• 생물환경조절학회지
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• 제16권3호
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• pp.258-263
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• 2007

'후지'/M.9에 대한 세장방추형에 적합한 하단측지수 구성을 위하여 하단측지수를 달리하여 수체생육, 광환경, 수량 및 과실품질을 조사하였다. 하단측지수준별 생육은 하단측지수를 5개로 유지했을 때 수폭은 넓었고, 신초장 및 정단신초장은 증가하였다. 수관위치별 수광률은 하단측지수가 5개인 처리구에서 수관상부(지상 150cm)와 수관중부(지상 100cm)에서는 높은 경향을 보였다. 총 단과지 화아수는 측지수에 따라 차이가 없었으나, 수관위치별로 보면 수관하부(지상 120cm 이하)에서 하단측지수가 5개 처리에서 가장 많았으며, 화아의 횡경도 커지는 경향이었다. 과실수량은 하단측지수가 5개에서 가장 많았고, 과중은 하단측지수가 5개와 8개에서 증가하는 경향이었다. 과실특성은 과형지수, 경도, 산함량, Hunter L, b값은 수관위치와 측지수준에 따라 차이가 없었으나, 가용성고형물 함량은 하단측지수가 5개일 때 높았다. 과실의 착색도를 나타내는 Hunter a값은 수광률이 가장 높은 하단측지수를 5개로 유지한 처리구에서 가장 높게 나타났다.

• 대한인간공학회지
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• 제30권5호
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• pp.671-681
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• 2011

Objective: The purpose of this study is to compare the workload level at each lower limbs posture and suggest the ergonomic workstation guideline for working period by evaluating the imbalanced lower limbs postures from the physiological and psychophysical points of view. Background: Many workers like welders are working in various imbalanced lower limbs postures either due to the narrow working conditions or other environmental conditions. Method: Ten male subjects participated in this experiment. Subjects were asked to maintain 3 different lower limbs postures(standing, squatting and bending) with 3 different working conditions(balanced floor with no scaffold, imbalanced floor with 10cm height of scaffold, and imbalanced floor with 20cm height of scaffold). EMG data for the 4 muscle groups(Retus Femoris, Vastus Lateralis, Tibialis Anterior, Gastrocnemius) from each lower limbs posture were collected for 20 seconds every 2 minutes during the 8 minutes sustaining task. Subjects were also asked to report their discomfort ratings of body parts such as waist, upper legs, lower legs, and ankle. Results: The ANOVA results showed that the EMG root mean square(RMS) values and the discomfort ratings(CR-10 Rating Scale) were significantly affected by lower limbs postures and working time(p<0.05). The correlation was analyzed between the EMG data and the discomfort ratings. Also, prediction models for the discomfort rating for each posture were developed using physical condition, working time, and scaffold height. Conclusion: We strongly recommend that one should not work more than 6 minutes in a standing or squatting postures and should not work more than 4 minutes in a bending posture. Application: The results of this study could be used to design and assess working environments and methods. Furthermore, these results could be used to suggest ergonomic guidelines for the lower limbs postures such as squatting and bending in the working fields in order to prevent fatigue and pain in the lower limbs body.