• Journal of Adhesion and Interface
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• v.16 no.3
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• pp.101-107
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• 2015

Epoxy resin toughening agents such as core/shell nanoparticles, CTBN epoxy, polyester polyols, and polyurethane have been widely used in order to compensate for the brittleness and improve the impact resistance of the epoxy resin. In this work, a few tougheners mentioned above were individually added into adhesive compositions to observe the effects of physical and mechanical properties. Both flexural strength and flexural modulus were measured with UTM while impact strength was analyzed with Izod impact tester. The obtained results showed that the addition of toughening agents afforded positive performance in terms of flexibility and impact resistance of the cured epoxy resin. Furthermore, DMA experiments suggested that the trends of storage modulus data of each epoxy resin composition coincided with the trends of flexural modulus data. FE-SEM images showed that toughening agents formed circled-shape particles when it was cured in epoxy resin composition at high temperature by phase separation. The existence of particles in the cured samples explains why epoxy resin with toughener has higher impact resistance.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2002.10a
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• pp.18-25
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• 2002

The pikromycin biosynthetic system in Streptomyces venezuleae is unique for its ability to produce two groups of antibiotics that include the 12-membered ring macrolides methymycin and neomethymycin, and the 14-membered ring macrolides narbomycin and pikromycin. The metabolic pathway also contains two post polyketide-modification enzymes, a glycosyltransferase and P450 hydroxylase that have unusually broad substrate specificities. In order to explore further the substrate flexibility of these enzymes a series of hybrid polyketide synthases were constructed and their metabolic products characterized. The plasmid-based replacement of the multifunctional protein subunits of the pikromycin PKS in S. venezuelae by the corresponding subunits from heterologous modular PKSs resulted in recombinant strains that produce both 12- and 14-membered ring macrolactones with predicted structural alterations. In all cases, novel macrolactones were produced and further modified by the DesVII glycosyltransferase and PikC hydroxylase leading to biologically active macrolide structures. These results demonstrate that hybrid PKSs in S. venezuelae can produce a multiplicity of new macrolactones that are modified further by the highly flexible DesVII glycosyltransferase and PikC hydroxylase tailoring enzymes. This work demonstrates the unique capacity of the S. venezuelae pikromycin pathway to expand the toolbox of combinatorial biosynthesis and to accelerate the creation of novel biologically active natural products. The polyketide backbone of rifamycin B is assembled through successive condensation and ${\beta}$-carbonyl processing of the extender units by the modular rifamycin PKS. The eighth module, in the RifD protein, contains nonfunctional DH domain and functional KR domain, which specify the reduction of the ${\beta}$-carbonyl group resulting in the C-21 bydroxyl of rifamycin B. A four amino acid substitution and one amino acid deletion were introduced in the putative NADPH binding motif in the proposed KR domain encoded by rifD. This strategy of mutation was based on the amino acid sequences of the corresponding motif of the KR domain of module 3 in the RifA protein, which is believed dysfunctional, so as to introduce a minimum alteration and retain the reading frame intact, yet ensure loss of function. The resulting strain produces linear polyketides, from tetraketide to octaketide, which are also produced by a rifD disrupted mutant as a consequence of premature termination of polyketide assembly. Much of the structural diversity within the polyketide superfamily of natural products is due to the ability of PKSs to vary the reduction level of every other alternate carbon atom in the backbone. Thus, the ability to introduce heterologous reductive segments such as ketoreductase (KR), dehydratase (DH), and enoylreductase (ER) into modules that naturally lack these activities would increase the power of the combinatorial biosynthetic toolbox. The dehydratase domain of module 7 of the rifamycin PKS, which is predicted to be nonfunctional in view of the sequence of the apparent active site, was replaced with its functional homolog from module 7 of rapamycin-producing polyketide synthase. The resulting mutant strain behaved like a rifC disrupted mutant, i.e., it accumulated the heptaketide intermediate and its precursors. This result points out a major difficulty we have encountered with all the Amycolatopsis mediterranei strain containing hybrid polyketide synthases: all the engineered strains prepared so far accumulate a plethora of products derived from the polyketide chain assembly intermediates as major products instead of just analogs of rifamycin B or its ansamycin precursors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.715-727
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• 2020

