure group had positive correlation(R=0.8309, P<0.01), also indirect exposure group had positive correlation(R=0.5859, P<0.05) and also in the correlation between the R value of mixed organic solvents and the urinary hippuric acid levels, the direct exposure group had positive correlation(R=0.4492, P<0.05), and indirect exposure group had ositive correlation(R=0.7911, P<0.01). In the complain rates of the worker's subjective symptoms at work, both direct exposure group and indirect exposure group were higher than non-exposure group(P<0.05, P<0.01). But the sujective symptoms of "floating sensation" of direct exposure group had significantly higher than indirect exposure group. In the percent of subjective symptoms complaints during the worker's daily life, both direct exposure group and indirect exposure group had generally more statistical significance than nonexposure group(P<0.01), direct exposure group had not statistical significant difference from indirect exposure group. As the results mentioned above, it has been analysed that the indirect at the adjacent manufaturing process are exposed to the considerable amount of solvent. Therefore, I think that there should be the betterment of surrounding through the complete working environment management to the occurrence source of the organic solvent, the changes of health management system to the indirect-exposed workers, and the systematic management of the special medical examination and the like.

• Journal of the Korean Society for Library and Information Science
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• v.16
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• pp.207-242
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• 1989

This study hypothesizes that the present deadlock situation in public library development in Korea has chiefly been caused by the underdevelopment of the consciousness of the librarians themselves presently employed in various levels of public libraries throughout the country. This study, therefore, aims to define the areas in librarians' consciousness in which elements of backwardness prevail, and thereby to produce a theoretical framework to develop public library services in Korea on an indigenous footing. To do this, the present author set up a relationship between the traditional consciousness of the Korean People and the public library performances, based on existing published materials. In order to prove hisirelatonship, he then sent out questionnaires to public librarians and male high school students and analyzed the answered questionnaires using Pearson's Correlation Analysis and Multiple Regression Analysis. Results of the analysis are asfollows: 1) Those who place an importance on the show of respectability tend to prefer to work in an indirect services area. 2) Male librarians tend to show a job satisfaction because of chances of promotion reflecting a positive correlation between this-worldiness of librarians and their job satisfaction. 3) Male librarians tend to be satisfied in their job for the conviction for their self-accomplishment, and female librarians tend to be satisfied in their job for the attention and respect they receive from users. 4) Library technicians tend to draw their job satisfaction from their sense of job stability. 5) Male librarians tend to be dissatisfied for the lack of the monetary rewards they receive, while female librarians tend to be dissatisfied for the lack of promotional chances. 6) Most librarians tend to maintain a positive job attitude for the promotional chances, reflecting a positive correlation between this­worldliness in librarians and their service attitude. 7) Power-orientednes in librarians and their job satisfaction correlate negatively in the case of male librarians. This does not apply to female librarians. 8) Power-orientedness and good service attitude correlate negatively in the case of male librarians. This does not apply to female librarians. 9) The fact that male high school students desire to enter good colleges and universities and to obtain a position in his job positively correlate to the fact that public libraries have transformed themselves into a mere reading room. 10) Male library science students show a maladjustment in their major department in earlier years for the professional uncertainty, and as they advance into senior years they show a positive attitude about the library profession.

• Journal of fish pathology
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• v.26 no.3
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• pp.241-254
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• 2013

In order to establish bio-marker systems for the screening of endocrine-disrupting chemicals contaminated in various environment, Vitellogenin(Vtg) bio-marker have been developed to detect Scorpion fish's(Sebastiscus marmoratus) Vtg. Vtg has been induced by administration of estradiol into S. marmoratus, and purified by gel filtration and ion-exchange chromatography from serum of the fish. After immunization of the purified Vtg into BALB/c mouse, hybridomas secreting anti-Vtg antibodies have been produced. The size of induced Vtg in the serum was about 440 kDa by gel filtration using Sepharose CL-6B. By SDS-PAGE analysis, the main band of Vtg, however, was at 175 kDa, and several minor bands have been detected with the main band. Eight different monoclonal antibodies have been produced from established hybridomas and the antibodies did not cross-react with sera from different species of fishes tested in this study except with that of Sebastes hubbsi. These results suggested that the monoclonal antibody of S28 and S15 can used as capture and tracer antibodies for ELISA and ICG assays. The detection systems developed in this study can be used as Bio-marker assays to check endocrine disrupting activity of various chemicals as well as to detect known endocrine disrupting chemicals contaminated in environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.527-535
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• 2017

