• Proceedings of the KWS Conference
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• 2002.10a
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• pp.235-243
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• 2002

Ni-base superalloys are used extensively in industry, both in aeroengines and land based turbines. About 60% by weight of most modern gas turbine engine structural components are made of Ni-base superalloys. To satisfy practical demands, the efficiency of gas turbine engines has been steadily and systematically increased by design modifications to handle higher turbine inlet or firing temperatures. However, the increase in operating temperatures has lead to a decrease in the life of components and increase in costs of replacement. Moreover, around 80% of the large frame size industrial/utility gas turbines operating in the world today were installed in the mid-sixties to early seventies and are now 25 to 30 years old. Consequently, there are greater opportunities now to repair and refurbish the older models. Basically, there are two major factors influencing the weldability of the cast alloys: strain-age cracking and liquation cracking. Susceptibility to strain-age cracking is due to the total Ti plus AI content of the alloy; Liquation cracking is due either to the presence of low melting constituents or constitutional liquation of constituents. Though Rene 41 superalloy has 4.5wt.% total Ti and Al content and falls just below the safe limit proposed by Prager et al., controlled grain size and special heat treatments are needed to obtain crack-free welds. Varying heat treatments and filler materials were used in a laboratory study, then the actual welding of service parts was carried out to verity the possibility of crack-tree weld of components fabricated from Rene 41 superalloy. The microstructural observations indicated that there were two kinds of carbides in the FCC matrix. MC carbides were located along the grain boundaries, while M$_{23}$C$_{6}$ carbide was located both inter and intra granularly. Two kinds of filler materials, Rene 41 and Hastelloy X were used to gas tungsten arc weld a patch into the sheet metal, along with varying pre-weld heat treatments. The microstructure, hardness and tensile tests were determined. The service distressed parts were categorized into three classes: with large cracks, with medium cracks and with small or no visible cracks. No significant difference in microstructure among the specimens was observed. Specimens were cut from the corner and the straight edge of the patch repair, away from the corner. The only cracks present were found to be associated with inadequate surface preparation to remove oxidation. Guidelines for oxide removal and the welding procedures developed in the research enabled crack-free welds to be produced.d.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.3
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• pp.92-106
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• 2008

The purpose of this study is to identify land use types and to develop and evaluate biotope maps for Gangseo-Gu (ward) in Busan Metropolitan City, South Korea, using the Degree of Hemeroby. Hemeroby is a measurement concept or tool to assess the magnitude of human impact on ecosystems. Gangseo-Gu is the second largest Gu in Busan and is under strong development pressure. Before the field survey, biotopes were pre-classified based on digital maps, aerial photos and high-resolution satellite images. The method employed in biotope survey and mapping was adopted from the modified method used in Seoul, which carried out the first biotope mapping in Korea in 2000. In the field survey, a comprehensive biotope mapping method was used. The results showed that the total surface area of biotopes in Gangseo-gu was $172,620,207m^2$(42,655 acres) and there were 29 biotope types with 13,631 polygons. The ratio of urban or built-up area 22.6% and the remaining areas were forest and open spaces, of which 22.6% were actual forest areas and 35.6% were paddy fields and other field areas. The Hemeroby Index of Gangseo-gu was 54.7, which suggests that Gangseo-gu has not yet been developed extensively and needs a long-term conservation and coordinated development plan.