For the empirical analysis in this study, 335 cabin crews from large airline companies and budget airlines were interviewed using self-reporting questionnaires. The data was analyzed using the SPSS 23.0 and AMOS 23.0. First, of the organizational culture types, the relationship-oriented culture, hierarchy-oriented culture, and task-oriented culture were found to have negative impacts on job stress. Second, the innovation-oriented organizational culture, relationship-oriented culture, and hierarchy-oriented culture were found to have positive impacts on empowerment. Third, empowerment was found to have a negative impact on job stress. Fourth, as for the mediating effect of empowerment, the innovation-oriented culture, relationship-oriented culture, hierarchy-oriented culture, and task-oriented culture were verified to be all significantly mediated by empowerment in their relationship with job stress. As a result, it was shown that cabin crews of airline companies found their work more fun, interesting, and valuable in an organizational structure that was more oriented toward flexibility, rather than the hierarchical, task-oriented cultures that are more focused on control and order. It was also found that empowerment was a mediating factor in the relationship between organizational culture and job stress.

• The Journal of the Korea Contents Association
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• v.20 no.9
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• pp.296-307
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• 2020

Compared to the quantitative increase in women's workforce, women's status in the organization remains poor. When it needs diverse perspectives and flexibility cope with the environment, it is an urgent challenge for companies to manage women in organizations. In this study, it is explored the internal factors of the organization that allow women managers to be more immersed in the organization. While previous researches have focused mainly on employment equality policies, this study expands the scope of existing research by considering the organization's internal support factors, such as mentoring, education and training, and organizational atmosphere. The female manager panel data showed that mentoring, education and training, and organizational climate all increase the leading influence of female. This leading influence affects organizational commitment and mediated between organizational internal factors and organizational commitment. In other words, it has been found that it is important for female managers to take the initiative in their position as well as the internal support of companies for female managers to immerse themselves in the organization. This study could contribute to solving the dilemma of the use of women's workforce by companies that fail to recover all investment costs such as recruitment, education, training, and compensation of excellent women's workforce.

• Korean Journal of Childcare and Education
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• v.10 no.5
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• pp.229-248
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• 2014

The purpose of this study is to draw guidelines on how to select traditional games that would efficiently help and develop multiple intelligences in children. Guidelines standard of section inquiries were prepared through a Delphi survey targeting twenty experts in early childhood education and traditional games. As a result, linguistic intelligence questions regarding writing, listening, speaking and vocabulary acquisition were selected. logical-mathematical intelligence questions regarding strategy, counting, patterns, hypothesis, verification, and comparing, contrasting, calculating ability were selected. Spatial intelligence questions regarding drawing, coloring, representation activities, operating and creating were selected, physical performance intelligence questions regarding global muscles, eye-hand coordination, flexibility, accommodation force, balance, agility and muscular strength were selected. Musical intelligence included questions about singing, and playing musical instruments. Interpersonal intelligence included perspective-taking, role-sharing, cooperation and discussion. For intrapersonal intelligence questions regarding personal significance-ties, planning-decision making, emotional expression and problem solving were selected. Finally, in relation to naturalist intelligence, questions regarding living organisms, inanimate objects and seasons were selected. In addition, traditional games were analyzed based on the finalized guidelines, and the results showed that each of the traditional games would not only work with one intelligence at a time but with other different intelligence as well. In the light of that, the study confirmed the validity of the guidelines on how to select traditional games that would develop multiple intelligences in children.

