• Tribology and Lubricants
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• v.4 no.2
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• pp.52-59
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• 1988

The purpose of this study is to establish a standard for proper selection of water soluble cutting fluids, such as Emulsion type, Semi-Synthetic type and synthetic type, by investigating cutting effects at the normal temperature(26$\circ$C) and cooling temperature(0$\circ$C) from the viewpoint of cooling and lubricant actions. This paper describes a relation among cutting force, surface roughness and cooled water soluble cutting fluids which are considered as effective restraints on Built up edge.

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.135-136
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• 2015

대용량 분산 발전원이 증가하면서 이러한 대용량 분산 발전을 효율적으로 운전하기 위한 많은 연구가 진행되고 있다. 본 논문에서는 멀티레벨 인버터 토폴로지 중 NPC와 T-type 인버터의 중성점 전압제어를 통해 두 개의 멀티레벨 인버터에서 발생하는 효율과 제어방식의 차이를 시뮬레이션하고 비교 분석하였다.

• Honam Mathematical Journal
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• v.45 no.2
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• pp.340-358
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• 2023

This article establishes an equality for the case of twice-differentiable convex functions with respect to the conformable fractional integrals. With the help of this identity, we prove sundry midpoint-type inequalities by twice-differentiable convex functions according to conformable fractional integrals. Several important inequalities are obtained by taking advantage of the convexity, the Hölder inequality, and the power mean inequality. Using the specific selection of our results, we obtain several new and well-known results in the literature.

• Journal of Korean Academy of Nursing
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• v.29 no.5
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• pp.1072-1086
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• 1999

This study has been attempted using the Q methodology to clarify leader type of nurse managers that head nurses and general nurses recognize, and to clarify its relative relation. Sixty-three statements were extracted through interviews with general and professional people interested in the subject of nurse leaders to extract the Q population. A total of 314 Q population was formed added with 251 questions extracted from related documents. Final 32 Q samples were selected by reorganization of 314 Q population after reexamining statements through inquiry of 1 professor of the nurse department, 2 students in course of nurse science masters degree and 2 students in course of doctoral degree. The P sample selection standard of this study were 25 nurses and 30 head nurses. Examination subjects themselves filled out 32 statements classified in a measure of 9 points from agreeable items to disagreeable items. Principal component factors were analyzed using the QUANL pc program after grading the contents of the P sample. Nurses recognizing subjective structure for leader behaviors of nurse manager were analyzed to be 3 factors: vision presentation type, self-capability consideration type, relationship consideration type, and head nurses recognizing subjective structure were analyzed to be 2 types: task pursuit leader type, and concord pursuit type. Nursing manager's leader behavior, expected by staff nurse are more complex and higher level which may combined with task pursuit leader type in concord pursuit leader of head nurse. Also according to Horsey and Blanchard theory(1977), the effectiveness of leadership becomes to be larger as the accordance rate between the behaviors of nurse leaders and followers reaction increase Two suggestions have been made based on the conclusion. 1. Studies on creating strategies in relation to development, management, selection of nurse leaders should be made based on this study. 2. There is a need for relative study of production and degree of similarity of leadership types based on this study.

• KIEAE Journal
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• v.1 no.1
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• pp.35-43
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• 2001

The VOC, which were detected from the newly built house, exist as a certain number of types according to the characteristics of the change of VOC concentration indoors. In this paper, we aim to divide the VOC into types so that those with similar characteristics of the transition of their concentration are in the same group and select the representative compound according to each classified type, and to verify these processes statistically in order to verify and propose new method creating the representing index of the VOC concentration in indoor which is used in evaluation of the degree of air pollution. As a result, the characteristic of the change of VOC concentration in the indoor can be divided into three types. Type1; the group in which the concentration is relatively high right after the completion of the house, and then decreases rapidly. Type2; the group in which the concentration is relatively low right after the completion of the house, and then although it shows the tendency of increasing and decreasing repeatedly, it decreases overall. Type3 is the group, which show only one peak at a certain time during the measuring period. As the method like this was verified to have the statistical significance, the Ethylbenzene was selected as the representative compound of type1, and Styrene was selected as that of type2. Moreover, if considering transition of the VOC from the point of similarity, the research method of making the classification and the selection of the representative compound in this study are said to be significant method.