• Korean Journal of Social Welfare
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• v.62 no.3
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• pp.219-245
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• 2010

The objective of this study is to identify the community living experiences of married immigrant women in rural areas. For this purpose, we conducted qualitative research by sampling 14 married immigrant women who had lived in Korea for over three years by having in depth interviews with them. This study employed the grounded theory method suggested by Strauss and Corbin(1998). When raw data from in depth interviews with the participants were processed by open coding through the continuous comparison method with theoretical sensitivity, a total of 13 categories, 27 sub.categories, and 71 concepts were extracted. In case of axial coding, according to the results of analyzing through the paradigm procedure, the causal conditions for the community living experiences of married immigrant women in rural areas were 'Uncertain start' and 'Confront practical problems,' and the central phenomenon was 'Search for existence to participate in community activities.' Contextual conditions affecting the phenomenon was 'Regret international marriage,' 'Experience conflicts,' and 'Look with negative prejudices,' 'Overcome the actual' and action/interaction strategies were 'Look for a breakthrough of life' and 'Manage to acceptance.' Intervening conditions for promoting or suppressing the action/interaction strategies for the central phenomenon were 'Social support system' and 'local limitations,' and as a result, the community living experiences of married immigrant women in rural areas appeared to 'Prepare the future,' 'Hope continuous social activities,' and 'Expect public support systems.'

• Journal of the Korea Institute of Building Construction
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• v.13 no.6
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• pp.585-593
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• 2013

For a successful construction project, systematic and objective decision-making is a prerequisite from the planning and designing stages. However, previous LCC analysis methods have focused only on simple cost savings and the accompanying economic efficacy while missing the environmental aspects of a structure. Although recently, a new approach of integrated $CO_2$ analysis has been introduced, which is more advanced than the existing simple LCC methods, it is difficult to collect all of the data necessary for each evaluation item since the product-specific cost is not presented under the LCC. In this research, cost evaluation items were selected by relatively high weights and items with heavy influence over a decision-making process in order to suggest an LCC-LCA integrated analysis model that is useful in comprehensively assessing the economic cost and environmental cost throughout the whole life cycle of a structure. The developed LCC-LCA integrated analysis model was applied to actual practices and compared with previous methods to test the model's effectiveness.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.291-297
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• 2019

Since Metcalfa pruinosa was first reported in Koera, it has continually caused damage to sweet persimmon orchard in southern part of Korea. Metcafa pruinosa exist not only in farmland but also in forest areas, and are difficult to control due to the influx of individuals from near forest. M. pruinosa has been occurred in orchard and its surroundings because of various host range. Thus, it has been difficult to decide spatial range and control time for efficient management. In this study, occurrence and dispersal pattern of M. pruinosa in persimmon orchard were surveyed using clear sticky traps, and spatial patterns were analyzed with SADIE(Spatial Analysis by Distance IndicEs), based on location information at sticky traps. Spatial association between survey time was also analyzed to identify when the spatial pattern changed. In sweet persimmon orchard, M. pruinosa mainly dispersed in mid to late May, when the first instar hatches, and in August, emerging season of adult. The first instar nymphs hatched in mid-May were randomly distributed in orchard, but distribution was changed to aggregative pattern after dispersed surroundings of orchard. Adults showed random distribution pattern after immigration to orchard again. These tendency was also observed in density change at orchard and its surroundings, and matched to actual density of M. pruinosa in sweet persimmon trees.

• Journal of Korean Academy of Nursing
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• v.30 no.1
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• pp.84-97
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• 2000

