• Journal of Korean society of Dental Hygiene
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• v.19 no.5
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• pp.665-676
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• 2019

Objectives: The purpose of the study was to analyze the association between indirect vision skills and neck, shoulder, and back pain in dental hygienists. Methods: This cross-sectional study included 85 dental hygienists working full-time at dental clinics. A survey was performed for musculoskeletal symptoms in the neck, shoulders, and back of the subjects. The O'Connor tweezer dexterity test was performed using a mirror to evaluate their indirect vision skills. For statistical analyses, the t-test and one-way analysis of variance were performed. Results: The neck was the most common region of musculoskeletal pain (89.4%). The most intense pain was experienced in the neck (70.6%) and right shoulder (60.0%). Neck pain (20.0%) caused the most interference with clinical practice. Indirect vision skills were lower in the group with severe pain in the left shoulder or with high interference in work due to the left shoulder pain (p=0.026 and p= 0.017, respectively) or right shoulder pain (p=0.004). Conclusions: In this study, neck pain was a major musculoskeletal symptom among dental hygienists, and poor indirect vision skills were associated with the development of shoulder pain. Therefore, to prevent such musculoskeletal symptoms, dental hygienists should become proficient in indirect visualization, which enables a balanced and neutral posture.

• Clinics in Shoulder and Elbow
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• v.10 no.2
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• pp.241-245
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• 2007

We report a case of an 86-year-old man diagnosed with bilateral elastofibroma dorsi who was managed conservatively after a two year follow-up. An elastofibroma dorsi is a benign, slow-growing tumor that is most often located in the inferior periscapular area in elderly patients. It should be considered to differentiate them from other soft tissue tumors located at the inferior periscapular region. Increased awareness of these characteristics will decrease the incidence of a misdiagnosis of elastofibroma dorsi as a malignancy and avoid unnecessary surgery.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.3
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• pp.194-201
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• 2021

Objectives: The purpose of this study was to identify the distribution of diagnostic disease among applicants for shoulder musculoskeletal disease. Methods: In 2020, 47 diagnostic disease applicants were investigated for sociodemographic, health, work, job, and diagnostic disease characteristics. The data were corrected through on-site visits and analyzed using descriptive statistics with SPSS WIN23.0. Results: Most of the applicants were male and elderly. They had high blood pressure(38.3%) and diabetes (21.3%), and the drinking rate and smoking rate were also high. The most common type of employment was daily workers, and it was confirmed that the working condition was poor due to excessive working hours and short rest times. Most of the applicants for shoulder diagnostic diseases were in the construction industry, and the most common diagnostic disease was a rotator cuff tear. Conclusions: It is necessary to develop a musculoskeletal disease prevention program suitable for construction workers to reduce their work-related disease. When establishing a program, business type, task, and diagnostic disease must be considered.

• Korean Journal of Human Ecology
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• v.21 no.2
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• pp.285-298
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• 2012

Considerable number of women are enjoying swimming, however, the chest-region of swimsuits including cup inserts are not stable during swimming. The purpose of this study was to explore alternate designs and methods of stabilizing the breast cup to the swimmer's body by using 3D technology to design and position the pad and cup pattern of the swimming suit. To position the pad optimally, a 3D pattern of a nude woman was divided into blocks and different reduction rates were applied to blocks around the outlines of the breast. Two types of 3D patterns were developed. The first, referred to as the 'basic 3D pattern' provided for the curved surface of the breast point to be maintained with the remaining slack distributed evenly along the neckline, armhole and side seam. The second, referred to as the '1/3 shoulder moved 3D pattern' ignored the curved nature of the breast point by overlapping, with the resulting position of the shoulder strip moved toward the center. Three women of corresponding size and body shape evaluated the two 3D pattern designs as well as the conventional 2D pattern style of swimsuit. Respondents rated the'the basic 3D pattern' design highest in terms of stability and easy of movement in the chest region.

• Journal of the Korean Society of Safety
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• v.19 no.4 s.68
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• pp.123-128
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• 2004

This study investigated effect of arm posture, repetition of wrist motion and external load on perceived discomfort. The arm postures were controlled by shoulder flexion, elbow flexion, and ist motions such as flexion, extension, radial deviation and ulnar deviation. An experiment was conducted to measure discomfort scores for experimental treatments using the magnitude estimation, in which the L16 orthogonal array was adopted for reducing the size of experiment. The results showed that while the effect of the shoulder flexion, repetition of wrist motion and external load was statistically significant at $\alpha=0.05$or 0.10, that of the elbow and wrist motions was not. Discomfor ratings increased linearly as levels of wrist repetition and external load increased. This implies that the existing posture classification schemes such as OWAS, RULA, which do not properly consider effect of motion repetition and external load, may underestimate postural load. Based on the regression equation for wrist repetition and external load, isocomfort region indicating the region within which discomfort scores were expected to be the same was proposed. It is recommended that when assessing risk of postures or developing new posture classification schemes, motion repetition and external load as well as posture itself be fully taken into consideration for precisely evaluating postural stress.

