• Journal of Korean society of Dental Hygiene
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• v.15 no.6
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• pp.1033-1041
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• 2015

Objectives: The purpose of the study is to find out the effect of part-time employment experience on adaptation to university life in dental hygiene students. Methods: A self-reported questionnaire was completed by 288 dental hygiene students in Seoul and Gyeonggido from September to October, 2014. The questionnaire consisted of general characteristics of the subjects(5 items), part-time employment experience(6 items), and adaptation to university life(53 items). The instrument for adaptation to university life was adapted from Baker and Sirky and modified by Kwon. Likert 5 point scale adaptation included personal emotion adaptation, academic adaptation, social adaptation, and university environment adaptation. Cronbach's ${\alpha}$ was 0.80 in the study. Results: The adaptation to university life was 3.0 points. The higher the economic level was, the higher the personal emotional adaptation(p<0.001) and academic adaptation were(p<0.05). The adaptation to university life was positively influenced by tuition support by parents and part-time employment(p<0.05). The part-time employment was significantly helpful to future job selection, social adaptation, and university environment adaptation(p<0.001). Economic stability and advantage of future job selection had a positive influence on the adaptation to university life. So the adaptation to university life was proportional to younger age, economic stability, and advantage to future job selection. Conclusions: It is very important to give a positive motivation and stimulation, and a careful counseling to the students in part-time employment. In order to encourage the part-time employed students, major-related part-time job opening must be given.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.3
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• pp.128-133
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• 2018

Korean civil airworthiness requirements of powerplant system are regulated by KAS(Korean Airworthiness Standard) Part 23 and Part 33. These are equivalent to FAR Part 23, Part 33 of FAA, and CS-23 and CS-E of EASA. FAA and EASA rewrite the airworthiness requirements for small airplane. They changed current 'prescriptive regulation' to a 'performance-based regulation' which makes safety performance the objective. Powerplant requirements have also been changed extensively by this concept revolution. In accordance with this reorganization, we studied the new powerplant system requirements of FAR Part 23 and proposed ideal directions to rewrite the Korean Airworthiness Standard.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.3
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• pp.61-66
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• 2011

The integrity of the SG(Steam Generator) tubes has been challenged by numerous factors such as flaws, operation, atmosphere, inherently degraded materials, loose parts and even human errors. Of the factors, loose parts(or foreign materials) on the secondary side of the tubes can bring about volumetric defects and even leakage from the primary to the secondary side in a short period of time. More serious concerns about the loose parts are their unknown influx path and rapid growth rate of the defects affected by the loose parts. Therefore it is imperative to detect and characterize the foreign materials and the defects. As a part of the measures for loose part detection, TTS(Top of Tubesheet) MRPC(Motorized Rotating Pancake Coils) ECT has been carried out especially to the restricted high probability area of the loose part. However, in the presence of loose parts in the other areas, wide range loose part detection techniques are required. In this study, loose part standard tube was presented as a way to accurately detect and characterize loose part signals. And the SG tube ECT bobbin coil and MRPC ISI(In-service Inspection) data of domestic OPR-1000 and Westinghouse Model F(W_F) were reviewed and consequently, comprehensive loose part detection technique is derived especially by applying bobbin coil signals

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.3
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• pp.115-119
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• 2018

Defining and measuring non-rigid or flexible parts has been controversial in industry for many years. There are two primary areas of controversy. The first is agreeing on what exactly a non-rigid part is. The second is agreeing on how to define and measure a non-rigid part. The subject of non-rigid parts is further complicated by the brief coverage it receives in the national and international standards. This leaves each company to improvise or create its own rules for non-rigid parts. There are some who believe that Geometrical Dimensioning and Tolerancing (GD&T) should not be used on non-rigid parts. This is not true. The ASME Y14.5M standard applies to rigid parts as a default condition. However, there is no definition given for a rigid part. The term rigid part has been used in industry for so long that it has gained a definition by its general use. When most people in industry say rigid part, they are referring to a part doesn't move (deform or flex) when a force (including gravity) is applied. How much force is relative based on the part characteristics. In reality, all parts will deform (or flex) if enough force is applied. Using this logic, all parts would be considered non-rigid. However, we all know that this is not how parts are treated in industry. Although GD&T defaults to rigid parts, it should also be used on non-rigid parts with a few special techniques. Actually 50~60% of all products designed contain parts or features on parts that are non-rigid. Therefore, we try to suggest the definitions of rigid and non-rigid parts and method to measure non-rigid parts.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.6
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• pp.52-59
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• 2013

In this study, strength and durability are investigated using structural and vibration analyses on models 1 and 2 of a press in common use. Model 1 has a structure in which a punch is applied from the upper part to the lower part; however, model 2 a structure in which a punch is applied from the lower part to the upper part. Maximum displacements of models 1 and 2 are 0.018184 mm and 0.025498 mm, respectively. Maximum equivalent stresses of models 1 and 2 are 14.144 MPa and 18.58 MPa respectively. Maximum displacements are shown for the punches of both models; model 1 has less deformation than model 2. Model 1 has more durability than model 2, as determined by an investigation of the structural strength. Using natural frequency analysis, model 1 was found to have maximum deformation in the upper part of punch. Mode1 2 has its maximum deformation in the column part of the body and the upper part of the fixed pin. Using harmonic stress analysis, the maximum deformations were found on the punch part and column part of the body in the cases of models 1 and 2, respectively. As the maximum total deformation and equivalent stress in the case of model 2 are shown to become 40 times those values of model 1, the vibration durability of model 2 can be seen to be weaker than that of model 1.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.4
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• pp.307-314
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• 2012