The Necessity and Purpose of the Study Recently the number of patients with chronic diseases and the aged patients is increasing steadily. Furthermore, due to the expansion of health insurance system, the number of patients hospitalized in the general hospital is increasing at a surprising speed. However, hospitals urge the early discharge of the patients for the efficiencies of hospital administration, and therefore, the number of patients who must be taken care of in their home is also increasing. Homecare nursing is one of the health care service for the patients at home who require continual attention and care, and now increasing attentions are given to it as one of the professional nursing fields. However, it was almost impossible to find a study on the actual experiences of the homecare nurses written by their own language in Korea, that it also posed a great difficulty in understanding their diverse experience. Considering these situation, this study will help understanding of them, and provide the fundamental data on their experiences for making policies to develop homecare nursing. Methods of Research Phenomenological research method was employed to analyze the lived experiences of homecare nurses fundamentally. Data collection Data were collected from August 1998 to December 1998 from ten homecare nurses who worked for patients under the homecare nursing setting as model cases designated by Seoul Nurses Association and who agreed to the purpose of this study after listening to and understanding the explanation completely. The in-depth interview was carried at the time which was convenient both for the researcher and participants for one or two hours, and recovered with the approval participants. The first interview covered diverse and broad areas like the situation of homecare nursing, and their feelings and thoughts over it, and in the second and third interviews, more specific questions are asked. Data Analysis For the phenomenological analysis, contents analysis was employed. The data collected from the participants were analyzed into the following procedures according to Van Manen 's phenomenological analysis. 1) Reserve the preconception of the researcher by restricting it inside parenthesis. 2) Make a thorough observation of the lived experiences by insight process. 3) Analyze the contents (Find out the repetitive factors) 4) Interpret the essence found. 5) State the meaning of the interpretation. Results and discussion 1. Fear and expectation for the first visit. (unfamiliarity, awkwardness, anxiety, shivering) 2. Mingle with the family (feeling friendly with the family, becoming like a family member) 3. Being proud of her own know-how (learning the know-how, organizing alternatives, building up confidence) 4. Pity for the poor. (criticizing the current government, feeling ashamed, feeling anger) 5. Difficulty of constructing cooperative system with physicians (strenuousness, frustration) 6. Helplessness due to the lack of support system (difficulty to get supplies, annoyance, embarrassment by institutional restraints) 7. Anxiousness for heavy traffic and parking (annoyance, hastiness) 8. Ethical conflicts (pity for the patients and family, skepticism about lengthening life maintenance) 9. Burden for the possible accident (pressure, anxiety, conflict, physical exhaustion) 10. Establishment of identity as a professional (fulfillment, worth, joy) 11. Being distressed at other's ignorance

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.239-244
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• 2008

We lead a life in our community, beginning a new relationship with a stranger or maintaining or stopping existing relationships. Relationships with others are sustained through social activities based on communication. Generally speaking, by exchanging feelings and information through communication, relationships are formed and continued, and strengthened through active communication As a result of the development of technologies and information technology over the recent 10 years, a mobile phone has stood as a communication channel, and now it has become such a universal, and highly intimate and important means of communication that almost all the Koreans use more often than wired phones. Today, people have their communication channel available for others, by using a mobile phone at any time and anywhere. Like this, mobile phones have been playing a key role in helping people maintain, repair and strengthen their personal relationship, but from the perspective of personal relationship management, they still remain as an aid to help communication, failing to provide a positive help for actual relationship management. This study was designed to provide services supporting user's personal relationship management, focusing on the use of mobile phones as a major tool of communication, aiming to enable users to understand current state of their relationship and make relationship management efforts, or communication behaviors, by informing who needs communication, on the basis of data on mobile phone calls. To this end, the study established a method to extract intimacy between users and callers and develop a prototype of services supporting personal relationship management, using relationship characteristics in terms of mobile communication.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.10
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• pp.109-117
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• 2014

In navigation route planning systems using A* algorithms, the cardinality of an Open list, which is a list of candidate nodes through which a terminal node can be accessed, increases as the path length increases. In this paper, a method of alternately utilizing the Dijkstra's algorithm and the A* algorithm to reduce the cardinality of the Open list is investigated. In particular, by employing a depth parameter, named Level, the two algorithms are alternately performed depending on the Level's value. Using the hybrid searching approach, the Open list constructed in the Dijkstra's algorithm is transferred into the Open list of the A* algorithm, and consequently, the unconstricted increase of the cardinality of the Open list of the former algorithm can be avoided and controlled appropriately. In addition, an optimal or nearly optimal path similar to the Dijkstra's route, but not available in the A* algorithm, can be found. The experimental results, obtained with synthetic and real-life benchmark data, demonstrate that the computational cost, measured with the number of nodes to be compared, was remarkably reduced compared to the traditional searching algorithms, while maintaining the similar distance to those of the latter algorithms. Here, the values of Level were empirically selected. Thus, a study on finding the optimal Level values, while taking into consideration the actual road conditions remains open.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.716-724
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• 2014