• Advances in aircraft and spacecraft science
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• v.4 no.4
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• pp.487-501
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• 2017

The main purpose of the paper is to analyze effect of geometrical parameters of the reentry capsules such as radius of the spherical cap, shoulder radius, back shell inclination angle and overall length on the flow field characteristics. The numerical simulation with viscous flow past ARD (Atmospheric Reentry Demonstrator), Soyuz (Russian) and OREX (Orbital Reentry EXperimental) reentry capsules for freestream Mach numbers range of 2.0-5.0 is carried out by solving time-dependent, axisymmetric, compressible laminar Navier-Stokes equations. These reentry capsules appear as bell, head light and saucer in shape. The flow field features around the reentry capsules such as bow shock wave, sonic line, expansion fan and recirculating flow region are well captured by the present numerical simulations. A low pressure is observed immediately downstream of the base region of the capsule which can be attributed to fill-up in the growing space between the shock wave and the reentry module. The back shell angle and the radius of the shoulder over the capsule are having a significant effect on the wall pressure distribution. The effects of geometrical parameters of the reentry capsules will useful input for the calculation of ballistic coefficient of the reentry module.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.829-837
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• 2001

Using Video Display Terminals(VDT) in the working environment often causes health complaints in the neck and shoulder region. This study was conducted on ten subjects, in order to investigate the change of electromyographic activities in the neck region(sternocleidomastoid muscle, upper trapezius muscle and erector muscle of cervical spine)with regards to the screen height and document holder position. A total of six different conditions of screen height and document holder position were measured during subjects performed a text-entry task for a duration of 10min. The raw EMG signal was transmuted into the root mean square(RMS). Two-way ANOVA for repeated measures was used to analyse the effects of the two factors. As a result, changing the screen height and document holder position has no effect on electromyographic activities in the neck region.

• Proceedings of the IEEK Conference
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• 2003.07e
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• pp.1887-1890
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• 2003

This paper presents a three-dimensional (3D) head pose estimation algorithm using the stereo image. Given a pair of stereo image, we automatically extract several important facial feature points using the disparity map, the gabor filter and the canny edge detector. To detect the facial feature region , we propose a region dividing method using the disparity map. On the indoor head & shoulder stereo image, a face region has a larger disparity than a background. So we separate a face region from a background by a divergence of disparity. To estimate 3D head pose, we propose a 2D-3D Error Compensated-SVD (EC-SVD) algorithm. We estimate the 3D coordinates of the facial features using the correspondence of a stereo image. We can estimate the head pose of an input image using Error Compensated-SVD (EC-SVD) method. Experimental results show that the proposed method is capable of estimating pose accurately.

• Transactions of Materials Processing
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• v.8 no.2
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• pp.178-187
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• 1999

The Cross rolling between flat jaws, as a kind of hot forging, is the forming method to make the axisymmetric multi-step shaft by its rotation and pressure between flat jaws which move in opposite direction. The purpose of this study is to propose the optimal geometric data for shape development of the forward forming region. All data described on this paper are quantified by experiment from initial shape design to final shape development. As the result, proper geometric data are proved that lenth of the first forming area in the forward forming region is 1.5 times larger than circumference of work-piece and the progress angle changes 3 times smoothly.

• Journal of the Korean Home Economics Association
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• v.19 no.3
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• pp.21-32
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• 1981

Clothing must have the individual beauty and the function that one can do one's body movement freely. therefore, from the human engineering view point, the exact measurement of the human body and the analysis of it's results must be applied to clothing because the arm works most. In this study, the skin surface of arm was investigated by shell made of Alginate of each movement. And by sometic method the rate of expansion and contraction of each section, inter-relation among the bust girth, axillary arm girth and scye girth and between the shoulder length right and the under axilla waist length were calculate4d. With these results, cap height, breadth of a sleeve and arm hole girth of existing sleeve pattern have been compared and analysed. The results are as follows; 1) According to the developmental figures of shell, the whole area change was small but that of shape was remarkable in M 4, 9, 13. The change of the Block 1 was particular. 2) Over arm length was contracted in all movements except M6 and under arm length expanded. The changes of sections a, b, c are large, while those of sections d, e are small. 3) In terms of latitudes, change of fore-arm region was small. The rate of scye girth varied from 14.3% of M13 to-5.6% of M2. The breadth of a sleeve expanded in all movements, and especially the front region expanded more than the back. 4) The relation between the shoulder length right and under axilla waist length, in all occasions, was contracted mutually, and one contracted, the other expanded. Therefore, in clothing construction when we consider the function of the arm it is better to widen the arm hole and the breadth of a sleeve at the same time than no widen the shoulder length by lowering the upper part of the upper side seam line.