• Smart Structures and Systems
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• v.16 no.4
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• pp.579-591
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• 2015

This paper investigates a magnetoelectric (ME) vibration energy harvester that can scavenge energy in arbitrary directions in a plane as well as wide working bandwidth. In this harvester, a circular cross-section cantilever rod is adopted to extract the external vibration energy due to the capability of it's free end oscillating in arbitrary in-plane directions. And permanent magnets are fixed to the free end of the cantilever rod, causing it to experience a non-linear force as it moves with respect to stationary ME transducers and magnets. The magnetically coupled cantilever rod exhibits a nonlinear and two-mode motion, and responds to vibration over a much broader frequency range than a standard cantilever. The effects of the magnetic field distribution and the magnetic force on the harvester's voltage response are investigated with the aim to obtain the optimal vibration energy harvesting performances. A prototype harvester was fabricated and experimentally tested, and the experimental results verified that the harvester can extract energy from arbitrary in-plane directions, and had maximum bandwidth of 5.5 Hz, and output power of 0.13 mW at an acceleration of 0.6 g (with $g=9.8ms^{-2}$).

• Korean Journal of Remote Sensing
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• v.36 no.5_4
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• pp.1167-1177
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• 2020

In this study, we established the process for collecting and utilizing video scripts of disaster site based on public-private partnerships. It is for the purpose of actively utilizing private capabilities in disaster management, and quickly sharing video scripts to identify field conditions. Based on the experience of actual operation of public-private partnerships system in the event of typhoon in 2019, we also derived implications for continuous operation of the process. Results are meaningful in that the government established the process for collecting and utilizing video scripts through public-private partnerships during the initial disaster response phase. And we also confirmed the possibility of spreading positive perception of disaster management organizations. However, there is a limit to the actualization and practical use of performance as an experimental pilot operation in the R&D stage. In addition, for continuous operation of the system, it is necessary to prepare institutional support measures such as organization, infrastructure for operating, programs of education and training, and policy making.

• Journal of Korean Society for Quality Management
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• v.41 no.4
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• pp.683-692
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• 2013

Purpose: Car seats affect customer satisfaction greatly when the seats' design is changed because car holders are in close contact with the seats. However, the improvement of the current seats' design involves risks such as investment cost, and therefore it needs strategic operating measures from the perspective of customers. Until now, operations of seats' specification have been decided by technical-push rather than market-pull, and carried out based on professionals' experience without measuring customer satisfaction correctly. The purpose of this study is to present a systematic approach to measure customers' perception on the car seats using the Kano model and pairwise comparison technique. Methods: The authors derive 17 major functions of a car seat by analyzing major components of car seats, and conduct a survey of 141 adults who hold a car(s). Results: The results show that consumers perceive the adjustable functions of front seats as must-be while the same functions for rear seats are perceived as attractive. In particular, motor operated functions for both front and rear seats increase customer satisfaction greatly if they are presented. Conclusion: This study shows that how much customer (dis)satisfaction will increase if a function of car seats (non)fulfilled, and therefore, the results of this study will provide practitioners and R&D personnel in new automobile seats development projects with useful information.

• Korean Institute of Interior Design Journal
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• v.26 no.4
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• pp.30-41
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• 2017

Sunlight is perceived by human beings first through the epidermis to space, and is a non - material medium that provides physical awareness of space, diversified expression of spaces, and plenty experience. The purpose of this study is to investigate the characteristics of active building skin based on the inflow of natural light required by humans, looked through among the works of Jacques Herzog & Pierre de Meuron, which show the characteristics of active building skin, TEA(Tenerife Espacio de las Artes, 2008), Messe Basel New Hall (2013) and Elbphilharmonie (2016). First, the interaction between Sunlight and space is divided into spatial characteristics and sensitivities according to their concepts, properties, and characteristics. The characteristics of active skin by light are classified into a physical approach and a constructive approach. Second, (El Croquis 152/153) and analyzed the images, detail drawings, and elevations, and simulated them in 3D to express the relationship between light and active building skin. Third, the changes of light intensity, light color, and distribution of light according to the time of light entering and the skin are determined from 6:00 am to 6:00 pm. Fourth, the images taken from January 30th to February 7th, 2017 on the site were compared with the computer simulated images, and the relationship between active skin and light was compared. This study is to recognize the existence and necessity of light required for human being through the activated epidermis differentiated from the limited or closed epidermis focused on information transmission, I would like to emphasize that I would like to take a step closer to the necessity and possibility of new attempts and developments so that I can feel the various experiential spaces by.

• Journal of Korean Society of Rural Planning
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• v.21 no.4
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• pp.157-165
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• 2015

The purpose of this study is on identifying charactreistics and management direction of complementary pond of Dalmaji village in Gangjin. Accordingly, this village was indicated as Experience and Resort village by Korean government. This study describes the construction background and characteristics and identifies species diversity and characteristics through field survey. For this, literature and field survey was performed. In field survey, vegetational survey was performed in Aug. of 2015. D(Dominant degree) and S(Sociability degree) was measured by Brown-Blanquet's method. The answer was searched from Myungsanron(明山論), a textbook of Fengsui(風水) in Joseon dynasty. Of these causes, it was considered that the representative one is a protection of fire and infectious disease because the Wolgak mountain is a fire mountain(火山) as a stone mountain in Fengsui. The results demonstrate decline of aquatic ecosystem because of neglect management. The total number of species was 24. Of the species, Zelkova serrata is a natural vegetation of this complementary forest. This is nominated as Lagerstroemia indica and Camellia japonica community. Species composition demonstrate the characteristics of Korean southern region as mixed forest of evergreen trees and deciduous ones which are indigenous plants. It was considered Juniperus chinensis KaizukaVariega in central round island was planted in Japanese colonial period and it have to be removed. It was considered that name of moon pond and moon island etc. projects the mind of village ancestors which are going to reach an ideal condition of moon. And management of quantity and depth of pond water was critical for restoration of disappearing lotus from related literature. Periodic management was needed for ecological structure and function improvement because of ecological disturbance by the invasive plants like Humulus japonicus.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.1
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• pp.96-102
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• 1994