This study was conducted as a comparative analysis, using the SPSS 17.0 program for a survey conducted from March to July 2013, on the level of perception and preference factors of Koreans and Americans residing in Virginia, USA(89 male and female adults of 20 years of age or above). For the information on the degree of obesity, a survey was used and the subjects provided with their heights and weights. The researcher used this data to calculated their BMI and distinguished the degrees of obesity. For the BMI, the obesity diagnosis of Korean Society for the Study of Obesity was used for Koreans, and the WHO's obesity diagnosis on adults were employed for Americans. First, regarding the Korean participants, the level of obesity appeared in the order of normal (79.6%), overweight (14.3%), and underweight (6.1%). Also, the level of perceptions of their health conditions appeared in the order of average (51.7%) and good (34.7%). No one perceived their health to be in poor condition. Meanwhile, for the American participants, the order was as follows: overweight at about 45%, normal weight at about 35%, obesity at about 12.5%, and underweight at about 7.5%. In terms of the level of perception of health during ordinary times, about 55% of the American participants answered that they are in good health. Therefore, the Americans were found to perceive their health to be in relatively better condition than the Koreans residing in the USA. Also, concerning the level of interest in health while eating food at ordinary times, the American participants were discovered to be more interested (about 62.5%) than the Korean participants. The research on their preference for salty taste was conducted as a survey, and the subjects were asked to choose an item according to their subjective feeling. Regarding the preference for salty taste, both Koreans and Americans residing in the USA responded as moderate. However, a higher proportion of Americans than Koreans responded to favor salty taste. Concerning the reason for their preference for salty taste, Koreans responded with various reasons whereas Americans mostly responded that it is because they eat salty food frequently. For any changes in dietary behavior related to eating salty food, both Korean and American respondents thought that the amount of their daily intake of salt is appropriate and that they consider taste as most important in selecting a snack. Based on the above data, the results of this research indicate a need for actual improvement in the diet with regard to salty food along with diverse policies for promoting life with a low salt diet in future.

• Fire Science and Engineering
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• v.15 no.1
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• pp.127-138
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• 2001

I. introduction. A government goal at the present is established to make a welfare nation and to keep people's safe living, but it is criticised that when a large-scale disaster happens, the authority concerned could not deal with it, causing many people injured and material damage. Moreover, in these days, cities have many risk factors. extremely large and intelligent building, industrial facilities and underground equipment have many risk themselves along with scientific progress. The cope with disaster effectively, government must have efficient organization, skillful personnel, tool, facilities and so on. To reduce the damages, what's the most effective government organization\ulcorner II. Government organization for managing disaster In a few decades, a large-sized accidents broke out in korea, for example, collapse of Sampoong department store, break of Sungso bridge, explosion of Daegu city gas, gas explosion accident at Ahyon-dong etc. but government has not any adequate disaster response organization. Especially, after collapse of Sampoong department store broke out, Disaster Management Act is enacted to solve the past problem. According to Disaster management Act, disaster is limited in manmaid disaster. Therefore, in this thesis, disaster management is inspected theoretically, organization of disaster management for pattern of disaster, and role, duty of government organization, emergency relief organization system and actual conditions are analyzed. there are some problems. there are trials and errors. the government has changed the disaster management organization by the disaster management law. the organization consists of central and local government. but both of government do not work together harmoniously. in thesis, I would like to introduce the advanced nations disaster management organization, and study our central, local government organization. III. Conclusion Change and development of the government disaster management organization is the goal of this thesis. we have to increase public service in response and manage disaster. protecting civilian's life from the disaster is very important responsibility of government. there would be better way of government disaster management organization.