• Journal of The Korean Digital Architecture Interior Association
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• v.2 no.1
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• pp.9-15
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• 2002

As architectural forms tend to be large-scaled, high-storied and complicated, use of computer for processing design information has been generalized. However, CAD use in the process of developing architectural design has been neglected greatly in the educational field of architectural field due to the surging of recognition that it may limit the essential property of architectural design. It may be resulted from the limitation of CAD system, that is, it is because of tardy speed of application development for the related areas with the lack of simplicity and clarity of flexibility to be secured on the drawing and user interface. Recent CAD systems, however, overcome such a limitation, convert into object-based design from entity-based drawing, drafting and modeling for implementing design concept of architects and it connects with internet linked to superspeed information communication network and changes process and stream of architectural design. Therefore, this study deals with utility of object based CAD system with products of Autodesk Co. and consequently obtain the following conclusions. First, it expands architect's design areas by supporting cooperative design system based on model-based architectural design and internet. Second, it reduces consumption of personal and material resources and time in the process of drawing production for improving architectural design works. Third, it can reduce the frequent design changes by improving understanding of architectural space with visualization of immediate 3D information, escaping from traditional methods to deliver design information to building owner through 2D drawing or model and perspective drawing requiring much cost and time. Fourth, it keeps exactness without omission or duplication of design information and generate and renew information of all related drawings on a drawing. Fifth, it is possible to change difficult and boring architectural design work into a pleasure owing to immediate modeling and drawing of design idea. In addition, digital drawing generated by using object-based CAD system can playa role of establishing Urban Information System to be used for protecting from building in disaster and urban disasters in connection with GIS numerical map and be used for reference of all kinds of information required fro post-management of buildings. However, what is more important is that surplus time from introduction of object-based CAD system should be used for consideration to be recognized as a good space and building built as a product of this project for comfort to urban people.

• Journal of Korean Academy of Nursing
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• v.24 no.4
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• pp.568-583
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• 1994

In the changing social and economic conditions, reorientation of the health care system is a process of rearranging health care resources keeping in mind the appropriativeness, relevancy, and efficacy of health care programs. Also it has been recognized recently that the CHP program is in need of review for the same reasons, that is to say, the ease in which health care facilities are available, the high rate of coverage with insurance and the development of an effective transportation system. Therefore there is a social inclination to think that there are no remote areas and to question the roles of public health facilities, health centers, health sub centers and CHP posts. This paper was done to review problems and to propose new directions for the CHP system. The findings of this study are as follows ; 1) It is necessary that primary health care should be simplified into three parts, medical treatment, preventive care services and the organization of administration and logistics. Also each department should be supplemented with the appropriate professional personnel in order to develop a task oriented system. The reorientation of the CHP system should be managed in keeping with that of other public health care systems. Therefore it is necessary to look at the CHP system problems as one aspect of the reorientation process of public health care systems, and to work to find new ways to address these problems. 2) The location of the CHP post should be decided by the needs of the community in both the medical and preventive areas. If the people have a minimum need, the location of the CHP post should be altered and the existing roles of the CHP should be modified to allow for flexibility according to the community needs. 3) Use of the problem solving method in regular team meetings will prove to be as efficient as continuing education programs in improving job competancy. 4) The supervision of CHP's activities should be made by the same type professional personnel, that is, senior CHPs or charge nurses in the public health center at the county level. 5) The operational expensies of CHP post should be supported by the administrative department of the public health center and should create working conditions that will allow the CHP to concentrate on community health service programs. 6) The organizations for community participation, working committees, community health workers and a number of the local assembly, should be activated to provide for participation in finding solutions to health related problems in the com-munity.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.4
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• pp.69-74
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• 2010

A new package substrate for dynamic random access memory(DRAM) devices has been developed using selective aluminum anodization. Unlike the conventional substrate structure commonly made by laminating epoxy-based core and copper clad, this substrate consists of bottom aluminum, middle anodic aluminum oxide and top copper. Anodization process on the aluminum substrate provides thick aluminum oxide used as a dielectric layer in the package substrate. Placing copper traces on the anodic aluminum oxide layer, the resulting two-layer metal structure is completed in the package substrate. Selective anodization process makes it possible to construct a fully filled via structure. Also, putting vias directly in the bonding pads and the ball pads in the substrate design, via in pad structure is applied in this work. These arrangement of via in pad and two-layer metal structure make routing easier and thus provide more design flexibility. In a substrate design, all signal lines are routed based on the transmission line scheme of finite-width coplanar waveguide or microstrip with a characteristic impedance of about $50{\Omega}$ for better signal transmission. The property and performance of anodic alumina based package substrate such as layer structure, design method, fabrication process and measurement characteristics are investigated in detail.

