• Journal of Nutrition and Health
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• v.40 no.6
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• pp.576-583
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• 2007

The purpose of this study was to assess the daily steps, physical activities and activity coefficient of policemen (average age: 31.5 ${\pm}$ 5.1 years) who do shift work. Body weight, height and daily steps were measured and one-day activity diary was collected by interviewing with policemen. Average height, body weight, BMI, body fat (%) and muscles (%) of subjects were 173.1 ${\pm}$ 5.2 cm, 73.7 ${\pm}$ 9.7 kg, 24,6 $kg/m^{2}$, 15.5 ${\pm}$ 1.9% and 37.3 ${\pm}$ 5.8%, respectively. The average daily numbers of steps were found to be 9,812 steps/day on day shift duty and 10,888 steps/day on night shift duty and 6,551 steps/day on holiday duty. Hourly step rates on day shift, night shift and holiday came to 1946 steps/hr, 2,130 steps/hr and 1,318 steps/hr, respectively. Activity coefficient (1.75) in night shift of the subjects was the highest and activity coefficient (1.52) in day shift was significantly higher than that (1.31) in holiday (p < 0.05). The rate of expending time for very light activity in holiday (91.5%) was significantly higher than that (70.0%) in night shift. The muscle mass (kg, %) had significantly positive relationship with daily steps in day shift (r = 0.592, r = 0.632) and night shift (r = 0.550, r = 0.503). Triceps skinfold thickness was negatively correlated with daily steps in day shift (r = -0.366, p < 0.05). There were remarkable differences in physical activities and sleeping hours depending on shift works of policemen. In the case of night shift work, sleeping hours was the lowest and activity coefficient was the highest among day shift, night shift and holiday. These results suggest that energy requirements of policemen should be differentiated according to shift work duty.

• Journal of the Korea Institute of Building Construction
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• v.15 no.6
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• pp.653-660
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• 2015

Technologies for reducing construction duration are key factors in nuclear power plant construction projects, as a reduction in construction duration at the construction phase leads to a reduction in construction cost and an increase in profits through the early operation of the nuclear power plant. To analyze the constructability of the height of single-layer placement of formwork for the Reactor Containment Building (RCB) exterior wall through lateral pressure according to the height of concrete placement, the deformation criteria for formwork, and a new form design, 'MIDAS GEN (hereinafter referred to as MIDAS)' is used in this study. The cost and workload of formwork are derived according to the unit of height of the RCB exterior wall. Based on the result, it was found that the higher the RCB exterior wall, the higher the material cost, and the less the construction duration and the less the total number of formwork layers. Based on this result, it is believed that the material cost and the construction duration can be appropriately determined according to the formwork height.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.114-117
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• 2009

In this work, closing behavior of the voids generated in a casting process was investigated for various parameters such as reductions in height void size and billet rotation during hot open die forging process. The reduction in height and path schedule including the number of paths and billet rotation were chosen as key process variables to express the change of geometrical void shape and void closing behavior. On the other hand, values of die overlapping and die width ratio were set to be constant. Extend of void closure was observed and evaluated using tensile test and microscope. Based on the experimental result, it is ensured that void closure do not occur at 15% and 30% reduction in height as well as one or two rotations of a billet. The useful datum obtained from this study could be utilized to establish an optimum path schedule in the open die forging process.

• Journal of Families and Better Life
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• v.4 no.1
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• pp.49-69
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• 1986

This study aimed to fine out the rational quantity of kitchen utensils and appliances Questionnair was distributed to families of 469 of middle school students. I studied status of kitchen work centers, quantity and the kinds of kitchen utensils. The results were as follows. 1. the status of kitchen :1) The percentage of western style work centers was significantly higher than the average level of Seoul. 2) The length and the height of work centers were below standard. 3) Arrangement of work centers was relatively correct, however, the kinds of kitchen work centers were not fully equipped. 2. The quantity of kitchen utensils: The socio-economic status were the main factor of the quantity of kitchen utensils. Educational level, income level and floor space were strongly corrected to the quantity of kitchen utensils.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.229-233
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• 2011

Recently, the scale of buildings has been increasing because of the high-rise trend and complexity of underground spaces. A significant number of steel structures have therefore been adopted for building construction. Since workers need to work in high places to install steel beams, many industrial accidents easily occur during steel-frame work. Furthermore, considering the increasing trend of building steel structures, the safety of the workers during the steel beam erection work is of concern. To improve the safety, a new type of joint, located between the steel column and beam, which can eliminate the need for working at the elevated height during steel beam erection has been developed in Korea. Using the newly developed technology in the construction field, the safety performance needs to be evaluated. This study presented the safety evaluation approach for the newly developed technology from the literature review, and applied the method to a self-supported steel joint. The result showed that applying the self-supported steel joint improved the safety of the steel erection work in terms of working posture, working environment, and risk exposure time.

