• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.3
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• pp.488-493
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• 2008

This paper represents a dual-mode type transmission technique for a high reliable narrow-band power line communication(PLC) modem, and its design and implementation of a system-on-chip(SoC). The proposed transmission technique is based on a Chirp modulation for the purpose of overcoming time variations of power line channel environments in the narrow-bandwidth of the frequency range of 95-145.5 kHz. The designed modem is fabricated utilizing a mixed 0.18 ${\mu}m$ CMOS technology. Especially, according to the power line channel environments the data transmission rate can be selectively changed into 2.5 kbps and 480 bps. The total hardware complexity of the implemented chip is about 50,000 gates, the power consumption is about 26mW, and the operating frequency is up to 5.12 MHz.

• Journal of Fashion Business
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• v.25 no.4
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• pp.79-91
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• 2021

Currently, chatbot, a conversational platform based on artificial intelligence, is drawing attention as a new marketing channel. This study attempted to verify the effect of the anthropomorphism, message type, and media self-efficacy level on purchase intention. The experimental design of this study was a 2 (anthropomorphism level of shopping chatbot: low vs. high) × 2 (message type: factual vs. evaluative) × 2 (media self-efficacy: low vs. high) three-way mixed analysis of variance (ANOVA). This study conducted a survey by the convenience sampling method of 402 women in their 20s and 30s living in Seoul and the Gyeonggi area who were aware of chatbot services. For the final analysis, 388 questionnaires were used. Data were analyzed with the SPSS 23 program and three-way ANOVA. Simple main effects analysis was conducted. The results of this study were as follows. First, there were statistically significant differences in purchase intention according to anthropomorphism level, message type, and media self-efficacy. Second, message type and media self-efficacy showed statistically significant interaction effects on purchase intention. Lastly, anthropomorphism and the media self-efficacy level and the message type of the shopping chatbots showed significant three-way interaction effects on purchase intention.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.359-362
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• 2004

In multi-dimensional image, ICA-based feature extraction algorithm, which is proposed in this paper, is for the purpose of detecting target feature about pixel assumed as a linear mixed spectrum sphere, which is consisted of each different type of material object (target feature and background feature) in spectrum sphere of reflectance of each pixel. Landsat ETM+ satellite image is consisted of multi-dimensional data structure and, there is target feature, which is purposed to extract and various background image is mixed. In this paper, in order to eliminate background features (tidal flat, seawater and etc) around target feature (laver farm) effectively, pixel spectrum sphere of target feature is projected onto the orthogonal spectrum sphere of background feature. The rest amount of spectrum sphere of target feature in the pixel can be presumed to remove spectrum sphere of background feature. In order to make sure the excellence of feature extraction method based on ICA, which is proposed in this paper, laver farm feature extraction from Landsat ETM+ satellite image is applied. Also, In the side of feature extraction accuracy and the noise level, which is still remaining not to remove after feature extraction, we have conducted a comparing test with traditionally most popular method, maximum-likelihood. As a consequence, the proposed method from this paper can effectively eliminate background features around mixed spectrum sphere to extract target feature. So, we found that it had excellent detection efficiency.

• Asia pacific journal of information systems
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• v.15 no.4
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• pp.165-192
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• 2005

This study introduces how to estimate the monetary value of intellectual capital of a public research institute by incorporating a non-market valuation technique, the choice experiments(CE). CE is a survey-based environmental valuation technique that has increasingly been popular over the last decade. The members of institute E, a typical type of public research institutes in Korea, were surveyed, before the data were fit to the conditional logit and mixed logit models. The total value of the institute's intellectual capital was estimated at approximately W3,377 billion for the year 2003. The institute's human, structural and relational capitals that comprise the intellectual capital were estimated at W18.7 billion, W10.7 billion and W4.4 billion respectively, for each of the components' index values improving by 1%. The human capital was placed a higher value than the other two. The study also shows that CE is a flexible technique that enables the researcher to estimate the monetary value of the intellectual capital whatever the index values of the component capitals and to interpret model estimation results more in depth by incorporating the mixed logit, a state-of-the-art discrete choice model, than the conventional conditional logic.

• Korean Management Science Review
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• v.12 no.1
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• pp.139-156
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• 1995

This study addresses basic requirements for mathematical programming software, discusses considerations in designing these software, implementation issues facing in these types of applications development, and shows some examples of codes being developed in the course. This type of projects requires long and ever-changing evolutionary phases. The experience is therefore, valuaable in suggesting some useful hints which may be salvaged for similar projects as well as providing reusable codes. In particular, scanning and parsing the free-format inputs, symbol table management, mixed-language programming, and data structures dealing with large sparse matrices are indispensable to many management science software development. Extensions to be made are also discussed.

• International Journal of Human Ecology
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• v.7 no.2
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• pp.17-27
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• 2006

The purpose of this research was to find out the preferences in HMUBs for living space in respondents' later life. For this purpose, this research was conducted by social survey research using a questionnaire for those who lived in an urban area around Seoul. The data was collected from November to December, 2005. The results of this research were as follows. Firstly, respondents agreed with living in high rise mixed use buildings in their later life because of convenience. Willingness to move into HMUBs was positive. Concerning preferred physical features, residents preferred living in either lower floors or higher floors because of safety or fine views. Regarding the usage of common space and facilities, they wanted to use them with other generations and preferred 2 bedroom type unit located in a suburban area. Secondly, the preference for living in a HMUB in later life was higher in women respondents than in men. Thirdly, the preference for living in a HMUB in later life was higher in upper floors than lower floors according to property and asset value. As a conclusion, the development of HMUB housing for older people has a bright prospect for urban residents in Korea.

