• Journal of Biosystems Engineering
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• 제17권4호
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• pp.344-353
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• 1992

This study was carried out to develop a fully-controlled plant growth system for studying the effects of environmental factors on plant growth. The plant growth system consists of the growth chamber, the measurement system for sensing and signal conditioning the environmental factors and the control system which includes control algorithm required for optimum operation and on-line monitoring. The results of the study on the performance of the controlled plant growth system are summarized as follows : 1. Under the light intensity of 18,000~20,000 lux, the temperature was controlled in the range of $22{\pm}0.4^{\circ}C$, the relative humidity of $70{\pm}5%$ respectively. 2. The $CO_2$ concentration was controlled in the range of $1,000{\pm}40ppm$(from 1st to 4th day) and $1,500{\pm}40ppm$(from 4th to 9th day). 3. The electric conductivity(EC) and pH of the nutrient solution were controlled in the range of $1.9{\pm}0.2mS/cm$ and $6.8{\pm}0.5pH$ respectively. 4. Under the above environmental conditions, the average fresh weight of leaf lettuce increased from 10g to 74g in 9 days with 24 hour lighting.

• Journal of Pharmaceutical Investigation
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• 제29권4호
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• pp.343-348
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• 1999

The purpose of this study is to prepare the controlled release adhesive patch containing naproxen. Pressuresensitive adhesive (PSA)-type patch was fabricated by casting of polyisobutylene (PIE.) and mineral oil in toluene. Membrane-controlled release (MCR)-type patch was prepared by the attachment of the controlled release membrane on the PSAtype patch. The membrane was mainly composed of Eudragit, polyethylene glycol(PEG) and glycerin. The drug release profile and skin permeation test with various patches were evaluated in vitro. The release of naproxen from PIE-based PSAtype patch with various loading doses fitted Higuchi's diffusion equation. However, the permeation of naproxen through hairless mouse skin from PSA-type patch followed zero-order kinetics. In MCR-type patch, thickness of controlled release membrane affected on the drug release rate highly. In the composition of membrane, the release rate was decreased as the ratio of Eudragit increased. The drug release from the MCR-type patch followed zero order kinetics. The permeation of naproxen through hairless mouse skin from MCR-type patch showed lag time for the intial release period and didn't fit the zero-order kinetics

• 대한치과마취과학회지
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• 제6권2호
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• pp.98-102
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• 2006

The purpose of this study was to evaluate the difference on pain intensity and discomfort between pressure-controlled injection system and conventional syringe injection technique from the patients undergoing oral and maxillofacial surgery. In a prospective, randomized, case-controlled study, 60 patients were divided into two groups (n=30 in each). In experimental group, pressure-controlled injection system was applied. In control group, conventional syringe injection system was applied. Pain rating score (PRS) and visual analogue scale (VAS) were assessed. The average of VAS in experimental group ($16.67{\pm}15.07$) was smaller than that of control group ($25.63{\pm}22.21$), though there were no significant differences (P=0.072). In PRS, fifteen patients (50.0%) of experimental group answered that they experienced mild pain. However sixteen patients (53.3%) of control group answered that they experienced intermediate pain. From the results, pressure-controlled injection system may be an effective method to reduce pain during the dental local anesthetic procedure.

• 한방재활의학과학회지
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• 제21권4호
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• pp.77-86
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• 2011

Objectives: This study aims to evaluate domestic clinical studies related to the exercise program targeting farmers. Methods: Five Korean databases were seamed for prospective clinical trials of exercise program targeting farmers from 2001 to August, 2011. Only studies conducted in Korean language were searched. Results: Thirteen clinical studies were included among 3374 studies searched. Six were observational studies, four were non-randomized controlled trials, and three were randomized controlled trials. All of included studies reported favorable effects of exercise group compared to baseline of controlled group. Conclusions: We found various mistake in the applications of statistical methodologies in the studies of exercise program targeting farmers. It is necessary for more randomized controlled trials to evaluate effect of exercise program target farmers.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.363-368
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• 2021

