• 한국농공학회논문집
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• 제46권5호
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• pp.155-163
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• 2004

The objectives of this study were to characterize the wastewater flow through the VFS, and relate this to the P removal in the VFS. A total of 68 subsurface wells (20∼40 cm below the soil surface) and 35 surface wells (0~5 cm), and the application of chloride tracer were used to investigate flow paths and soluble reactive P (SRP) removal from the 21 m wide and 33 m long VFS receiving dairy milkhouse waste. The early chloride breakthroughs in wells in the center of the VFS showed that the milkhouse waste flows preferentially down in the center of the hillslope. The locally saturated area created near the discharge pipe in the center of the VFS accelerates surface flow that contributed to rapid transport of P to the down slope area. Although VFS of 33m long eventually reduced SRP to lower than 0.2 mg/L in most cases, SRP is less effectively removed in the areas where soil saturation occurred. It is suggested that the effort to distribute the wastewater uniformly to avoid soil saturation and reduce the flow velocity need to be considered in new designs.

• 한국정보통신학회논문지
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• 제20권5호
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• pp.957-962
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• 2016

현재 지상파 이동 멀티미디어방송(T-DMB)은 국지적인 재난경보 방송을 실시하거나 다양한 방송을 시청할 수 있다. 그러나 전파 음영 지역에는 시설 투자의 한계로 인해 서비스가 제한되고 있는 실정이다. 또한 T-DMB 시청이 불가능한 모바일 디바이스들도 있기에 T-DMB는 제한된 지역과 모바일 디바이스들만 시청할 수 있는 방송이라는 문제점이 있다. 본 논문에서는 T-DMB의 문제점을 해결하기 위한 방법으로 T-DMB 방송을 수신하여 모바일 디바이스로 재전송해주는 시스템을 연구하였다. 이를 통해 T-DMB 수신이 불가능한 모바일 디바이스에서도 방송을 수신하여 시청할 수 있으며 제한수신 기능을 통한 단방향/양방향 인증 메커니즘을 제공하여 등록되어 있는 사용자에 한해서 방송을 시청할 수 있도록 시스템을 구성하였다.

• 방송공학회논문지
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• 제15권6호
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• pp.731-741
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• 2010

본 논문에서는 30 MHz ~ 3000 MHz 대역에서 1 kW ERP에 대해 점-대-지역 전파특성 예측에 이용되는 ITU-R 권고 P.1546 전파 모델을 이용하여 DTV 수신기의 전계강도 예측을 위한 방법을 제안한다. DTV 수신기의 유도된 전계강도 수식과 권고에서 기술된 절차를 이용하여 수치계산을 통한 결과를 제시한다. 또한 산출된 결과의 적절성 검증을 위해 Okumura-Hata 모델과 비교하였으며, 수신 전계강도가 약 6.9 ~ 11.5 % 범위 내에 오차가 있음을 확인할 수 있었다. 제시된 방법은 DTV 수신지역의 전계강도 예측을 통한 송신된 신호의 품질 분석은 물론, 양호한 전파환경 구축을 위한 적절한 국소 선정을 제공한다. 또한 동일 대역의 주파수 공유를 위한 보호비 또는 이격 거리 분석에도 직접 활용이 가능하다.

• 한국콘텐츠학회논문지
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• 제9권2호
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• pp.10-17
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• 2009

본 논문에서는 915MHz 대역 IEEE 802.15.4b LR-WPAN(Low-Rate Wireless Personal Area Network) 비동기 DSSS O-QPSK 기반 수신 시스템의 주파수 옵셋 영향을 분석하고, 차분 필터를 추가 함으로써 주파수 옵셋을 보상할 수 있는 방법을 제시한다. IEEE 802.15.4b 915MHz 규격에서는 DSSS PSSS-ASK 변조방식과 DSSS O-QPSK 변조방식을 채용하여 250kbps의 전송율을 갖는 새로운 방식을 제시하고 있다. 본 논문에서 사용한 DSSS O-QPSK 변조방식은 40ppm(주파수 옵셋 36.6kHz)까지는 BER에 변화가 없으나, 그 이상의 주파수 옵셋이 발생하면 BER이 높아져 안정적인 수신이 어려운 문제가 있다. 이 문제를 해결하기 위해 DSSS O-QPSK 기반 수신기의 상관기에 MDDF(Multiple Delay Differential Filter)를 적용하여 ${\pm}80ppm$에서도 안정적인 수신이 가능함을 보인다. 제안 알고리즘의 성능을 검증하기 위해, 다양한 AWGN 및 주파수 옵셋 환경을 가정한 컴퓨터 모의실험의 결과를 제시하고, 그 유효성을 입증한다.

