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A Research on the Development of Service Nature Measurement Items in the Sevice Economic Era (서비스 경제로의 전환에 따른 서비스본질 측정항목 개발 연구)

  • An Sehong;Kim Hyunsoo
    • Journal of Service Research and Studies
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    • v.11 no.1
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    • pp.59-79
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    • 2021
  • Service-related research in accordance with the transition to the service economy era has been conducted in a wide variety of ways, but the development of a service-related scale suitable for the present time is still insignificant. The purpose of this study is to define the nature of services and to develop measurement items for them. First, four categories of service nature were adopted in the previous study. The four categories are 'relationship', 'interactivity', 'horizontality', and 'harmony'. In this study, sub-factors and specific items of each of these four service essences were extracted and developed as measurable items. As a qualitative study, the four categories of sub-factors were extracted, and a mixed study was adopted to prove the reliability and validity of the extracted factors through quantitative studies. The scale items were identified through literature study, free response method, and Delphi technique, and the measurement items were refined through a second questionnaire of 30 Delphi panels composed of experts. As a result of the study, 15 out of 52 questions for relationship, 11 out of 45 questions for bilateral direction, 9 out of 33 questions for horizontality, and 17 out of 61 questions for harmonization were derived after secondary refining. Through this study, it was possible to uncover new essential items suitable for the service economy era. SNS, network, synergy, platform, system, real name, and breakthrough are concepts that have not been obtained in previous studies, and can be seen as contributions of this study. However, due to various limitations, this study did not cover all aspects of the service, but mainly dealt with people-centered services, which are part of the service. In the future, it is necessary to study the development of service essence measurement items for the overall aspect of services developed according to the evolution of the service economy era.

A Study on Compact Section Requirements for Plate Girder Web Panels with Longitudinal Stiffeners (수평보강재가 설치된 플레이트거더 복부판의 조밀기준에 관한 연구)

  • Lee, Myung Soo;Lee, Doo Sung;Lee, Sung Chul
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.6A
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    • pp.503-512
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    • 2010
  • In AASHTO LRFD (2007), a compact section is defined as a section in which no premature failure caused by local buckling of web and flange plate or later buckling occurs before the section reaches the plastic moment, Mp. The current AASHTO LRFD (2007) provides the compact section requirement by limiting the web slenderness only for webs without longitudinal stiffeners. The role of longitudinal stiffener is to increase the web buckling strength caused flexure. Although a web does not satisfy the compactness requirement without longitudinal stiffeners, the web buckling can be prevented by use of valid longitudinal stiffeners. Therefore, the web may be able to reach the plastic moment. However, the reason why a longitudinal stiffener may not be used to satisfy compactness requirement is not cleary explained in AASHTO LRFD (2007). In this study, the buckling and ultimate strength behaviors of stiffened webs subjected to bending are investigated through the linear buckling and nonlinear finite element analysis. It is found that steel plate girders having webs that do not satisfy the compactness requirement are able to reach the plastic moment if the longitudinal stiffeners have sufficient rigidities and are properly located. From a nonlinear regression analysis of the results, a new compactness requirement is suggested for webs stiffened with one longitudinal stiffener.

Evaluation of Fire Performance of RC Slabs with Half-Depth Precast Panels (반단면 프리캐스트 패널을 적용한 RC 슬래브의 내화성능 평가)

  • Chung, Chul-Hun;Im, Cho-Rong;Kim, Hyun-Jun;Joo, Sang-Hoon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.4A
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    • pp.391-398
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    • 2010
  • The fire performance of RC slabs with half-depth precast panel after exposure to the ISO-834 fire standard without loading has been experimentally investigated. During heating, according to the ISO 834 fire curve, concrete spalling was observed for concrete without PP(polypropylene) fibers. No spalling occurred when heating concrete containing PP fibers. The maximum temperature of RC slabs with PP fibers with half-depth precast panel was lower than that of concrete without PP fibers. The ultimate load after cooling of the RC slabs that were not loaded during the furnace tests was evaluated by means of 3 points bending tests. The ultimate load of the RC slabs without PP fibers showed a considerable reduction (around 32.5%) of the ultimate load after cooling if compared with of RC slabs with PP fibers. The ultimate load of the RC slabs with half-depth precast panel with PP fibers is higher than that of a full-depth RC slabs with PP fibers. Also, the addition of PP fibers and the use of half-depth precast panel improve fire resistance.

