• 대한전자공학회논문지TC
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• 제46권2호
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• pp.46-52
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• 2009

본 논문에서는 직교 주파수 분할 다중 접속 방식(Orhogonal Frequency Division Multiple Access) 상향 링크 시스템에서 best linear unbiased estimator (BLUE)의 원리에 기반한 시간 동기 추정 알고리즘을 소개하며, 이 알고리즘을 기반으로 하여, 추정범위 제한 문제를 해결하기 위한 개선된 시간추정 기법을 추가적으로 제안한다. 새로운 추정 알고리즘은 인접한 부반송파 간의 차등 상관관계를 이용하여 주파수 축에서 시간 오차를 추정한다. 차등 상관관계는 시간 오차를 포함한 위상 정보를 나타내고, 채널의 주파수 선택적 특성에 의한 신호 왜곡을 완화시킨다. 기존의 추정 방법과 비교하여 제안된 추정 알고리즘은 비교적 정확한 추정 성능을 보인다. 실험 결과는 제안된 추정기가 상대적으로 작은 오차의 평균과 분산을 가지는 것을 확인하여 준다. 또한 실험은 신호 대 잡음비의 크기가 0에서 20 dB 사이일 때, 시간 추정 오차에 의한 제안된 추정기의 신호 대 잡음비 열화 정도가 0.4 dB 이하인 것을 보여준다. 따라서 제안된 동기 알고리즘은 OFDMA 상향 링크 시스템에서 다중 사용자의 시간동기추정에 적합하다.

• 대한한의학회지
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• 제38권4호
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• pp.55-61
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• 2017

Objectives: In order to accurately measure skin moisture and accumulate normal skin moisture data, analyzing the uncertainty of the skin moisture measurement and establishing standard reference data is essential. It helps to evaluate the skin's condition and has great significance in diagnosis and treatment. In this study, the traceability of the equipment and the uncertainty of the results were analyzed for their potential use in the field of Korean medicine. The data was collected measuring skin moisture on the sole of the foot. Methods: One professional measured the moisture of the adult male's foot 10 times following a determined protocol. The standard uncertainty of repeated measurements was calculated from the mean value of 10 repeated measurements. Ten trainee participants also measured the adult male's foot following a determined protocol. The standard uncertainty by tester was calculated from the value of repeated measurements. Results: As a result of analyzing the difference between the mean and standard uncertainties in both the expert and trainees, it was confirmed that the variance in this study did not satisfy the normal distribution. In addition, the Mann-Whitney U-test was carried out, and it was found that there was no significant difference in the measured values of the two groups. The authorized uncertainty of measurements and traceability of all the equipment was not confirmed. Conclusions: This paper establishes the basis for later measurement-equipment research to provide the objective indicators to approach the dryness of plantar skin from dehydration, the Korean medicine perspective.

• 구강회복응용과학지
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• 제19권1호
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• pp.27-33
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• 2003

Excessive heat generation at the implant-bone interface may cause irreversible bone damage and loss of osseointegration. The effect of heat generation in vitro at the implant surface caused by abutment reduction with high-speed dental turbine was examined. Titanium-alloy abutments connected to a titanium alloy screw-implant embedded in an acrylic-resin block in a $37^{\circ}C$ water bath were prepared. Temperature changes were recorded via embedded thermocouples at the cervix and apex of the implant surface. Analysis of variance for repeated measures was used to compare seven treatment groups. Fifty seconds of continuous cutting with air and water coolant caused a mean temperature increase of $1.24^{\circ}C$ at apex and $5.77^{\circ}C$ at cervix. Similar intermittent cutting caused increase of $2.50^{\circ}C$ at apex and $1.64^{\circ}C$ at cervix. But, continuous cutting with air coolant caused a mean temperature increase of $6.47^{\circ}C$ at apex and $5.77^{\circ}C$ at cervix. Similar intermittent cutting caused increase of $6.47^{\circ}C$ at apex and $5.77^{\circ}C$ at cervix. Preparation of implant abutment does not lead to detrimental effect on peri-implant tissues provided that adequate cooling. However, without water cooling, extreme overheating could be provoked, reaching the critical temperature that would lead to irreversible bone damage within only a few seconds.

• 구강회복응용과학지
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• 제27권1호
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• pp.25-39
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• 2011