• 한국전자파학회논문지
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• 제7권3호
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• pp.219-229
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• 1996

육상 이동통신의 서비스 범위 예측에 가장 기본이 되는 전송 손실 계산 방식은 그 적용범위 및 모델도출 방법에 따라 많은 발전을 거듭하여 왔다. 그러나, 전파는 이것이 지나가는 환경, 즉 빌딩의 특성이나, 나무, 그리고 지형형태 등에 의해 너무나 많은 영향을 받으므로 미국,일본 동 외국의 환경에서 만들어져 국내에 도입된 전파 예측모델들은 우리나라의 실정에 적합하지 않는 점이 많다. 본 논문에서는 국내 지형을 분석하여 그 특성에 따라 여섯가지의 종류로 분류하고 각각에 해당하는 국내 지역을 선정하여 무선호출 주파수 대역에서 전계강도 측정을 수행하였다. 또한, 이 측정 데이타를 이용한 실험식과 함께 산악지역에서의 회절 계산식을 포함하여 가시거리 및 비가시거리를 구분하여 전계강도를 계산하는 예측모델을 만들었다. 제안된 모델을 국내 지형 데이타 베이스와 연결하여 전계강도 예측을 수행한 값과 실측된 데이타와 비교한 결과, 최소 3dB에서 최고 9dB 정도로 오차가 나타났으므로 실용성이 있을 것으로 판단된다.

• 한국치위생학회지
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• 제15권3호
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• pp.451-459
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• 2015

Objectives: The objective of this study is to investigate oral health behavior, PHP index and OHIP, awareness, attitude and behavior toward oral health in the foreign factory workers. Thsi study will provide the basic data for the improvement of the foreigners' quality of life. Methods: A self-reported questionnaire was completed by 126 Sri Lankans and 76 Chinese over 20 years old in Daegu and Gyeongbuk from January to April, 2012 through man to man interview after receiving informed consent. The questionnaire included oral health status, PHP index and OHIP. Results: OHIP was closely related to sex, marital status, and medical expense burden. PHP index was closely related to religion and income. The averages of OHP and PHP were 4.36 and 3.7, respectively and very bad. OHIP was influenced by number of toothbrushing, time of toothbrushing, use of oral hygiene device, and dental visit within a year. PHP index was influenced by the area of toothbrushing, time of toothbrushing, and the dental visit within a year. Regression analysis of PHP index according to OHIP and oral care conditions showed the equation. Y(OHIP)=2.999+0.103(area of toothbrushing)+0.346(the use of oral hygiene article)+ 0.077(visiting to the dentist during the past one year)-0.173(PHP index)(p<0.05). Conclusions: Low PHP index in the foreign workers affected quality of life. So the company must provide the continuing oral health care for the foreign workers every year. The concern for the health care for the foreigners will improve oral health behavior in the future.

• 한국물환경학회지
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• 제22권6호
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• pp.1068-1074
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• 2006

For receiving water quality protection a control systems of urban drainage for CSOs reduction is needed. Examples in combined sewer systems include downstream storage facilities that detain runoff during periods of high flow and allow the detained water to be conveyed by an interceptor sewer to a centralized treatment plant during periods of low flow. The design of such facilities as storm-water detention storage is highly dependant on the temporal variability of storage capacity available as well as the infiltration capacity of soil and recovery of depression storage. For the continuous long-term analysis of urban drainage system this study used analytical probabilistic model based on derived probability distribution theory. As an alternative to the modeling of urban drainage system for planning or screening level analysis of runoff control alternatives, this model has evolved that offers much ease and flexibility in terms of computation while considering long-term meteorology. This study presented rainfall and runoff characteristics of the subject area using analytical probabilistic model. Runoff characteristics manifested the unique characteristics of the subject area with the infiltration capacity of soil and recovery of depression storage and was examined appropriately by sensitivity analysis. This study presented the average annual CSOs, number of CSOs and event mean CSOs for the decision of storage volume.