• KIEAE Journal
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• v.10 no.1
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• pp.109-116
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• 2010

The city means not only a geographical area as a role of the spatial boundary, but also a socio-economic place to communicate with each area. It requires various functions to get the income and economic-activities. But city has a limitation of a available land to provide the required functions and a sufficient space to supply the urban activity. Therefore, the development trend of city has not been to spread to the horizontal area any more and considered the vertical area. In addition, various functions put into a massive building because many people want to solve the daily requirements without spending time and cost in outer area. In this paper, it aimed at classifying the mixed-use building into function, circulation, relation according to the public and private space and the building shape to provide the design information such as land area, functional complex, accessibility, etc.. The classification of the mixed-use buildings is divided into four areas. The data are collected with foreign countries in Japan, Europe and US. Results of the study are as follows; First, the commercial function is mainly centered with other functions. Second, after studied the development scale, accessibility, building form, the commercial and residential area overwhelmly share at the total area.

• The Journal of Advanced Prosthodontics
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• v.1 no.1
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• pp.31-36
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• 2009

PURPOSE. To determine the change in stability of single-stage, three different design of implant systems in humans utilizing resonance frequency analysis for early healing period(24 weeks), without loading. MATERIAL AND METHODS. Twenty-five patients were included into this study. A total of 45 implants, three different design of implant systems(group A,C,R) were placed in the posterior maxilla or mandible. The specific transducer for each implant system was used. ISQ(implant stability quotient) reading were obtained for each implant at the time of surgery, 3, 6, 8, 10, 12, 24 weeks postoperatively. Data were analyzed for different implant type, bone type, healing time, anatomical locations. RESULTS. For each implant system, a two-factor mixed-model ANOVA demonstrated that a significant effect on ISQ values(group A=0.0022, C=0.017, R=0.0018). For each implant system, in a two-factor mixed model ANOVA, and two-sample t-test, the main effect of jaw position(P > .005) on ISQ values were not significant. CONCLUSIONS. All the implant groups A, C and R, the change patterns of ISQ over time differed by bone type. Implant stability increased greatly between week 0 and week six and showed slow increase between week six and six months(plateau effect).

• Atmosphere
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• v.19 no.2
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• pp.169-182
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• 2009

To improve the performance of climate and numerical models, concerns on the land-atmosphere schemes are steadily increased in recent years. For the realistic calculation of land-atmosphere interaction, a land surface information of high quality is strongly required. In this study, a new land cover map over the Korean peninsula was developed using MODIS (MODerate resolution Imaging Spectroradiometer) data. The seven phenological data set (maximum, minimum, amplitude, average, growing period, growing and shedding rate) derived from 15-day normalized difference vegetation index (NDVI) were used as a basic input data. The ISOData (Iterative Self-Organizing Data Analysis), a kind of unsupervised non-hierarchical clustering method, was applied to the seven phenological data set. After the clustering, assignment of land cover type to the each cluster was performed according to the phenological characteristics of each land cover defined by USGS (US. Geological Survey). Most of the Korean peninsula are occupied by deciduous broadleaf forest (46.5%), mixed forest (15.6%), and dryland crop (13%). Whereas, the dominant land cover types are very diverse in South-Korea: evergreen needleleaf forest (29.9%), mixed forest (26.6%), deciduous broadleaf forest (16.2%), irrigated crop (12.6%), and dryland crop (10.7%). The 38 in-situ observation data-base over South-Korea, Environment Geographic Information System and Google-earth are used in the validation of the new land cover map. In general, the new land cover map over the Korean peninsula seems to be better classified compared to the USGS land cover map, especially for the Savanna in the USGS land cover map.

• Health Policy and Management
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• v.29 no.2
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• pp.184-194
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• 2019

Background: The extent of coverage rate of the public health insurance is still insufficient to meet healthcare needs. Private health insurance (PHI) plays a role to supplement coverage level of national health insurance in Korea. It is expected that reduce unmet need healthcare. This study was aimed to identify relationship between PHI type and the unmet healthcare need and its associated factors. Methods: Data were obtained from the 2014 Korea Health Panel Survey using nationally representative sample was analyzed. Respondents were 8,667 who were adults over 20 years covered by PHI but have not changed their contract. According to the enrollment form, PHI was classified into three types: fixed-benefit, indemnity, and mixed-type. To identify factors associated with unmet needs, multiple logistic regression conducted using the Andersen model factors, which are predisposing factors, enabling factors, and need factors. Results: Our analysis found that subjects who had PHI with mixed-type were less likely to experience unmet health care needs compared than those who did not have it (odds ratio, 0.80; 95% confidence interval, 0.66-0.98). As a result of analyzing what affected their unmet healthcare needs, the significant factors associated with unmet medical need were gender, marital status, residence in a metropolitan area, low household income, economic activity participation, self-employed insured, physically disabled, low subjective health status, and health-risk factors such as current smoking and drinking. Conclusion: The results of this study suggest that having PHI may reduce experience of unmet healthcare needs. Findings unmet healthcare needs factors according to various subjects may be useful in consideration of setting policies for improving accessibility to healthcare in Korea.