Heat management is one of the most critical issues in Polymer Electrolyte Membrane Fuel Cells (PEMFCs) installed inside the fuel cell power pack of a fuel cell battery hybrid UPS. If the heat generated by the chemical reaction in the fuel cell is not rapidly removed, the durability and performance of the fuel cell may be affected, which may shorten its lifetime. Therefore, the objective of this study is to select and propose a proper cooling method for the fuel cells used in the fuel cell power pack of a UPS. In order to find the most appropriate cooling method, the various design factors affecting the cooling performance were studied. The numerical analysis was performed by a commercial program, i.e., COMSOL Multiphysics. Firstly, the surface temperature of the 1 kW class fuel cell stack with the cooling fans placed at the top was compared with the one with the cooling fans placed at the bottom. Various rotation speeds of the cooling fan, viz. 2,500, 3,000, 3,500, and 4,000 RPM, were tested to determine the proper cooling fan speed. In addition, the influence of the inhaled air flow rate was investigated by changing the porous area of the grille, which is the entrance of the air flowing from the outside to the inside of the power pack. As a result, it was found that for the operating conditions of the 1 kW class PEMFC to be acceptable, the cooling fan was required to have a minimum rotating speed of 3500 RPM to maintain the fuel cell surface temperature within an acceptable range. The results of this study can be effectively applied to the development of thermal management technology for the fuel cells inside the fuel cell power pack of a UPS.

• Journal of Distribution Science
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• v.14 no.4
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• pp.39-46
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• 2016

Purpose - Recently, as Korean culture and economy develops, Seoul has become a world-famed city. In Seoul, many special grade hotels have been constructed in order to accommodate many tourists from China, Japan and many other Asian countries. And the hotels entered into competition among themselves. Thus many changes are accelerated due to their mutual competition and manpower problems. In this situation, the role of higher officers above all is thought to be very important in order to enhance the management result and to make preparations for the kernel ability of the organization. Research design, data and methodology - This study was intended to verify how the leadership of the higher officers based on trust affects the job satisfaction of employees of the organization. In order to achieve the purpose of this study, some study models and hypotheses have been established through theoretical examinations. The subjects of this study were centered on the constituents of C-Hotel, M-Hotel, and D-Hotel. 200 questionaries were distributed and 190 questionaries were collected and thus the collection ratio was 91 percent. 8 questionaries which were regarded to be insincere or hard to analyzed were excluded. Finally, 182 questionaries were used for analyzing the factors and trust. For the purpose of the verification of hypotheses, structural equation was used. In order to verify the mediating effect of trust between the relationship of emotional leadership and job satisfaction, 'Three-step Mediated Regression Analysis by Baron & Kenny(1986) was utilized. The four hypotheses for this study are as follows: First, emotional leadership will have a meaningful influence on trust in the affirmative. Second, trust will have a meaningful influence on job satisfaction in the affirmative. Third, trust will play a mediating role in the relationship of emotional leadership and job satisfaction. Result - First, the emotional leadership and trust was found to effect a positive effect. Second, the trust and job satisfaction was found on a positive effect on job satisfaction. Third, the emotional leadership and job satisfaction was found to positive effect on job satisfaction. Fourth, the trust in the relationship between emotional leadership and job satisfaction was found that the partial mediating effect. Especially, in the case of the business of hospitality, human services as well as material resources become its keynote, and we can safely say that the degree of dependence toward human resources is very high. Accordingly, the leaders should display their leadership on the basis of abundant emotional and intellectual faculties so that they can grasp, understand and admit the diverse views of value and emotion of the organization constituents and that they can form emotional leadership. On the basis of the analysis results of the verification of hypotheses, some suggestions and uppermost limit of this study have been presented for further study.