Development of Health Status Scale for Abdominal Obesity Elderly (복부비만 노인의 건강수준 측정도구 개발)

  • Kim, Jeong Soo
    • 한국노년학
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    • v.30 no.4
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    • pp.1095-1106
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    • 2010
  • The purpose of this study was to develop a Abdominal Obesity Elderly(AOE) Health Status Scale to assess self rated health level. The subjects of this study were total 255(pretest 56, test 199) elderly over 65year. The data were collected between June to August, 2009. The method of this study as follow: items generation, test of validity and reliability, 5 panels of experts reviewed the preliminary questionnaire and then data were collected from elderly. Factor analysis, Cronbach's alpha, mean, standard deviation were analyzed the data by SPSS-Win 12.0 program. Results of factor analysis, 5 factors with a total of 16 items extracted that were Social level(Social participation 6 items, Physical Activity 2 items), Physical level(Disease Perception 4 items, Physical Index 2 items), Psychological level(Emotional Support 2 items). The reliability of the AOE health status scale was .868(Conbach's α). In the factor analysis Conbach's α correlations for the 5 factors ranged from .806 to .577. Therefore, Content validity, construct validity, reliability of the AOE health status scale were established. The AOE health status scale is a reliable and valid instrument which abdominal obesity elderly health status can be assessed.

What is an Appropriate Promotion Strategy for Korean Wheat Consumption? - Find Out in the Sensory Evaluation of Rice Meal Versus Rice Containing Wheat Meal by Age Groups-

  • Kyunsik Lee;Sehwa Lim;Kyeonghoon Kim;Jinhee Park
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.321-321
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    • 2022
  • Wheat was brought to solve food scarcity with aid from the United States caused by the Korean War. The Korean government launched a campaign to encourage mixed rice and wheat meals due to shortage of rice production in the 1960s, Wheat consumption began in earnest. However, it is difficult to rebuild the domestic wheat production base devastated by the Korean War with the technology at the time. Thus, wheat was mainly consumed from imported in the past. Since then, as wheat consumption has increased due to westernization and diversification of dietary life, wheat became the second staple grain in Korea. In this situation, the government enacted the Wheat Industry Promotion Act to create a basis for sustainable production and consumption of wheat in Korea. This study sought to improve the self-sufficiency of domestic wheat by examining the possibility of using "Ariheuk", a variety of new Korean wheat, as a rice supplement in the same context as the govemment's policy. Wheat has been used as a raw material for the processed food, such as noodles and bread. However, we approached it by using whole wheat as a nutritional grain. Participants were recruited from the agri-food consumer panel conducted by Rural Development Administration. We set a final sample of 525 consumer panels based on the age of census household heads. The experiment was conducted in such a way that participants cooked and ate 100% rice meal and rice containing 20% whole wheat meal. Participants completed the sensory evaluation questionnaire with online. For this experiment, all participants were given same whole wheat product. The sensory evaluation questionnaire consisted of color, glossiness, stickiness, aroma, chewing, sweetness, nuttiness, chewiness, softness, bursting, flavor, texture and swallowability. The sensory evaluation results were analyzed by giving -3 points to +3 points. The former points were given to the response that 100% rice meal is very superior to the response that rice containing 20% whole wheat meal. The latter points were given vice versa. Zero point was given to the response that they are similar each other. As a result, rice with 20% whole wheat meal was better than 100% rice meal in terms of color, aroma, chewiness, bursting and flavor. In case of sweetness and glossiness, there didn't exist significantly different. On the other hands, 100% rice meal was better in terms of softness and swallowability. As a result of ANOVA by age groups, from 30s or younger to 60s or more, there was significant difference among the groups in terms of color, chewiness and bursting. As a result of post-hoc analysis with Duncan's multiple range test (p < 0.05), 50s were evaluated to be significantly superior in color, chewiness and bursting compared to other age groups. In conclusion, it is appropriate to use whole wheat as a supplement to rice in order to improve the self-sufficiency of domestic wheat. As a strategy to promote domestic wheat consumption, in case of Ariheuk, it is necessary to provide an experience through whole wheat tasting and to establish a marketing strategy segmented by age groups.

