• Archives of Plastic Surgery
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• v.36 no.6
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• pp.773-778
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• 2009

Purpose: The authors propose the new classification of fatty - type gynecomastia(lipomastia) which can serve as a guide for modifying the periareolar technique. Methods: A retrospective analysis was made of 1000 cases of lipomastia operated on in the last 17 months. The extent of the clinical result, the technique employed, and the complications were observed. On the basis of this review the authors observed that at grade I(fat component < 50 ml, fibroglandular component < 3 g each breast), flattening of the thorax can be achieved by means of stab incision, ultrasound - assisted lipectomy(UAL), scavenging suction - assisted lipectomy(SAL) and tissue shaving. At grade II(50 < < 150 ml, 3 < < 5 g), stab incision, UAL, SAL and pull - out method(POM) using small curved scissors. At grade III(150 < < 300 ml, 5 < < 15 g and prominent inframammary fold(IMF)), minimal incision (5 - 6 mm), UAL, SAL and POM using small angulated scissors, and blunting IMF. At grade IV (300 < < 500 ml, 15 < < 30 g, and glandular ptosis), minimal incision (5 - 6 mm), UAL, SAL, fibroglandular excision using small angulated scissors, cutting IMF and fixation of nipple - areola complex(NAC) becomes necessary. At grade V (> 500 ml, > 30 g and ptosis), small incision (7 - 8 mm), UAL, SAL, fibroglandular excision using large angulated scissors, cutting IMF, upper repositioning of NAC and delayed circumareolar skin reduction or chest lifting becomes necessary. Results: The complications were minimal but there were hematoma (n = 7), infection (n = 3) and hypertrophic scar (n =13). Almost patients were satisfied with the outcome. Conclusion: This simple classification may help in choosing the most suitable treatment, thus avoiding insufficient or invasive treatments and undesirable scars.

• Journal of the Semiconductor & Display Technology
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• v.7 no.4
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• pp.29-33
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• 2008

Rapid increase of integrity for recent semiconductor industry highly demands the development of removal technology of contaminated particles in the scale of a few microns or even smaller. It is known that the surface cleaning technology using $CO_2$ snow has its own merits of high efficiency. However, the detailed removal mechanism of particles using this technology is not yet fully understood due to the lack of sophisticated research endeavors. The detachment mechanism of particles from the substrates is known to be belonged in four types; rebounding, sliding, rolling and lifting. In this study, a modeling effort is performed to explain the detachment mechanism of a contaminant particle due to the rebounding caused by the vertical collision of the $CO_2$ snow. The Hertz and Johnson-Kendall-Roberts(JKR) theories are employed to describe the contact, adhesion and deformation mechanisms of the particles on a substrate. Numerical simulations are followed for several representative cases, which provide the perspective views on the dynamic characteristics of the particles as functions of the material properties and the initial inter-particle collision velocity.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.2
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• pp.147-157
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• 2011

A RANS(Reynolds averaged Navier-Stokes) based numerical method is developed for the evaluation of ship resistance and self-propulsion performances. In the usability aspect of CFD for the hull form design, the field grid around practical hull forms is generated by solving a grid Poisson equation based on the hull surface grid generated from station offsets and centerline profile. A body force technique is introduced to model the effects of the propeller in which the propeller loads are obtained from potential flow analysis using an unsteady lifting surface method. The free surface is captured by using a two-phase level-set method and the realizable $k-{\varepsilon}$ model is used for turbulence closure. The hull attitude in vertical plane, i.e., trim and sinkage, is calculated by using a quasi-steady method and then considered in the computation by translating and rotating the grid system according to the values. For the validation of the proposed method, the numerical results of resistance tests for KCS, KLNG, and KVLCC1 and of self-propulsion test for KCS are compared with experimental data.

• Journal of the Ergonomics Society of Korea
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• v.27 no.1
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• pp.45-51
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• 2008

The purpose of this survey was to identify ergonomic risk factors of work-related musculoskeletal disorders (MSD) and understand the current MSD risk status in the wholesale/retail industry. The field survey was conducted at 120 wholesale/retail establishments, and the cause of MSD occurred from the national industrial accident statistics by the Ministry of Labor in 2006 was analyzed in terms of company size, a term of work, job title, and cause of occurrence. The numbers of disasters on MSD were 602 which were included 432 disasters who met with low back pain by incident. A checklist was developed by KOSHA to use for the field survey. A total of 419 tasks were identified at the 120 establishments surveyed. The highest frequency was Task 2(45%) which was mostly observed in repetitive work (e.g. displaying, scanning, cutting or wrapping of goods). The second and third were Task 9(34%) and Task 8(14%) which were identified in manual materials handling (e.g. lifting, lowering, carrying or stocking of goods). The results suggest that the three Tasks should be first considered for the control in wholesale/retail industry and that exposure to MSD risk factors in those Tasks should be primarily addressed in order to reduce MSD risk in that industry.

