• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.91-91
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• 2017

Drought is the most serious abiotic stress limiting rice production. However, little progress has been made in the genetic analysis of drought tolerance, because it is a complex trait controlled by a number of genes and affected by various environmental factors. In here, we screened 218 rice genetic resources for drought tolerance at vegetative stage and selected 32 highly drought tolerant varieties in greenhouse. Under rain-fed conditions, Grain yield of Nagdong was decreased by 53.3% from 517 kg/10a to 241 kg/10a when compare to irrigation condition. By comparison, grain yield of Samgang was decreased by 23.6% from 550 kg/10a to 420 kg/10a. The variety Samgang exhibited strong drought tolerance and stable yield in rain-fed conditions and was selected for further study. To identify QTLs for drought tolerance, we examined visual drought tolerance (VDT) and relative water content (RWC) using a doubled haploid (DH) population consisted of 101 lines derived from a cross between Samgang (a drought tolerance variety) and Nagdong (a drought sensitive variety). Three QTLs for VDT were located on chromosomes 2, 6, and 11, respectively, and explained 41.8% of the total phenotypic variance. qVDT2, flanked by markers RM324 and S2016, explained 8.8% of the phenotypic variance with LOD score of 3.3 and an additive effect of -0.6. qVDT6 was flanked by S6022 and S6023 and explained 12.7% of the phenotypic variance with LOD score of 5.0 and an additive effect of -0.7. qVDT11, flanked by markers RM26765 and RM287, explained 19.9% of the phenotypic variance with LOD score of 7.1 and an additive effect of -1.0. qRWC11 was the only QTL for RWC to be identified; it was in the same locus as qVDT11. qRWC11 explained 19.6% of the phenotypic variance, with a LOD score of 4.0 and an additive effect of 9.7. To determine QTL effects on drought tolerance in rain-fed paddy conditions, seven DH lines were selected according to the number of QTLs they contained. Of the drought tolerance associated QTLs, qVDT2 and qVDT6 did not affect tiller formation, but qVDT11increased tiller number. Tiller formation was most stable when qVDT2 and qVDT11 were combined. DH lines with both of these drought tolerance associated QTLs exhibited the most stable tiller formation. These results suggest that qVDT11 is important for drought tolerance and stable tiller formation under drought stress condition in field.

• Proceedings of the ESK Conference
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• 1998.04a
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• pp.161-166
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• 1998

In this study, the optimum criteria of space between the lines and the letters which could largely affect the legibility were found by the experiment and were presented as guidelines to design Korean VDT screens. Since the experiment was designed to test the human performance based on the VDT screen design, searching speed (S.S) and error rate (E) were used as the criteria of performance, and CFF value was measured to evaluate user's visual fatigue. The EOG value was also measured for the visual restriction during the experiment for the space between the lines and letters.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.281-282
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• 2000

한국은 세계에서 열번째로 많은 1000만명 이상이 인터넷을 이용하고 있다. 학생부터 직장인까지 문서작업과 업무가 컴퓨터로 이루어지면서, 컴퓨터의 사용으로 인한 질병도 확산되고 있다. 모니터에서 발생되는 전자파에 장시간 노출로 인한 각종 전자파 유해가 생기고 여러가지 신경계통에 대한 장해가 증가하고 있다. 이른바 컴퓨터를 통해 정보를 입출력하는 과정에서 생기는 증후군이 VDT(Visual Display Terminal)증후군이다. (중략)

• Proceedings of the ESK Conference
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• 1997.04a
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• pp.265-269
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• 1997

A series of experiments was carried out while using totally six female subjects in order to evaluate their psycho-physilolgical variations during their work with VDT both subjectively and objectively compared to those of ordinary office type work and speech communication type work. The results led by the experiment were as follows; the effects with data input work on the subjects from the view point of psychological load was larger than those with the ordinary office work. Oral communication between subjects gave the positive effects upon each subjects to reduce their psychological and mental burden.

• Proceedings of the ESK Conference
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• 1998.04a
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• pp.194-199
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• 1998

The purpose of this study is conducted to evaluate the psycho-physiological effects of the dynamic lighting on VDT workers and to establish the dynamic lighting design guides. The main experimental factors are changes of illuminance. There were five conditions including 1) ripid change, 2) slow change at 300lx .approx. 500lx, 3) a static illuminance level at 300lx, and 4) rapid chante, 5) slow change at 200lx .approx. 300lx. The ranges of change were set typical illuminance level for the simple visual task requirement and reasonable to a VDT task ; 200-300-500lx. The psycho-physiological measurements used were EEG, R-R interval, CFF, near point accommodation, feeling perceived fatigue, and work performance. Analysis of psycho-physiological factors shows that higher illumination level conditions are more affirmative effects than lower on VDT workers under 500lx except for the results of feeling perceived fatigue. And about the speed of changes of illuminance level. The conditions of slow change were better than the others in terms of the work performance as well as psycho-physiological results.