마그네슘 양극산화 임플란트는 동물실험에서 우수한 골반응을 나타내었지만 이에 대한 임상 연구는 전무하다. 본 연구에서는 마그네슘 양극산화 임플란트의 단기간 성공률 및 안정성, 변연골 흡수량을 평가하고자 하였다. 강릉원주대학교 치과병원의 임상시험위원회의 승인을 거쳐 건강한 부분 무치악 환자에게 마그네슘 양극산화 임플란트를 식립한 후 일반적인 프로토콜에 따라 보철 치료를 시행하였다. 1차 수술, 2차 수술, 보철물 시적, 하중 후 1개월, 3개월, 6개월 평가를 시행하였으며, 매회 내원 시 임플란트 안정지수(Implant stability quotient, ISQ)를 측정하고 구내 치근단 방사선 사진에서 변연골 흡수량을 산출하였다. 반복측정이 있는 분산분석법을 이용하여 통계적 분석을 시행하였다. 총 50명에게 식립된 101개의 임플란트 중 골유착에 실패한 임플란트는 없었으며, 하중 후 6개월 성공률은 100%였다. 평균 ISQ는 시간이 경과함에 따라 증가하였으며 여성보다 남성에서, 상악보다 하악에서 높게 나타났다 (P<.05). 하중 6개월 후 골질이 양호할수록, 고정체 직경이 클수록 높은 ISQ 값을 보였다 (P<.05). 하중 후 6개월간 평균 변연골 흡수량은 0.26 mm로 관찰되었으며 하악보다 상악에서, 여성보다 남성에서 더 많은 흡수가 관찰되었다. 본 연구의 마그네슘 양극산화 임플란트의 6개월 성공률은 100%이며, 낮은 골질에서도 우수한 골유착이 관찰되었다. 안정성과 변연골 수준 또한 만족스러운 결과를 보였지만 더욱 장기적인 임상연구가 필요하다고 사료된다.

• The Journal of Advanced Prosthodontics
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• 제1권2호
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• pp.85-90
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• 2009

STATEMENT OF PROBLEM. Over the years, resin-bonded fixed partial dentures (RBFPDs) have gone through substantial development and refinement. Several studies examined the biomechanics of tooth preparation and framework design in relation to the success rate of RBFPDs and considered retention and resistance form essential for increase of clinical retention. However, these criteria required preparations to be more invasive, which violates not only the original intentions of the RBFPD, but may also have an adverse effect on retention due to loss of enamel, an important factor in bonding. PURPOSE. The object of this in vitro study was to compare the dislodgement resistance of the new types of RBFPDs, the conventional three-unit fixed partial denture, and conventional design of RBFPD (Maryland bridge). MATERIAL AND METHODS. Fifty resin mandibular left second premolars and second molars were prepared on dentiforms, according to the RBFPD design. After model fabrication (five group, n = 10), prostheses were fabricated and cemented with zinc phosphate cement. After cementation, the specimens were subjected to tensile loading at a cross head speed of 4 mm/min in a universal testing machine. The separation load was recorded and analyzed statistically using one-way analysis of variance followed by Duncan's multiple range test. RESULTS. Group V, the pin-retained RBFPDs, had the highest mean dislodgement resistance, whereas specimens of group II, the conventional RBFPDs, exhibited a significantly lower mean dislodgement resistance compared to the other 4 groups (P <.05). There were no significant differences between group I, III, and IV in terms of dislodgement resistance (P>.05). Group V had the highest mean MPa (N/$mm^2$) (P <.05). There was no significant difference between groups I, II, III and IV (P > .05). CONCLUSION. Within the limits of the design of this in vitro study, it was concluded that: 1. The modified RBFPDs which utilizes the original tooth undercuts and requires no tooth preparation, compared with the conventional design of RBFPDs, has significantly high dislodgement resistance (P < .05). 2. The modified RBFPDs which utilizes the original tooth undercuts and requires minimal tooth preparation, compared with the conventional FPDs, has significantly no difference in retention and dislodgement resistance)(P>.05). 3. The pin-retained FPDs showed a high dislodgement resistance compared to the conventional three-unit FPDs (P<.05).

• 한국산학기술학회논문지
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• 제15권7호
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• pp.4318-4328
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• 2014

본 연구는 임상간호사의 감정노동, 직무 스트레스와 섭식태도의 정도를 파악하고 이들 간의 관련성을 파악하는 연구이다. 자료수집은 2013년 2월 21일부터 3월 31일까지이며 G시의 2개 대학병원의 간호사 434명을 대상으로 하였고 자료분석은 SPSS 17.0 프로그램을 이용하여 분석하였다. 임상간호사의 감정노동, 직무 스트레스와 섭식태도의 평균 평점은 3.53, 3.81 그리고 2.27 이었다. 감정노동은 직무스트레스((r= .570, p=<.001), 섭식태도(r= .114, p=.05)와 통계적으로 유의한 정의 상관관계가 있었다. 또한 섭식태도에 가장 큰 영향력을 미치는 요인으로는 BMI(${\beta}$=262, p<.001), 체중감량 운동을 하는 경우(${\beta}$=.203, p<.001)였으며 그다음은 특수부서 대비 내과계 병동(${\beta}$=178, p<.001), 외과계 병동(${\beta}$=.102, p=.043), 감정노동(${\beta}$=106, p=0.49)이었으며, 이 변수는 섭식태도를 16.8% 설명하였다. 따라서 섭식태도를 개선하기 위한 BMI별, 근무부서별 차별화된 관리와 프로그램이 필요할 것으로 사료된다.