This study attempts to examine whether ownership of government-controlled corporations and audit committee effectiveness are related. The population of this study is 431 listed manufactured firms in the Saudi Stock Exchange (Tadawul) for the period 2012-2019 that published their financial and annual reports for the period 2012-2019. This population criterion is based on considerations that manufacturing companies listed on Tadawul have publicly accessible data and they have greater obligations to implement corporate governance code. Using the complementary hypothesis, this study predicts that there is a positive relationship between the ownership of government-controlled companies and audit committee effectiveness. The Pooled OLS regression shows that government-controlled companies' ownership is positively associated with audit committee effectiveness. Our study also indicates that ownership of government-controlled companies as a governance monitoring mechanism becomes more effective as it is combined with audit committee effectiveness which is another governance monitoring mechanism. The results of this study provide insightful evidence to policymakers at the company and country levels on the relationship of government-corporate ownership and audit committee effectiveness.

• 대한교통학회지
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• 제21권5호
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• pp.31-40
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• 2003

우리나라의 비신호교차로의 유형은 양방향정지식과 무통제식으로 분류될 수 있다. 무통제식은 국내외에서도 용량이나 서비스수준 분석에 관한 연구가 거의 전무하다. 본 연구에서는 이러한 유형의 무통제 교차로의 서비스 수준을 분석할 수 있는 방법론을 개발하는 것을 목표로 하였다. 우선 무통제 교차로의 서비스수준을 평가할 수 있는 효과척도 선정을 위한 분석을 수행하였다. 교통량, 상충횟수, 교차로 통행시간(지체) 등을 분석한 결과, 상충횟수과 교통량이 선형의 관계를 가지고 있는 것으로 나타나 이 2가지를 효과척도로 선정하였다. 서비스수준 E와 F의 경계가 되는 교통량(용량)은 1985 USHCM의 전방향정지식 교차로의 용량을 참고로 2000대/시로 하였으며 이때 상충횟수는 300회가 된다. 그리고 서비스수준별 상충횟수와 교통량을 용량상태를 기준으로 비례적으로 배분하였다. 교차로 총교통량으로 서비스수준을 결정할 때. 방향별 교통량비가 상충횟수에 영향을 주는 것으로 분석되어 방향별 교통량비에 대한 서비스 교통량을 보정하는 방법을 제안하였다.

• 한국약용작물학회지
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• 제24권4호
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• pp.277-283
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• 2016

Background: The photosynthetic efficiency cool-season, semi-shade ginseng is normal at low morning temperatures, but drops at high afternoon temperatures. Therefore, optimal plant performance would be ensured if it were possible to control daily light transmission rates (LTR). Methods and Results: Plants were grown in a controlled light environment that replicated 11 AM conditions and comparatively analyzed against plant grown under normal conditions. Growth in the controlled light environment resulted in a 2.81 fold increase in photosynthetic efficiency with no change in chlorophyll content, although LTR were high due to low morning temperatures. Increased aerial plant growth was observed in the ginseng plants adapted to the controlled light environment, which in turn influenced root weight. An 81% increase in fresh root weight (33.3 g per plant on average) was observed in 4-year-old ginseng plants grown in controlled light environment compared to the plants grown following conventional practices (18.4 g per plant on average). With regard to the inorganic composition of leaves of 4-year-old ginseng plants grown in controlled light environment, an increased in Fe content was observed, while Mn and Zn content decreased, and total ginsenoside content of roots increased 2.37 fold. Conclusions: Growth of ginseng under a favorable light environment, such as the condition which exist naturally at 11 AM and are suitable for the plant's photosynthetic activity creates the possibility of large scale production, excellent-quality ginseng.