• Korean Journal of Social Welfare
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• v.57 no.2
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• pp.41-70
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• 2005

The object of the study is to examine the change of social-economic structure and poverty-shape to escape poverty. In Korea, the working poor have been increased by flexibility and division of labor market since the economic crisis in 1997, and are faced with hard conditions due to the vulnerable welfare system. Especially the workers who engage in irregular jobs were increased by restructure of labor market. Besides they are in unstable employment terms such as low payment, low-skill and exclusion from welfare-benefit. Many small independent businessmen are also in danger of poverty for enterprises trend to move abroad by globalization. Poverty policy in our country was focused on the absolute poor class that has relation with old age, unemployment, disable, disease etc, so they were the object of welfare policy. The poverties, however, are increasing rapidly after the economic crisis, and they work so hard but are still poor, that is, participation in labor market doesn't become an element to escape poverty. Thus the emergence of new poverties whose core consists of the working poor becomes to need new poverty policy. The study is to survey change of their economic conditions, their welfare conditions, their experiences and responses of social dangers after the economic crisis, then to explore the policy to escape poverty. As the result of the study, it shows that the working poor experienced many kinds of social dangers like unemployment, decrease of income etc. In their welfare conditions as their responses to the social dangers, the benefit of social insurance, enterprise welfare like legal retirement pay and paid leave and private welfare such as private pension and insurance are low. The working poor are faced with social dangers, moreover, they don't have skill or education for adapting themselves to information society. The study says that it needs variable policies for the working poor to escape poverty, and suggests payment & tax policies as stable income policy, occupational discipline and skill-education for promoting the quality of employment, moreover, social insurance as expansion of social welfare policy and housing & education policies whose objects are the working poor.

• Journal of Korean Public Health Nursing
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• v.16 no.1
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• pp.95-104
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• 2002

Purpose : This study was conducted to investigate the extent to which the professional self concept between the psychiatric mental health nurse practitioner (PMHNP) and general nurse in psychiatric ward was comparable. The results were expected to provide basic data for developing the construct of professional self concept and making awareness of the importance of the program increasing professional self concept. Method : The subjects of this study were 227 PMHNP and 436 general nurse in psychiatric ward. The instruments used for this study were PSCNI by Arthur (1990), PSI by Heppner and Peterson(1982) and the index of work satisfaction by Slavitt et al.(1978). With the aid of the SAS, t-test. two-way ANOVA and stepwise multiple regression were conducted. Result : 1. The average item score of PSCNI of PMHNP was $2.82\pm0.27$. and that of general nurse was $2.66\pm0.27$. Statistically significant difference between two groups was found(p=0.0000) 2. There was statistically significant difference between two groups in the score of professional practice(p=0.0000), satisfaction(p=0.0024), leadersbip(p=0.0000) , flexibility(p=0.0000) and skill (p=0.0000). 3. Statistically significant differences between the two groups were observed in terms of age(p=0.0003), marital status(p=0.0001). education(p=0.0005), religion(p=-.0144), motive (P=-.0001), length of service as a nurse(p=0.0121), the length of service in psychiatric unit(p=0.0143). However there were no significant interaction effect with group and age, marital state. education, religion, motive, length of service as a nurse, length of service in psychiatric unit. 4. Job satisfaction (JS) and problem solving inventory score(PS) were found to be the highest factor predicting the professional self concept between the PMHNP and general nurse. JS and PS accounted for $43.4\%$ in the professional self concept of PMHNP, whereas PS, JS, age and religion accounted for $53\%$ in the professional self concept of general nurse in psychiatric ward. In conclusion, this study suggested that we need to develop programs and polices to increase the professional self concept of nurse, particularly of psychiatric mental health nurse practitioners.