• Korean Journal of Applied Biomechanics
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• v.22 no.3
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• pp.315-324
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• 2012

The purpose of current study was to investigate the effects of the heights on the lower extremities, torso and neck segments for energy dissipation during single-leg drop landing from different heights. Twenty eight young healthy male subjects(age: $23.21{\pm}1.66yr$, height: $176.03{\pm}4.22cm$, weight: $68.93{\pm}5.36kg$) were participated in this study. The subjects performed the single-leg drop landing from the various height(30, 45 & 60 cm). Force plates and motion-capture system were used to capture ground reaction force and kinematics data, respectively. The results were as follows. First, the ROM at the ankle, knee, hip and trunk was increased with the increased heights but the ROM at the neck was increased in the 60cm. Second, the angular velocity, moment and eccentric work at the ankle, knee, hip, trunk, and neck was increased with the increased heights. Third, the contribution to total work at the knee joint was not significantly different, while the ankle joint rate was decreased and hip and neck rate was increased in the 60cm, and trunk rate was increased with the increased heights. Lastly, the increase in landing height was able to augment the level of energy dissipation not only at the lower extremities but also at the trunk and neck. The findings showed that drop landing affect trunk and neck with lower extremity joints. Therefore, we need to consider that trunk and neck strengthening including stability should be added to reduce sports injury during prevention training.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.1
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• pp.36-49
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• 1998

The purpose of this study is to investigate the relationship between the work postures and upper extremity cumulative trauma disorders(CTDs) in female medical insurance bill reviewers(n=448). This study included diagnosis for CTDs, anthropometry and job analysis (workstations and posture). The characteristics of subject were 33.6 years of average age and 8.7 years of average work duration. The results were as fallows. Ergonomic conditions of workstation were unsuitable compared with anthropometry result. The height of work surface(79.5 cm) and chair(43.0 cm)were high. work space was small, and legs space under the table was limited. Work postures were awkward compared with recommended neutral postures. Neck flexion($21.0-36.0^{\circ}$), elbow elevation, shoulder abduction ($46.0-47.0^{\circ}$). wrist radial and ulnar deviation, forearm supination and pronation, and wrist repeated motion(12.7-21.5 freq./min) were analyzed as hazardous risk factors by job analysis. The prevalence of CTDs was 32.8 % by medical diagnosis. The prevalence rate of CTDs in hazardous work posture group was significantly greater than safe work posture group both neck-shoulder (relative prevalence = 5.2, p<0.001) and wrist-hand (relative prevalence = 2.5, p<0.05).

• Proceedings of the Korean Geotechical Society Conference
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• 2001.10a
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• pp.329-336
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• 2001

The numbers of geogrid-reinforced walls are widely used in Korea. This papers present the results of two failure case histories of geogrid-reinforced segmental retaining walls. The geological background of the construction sites, detailed construction sequences, and the amount of rainfall were examined. The failure of these reinforced walls are caused by the improper drainage system and foundation treatment, too sharpened curvature of corner work, and too high height of wall.

• Industrial Engineering and Management Systems
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• v.6 no.2
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• pp.146-157
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• 2007

This paper discusses two algorithms for recommending notebook computer (NBC) and workstation adjustments so that the user can assume an ergonomic seated posture during NBC operation. Required input data are the user's anthropometric data and physical dimensions of the NBC and the workstation. The first algorithm is based on an assumption that there are no workstation constraints while the second algorithm considers the actual seat height and work surface height. The results from the algorithms include recommendations for adjusting the NBC (tilt angle of the NBC base unit, angle between the base and screen units, and base support height) and the workstation (heights of seat support and footrest, and distance between the body and the NBC).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.517-520
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• 2003

The snow-fatting measurement system including the snow sensor applying the photo-coupler is investigated in this study and using this snow sensor the height of snow fallen is measured. To measure the snow depth, five photo sensors are arranged with 5 mm distance. The snow-falling measurement system, which is measuring the motor revolution controlled with stepping motor, is mounted above the snow surface. From this work, it is feasible to measure quantitatively the snow on real time. Its software implements a proven method to achieve valid measurements also under difficult conditions as future study. In cases where the snow sensor is applieded to the prediction of snow in the meteorological observation system and the snow removing system, it is recommend the GRS-Option in order to improve the quality of snow measurements for better compensation.