• Journal of the Korea Safety Management & Science
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• v.11 no.4
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• pp.77-83
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• 2009

The purpose of this study was to examine the relative effectiveness of immediate feedback and informational prompt on safe sitting behaviors that may cause VDT syndromes. Participants were three white color workers and an ABCB within-subject design was adopted. Safety Posture System was developed specifically for the present study. The system could detect participants' unsafe sitting postures using sensors and provide feedback and prompt on the computer monitors. The results indicated that both immediate feedback and informational prompt considerably increased safe sitting behaviors. More importantly, the immediate feedback was more effective than the informational prompt in increasing safe sitting behaviors.

• Proceedings of the ESK Conference
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• 1995.10a
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• pp.109-113
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• 1995

This study was designed to investigate the effects of work postures and anthropometry on the musculoskeletal discomfort of the telephone operators involved in VDT tasks. The level of musculoskeletal discomfort were evaluated for 279 VDT operators from three different workplaces. The work postures and the anthropometric data were evaluated for 70 VDT operators out of the total of 279 operators. Multiple regression analysis was utilized to examine the relation- ship between the measured ergonomic variables and the level of the musculoskeletal discomfort. It is evident from the result of the study that the ergonomic factors have great influences on the level of the musculoskeletal discomfort.

• The Journal of Korean Physical Therapy
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• v.17 no.2
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• pp.1-10
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• 2005

This study is going to have been recognized a change of Cervical range of motion with the object 40 persons who sat for many hours before computer. According to the therapy term, sling used joint mobility exercise and Mckenzie was executed by 20 persons Shared. The study results about the effect that Cervical exercise had on joint Range of motion of a VDT syndrome patient were as follows. 1. There was a similar difference a sling used in Cervical Range of motion of joint mobility exercise cure after one-week, two-weet and three-week. 2. The change Cervical Range of motion of Mckenzie exercise has not been after one-week and two-week but a similar difference happens after three-week. 3. There has not been difference between joint mobility exercise and Mckenzie exercise in cure ferm sling used.

• Proceedings of the ESK Conference
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• 1997.04a
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• pp.150-155
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• 1997

VDT의 한글 화면을 탐색하는데 있어 가독성에 영향을 주는 요인에 대한 연구는 한글 VDT 화면의 표준지침 선정의 기초자료로서 중요하게 활용될 수 있으나 그 연구가 부족한 실정이다. 영어와 한글의 글자체계에는 차이가 있어 외국의 연구결과 및 표준지침을 적용하는 것은 무리가 있기 때문에 한글 글 자체계에 대한 쳬계적이고 인간공학적 연구가 시급하다 할 수 있다. 이에 본 연구에서는 글자크기와 서체(font)를 선정하여 사용자의 시각성능과 관련하여 최적의 수행도 및 피로도를 경감하여 주는 서체와 글자크기 수준을 실험을 통하여 제시하였다. 그 결과는 다음과 같다. (1) VDT 화면에서 한글 고딕체가 명조체보다 사용자의 시각성능 및 수행도가 우수하다. (2) 초적의 수행도를 주는 글자크기는 명조체의 경우 35.4' .approx. 55.5', 고딕체의 경우 시각 39.8 .approx. 52.6'이다. (3) 우수한 수행도를 보이는 글자크기에서 피로도 저하율이 낮게 나타난다.

• Journal of Haehwa Medicine
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• v.13 no.1
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• pp.295-302
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• 2004

Nowadays VDT(Visual Display Termimal) syndrome-especially causes disorder of skeletalmuscular structure, ophthalmic organ, neuropsychiatic parts, etc.-are so common and many people are suffering from it. The purpose of this study is to investigate the clinical result of patients diagnosed as shoulder-arm syndrome by VDT work. This study carried out on 50 patients who have been treated at Cheonan Oriental hospital(Daejon University), February 2nd, 2003 to May 31th, 2004. The patients were classified into age, sex, the period between onset and visit, symptom, clinical diagnosis and so on. And the methods of treatment were acupuncture, herbal medication, oriental physical therapy, Chuna, etc. About treatment results, Exellant were 12(24.00%), Improve were 25(50.00%), Mild improve were 11(22.00%), Failure were 2(4.00%)