• Safety and Health at Work
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• v.13 no.4
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• pp.440-447
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• 2022

Background: Agricultural handle equipment is present on all production areas' farms. They are handy and portable; however, excessive use can lead to acute traumas or accidental injuries. Repetitive movements, awkward postures, and hand-arm vibrations predispose them to pain and work-related musculoskeletal disorders. The purpose of this study was to observe the interaction of handle equipment in terms of electromyographic activity and analyze the postural work-related alterations. Materials and methods: Twenty male agricultural operators, mean age 24±1.54 years, underwent the electromyographic analysis testing their muscular activities with a brushcutter, electric saw, and hedge trimmer in four different test conditions. Results: The brushcutter proved to be the agricultural handle equipment with the higher mean frequency (3.37±0.38 Hz) and root mean square (5.25±1.24 ms^-2). Furthermore, the digital postural analysis showed a general asymmetry of the main arm and the respective side of the trunk. The head resulted right inclined in the anterior frontal plane by 5.7°±1.2°; the right scapula lower than the left in the posterior frontal plane (8.5°±1.8°), and a working trunk inclination of 34.15°±5.7°. Conclusions: Vibrations of handle equipment and awkward working postures represent a risk for agricultural operators. Preventive measures are required to avoid young operators from experiencing musculoskeletal disorders all lifelong.

• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.9-28
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• 2000

The purpose of this article, the first part of series, is to describe the general theory applicable to various chromatographic procedures. History of chromatography, separation of matters, classification of chromatography, underlying principles of separation in chromatography, covering resolution, column efficiency, column selectivity, and capacity factor, movement of solute in chromatographic phase, including elution development, displacement development, and frontal analysis, were discussed. Mathematical description of plate theory and thermodynamic viewpoint of retention were emphasized.

• Transactions of the Korean Society of Mechanical Engineers
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• v.3 no.2
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• pp.48-59
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• 1979

인간의 근육에 걸리는 힘에 대한 연구는 치료나 생체공학분야에서 대단히 중요한 부분을 차지하고 있다. 본 연구에서는 팔을 전두면(Frontal plane) 상에서 0.deg. 부터 90.deg. 까지 외전(Abduction)시킬 때 어깨근육에 작용되는 힘을 결정하는 방법을 개발시켰다. 여기에서는 해부한, 생리학적인 데타와 벡타해석 및 수학의 방법을 사용하였으며 정력학적으로 부정정(Inderterminant)인 문제를 ㅂ풀기 위하여 Minimal Effort Principle이 사용되었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.651-654
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• 1997

Generally commercial FEA program needs computer circumstances such as specific operating system, hardware. But regardlessly to computer circumstances, program coded by JAVA can work only with webbrowser. 2 dimensional mesh generation and FE analysis using JAVA is presented in this paper.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2003.08a
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• pp.98-102
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• 2003

지금까지 실무에서는 경사식 방파제 적정 단면 결정시 피복재 산정 및 설계파에 대한 파력을 산정하여 상치콘크리트 구조물의 안정성을 검토하는 것이 전부였다 하지만 현장에서 발생하는 상황은 더 많은 변수들이 작용하는 것을 보여 주고 있다. 예를 들면 파에 의하여 발생하는 투과파 및 월파로 제체의 내부 및 배면 석재의 이탈이 발생하는 경우는 익히 보아 왔던 일이지만, 반대로 월파가 발생하지 않았는데도 불구하고 제체의 침하와 배면의 석재에 이탈 즉 세굴이 발생하는 경우도 있다. (중략)

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.11b
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• pp.107-116
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• 2005

Precipitated silicas modified by aluminium were characterised using inverse liquid chromatography in anhydrous heptane with squalene as probes. Their monolayer capacities of adsorption, Langmuir's and Henry's constants were determined from the desorption isotherms according to frontal analysis. A narrow band consisting of isotherms was observed. The introduction of aluminium has little influence on the monolayer capacity, Langmuir's constants and the Henry constant. Experimental data show that neither the amounts of aluminium on the silica nor the methods of the introduction of aluminium into the silica influence the interactions between the squalene and the silicas.

