• 한국농공학회지
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• 제31권1호
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• pp.58-70
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• 1989

The paper compared the Bishop methed to the Fellenius method in the analysis of slope stability. Laboratory model test was carried out in the case of seepage flow considered. The results obtained from this study were summarized as follows; 1. The slice pieces of 10 were enough to analysis the slope stability. 2. The safety factor. by the Fellenius method was lower than the Bishop method by the 96 to 97% in the case of no seepage flow and by the 95 to 96% in the case of seepage flow considered. 3. Besides the parameter of soil and slope, the safety factor of slope was influenced by the height of slope. This phenomena was distinct in the height of height less than 10 meters. 4. In the case of clay, there was no difference in the safety factor of slope between Fellenius and Bishop rnethod. The safety factors of slope with the seepage flow considered were lower than those with no see-page flow. 5. The influence of cohesion on the safety factor was more significant in the Bishop method than in the Fellenius method. 6. The slope failure of model test of A and B soil samples with high permeability coefficient was taken place slightly in vicinity of toe by the concentration of stress and gradually increased 7. Under condition of same slope height, the shapper the slope, the shorter the radius and the center of critical circle appered downward and finally failure of slope occured inside the slope.

• 대한인간공학회지
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• 제35권3호
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• pp.155-163
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• 2016

Objective: This study aims to draw the characteristics of occupational accidents occurred in cabling work, and assess accident severity based on occupational injury data. Background: Accident factors and accident risk are different by the place of work in cabling work. Field managers require information on accident prevention that can be easily understood by workers. However, there has been a lack of studies that focus on cabling work in Korea. Method: This study classifies 450 injured persons caused in cabling work by process, and analyzes the characteristics of occupational injuries from the aspects of age, work experience and accident type. This study also analyzes accident frequency and severity of injury. Results: Results show that preparing/finishing (33.3%) was the most common type of cabling process in injuries, followed by maintenance (28.4%), routing/income (23.1%) and wiring/installation (15.1%) process. The critical incidents in the level of risk management were falls from height in the routing/incoming process, and falls from height in the maintenance process. And, incidents ranked as 'High' level of risk management were slips and trips, fall from height and vehicle incident in the preparing/finishing process, and fall from height in the wiring/installation process. Conclusion and Application: The relative frequency of accident and its severity by working process serve as important information for accident prevention, and are critical for determining priorities in preventive measures.

• 대한치과교정학회지
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• 제7권1호
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• pp.13-22
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• 1977

The author investigated the timing of land and wrist ossification events taking place in the hamate and pisiform by means of roentgenographic examination and its relation to the peak growth velocities in body height. Materials obtained included 493 sheets of X-ray films taken from 257 boys ana 236 girls aged between 7 and 17 years lived in Seoul area. The results indicate that; 1) The average ages at occurrence of initial ossification of the hook of the hamate were 12 years 3 months in boys and 10 years 1 month in girls. 2) The average ages at which advanced ossification of the hook of the hamate occurred were 13 years 7 months in boys and 11 years 11 months in girls. 3) Initial ossification of the pisiform appeared at 13 years 0 month in boys and 10 years 2 months in girls. 4) All three ossification events in hand and wrist, and peak growth velocity in body height occurred earlier in girls than in boys. 5) Initial ossification in the hook of the hamate and pisiform preceded or coincided with peak growth in body height in most boys and girls, on the other hand, advanced ossification in the hook of the hamate occurred around peak growth in body height but in girls did it after peak growth in body height. 6) It would appear that initial ossification in the hook of the hamate or in the pisiform, both for boys and girls, provides a better indication of approaching peak adolescent growth in body height. 7) Advanced ossification in the hook of the tamale would indicate that the period of cercumpuberal peak growth had teen entered or finished.

• Advances in pediatric surgery
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• 제11권2호
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• pp.115-122
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• 2005

Falls from a height are the leading cause of injury and death among urban children. This study describes the incidence, clinical characteristics, and treatment results of children under 15 year of age who fell from a height of more than one meter and were admitted for abdominal injury. The medical records of 585 consecutive patients treated between January 1997 and December 2003 at Ewha Womans University Mokdong Hospital were analyzed retrospectively. The falling heights were 1 to 31.2 meters, and 28 patients(4.8 %) suffered from blunt abdominal trauma. The male to female ratio was 2.1: 1. The median age of the victims was 5.5 years, and the median height fallen was 3 meters. Fifteen patients (53.6 %) were injured during the summer and seventy-nine percent of the falls occurred between noon and 9 pm. Eighteen (64.3 %) of falls occurred in residential place and 19(67.8 %) of patients arrived at the emergency department within 30 minutes of the accident. Only 16 patients (57.1 %) complained of abdominal pain. Liver injuries were found in 12(42.9 %), spleen injuries in 5(17.9 %), kidney injuries 3(10.7 %), pancreatic injuries in 1(3.6 %) and nonspecific abdominal injuries in 9(32.1 %) cases. Increased SGOT and SGPT were found in 23(82.2 %) and 18(64.3 %) cases. Eleven patients (39.3 %) had associated head injuries. Limb injuries were present in 17.9% and thoracic injuries in 7.1%. Twenty-five patients (89.3 %) recovered without operation. The median length of hospital stay was 6 days (2 -20 days). Despite the absence of abdominal symptoms or shock, falls from a height in children may carry significant intra-abdominal organ injuries. The height falling could not predict the degree of the abdominal injury. For the evaluation of potential abdominal injuries, CT scan should be utilized.