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An Experimental Study on the Development of a Cabin Noise Reduction System for Improving Ship Habitability (선박 거주성 향상을 위한 선실 소음 저감 시스템 개발에 관한 실험적 연구)

  • Young-Choul Seo;Deug-Bong Kim;Chol-Seong Kim
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.6
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    • pp.620-627
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    • 2023
  • Ship noise is one of the important factors for the living and health of seafarers, and ef orts to reduce ship noise are actively underway. There are two methods of noise reduction: passive noise Control (PNC) and active noise control (ANC). Unlike cars and airplanes, ANC is not widely used for noise reduction on ships. This study aimed to reduce the noise generated in the engine room by using soundproof panels and high-frequency vibration generators, as well as active noise control (ANC). For this purpose, an experimental model was made using an acrylic box, and the noise reduction effect was measured under four conditions. The experimental results are as follows: First, the soundproof panel had a noise reduction effect in all ranges from 55 dB to 85 dB. In the case of using a high-frequency vibration generator, there was no ef ect in the low noise range such as 55 dB(A), but there was a noise reduction effect in the high noise range such as 70.8 dB(A) and 85 dB(A).Second, when the soundproof panel and the high-frequency vibration generator were used simultaneously, the noise reduction ef ect was up to -2.2 dB(A). The results of this experiment were obtained from an experimental model made of acrylic, and they may be different from actual ships made of steel plate. In future studies, we plan to experiment using iron plate (considering the material, thickness, and structure) used in actual ships. We hope that this study will help to improve the living environment and health of seafarers on ships.

On-orbit Thermal Characteristic for Multilayered High Damping Yoke Structure Based on Superelastic Shape Memory Alloy for Passive Vibration Control of Solar Panels (태양전지판의 수동형 제진을 위한 초탄성 형상기억합금 기반 적층형 고댐핑 요크 구조의 궤도상 열적 특성 분석)

  • Min-Young Son;Jae-Hyeon Park;Bong-Geon Chae;Sung-Woo Park;Hyun-Ung Oh
    • Journal of Aerospace System Engineering
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    • v.18 no.1
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    • pp.1-10
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    • 2024
  • In a previous study, a structure of a superplastic yoke consisting of a thin FR4 layer laminated with viscoelastic tape on both sides of a shape memory alloy (SMA) was proposed to reduce residual vibration generated by a deployable solar panel during high motion of a satellite. Damping properties of viscoelastic tapes will change with temperature, which can directly affect vibration reduction performance of the yoke. To check damping performance of the yoke at different temperatures, free damping tests were performed under various temperature conditions to identify the temperature range where the damping performance was maximized. Based on above temperature test results, this paper predicts temperature of the yoke through orbital thermal analysis so that the yoke can have effective damping performance even if it is exposed to an orbital thermal environment. In addition, the thermal design method was described so that the yoke could have optimal vibration reduction performance.

An Assessment on the Sound Quality of the Car Audio System Using the Orthogonal Designs (직교배열법을 이용한 차량 음향 시스템의 음질평가)

  • Doo, Se-Jin;Choi, Kyung-Mee
    • The Journal of the Acoustical Society of Korea
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    • v.27 no.5
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    • pp.229-238
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    • 2008
  • Audio tuning improves not only the sound quality of the car audio but also the quality of the completed car itself. However without the subjective assessment on the users' preferences, it is hard to tune the car audio satisfying them. Even though there are lots of factors to be considered to assess the preferences, only a restricted number of factors should be included in the experiment because the total number of experiments increases rapidly as the number of factors in the experiment increases. A large number of factors make it hard to explore the relationship between the sound quality and the sound characteristics and also makes the panels exhausted. In this paper, 8 sound characteristics, each with 2 levels, are considered for the experiment. An orthogonal design of experiment is suggested to reduce the number of experiments from 256 to 16. The analysis of variance is applied to show that Treble is the most significant characteristic of the reproduced sound of the given pop music. Also Deep Bass, SAD, and the interaction between Treble and SAD are found to be significant. For the given classic music, SAD is the only characteristic which turns out to be significant.