IFC-based representation method of part library for superstructure module of modular steel bridge is proposed. The library is capable of efficiently offering and exchanging part information in process of manufacture, assembly, design, and construction of modular steel bridge. Entities, representing physical part information in IFC model, are matched semantically with parts of the superstructure module for representation of part information with IFC model. Either types of matched entities are applied in order to verify the role of each part, or new types are defined as a user-defined types. In addition, assembly system has been classified and defined into 4 levels of LoD(Level of Detail) to provide appropriate part information efficiently from the part library in each step of the process. Then, new property is defined for representing the LoD information with IFC Model. Finally, IFC-based test library of modular steel bridge is generated by applying the matched entities and entity types to the actual the superstructure module of modular steel bridge.

• The Journal of Korean Medical History
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• v.27 no.1
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• pp.87-112
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• 2014

Purpose : "The Part of Cold damage in Uihakipmun" is the collection of the books on Cold damage which follow the way of description focusing on symptoms before Ming dynasty. "The chapter of First symptom" in this part is the first chapter which described focusing on the symptoms in earnest. This research is to discover the reference books of "The chapter of First symptom" in detail. Methods : I compared the books presented in the reference list of "The Part of Cold damage in Uihakipmun" with the sentences of "The chapter of First symptom". Results & Conclusions : "The chapter of First symptom" referred to "Sanghanyukseo(傷寒六書)" and "Injaesanghanryuseo(仁齋傷寒類書)" mainly, and the rest were supplemented with other books like "Hwalinseo(活人書)". And the books which were not listed on the reference like "Sanghanmyeongriron(傷寒明理論)", "Yupyeonhwalinseogwaljijangdoron(類編活人書括指掌圖論)" were also referred in part. Among the reference list of "The Part of Cold damage in Uihakipmun", "Baekmun(百問)" doesn't indicate "Sanghanbaekmun(傷寒百問)" but "Sanghanbaekmunga(傷寒百問歌)". As for the history of the books on cold damage which described focusing on symptoms, "Injaesanghanryuseo" added new contents on the basis of "Hwalinseo" and after that, it had a large influence on "Sanghanyukseo" and "The Part of Cold damage in Uihakipmun". In case of 33.4% of the chapter of first symptom, the reference books were not found. It includes the part that the reference books were not found and also the part that Lee Cheon added his personal opinion. For this parts, the in-depth study is needed afterwards.

• Korean Journal of Labor Studies
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• v.17 no.1
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• pp.269-295
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• 2011

This paper is about the part-time work and related polices in Netherland, which increased the employment rate for the past 30 years with part-time job creation. Netherland has been successful in making part-time 'good' jobs. There were many factors which contributed to increaing part-time jobs such as market, institution, policies, and industrial relations. There was virtuous cycle between increase in the supply of female labor power and increase in the demand for part-time worker in the labor market. The policies were reinforced which protect part-time workers, introduced the incentive system which was favorable to part-time wokres, guaranteed the right to select working hours to workers. Particularly, the labor market, institutions and policies were created in the midst of the social dialogue. As the polder model has been persisted for almost 30 years, the switch to full-time work or long working-hour model would not be possible. As the poler model is a very specific model based on the Netherland's own social conditions, it is not easy to copy and transplant in other countries.

• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.304-308
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• 2021

Iris koreana (Iridaceae) is an endangered plant native to Korea. In order to develop an in vitro propagation method, we investigated the effect of 2,4-dichlorophenoxy acetic acid (2,4-D) and a-naphthalene acetic acid (NAA) on callus induction in different I. koreana tissues. In addition, we also investigated the effect of 2,4-D and Benzyl aminopurine (BA) treatments on adventitious shoot induction in viable calli and the effect of indole-3-butyric acid (IBA) on root formation in viable shoots. We found that callus production was highest with 1.0 mg/L NAA (94.4% cultured rhizome explants), and adding low concentrations of 2,4-D to BA containing media significantly increased the frequency of shoot primordial formation. The best rooting results were obtained with 1.0 mg/L IBA, on which 98% of regenerated shoots developed roots and produced an average of 7.4 roots within 45 days. This in vitro propagation protocol will be useful for conservation, as well as for mass propagation.

• Journal of Korean Home Economics Education Association
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• v.13 no.1
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• pp.73-91
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• 2001

The purpose of this study was to analyze the changes in home management part in the home economics textbooks for middle school from the 1st to the 7th curriculum period. The part of home management in the all of home economics textbooks published in every curriculum period was analyzed using several external criteria of textbook. The major findings of this study were as follows : 1. The part of home management was divided into even specific areas including 'definition and process of home management'. 'time management'. 'household labor/work management'. 'family financial management'.'purchasing'. and 'consumer protection'. 2. The part of home management has been included in the middle school home economics textbooks since the 1st curriculum period. The proportion of this part in the whole textbook varied with range from 5.1% to 31.8%. 3. The areas emphasized in the beginning of curriculum period were 'family financial management'and 'household labor/work management'. and 'utilization of family resource and environment management'were the areas emphasized in the later curriculum period. 4. The titles of the middle and small unit have begun to use recent words and have represented the including contents since the 4th curriculum period. 5. The numbers of illustrations. tables. pictures. and activities have increased since the 6th curriculum period. 6. Other unrelated areas such as computer and career preparation were included in the home management part in the 1st. 2nd. and 5th curriculum period.