• International Journal of Highway Engineering
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• v.19 no.5
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• pp.69-75
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• 2017

PURPOSES : The purpose of this study is to evaluate different types of Ground Penetrating Radar (GPR) testing for characterizing the road cavity detection. The impulse and step-frequency-type GPR tests were conducted on a full-scale testbed with an artificial void installation. After analyzing the response signals of GPR tests for detecting the road cavity, the characteristics of each GPR response was evaluated for a suitable selection of GPR tests. METHODS : Two different types of GPR tests were performed to estimate the limitation and accuracy for detecting the cavities underneath the asphalt pavement. The GPR signal responses were obtained from the testbed with different cavity sizes and depths. The detection limitation was identified by a signal penetration depth at a given cavity for impulse and step-frequency-type GPR testing. The unique signal characteristics was also observed at cavity sections. RESULTS : The impulse-type GPR detected the 500-mm length of cavity at a depth of 1.0 m, and the step-frequency-type GPR detected the cavity up to 1.5 m. This indicates that the detection capacity of the step-frequency type is better than the impulse type. The step-frequency GPR testing also can reflect the howling phenomena that can more accurately determine the cavity. CONCLUSIONS :It is found from this study that the step-frequency GPR testing is more suitable for the road cavity detection of asphalt pavement. The use of step-frequency GPR testing shows a distinct image at the cavity occurrences.

• Journal of Digital Convergence
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• v.12 no.5
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• pp.345-351
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• 2014

The purpose of this study was to identify the difference between job satisfaction and organizational commitment by the type of time management behavior in clinical nurses. Total 208 nurses were recruited from clinical settings where located in Seoul and Daejeon, South Korea. Data were collected using self-administered method with structured questionnaire between August 2012 and January 2013. Descriptive statistics, K-mean cluster analysis, one-way ANOVA were performed for data analysis. As results, the type of time management behavior were classified into four types such as unconcern type, accomplishment type, urgency type and selection & concentration type. Among four types, nurses who belonged to be accomplishment and selection & concentration type were tend to have positive behaviors in terms of time managements as they had high scores in job satisfaction. Therefore, further study on whether types of time management are related with organizational culture including commitment and effectiveness should be explored.

• Proceedings of the KWS Conference
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• 1993.05a
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• pp.68-69
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• 1993

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.5
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• pp.565-581
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• 2003

Statement of problem : A scientific examination and understanding of overall aspects of the natural dentition is the first step involved in making a satisfactory selection in the shade of an aesthetic prosthesis. Proper natural shade selection of the prosthetic restoration that is in harmony with the remaining dentition is as important aesthetically, as harmony of form and function in the anterior dentition. Clinically, the most commonly applied method of shade selection has been visual, but because of the subjective nature inherent to this method, shade selection results are variable and can be influenced by such factors as the technician, the type of shade guide used, and the type and intensity of the lighting. Purpose : The purpose of this study was to develop a more objective and scientific approach to examining and understanding the shade of teeth, which has in turn lead to the development of a number of shade analysis devices that present a more objective method of shade analysis. Material and Method : In this study, the shades of healthy anterior teeth were examined and analyzed using the recently developed digital shade analysis of the $ShadeScan^{TM}$ System. The study examined 80 individuals in their twenties, 40 males and 40 females, presenting 6 healthy, unrestored maxillary anterior teeth. Tooth brushing and oral prophylaxis were performed prior to evaluation. The ShadeScan handpiece was used to acquire images of the 6 maxillary anterior teeth. These images were analyzed using the Vita/Classical mode of the $ShadeScan^{TM}$ Software, and shade maps of each tooth were acquired and divided into cervical, middle, and incisal thirds. The shade distribution of each third, left and right symmetry, and gender differences were investigated and analyzed. Results : The results of the study are as follows : 1. An overwhelming majority of the examined teeth were found to possess shades belong to Group A, with the greatest variations occurring at the middle and cervical thirds of the maxillary central and lateral incisors, in both male and female subjects. 2. Canines of both male and female subjects showed left and right symmetry with uniform shade distribution of A4 and C4, while the lateral and central incisors showed left-right symmetry of the incisal 1/3 with a uniform shade distribution of A2 and A3 shades 3. No significant differences in shade distribution were seen between genders in maxillary canines, whereas maxillary central and lateral incisors showed differences at the middle and cervical thirds between male and female subjects The results of this study show that with the exception of maxillary canines, maxillary anterior teeth display a diverse shade distribution as well as gender differences. Conclusion : Clinically, when making a shade selection using the existing shade guide, one must consider the fact that even a single tooth consists of a variety of shades. The results of this study show that when selecting a shade from a number of groups is difficult, shades from A group are the most consistent with the natural shade or maxillary anterior teeth.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.11
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• pp.1091-1097
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• 2017

Sales of commercial-type cooling fans intended for application in military electronics are often discontinued during equipment production. This results in requirements for alternative fan selection as well as equipment performance and reliability tests, such as high-temperature operation testing. This study deals with alternative fan selection and verification methods that can be used during the production process. First, an alternative fan was selected by calculating the flow and pressure required to effectively cool the equipment, then the feasibility of the selected fan was verified using a reliable CFD heat dissipation analysis model. Following this, a high-temperature operation test was performed using the alternative fan in the equipment. Results demonstrated that the equipment satisfied its required function in a high-temperature environment, and the main parts as well as internal air temperature were found to be thermally stable.