• 품질경영학회지
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• 제35권2호
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• pp.37-44
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• 2007

Today, the statistical process control (SPC) in manufacture environment is an important role at the process by the productivity improvement of the manufacturing systems. The control chart in this statistical method is widely used as an important statistical tool to find the assignable cause that provoke the change of the process parameters such as the mean of interest or standard deviation. But the traditional SPC don't grasp the change of process according to the points fallen the near control limits because of monitoring the variance of process such as the fixed sampling interval and the sample size and handle the cost of the aspect of these sample point. The control chart can be divided into the statistical and economic design. Generally, the economic design considers the cost that maintains the quality level of process. But it is necessary to consider the cost of the process improvement by the learning effects. This study does the economic design in the VSI $\bar X$ control chart and added the concept of loss function of Taguchi in the cost model. Also, we preyed that the VSI $\bar X$ control chart is better than the FSI $\bar X$ in terms of the economic aspects and proposed the standard of the process improvement using the VSI $\bar X$ control chart.

• 여성건강간호학회지
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• 제4권2호
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• pp.231-244
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• 1998

The purpose of this study was to provide a basis for nursing intervention to enhance quality if life in women having hysterectomies. Data was collected using a self-report questionnaire from 205 women having hysterectomies at the outpatient clinics of four general hospitals and a mail survey in Pusan City. Reliability of eight instrument's was tested with Cronbach's alpha which ranged from .601-.901. The data were analyzed by percentage, mean, SD, Pearson's Correlation and Stepwise Multiple Regression by using the SPSS 7.5 WIN Program. The results are as follows: 1) The average score for the quality of life was 74.33(score range 23-92). 2) There was a significant correlation between the predictive variables on quality of life. The most significant correlation was sexual identity(r=.516, p=.000). 3) When quality if life score was entered into the equation as the dependent variable, 7variables explaining 54.5% of the variation in quality if life score. Sexual identity was the main predictor of quality of life and accounted for 24.6% of the variance in quality of life. 4) When physical domain score was entered into equation as the dependent variable, 5variables explaining 29.2% of the variation in physical domain score. 5) When psychological domain score was entered into the equation as the dependent variable, 5variables explaining 46.0% of the variation in psychological domain score. 6) When sexual life domain score was entered into the equation as the dependent variable, 6variables explaining 39.4% of the variation in sexual life domain score. In conclusion, sexual identity, pre-operational symptom, sense of loss, spouse's support, age, professional support, coping behavior were identified as important variables in the quality of life in women having hysterectomies.

• 동력기계공학회지
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• 제12권1호
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• pp.13-19
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• 2008

In this study, a variable induction and exhaust system is applied to turbocharged diesel engine to improve the volumetric efficiency, especially, in a low and transient engine speed range where much of the pollutant matters are expelled out. The volumetric efficiency is known as one of the most important factor which affects significantly engine performance, fuel economy and further emission and noise level. As the torque increase with the engine speed up, the gas flow in an exhaust pipe become pulsating and then has an effect on boost up capacity of air charging into the cylinder and expelling capacity to atmosphere simultaneously. But at a low and idling speed, the pulsation effect was not so significant. Accordingly, resonator was employed to compensate their loss. The variable induction system consists of the secondary pipe, resonator, intercooler, and torque variance were examined with extended operating conditions. In the mean time, for interpretation and well understanding for the phenomena of wave action that arising during intake and exhaust process between turbocharger and variable intake system, the concept of the combined supercharging was introduced. Some of results are depicted which deal with a pressure history during valve events of induction process. Consequently, by the governing of these phase and amplitude of pulsating wave, it enables us to estimate and evaluate for the intake system performance and also, designing stage of the system layout.

• PNF and Movement
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• 제20권2호
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• pp.167-177
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• 2022

Purpose: Pes planus is a common foot deformity that involves the loss of the medial longitudinal arch. The medial longitudinal arch deformity is usually asymptomatic; however, it can lead to an increased risk of pain and injury. Low-Dye taping is designed to treat plantar heel pain and pes planus. However, low-Dye taping is relatively complex, and a considerable amount of time is required to apply the tape correctly. The purpose of this study was to compare the acute effect of two different types of taping (low-Dye taping and modified Mulligan taping) on arch reformation, plantar pressure, and gait characteristics in participants with asymptomatic flexible pes planus. Methods: Twenty subjects (9 males and 11 females; mean age = 21.95 years) with asymptomatic flexible pes planus voluntarily participated in this study. Arch reformation was evaluated using navicular height measurements. Changes in plantar pressure distribution were measured using BioRecue equipment. Gait parameters were measured using spatiotemporal data collected during consecutive gait cycles using a G-WALK device. One-way analysis of variance was used to compare the three different conditions (i.e., bare foot, low-Dye taping, and modified Mulligan taping) for each variable. Results: Navicular height was significantly increased in subjects who underwent the two types of taping compared to those who experienced the bare foot condition. The plantar pressure was significantly shifted to the posterolateral area after modified Mulligan taping compared with the bare foot condition. There were no significant differences in the gait parameters. Conclusion: The findings of this study indicate that modified Mulligan taping has a similar effect to low-Dye taping, and modified Mulligan taping is a simpler method than low-Dye taping.