• 한국지역사회생활과학회지
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• 제23권1호
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• pp.61-77
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• 2012

This study was carried out on hospitalized patients receiving diet therapy satisfaction and awareness of nutrition education in small and medium-sized hospitals in southern Gyeonggi area. By the face-to-face interview with questionnaire method, the survey was carried out on 150 subjects (99 males and 51 females). The patients (64.7% of males, 52.9% of females) heard the description of diet therapy without the aid of written manual. Patients were moderately satisfied by food that was rated based on these indicators: tastiness (2.45), saltiness (2.23), smelliness (2.23), and appetizing appearance (2.39) as a 4 point scale. Most of the patients (80.8% of males, 69.8% of females) wanted to continue diet therapy. The importance of diet was correlated with the tastiness, saltiness, and appetizing appearance of diet. And the help of dietitians' explanation was correlated with appetite. 55.6% of males and 35.4% of females received nutrition education before (p<0.05). The number of times nutrition education was received was once for male (33.3%) and three times for female (44.4%). Most nutrition education satisfaction that was calculated on a 4 point scale was well understood (3.03), recognized importance (3.44 for males, 2.78 for females) and help for disease management (p<0.01). Also they were satisfied with the explanation of disease (3.20). Nutrition education satisfaction was correlated positively with explanation about food related to disease, the current dietary treatment, how to prepare diet recipes, and dietitian's kindness, but negatively with satisfaction with explanation of diet therapy, and the description and help for disease management. In conclusion, the most important factor in practicing diet therapy was meeting with the dietitian. Intensive nutrition education after the patient's discharge is necessary for patients to continue diet therapy.

• 산경연구논집
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• 제8권5호
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• pp.77-85
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• 2017

Purpose - The purpose of this study is to investigate the variables that lead consumers to visit traditional markets and buy market goods. Thus, the current research examined the relationship between satisfaction and return intention as among the factors influencing loyalty. Research design, data, and methodology - This study was conducted to examine the effects of the perceived level of factors on loyalty and how it influenced consumers' visits to traditional markets in 125 adult adolescents and women living in Mok-po area. The results of the questionnaire were obtained. The statistical data of the questionnaire were verified by SPSS. Results - In this study, consumers' perception level of eight loyalty factors can be perceived by the traditional Korean market. The empirical analysis is summarized as follows. First, by selecting five representative variables influencing intention to return to traditional markets, Mok-po area consumers were affected by the intention to revisit according to the intensity of recognition level among these variables. Second, the higher the perceived level of product price, quality of access (accessibility) among the factors that consumers perceive as important factors in visiting traditional markets were heightened. Third, Mokpo residents are aware of the main important factors of visiting the market such as receiving a friendly atmosphere (image) about traditional market, market environment (hygiene and cleanliness), connection with the local economy, and customer service such as kindness, refund and return. These loyalty factors did not affect consumers' intention to revisit. In other words, image, environment, regional economic linkage, and these factors did not have a positive effect on revisit intention. Conclusions - The empirical analysis of this study suggests that factors that directly affect loyalty among the key factors that play a major role in visiting traditional markets should be identified and developed as loyalty factors. It is necessary to identify the key factors influencing the satisfaction and loyalty of traditional market users, and operate a system that systematically and comprehensively manages and evaluates them. In order to do this, the government, the local governments, and related organizations should regularly conduct loyalty and satisfaction surveys on visa recognition levels and establish strategies for dramatic improvement measures.

• 대한통합의학회지
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• 제5권3호
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• pp.29-37
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• 2017

Purpose: The purpose of this study was to classify patients with chronic back pain according to the degree of their back pain, and to compare the pain dysfunction index with the qualitative changes in abdominal muscles. Therefore, we aimed to provide a basis for the treatment intervention method for patients with back pain. Methods: Twenty patients with chronic back pain were purposive sample to a group of 10 patients with a back pain index of 60 % or more and a group with less than 60 % of back pain, and the subjects who voluntarily participated in the study After receiving the letter, I conducted the research the dysfunction of back pain was measured by the Korean version of the Oswestry Disability Index (KODI), and the ultrasonic wave (Ultrasound MyLabOne, ESAOTE, Italy) And the white area index, and the abdominal muscle movement was used as the exercise instrument POWER breathe K5 (Hab direct, UK), which strengthens the respiratory muscles through threshold-muscle traction. Result: In this study, patients with chronic back pain were subjected to breathing exercises, which led to the decrease in back pain dysfunction. The ultrasonographic analysis of abdominal muscles revealed that both the white area index and muscle image density in the skeletal muscle and in the outer muscle of the abdomen gradually decreased over time. Conclusion: It is thought that introducing back pain patients to abdominal muscle reinforcement training is effective in improving the functions of the patients' muscles, thus increasing their quality of life.