Factors affecting non-proficient analytical ability were compared and evaluated by rating of laboratories and round. Analyst Indices between proficient and non-proficient participants were different. Coefficients of determination($R^2$) for standard of toluene, xylene and trichloroethylene of the 4th round between some proficient and non-proficient participants were significantly different(p<0.05). But, there was no difference in the 5th round. Average desorption efficiency of non-proficient participants was 88%-98%, which was lower than 96%-100% of some randomly selected proficient participants. Also non-proficient participants have a large variance of desorption efficiency, 11.79-19.69%. In the 5th round, desorption efficiency of metyl iso-butyl ketone(MIBK) reported by all participants was lower than 90% tested by NIOSH and especially low compared to other analytes. Participants evaluated to be non-proficient in the metal part have 85%-100.84% of average recovery, which was larger variance than 98% of some proficient participants. Although it is difficult to find quantitatively factors causing non-proficiency in analytical ability, pretreatement techniques and experience of analyst seems to be more important factors to produce accurate analytical result.

• Journal of Korean Library and Information Science Society
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• v.32 no.1
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• pp.53-71
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• 2001

The purpse of this study is to analy7~ the public library program development for the 01d Age and voluntary activities for community development. The study area that are Anyng city, Uiwang city and Goonpo city who was the Old Age from 60 years old to 8lyears. In United State Old Age mnning in 1955 of voluntary Activities. But Korea Old Ages had not be experience of voluntary service activities not so much. So, through the public Library Program for the Old Age increase participation community development that voluntary of care the Youth and Guide stranger in city. Also, A study on The Public Library program development for the Old Age in Community Development that change police of public library through thls study. This study is based on the (1) Searching the cornmunit\ulcorner. development police in the Old Age in community (2) Study method in library educate for The Old Age (3) the Old Age Participation of community development Activities in local Government (4) Exploring the improvemts based on the study. And also training of the old Age for human resource development.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.4
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• pp.1644-1651
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• 2013

The purpose of this study was to investigate the influence of distance education experience using users' avatars in virtual reality space on their teaching efficacy belief. There were 9 participants who were enrolled in a course in doctoral program of education department in J University for the study. The first class of six sessions was face to face class on how to use Second Life and the 14 classes of 3 sessions were done in a classroom of Second Life. According to the analysis of reflection notes, interviews, researcher's observations of 5 participants, their experiences of presentation and taking classes in distance education using their own avatars in Second Life had positive influence on participants' teaching efficacy belief in their future working for distance education using avatars of Second Life. The implication of this study is to show some conditions for successful distance education as well as to see the potential of distance education in 3D virtual reality space using avatars. This study will contribute to promote the future study in distance education field.

• Journal of the Korea Convergence Society
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• v.6 no.5
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• pp.39-47
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• 2015

This study was to explore the relationship between the job stress and mental health of nurses. The participants were 291 nurses from two general hospitals in C city. Job stress, mental health, and general characteristics of nurses were measured. The data were collected from April 7 to 30, 2015. The collected data was analyzed with descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients and multiple regression analysis. The mean score for job stress was 61.96 point and 92.45 for mental health. The mean scores for job stress were significantly different by age and turnover experience in nurses. Job stress was positively correlated with mental health(r=.233, p=.000). The findings indicate that job stress has an influence on mental health. We'd like to provide basic data on developing convergence programs to prevent and intervene job stress considering nurses' mental health problems in nursing service that is rapidly changing and specialized for the convergence generation.

• Journal of Korea Society of Digital Industry and Information Management
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• v.15 no.4
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• pp.197-212
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• 2019

The purpose of this study is to identify the maturity stages of venture firms through classification analysis, which is widely used as a big data technique. Venture companies should develop a competitive advantage in the market. And the maturity stage of a company can be classified into five stages. I will analyze a difference in the growth stage of venture firms between the survey response and the statistical classification methods. The firm growth level distinguished five stages and was divided into the period of start-up and declines. A classification method of big data uses popularly k-mean cluster analysis, hierarchical cluster analysis, artificial neural network, and decision tree analysis. I used variables that asset increase, capital increase, sales increase, operating profit increase, R&D investment increase, operation period and retirement number. The research results, each big data analysis technique showed a large difference of samples sized in the group. In particular, the decision tree and neural networks' methods were classified as three groups rather than five groups. The groups size of all classification analysis was all different by the big data analysis methods. Furthermore, according to the variables' selection and the sample size may be dissimilar results. Also, each classed group showed a number of competitive differences. The research implication is that an analysts need to interpret statistics through management theory in order to interpret classification of big data results correctly. In addition, the choice of classification analysis should be determined by considering not only management theory but also practical experience. Finally, the growth of venture firms needs to be examined by time-series analysis and closely monitored by individual firms. And, future research will need to include significant variables of the company's maturity stages.