• 한국환경생태학회지
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• 제21권5호
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• pp.449-455
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• 2007

상록활엽수림의 복원 사업에 대한 모니터링을 시행하여 상록활엽수림 복원기술개발을 위한 기초자료를 제공하기 위하여 다도해해상국립공원에서 시행한 상록활엽수림 복원 사업을 2005년부터 3년간 모니터링하였다. 5개 시범녹화시험지에서 사면, 섬 크기, 방사가축의 유 무에 따른 생장량과 활착률을 모니터링하였다. 남서사면 능선부에 식재한 상록활엽수의 수고 생장량과 활착률이 북동사면 능선부에 식재한 상록활엽수보다 더 양호하였다. 큰 섬에서 상록활엽수의 활착률이 작은섬보다 높게 나타났다. 방사가축이 있는 곳의 상록활엽수 활착률이 방사가축이 없는 곳보다 매우 낮게 나타났다. 남서사면능선부, 큰섬, 방사가축이 없는 곳에서 상록활엽수림의 생장량과 활착률이 높게 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.361-364
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• 2002

This paper discusses the influencing factors such as coring position, height to diameter ratio of core specimen(h/d) and coring torque on the strength estimation of concrete by small site coring method in order to verify the validities of small size core method. According to results, as for the influence of drilling position, when core specimens are obtained from the place parallel to placing direction, compressive strength of core specimens are higher than those perpendicular to placing direction. This is due to the loss of the area of core specimen perpendicular to plating direction by bleeding. And in case of $\phi$ 24mm core specimen, when vertical drilling against placing direction is taken. compressive strength of core specimen obtained at the bottom of the structure is higher than that at the top of the structure. As for the influence of height to depth ratio, as h/d ratio increases compressive strength shows to be decreased. As for the influences of rotation speed of drilling machine, as its speed goes up, compressive strength decreases, regardless of core diameter.

• 한국항해항만학회지
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• 제35권7호
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• pp.557-562
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• 2011

Shipwaves can have harmful effects on people who are using riverside and cause bank erosion, bank structures destruction in restricted waterways. The wave field near a vessel is consisted of a combination of a primary and secondary wave system in a shallow or restricted waterway. The water level depression(squat) and return current beside the hull are called the primary wave system. The secondary wave system, that is the wave height originates from a local disturbance point such as the bow of the ship. This study aims at investigating the characteristics of the wave field around a vessel in a restricted water in relation to navigation experimentally and theoretically. The return current and squat with a correction factor can be newly evaluated and the almost same high-sized wave heights take place on the whole waterway in a restricted water without regard to the distance from the sailing line.

• 한국진공학회지
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• 제8권4A호
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• pp.476-481
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• 1999

Characteristics of platinum dry etching were investigated in a cryogenic magnetized inductively coupled plasma (MICP). The problem with platinum etching is the redeposition of sputtered platinum on the sidewall. Because of the redeposits on the sidewall, the etching of patterned platinum structure produces feature sizes that exceed the original dimension of the PR size and the etch profile has needle-like shape [1]. The main object of this study was to investigate a new process technology for fence-free Pt etching As bias voltage increased, the height of fence was reduced. In cryogenic etching, the height of fence was reduced to 20% at-$190^{\circ}C$ compared with that of room temperature, however the etch profile was not still fence-free. In Ar/$SF_6$ Plasma, fence-free Pt etching was possible. As the ratio of $SF_6$ gas flow is more than 14% of total gas flow, the etch profile had no fence. Chemical reaction seemed to take place in the etch process.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.311-314
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• 2005

Bond between reinforcing bar and surrounding concrete is supposed to transfer load safely in the process of design of reinforced concrete structures. Bond failure of reinforcing bar generally take place by splitting of the concrete cover as bond force between concrete and reinforcing bars exceeds the confinement of the concrete cover and reinforcement. In this study, to evaluate bond strength of high relative rib area bars, beam-end bond and splice beam specimens are tested and the results are discussed. Higher rib height bars when bars are confined showed higher bond strength than lower rib height bars.

• 대한임베디드공학회논문지
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• 제6권5호
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• pp.273-280
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• 2011

In this paper, we describe the structural reinforcement approach of the throwing-type firefighter assistance robot which can be thrown into a fire site to monitor inside the place and search trapped people while ensuring a firefighter's safety. The reinforcement design is focused on high strength with low weight for the robot. The in-depth structural analysis of the platform is carried out to track down the weakest part, especially with the 1.8m height of drop test. The analysis is verified by comparing with the 1.8m height of the drop test of the throwing-type firefighter assistance robot. The optimal approach for improving the strength of the weakest part aims at topological equivalent and equivalently stress distributed shape.