• The Journal of the Acoustical Society of Korea
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• v.31 no.7
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• pp.419-426
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• 2012

The pitch searching is a vital process in a vocoder. Generally, the method of pitch searching is employed after highlighting the periodicity, where a correlation is identified with the signal by changing the interval of two pulses. When the correlation value reaches the peak, the pitch can be found by the pulse interval because it is the repetition interval with most striking period. However if the identified period happens to be one of half period, double period or triple period, this cannot be considered as the pitch period. Many methods were suggested to solve this problem. An inaccurate pitch could be obtained as well, when there is an interval where signal amplitude is not constant but varies abruptly in the frame. To solve this matter, searching the pitch by dividing a frame into various subframes is adopted, but too much calculation has to be followed while it leads the correct value. This paper suggests an algorithm to resolve these two problems. First, to search the pitch after advance correction of the signal energy level with an estimated overall energy change ratio in the frame before pitch search to reduce half period, double period and triple period is suggested. Second, to vary the number of subframes by predicting the amplitude change rate in the frame by the energy ratio obtained by the above-mentioned method is advised. If these two methods are applied, the pitch searching time can be reduced and the general pitch searching performance can be improved without affecting the sound quality in the synthesized signal.

• Journal of dental hygiene science
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• v.6 no.3
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• pp.153-158
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• 2006

Bleaching of vital and nonvital teeth is becoming a more commonly used treatment in the dental office and at home. To improve appearance and remove discoloration, the teeth of specific patients are treated with a variety of bleaching agents. The typical bleaching agents contains carbamide or hydrogen peroxide as the active component. The purpose of the review article was to summarize and discuss the available information concerning the effect of peroxide releasing bleaching agent on dental restorative materials and restorations. Information from all original scientific full papers or reviews listed in PubMed or ISI Web Science were included in the review. Bleaching may exert a negative influence on restorations and restorative materials. Advice is provided based on the current literature to minimize the impact of bleaching treatment on restorative materials and restorations.

• Journal of Distribution Science
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• v.7 no.3
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• pp.49-69
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• 2009

With the proliferation of electronic commerce, online transactions have become a norm. Its enormous potential, however, can be truly realized if consumers feel comfortable facing invisible sellers over the Internet, a virtual business channel. Trust has been identified as a key component in many e-Commerce studies. The purpose of this study is to find out which factors play a major role in building buyer trust and how the build-up trust affects buyer's purchase intention in online used car transactions. Based on the information asymmetry, TAM (Technology Acceptance Model), and the trust theory, our research model includes factors such as a buyer's propensity-to-trust, institutional characteristics (inspection and warranty policy), word-of-mouth referral, perceived size, and perceived benefits as independent variables. The model also includes trust as a mediate variable, purchase intention as a dependent variable, and perceived quality risk as a moderate variable. The research model is tested by analyzing 448 sample data gathered from used car websites. The result shows that the trust has significant effects on the online purchase intention, and institutional characteristics have been identified as one of the most significant factors for trust building in used car websites. For those who perceive quality risk high, actual purchasing behavior occurs only when they have trust on the used car websites, indicating that trust plays a vital role as a mediate variable. This study suggests that buyer trust on the used car websites is important to increase buyer's online purchase behavior.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.11
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• pp.779-789
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• 2014

Cognitive radio (CR) technology based on geo-location database access approach and/or wideband spectrum sensing approach is absolutely vital in order to recognize available frequency bands in white spaces (WSs), and efficiently utilize shared spectrums. This paper presents a new structure for the TVWS database access protocol implementation based on Internet Engineering Task Force (IETF) Protocol to Access WS database (PAWS). A wideband compressive spectrum sensing (WCSS) scheme using a modulated wideband converter is also proposed for the TVWS utilization. The developed database access protocol technology which is adopted in both the TV band device (TVBD) and the TVWS database operates well in the TV frequency bands. The proposed WCSS shows a stable performance in false alarm probability irrespective of noise variance estimation error as well as provides signal detection probabilities greater than 95%. This paper also investigates Federal Communications Commision (FCC) regulatory requirements of TVWS database as well as European Telecommunications Standards Institute (ETSI) policy related to TVWS database. A standardized protocol to achieve interoperability among multiple TVBDs and TVWS databases, which is currently prepared in the IETF, is discussed.

• Korean journal of communication and information
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• v.67
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• pp.152-176
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• 2014

Public opinion has dramatically shifted from positive to negative in Korea society especially since the IMF crisis. Such terms as 'aristocratic union', 'collectivism', 'damages on public interest' became a kind of conventional wisdom. Undoubtedly, media's representation has much to do with such a tantamount difference. This study thus attempts to understand the mechanism by analyzing media discourse related to labor strikes. For this purpose, this paper made a choice three cases including doctor-pharmacist dispute, general strike by truckers' solidarity, and Ssangyong Motor's strike. Total 217 editorial pieces of , and conceived to be a representative newspaper of ideological stance were analyzed. Research showed that while paying particular attention to demoralizing labor strikes, shed positive light on such disputes by articulating fundamental causes hampered by pro-capital policies along with anti-labor law enforcement. The believed to be relatively a neutral one showed ambivalent attitudes toward those cases. More favorable and inclusive reporting were found in accordance with policy shifts as well. Media's selective partisanship for the sake of private interests is firmly believed to downgrading credibility on Korean journalism. Also is fair, balanced and less biased reporting over socal disputes a vital part in crystallizing social consensus. In this consideration, the authors hoped this study to provide an opportunity to contemplate on what would be desirable journalistic values in modern democracy.