• Bulletin of the Society of Naval Architects of Korea
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• v.27 no.4
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• pp.15-26
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• 1990

This paper describes a potential-baoed panel method formulated for the analysis cf a supercavitating two-dimensional symmetri strut. The method employs normal dipoles and sources distributed on the foil and cavity surfaces to represent the potential flow around the cavitating hydrofoil. The kinematic boundary condition on the wetted portion of the foil surface is satisfied by requiring that the total potential vanish in the fictitious inner flow region of the foil, and the dynamic boundary condition on the cavity surface is satisfied by requiring that the potential vary linearly, i.e., the tangential velocity be constant. Green's theorem then results in a potential-based integral equation rather than the usual velocity-based formulation of Hess & Smith type, With the singularities distributed on the exact hydrofoil surface, the pressure distributions are predicted with improved accuracy compared to those of the linearized lifting surface theory, especially near the leading edge. The theory then predicts the cavity shape and cavitation number for an assumed cavity length. To improve the accuracy, the sources and dipoles on the cavity surface are moved to the newly computed cavity surface, where the boundary conditions are satisfied again. This iteration process is repeated until the results are converged.

• Physical Therapy Korea
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• v.24 no.2
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• pp.76-91
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• 2017

Background: Agricultural work is physically demanding and is associated with a high frequency of musculoskeletal disorders. It is challenging to comprehensively understand the present status of work-related diseases and injuries among farmers in underdeveloped countries. Objects: This study aimed to elucidate the current status of work-related musculoskeletal disorders in local farmers in Tigray, Ethiopia, and identify the agricultural factors associated work-related musculoskeletal pain (AFWMP) and healthy living and healthy behavior factors associated work-related musculoskeletal pain (HFWMP). Methods: The Institute for Poverty Alleviation and International Development at Yonsei University conducted a survey of 126 households in Tigray, Ethiopia in 2014. A total of 116 individuals (73 men, 43 women) representing each household answered the questionnaires. Results: 1) Work-related musculoskeletal pain (WMSP) most commonly occurred when performing heavy lifting and most frequently occurred in the lower back. 2) Age, self-perceived labor intensity, and months of farming work were significantly higher in the pain group than those in the non-pain group. 3) Overall work-related musculoskeletal pain intensity (WPI) showed positive and negative correlations with years of farming experience and self-perceived health status, respectively. 4) In binary logistic regression, the occurrence of WMSP showed significant associations with self-perceived labor intensity. 5) On multiple linear regression analysis, age, months of farming work, and self-perceived health status had a significant impact on overall WPI. Conclusion: The WMSP of farmers in Tigray, Ethiopia was related to the characteristics of farm working and health status. Furthermore, HFWMP and AFWMP were the chief factors affecting the occurrence of WMSP in farmers in Tigray. Therefore, both HFWMP and AFWMP should be considered for clinical health assessments of farmers with WMSP in underdeveloped African countries.

• Journal of Korean Academy of Nursing
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• v.46 no.1
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• pp.39-49
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• 2016

Purpose: This study was done to develop a postural-stability patient transfer technique for care helpers in nursing homes and to evaluate its effectiveness. Methods: Four types of patient transfer techniques (Lifting towards the head board of the bed, turning to the lateral position, sitting upright on the bed, transferring from wheel chair to bed) were practiced in accordance with the following three methods; Care helpers habitually used transfer methods (Method 1), patient transfer methods according to care helper standard textbooks (Method 2), and a method developed by the author ensuring postural-stability (Method 3). The care helpers' muscle activity and four joint angles were measured. The collected data were analyzed using the program SPSS Statistic 21.0. To differentiate the muscle activity and joint angle, the Friedman test was executed and the post-hoc analysis was conducted using the Wilcoxon Signed Rank test. Results: Muscle activity was significantly lower during Method 3 compared to Methods 1 and 2. In addition, the joint angle was significantly lower for the knee and shoulder joint angle while performing Method 3 compared to Methods 1 and 2. Discussion: Findings indicate that using postural-stability patient transfer techniques can contribute to the prevention of musculoskeletal disease which care helpers suffer from due to physically demanding patient care in nursing homes.