• Clinics in Shoulder and Elbow
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• 제19권4호
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• pp.192-196
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• 2016

Background: This study investigated the efficacy and safety of combined subacromial and intravenous patient-controlled analgesia for control of postoperative pain after arthroscopic rotator cuff repair. Methods: Between May 2012 and August 2014, 60 patients who underwent arthroscopic rotator cuff repair with acromioplasty and received patient-controlled analgesia were studied prospectively. Cases were divided into 2 groups: combined subacromial and intravenous infusion group (group A, 30 cases) and solitary intravenous infusion group (group B, 30 cases). The visual analogue scale was used to record the patient's level of pain every 12 hours during postoperative 72 hours and the following 48 hours after the suspension of patient-controlled analgesia. Results: The mean preoperative visual analogue scale score was 7.8 in group A and 7.6 in group B, and the immediate postoperative visual analogue scale score was 7.9 and 8.1 for each group. At postoperative time (From 12 hours to 72 hours after operation), the scores of combined subacromial and intravenous infusion were significantly lower than those of solitary intravenous infusion. Significant difference in the frequency of supplemental analgesic injections was observed between group A and group B (p=0.008). However, no significant difference in complication rate was observed between the two groups (p=0.562). Conclusions: Combined subacromial and intravenous patient-controlled analgesia after arthroscopic rotator cuff repair is more effective than solitary intravenous infusion without significantly increasing complications. Therefore, combined subacromial and intravenous patient-controlled analgesia could be a effective pain control method.

• 대한전자공학회논문지SD
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• 제42권9호
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• pp.35-40
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• 2005

본 논문에서는 1.6Gb/s에서 동작하는 digitally controlled phase-locked loop (DCPLL)를 제안한다. DCPLL은 일반적인 아날로그 PLL과 tracking analog-to-digital 변환기를 결합한 구조이다. 제안한 DCPLL에서는 tracking ADC의 출력이 voltage controlled oscillator (VCO)의 제어 전압을 생성한다. 일반적으로 사용되는 digital PLL (DPLL)은 digitally controlled oscillator (DCO)와 time-to-digit converter (TDC)로 구성된다 DCO와 TDC를 사용한 DPLL은 시간 스텝이 작을 수 록 jitter 특성이 향상되지만 전력소모는 커진다. 이 논문에서 제안한 DCPLL은 DPLL의 핵심요소인 DCO와 TDC를 사용하지 않았기 때문에 jitter, 면적, 전력소모 측면에서 유리하다. DCPLL은 $0.18\mu$m 4-metal CMOS공정을 이용하여 제작하였고 면적은 1mm $\times$0.35mm를 차지한다. 1.8V 단일 전원전압으로 정상동작에서는 59mW, power-down 모드에서는 $984\mu$W 전력을 소모하고 16.8ps rms jitter를 갖는다.

• Journal of Periodontal and Implant Science
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• 제34권3호
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• pp.639-646
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• 2004

Dental phobia is the most prevalent fear in all age groups, across gender, and in all countries. One of the primary identified sources is the fear of dental injections in the dental phobia or the high dental fear and anxiety groups. The purpose of this study was to clinically evaluate the computer controlled anesthetic device and to compare it with traditional methods of dental anesthetic delivery. Fifty(mean age : 25.6 yrs) systemically and periodontally healthy volunteers participated in this study. The subjects were given contralateral buccal and palatal injections. One side was injected with the computer-controlled anesthetic device with a microprocessor and an electric motor to precisely regulate flow rate during administration : The experimental group. The control side was injected with a standard manual syringe, in which flow rate and pressure are operator-dependent and can't be controlled accurately : The control group. The subjects described their perceived pain experiences with two subjective scales. The results of this study were as follows: 1. The computer-controlled anesthetic device was significantly less painful than conventional syringe injection 2. The female subjects reported more pain than the male subjects. But, there were no statistical differences. 3. The anesthetic effect of both methods did not show any difference. In this study, it may be concluded that pain levels decreased significantly when the computer-controlled anesthetic device was used.