• Journal of the Korea Society of Computer and Information
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• v.16 no.12
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• pp.187-196
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• 2011

Induction motors play a vital role in aeronautical and automotive industries so that many researchers have studied on developing a fault detection and classification system of an induction motor to minimize economical damage caused by its fault. With this reason, this paper extracts robust feature vectors from the normal/abnormal vibration signals of the induction motor in noise circumstance: partial autocorrelation (PARCOR) coefficient, log spectrum powers (LSP), cepstrum coefficients mean (CCM), and mel-frequency cepstrum coefficient (MFCC). Then, we classified different types of faults of the induction motor by using the extracted feature vectors as inputs of a neural network. To find optimal feature vectors, this paper evaluated classification performance with 2 to 20 different feature vectors. Experimental results showed that five to six features were good enough to give almost 100% classification accuracy except features by CCM. Furthermore, we considered that vibration signals could include noise components caused by surroundings. Thus, we added white Gaussian noise to original vibration signals, and then evaluated classification performance. The evaluation results yielded that LSP was the most robust in noise circumstance, then PARCOR and MFCC followed by LSP, respectively.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.10
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• pp.123-130
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• 2016

High-frequency induction heating equipment can heat the metal by applying a High-Frequency power to the resonant circuit. The resonance circuit is composed of the work coil and the conduction-cooled power capacitor, it influences the performance of the heat treatment equipment according to the characteristics of the capacitor. However, dependence on conduction-cooled power capacitor's import is high due to lack of core technology research and development. Minimizing the generation of internal heat transmitted inside during LC resonance, reduce the reactive power loss, there is a need for a capacitor within the voltage characteristic outstanding. To implement localization it is vital that prior study of the analysis on the frequency response characteristic for the finished capacitor advanced manufacturer be implemented. Studying the interpolation method to read the value at any point of the characteristic curve for a given log-log scale was applied to the analysis tool of the capacitor by my proposed algorithm. The simulation for reproducing frequency response curves was attempted by assuming a capacitor in a simplified series equivalent RC circuit to obtain the equivalent series resistance value. It was confirmed that the reproduction rate was the result value above 83% as compared to the simulation of the properties and characteristics on the actual reactive power for Peak value, and that the algorithm can be applicable when analyzing and predicting the characteristic curves of a simpled model capacitor.

• Journal of Distribution Science
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• v.10 no.7
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• pp.5-11
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• 2012

The core objective of this research article is to investigate different challenges and opportunities in management as well as start-ups of small businesses in India. The prudence behind this research is to examine various problems in front of the small businesses and to offer vital support and cooperation to overcome those with the support of concerned institutions through consultancy and training programs. The researchers have an intention to make available the research results to the governmental agencies, concerned small business institutions and also to the educational institutions which are continually design plans, programs, policies and strategies to upgrade the managerial and technical dexterities of the small business Indian operators. After thorough revision of relevant literature on small businesses and its management, the researchers used a well structured questionnaire and in-depth personal interviews with 586small business operators selected from manufacturing, trading (retailing and wholesaling), finance, servicing/repair businesses which are located in the coastal districts of Andhra Pradesh in India. The researchers have used convenience sampling and collected data was analyzed with the support of Microsoft Excel and frequency distribution. Noticeably, majority of the small businessmen in India are facing myriad number of challenges both in management and at the time of establishment of their business operations. In particular, 72.47 percent of small businesses operators' have substantiated their strong opinion towards the challenges they are facing particularly finance, marketing and other problems while managing their businesses. The researchers also attempted to get the opinions on problems of the various categories of small businesses while starting their operations. A staggering 68percent of respondents identified the problems related to preparation of business plan, location selection, marketing and other problems like lack of proper credit facilities, skilled manpower, and other infra related problems while setting up of their businesses. On an average, 64.62 and 63.51 percent of small businesses are facing various kinds of problems both at the time of day-to-day management as well as start-up of their businesses respectively. The present research confined with the opinions of only four categories of small business operators particularly from the manufacturing, finance, trading (retailing and wholesaling), and servicing/repair which are continuing their business operations from the nine coastal districts of Andhra Pradesh in India. The present study emphatically provides concrete information required to the business community for identifying an assortment of challenges faced by different small business operators in managing and at the time of their inception. This research paper is first of its kind from this part of the world by offering extensive and credible information required for prospective entrepreneurs in facing the dynamic challenges in managing their business. Furthermore, this research presents invaluable inputs to the stakeholders like all types of governments, policy makers, practitioners, researchers, and educators' about the various impediments faced by the small business community in India.

• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.133-160
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• 1973

1. Introduction Community medicine with the concept of comprehensive medical care and an ideal medical care delivery system not only for an individual or family but for the whole community has emerged. In April 1970, the Presbyterian Medical Center started a hospital based community health service project in order to improve the health of the people in rural areas. Prior to commencing a comprehensive medical care system, a family survey was needed. The major objective of this survey was to obtain information concerning the people and their environment so as to be able to plan and implement a comprehensive medical care program in Soyang-Myun. 2. Survey Method An interview using a family record form was carried out for each household. This family record form was designed to get information about demography, family planning, environmental sanitation and vital statistics. Prior to beginning, the members of the survey team were trained in interviewing techniques for three days. The team consisted of a public health nurse, four nurse-aides, a sanitarian and four health extension workers who are working in our project, The survey was carried out during the period November 1971 to March 1972. 3. Project area 1) Population of Soyang-Myun was 11,668; male, 5,962 and female, 5,706. Sex ratio: 104.5. 2) Households : 1,858 3) Family size: The average household consisted of 6.3 persons. 4) Educational level of householder a. Illiterate 13% b. No schooling but able to read 10% c. Preschool children 19% d. Primary school 47% e. Middle school 7% f. High school 3% g. College or University 1% 5) Occupational distribution of householders a. Farmer 67% b. Laborer 13% c. Office worker 4% d. Merchant 4% e. Industrial worker 2% f. Unemployed 8% g. Miscellaneous 2% 6) Religious affiliation a. No religion 74% b. Buddhist 12% c. Protestant 10% d. Catholic 4% 4. Survey results Living Environment : a. Home ownership 95% b. Kinds of roofing Straw-thatched house 84% Tile-roofed house 10% Slate-roofed house 5% Other 1% c. Floor space Less than 6 pyong 10% 6-10 pyong 53% 11-15 pyong 24% 16-20 pyong 9% More than 20 pyong 4% d. Radio ownership 80% Environmental Sanitation : a. the source of drinking water public well 49% private well 30% drainage water 9% steam water 8% well pump 3% water distribution system 1% b. Distance between well and toilet more than 16meters 38% 6-10 meter 31% 11-15 meters 14% Less than 6 meters 17% c. The status of well management Bad 72% Fair 26% Good 2% d. General sanitary state of house Bad 37% Fair 51% Good 12% e. House drainage system had no house drainage. 77% Family Planning : a. 24% of the people have used contraceptives, but 12% ceased to use them. 76% have never used contraceptives. b. used methods 1oop 68% oral pill 16% vasectomy 4% condom 1% tubal ligation 1% two or more methods 10% Maternal Health : a. The number of conceptions of housewives under 50 years of age. 11 times 26% 6 times 11% 5 times 11% 4 times 9% b. The place of delivery own house 88% hospital 1% others 11% Treatment of general sickness : a. The place of treatment Soyang Health Center 31% Hospital (private or otherwise) 26% Pharmacy 14% Herb medicine 5% Private care 5% No treatment 12% Miscellaneous 7% b. Usual causes of diseases Unknown 46% Tuberculosis 29% Neuralgia 8% CVA 3% Bronchitis 3% Others 11%

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.3
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• pp.181-188
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• 2020

Purpose : The purpose of this study is to compare the effects on abdominal muscle thickness and breathing by applying trunk strength exercise and deep stabilization exercise along with breathing exercise, which is the main respiratory muscle during breathing, to present an efficient exercise method with diaphragm breathing. Methods : This study was performed on normal 6 females and 14 males subjects. They were divided into 2 groups which trunk strength exercise and deep stabilization exercise group. The trunk strength exercise group (TSE) attended prone press-up, crunch and pelvic tiling. The deep stabilization exercise group (DSE) attended abdominal drawing, horizontal side-support and bridging exercise. Breathing exercise was performed for each set break time for 1 minute. Results : First, in the comparison of the change in the thickness of the abdominal muscle between the trunk strength training group and the deep stabilization group before and after exercise, there was a statistically significant difference in the comparison of transverse abdominis (TrA), rectus femoris (RF), external oblique (EO), internal oblique (IO) (p<.05). However, there was no significant difference in any comparison between groups (p>.05). Second, in the comparison of changes in respiratory function between the trunk strength exercise group and the deep stabilization exercise group before and after exercise, there were statistically significant differences in the exerted forced vital capacity (FVC), forced expiratory volume at one second (FEV₁), peak expiratory flow (PEF) in the comparison before and after the experiment (p<.05). However, there was no significant difference in any comparison between groups (p>.05). Conclusion : As a result of this study, it can be said that both trunk strength exercises and deep stabilization exercises along with diaphragm breathing are exercises that strengthen deep and superficial muscles, and have a positive effect on breathing function as well as muscle strength. However, it is not known which exercise was more effective, and because it was combined with breathing exercise, the interference effect appeared.