Flexible Planar Heater Comprising Ag Thin Film on Polyurethane Substrate (폴리우레탄 유연 기판을 이용한 Ag 박막형 유연 면상발열체 연구)

  • Seongyeol Lee;Dooho Choi
    • Journal of the Microelectronics and Packaging Society
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    • v.31 no.1
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    • pp.29-34
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    • 2024
  • The heating element utilizing the Joule heating generated when current flows through a conductor is widely researched and developed for various industrial applications such as moisture removal in automotive windshield, high-speed train windows, and solar panels. Recently, research utilizing heating elements with various nanostructures has been actively conducted to develop flexible heating elements capable of maintaining stable heating even under mechanical deformation conditions. In this study, flexible polyurethane possessing excellent flexibility was selected as the substrate, and silver (Ag) thin films with low electrical resistivity (1.6 μΩ-cm) were fabricated as the heating layer using magnetron sputtering. The 2D heating structure of the Ag thin films demonstrated excellent heating reproducibility, reaching 95% of the target temperature within 20 seconds. Furthermore, excellent heating characteristics were maintained even under mechanically deforming environments, exhibiting outstanding flexibility with less than a 3% increase in electrical resistance observed in repetitive bending tests (10,000 cycles, based on a curvature radius of 5 mm). This demonstrates that polyurethane/Ag planar heating structure bears promising potential as a flexible/wearable heating element for curved-shaped appliances and objects subjected to diverse stresses such as human body parts.

Analysis of Environmental Odor Factors for Dorim Stream in Gwanak-gu, Seoul (서울시 관악구 도림천 복개 정도에 따른 환경 악취 요인 분석)

  • Soyoung Park;Gokce Nur Ayaz;Heewon Kim;Hyungkee Yoon;Taehong Kwon;Sungkyoon Kim
    • Journal of Environmental Health Sciences
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    • v.50 no.2
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    • pp.83-92
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    • 2024
  • Background: In this study, we investigate the rapid increase in environmental odors and notable rise in civil complaints near Dorim Stream in the Gwanak-gu area of Seoul. Objectives: This study aims to identify the causal compounds responsible for environmental odors in the Dorim Stream and investigate the structural characteristics of the stream that influence odor generation. Methods: The research methodology involved setting up 41 sampling points, selecting panels for direct sensory evaluation to assess odor intensity, measuring dissolved oxygen and hydrogen sulfide concentrations, and using all-in-one low-temperature desorption gas chromatography (ATD-GC) and thermal desorption-gas chromatography-mass spectrometry (TD-GC/MS) analysis to identify odor-causing compounds. Results: The evaluation of Dorim Stream revealed that in areas with complete meandering, there were lower dissolved oxygen levels (4.5±2.67 mg/L) and higher odor intensity (4.0±0.92), while in partially meandering sections, higher dissolved oxygen levels (7.8±1.15 mg/L) and lower odor intensity (2.8±1.06) were observed. Hydrogen sulfide levels measured with sensors increased with higher temperatures, especially in the afternoon hours (12:00~14:00). Acetaldehyde was the dominant odor compound detected in both the Bonglim Bridge (0.4 ppm) area and Guro Bridge area (0.867 ppm), with concentrations more than twice as high near Guro Bridge. Odor-causing compounds identified by TD-GC/MS indicated a pungent, sulfurous odor in the Guro Bridge area and a musty odor in the Bonglim Bridge area. Conclusions: This study categorizes and analyzes the sources of odor in Dorim Stream in Seoul based on meandering patterns and the distribution of sewage facilities, highlighting the potential odor issues associated with combined sewage systems and sewer junctions and suggesting policy improvements.