• The Journal of the Korea Contents Association
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• v.9 no.6
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• pp.289-299
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• 2009

This study set out to analyze the perceptions of investigative police officers and division police officers regarding Police Investigation Specialization, which had been in effect for four years, identify the problems, and search for alternative policies. The results led to the following alternative policies; first, the communication among the members should be facilitated by trading the jobs between investigative policemen and division members in certain percentage regularly, integrating job education and special work, and developing diverse support programs for detective activities to provide them with opportunities to experience and understand investigation. The second suggestion concerns the investigation members' morale. There should be a range of measures to boost their moral such as allocating separate budget and personnel to support the investigation department and the treatment of major criminal and civil cases, giving each investigation team an office and investigation room to improve their working environment, readjusting the promotion ratio of Police Investigation Specialization to introduce a promotion system proper for each investigation's characteristics. The third suggestion is to secure job efficiency. It's required to reinforce the current short-term specialized education program to bring up practical and professional investigators, open the certification exam of professional investigators to all members so that every policeman can have their abilities recognized and approved as long as they have the demanded capabilities, and create a system of shedding off the members idle at work by reflecting low performance records when evaluating the members to decide who to dismiss from Police Investigation Specialization. And finally, it's important to divide duties rationally. The rationality of duties division can be guaranteed by setting the guidelines for direct handling for the team leader to help him devote himself to his duties, defining objective criteria of measuring investigation workload, and creating devoted systems and teams for simple and small accidents so that experienced investigators can deal with high-profile cases.

• The Journal of Art Theory & Practice
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• no.3
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• pp.67-84
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• 2005

Since the evaluation of its intellectual activities and abilities is done by curator's capabilities, planning exhibition is very important as the final result achieved by their own knowledge, information, and research. ARPA(Advanced Research Project on Arts) is suggested as the system which enables curators responding simultaneously to the society in the times, based on its special characteristics. If this system settles well, which means that the curators at NMCA(National Museum of Contemporary Art, Korea) play their roles as the professionals in each of their fields, the goal of consolidating the status of museum as the representative national museum, and building up competent department of curators, will be achieved at the same time. To clarify above, the curators set up the various assignments of research about the types of arts such as painting, Korean painting, sculpture, installation, new-media, design, craft, photogarphy, architecture, etc. And they establish the art objects classified by the regions, such as the Northern American, Southern American, European, Asian, and other Third World countries. They elaborate art objects more on the history, the work, the artist, and the issue of contemporary art. Furthermore, when the curators devote deeper study to those research subjects, they can have the opportunities to design an exhibition upon the research. Today, the museum of art is 'The Place for Communication and Encounter', it is regarded important to share the aesthetical, creative values with current artists, and to understand mutually with the spectators. It is needed to improve the curator's work, in order to meet the demands of the times and even to advance. Because the form of 'exhibition' is the tool that reveals the identity NMCA aiming at, the motivation, the development, and the realization should be leaded by the curators, who are the mainstream of the museum. ARPA is a system for identifying the exhibition like mentioned above. The main purpose of this system is to produce synergy effect, having the researching, collecting work in liaison with planning exhibition. ARPA will be able to improve the quality of exhibition through the way of developing the exhibition, passing through the stable process in the long run. So far, I have referred to a new paradigm of the exhibition design at NMCA via ARPA. Yet, there still remain missions in reality, such as analyzing the previous exhibition and reshuffling personnel and system, which should be done. When these matters settled, these plans would be suggested practically. At this point, it is the most significant that NMCA is attempting to let others aware of the importance of exhibition planning based on research. when the ARPA and exhibition planning is conjoined together successfully, the competent exhibition will be achieved, which can offer a meaningful exhibition to the art world, strengthen infra structure thru exchanging with public museum in the region, and eventually, establish a network with museum in foreign countries.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.747-755
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• 2001

This study was analyzed the destination image and tests of image value of forest region festival by segmenting the market. A field survey was conducted during the Acasia-Honey Festival days in Chilgok, the famous acasia-honey products place, from May 12-15, 2001. In this study, 20 image items on five-point Likert scale were examined through factor analysis using a sample of 394 visitors. Four factors were identified as follows : environment, behavior-facilities, festival programs, and products. The author observed if there were statistically significant differences of destination images between the first-time and the repeat visitors, between residents and non-residents, and between purchasers and non-purchasers of acasia-honey products. The results indicated that repeat visitors and residents group had a more positive image of behavior factor such as hospitality and information for festival. And, the author found that purchasers of acasia-honey products had more positive image of product as well as environment factor such as special atmosphere, nostalgia, natural attractions, local culture, and novelty. For these results, it is possible to conclude that local government must effectively provide the festival visitors with well-defined information such as festival contents and schedule, also, develop the programs involved unique attributes of forest region festival to improve festival image.