• Journal of the Korean Society of Safety
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• v.5 no.3
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• pp.56-62
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• 1990

This study is conducted to analyze exact causes of occupational fatalities and results are as follows ： 1) The number of fatalities in establislment which employed less than 50 workers is 605(40.1％ ). Age of sixties and seventies is occupied by 10 percent with there being old-aged trend. Fatal workers who were employed less than 3 months are 39.5 percent and fatal workers who were employed more than 10 years are 11.9 percent. Safety training is necessary for newly recruited and long employed workers. 2) Accident type is, in sequence, fall from elevation, traffic accident, disease, contact with electric current, and hazardous condition is, in order, inadequate guard, hazardous method or procedure, public hazard, and agency of accident is, in sequence, temporary structure/building/structure, powered transport vehicle, passenger vehicle, hoisting or lifting apparatus, and unsafe act is, in order, driving error, failure to secure or warn. 3) The results of cross-tabulation for hazardous condition and accident type is, in sequence, traffic accident by public hazard, fall from elevation by hazardous method or procedure, fall from elevation as well as contact with elctric current by inadequate guard. The result of cross-tabulation for agency of accident and accident type is, in order, fall from elevation by temporary structure/building/structure, traffic accident of passenger vehicle and powered transport vehicle, contact with electric apparatus. The result of cross-tabulation for agency of accident and hazardous condition is, in sequence, public hazard of passenger vehicle, hazardous method or procedure of temporary structure/building/structure, publit hazard of powered transport vehicle, inadequate guard of temporary structure/building/structure. The result of cross-tabulation for unsafe act and accident type is, in sequence, traffic accident by driving error, fall from elevation by inattention to footing or surrounding, contact with electric current by secure or warn.

• Journal of the Ergonomics Society of Korea
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• v.30 no.3
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• pp.409-418
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• 2011

Objective: This study was performed to evaluate the child-care teachers' job in relation to physical work. Background: Child-care teacher is directly related to the quality of child care. And their physical activity is higher than general education teachers because the proportion of day care is high. But analyzes of child-care teachers' job burdens and the work environment associated with physical activity is not well established. Method: To conduct this study, the child-care teachers' job was classified into 18 physical works. After classification, posture was evaluated by ergonomic posture evaluation schemes of OWAS, RULA, REBA and evaluated for each physical part. Next, musculoskeletal subjective symptoms were analyzed. Results: The results showed the following: The highest assessment on the posture evaluation was "helping children to ride a school bus", "feeding: meal/snack", "brushing children's teeth" and "arrangement of nap-stuff". The rank of high-risk assessment on the neck/trunk/leg part was arranged by: "feeding: meal/snack", "helping children to ride a school bus", "making nap", "arrangement nap-stuff" and "brushing children's teeth". The rank of high-risk assessment on the upper limbs part was arranged by: "helping children to ride a school bus", "the bust - group activity", "meal/snack time - preparing, feeding, arrangement", "nap time - preparing, arrangement", "brushing children's teeth", and "using the toilet". According to the results of each musculoskeletal subjective symptom, teachers ordered the pain area as follows: waist, shoulder, leg/feet, and neck, and they showed more pain on trunk than the upper limbs. Conclusion: To sum up the results from ergonomic posture evaluation and a subjective symptom, the following are high working pressures: "feeding: meal/snack", "the bust - group activity", "making nap", "brushing children's teeth" with deep bending and waist twisting, "helping children to ride a school bus", "brushing children's teeth" with lifting shoulder; "meal/snack time - preparing, arrangement", "nap time - preparing, arrangement", and "using the toilet" with moving or an up-down position in their job. Application: The results of this study might be information for improvement of the child-care teachers' job environment.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.3
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• pp.21-32
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• 1992

Numerical solutions are presented for solving the free surface flow created by a three-dimensional body moving beneath the free surface with constant velocity at an angle of attack. The solution is obtained using a panel method based on the perturbation potential, which employs Havelock sources and normal dipoles distributed on the body surface and Havelock normal dipoles in the wake downstream of the trailing edge. A pressure Kutta condition with an iterative solution procedure is implemented to satisfy equal pressure condition on the upper and lower surfaces at the trailing edge. Numerical calculation examples in the present paper include an ellipsoid at zero angle of attack, a rectangular planform wing at a small angle of attack in the limit of zero Froude number and then free surface flows and hydrodynamic forces acting on the submerged spheroid and parabolic strut are calculated. Discussions are made about the validity of the present method.