• Journal of Korean Society of Transportation
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• v.12 no.1
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• pp.97-116
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• 1994

Today advanced traffic management systems are required because of a high increase in traffic demand. Accordingly, the objective of this study is to take advantage of image processing systems and present image processing methods available for collection of the data on traffic characteristics, and then to investigate the possibility of traffic flow analysis by means of comparison and analysis of measured traffic flow. Data were collected at two places of Daegu city and Kyongbu expressway by using VTR. Rear view (down stream) and frontal view (up stream) methods were employed to compare and analyze traffic characteristics including traffic volume, speed, time-headway, time-occupancy, and vehicle-length, by analysis of measured traffic flow and image processing respectively. Judging from the results obtained by this study, image processing techniques are sufficient for the analysis of traffic volume, but a frame grabber equipped with high speed processor is necessary as well, with low level system judged to be sufficient for traffic volume analysis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.6
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• pp.490-496
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• 2011

Purpose: Dr. Marquardt made the facial 'phi' mask using golden ratio. Most class III patients have bulky faces and want a smaller face. Using a facial golden mask, this study estimated and compared frontal photographs before and after operation for soft tissue measurement. The golden mask can be considered as a reference tool for facial esthetic analyses especially in lower face. Methods: Forty patients who had undergone orthognathic surgery at Samsung Medical Center from January 2006 to December 2009 were included in this study. These patients had Class III malocclusion. Lateral cephalometric radiographs, frontal clinical photos of pre-op and 8~12 month later post-op, and the facial 'phi' mask using golden ratio, were used for analysis. Reduction of the lower face area, occlusal plane changes, amounts of mandible setback and amounts of maxilla posterior impaction were estimated. Results: Lower facial reduction ratio and mandibular setback amounts were significantly different between 1-jaw and 2-jaw groups. Average postoperative changes in the area of lower face between bilateral sagittal split ramus osteotomy (BSSRO) and BSSRO combined maxilla posterior impaction were compared by using an independent simple t-test and $P$ value was 0.016. Therefore, the lower facial reduction ratio and mandibular setback amount were significantly different in maxilla posterior impaction. Conclusion: The two-jaw surgery group showed more reduction of the lower facial area than the 1-jaw surgery group. The amount of lower facial reduction was more related with the amount of mandibular setback. There was no significant relation in lower facial reduction with amount of maxilla posterior impaction, pre-op occlusal plane, post-op occlusal plane and the mandibular angle. A relationship between the change in the lower facial area and the amount of maxilla posterior impaction or the change of mandibular angle occlusal plane at pre-op could not be found because of the difference in the amount of setback between two groups.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.2
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• pp.23-30
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• 1997

Modelling and crashworthiness analysis of simplified vehicle structures with beam element and nonlinear spring element to which axial and bending collapse mecha- nisms are applied are carried out. And on the basis of these analyses, two types of full car modelling and crahworthiness analyses with nonlinear spring and beam element are accomplished. The one is the full car model of which 30% of the structures are modelled with nonlinear spring and beam element, and the other 75% of whole structures. And the results are compared with those of full car analysis with shell element.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.135-142
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• 2004

The severe frontal crash tests are NCAP with belted occupant at 35mph and FMVSS 208 with unbelted occupant at 25mph, This paper describes the design process of occupant protection systems, airbag and seat belt, under the two tests. In this study, NCAP simulations are performed by Monte Carlo search method and cluster analysis. The Monte Carlo search method is a global optimization technique and requires execution of a series of deterministic analyses, The procedure is as follows. 1) Define the region of interest 2) Perform Monte Carlo simulation with uniform distribution 3) Transform output to obtain points grouped around the local minima 4) Perform cluster analysis to obtain groups that are close to each other 5) Define the several feasible design ranges. The several feasible designs are acquired and checked under FMVSS 208 simulation with unbelted occupant at 25mph.