• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.143-152
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• 2005

The purpose of this study was to predict the failure or success of the Snatch-lifting trial as a consequence of the stand-up phase simulated in Kane's equation of motion that was effective for the dynamic analysis of multi-segment. This experiment was a case study in which one male athlete (age: 23yrs, height: 154.4cm, weight: 64.5kg) from K University was selected The system of a simulation included a multi-segment system that had one degree of freedom and one generalized coordinate for the shank segment angle. The reference frame was fixed by the Nonlinear Trans formation (NLT) method in order to set up a fixed Cartesian coordinate system in space. A weightlifter lifted a 90kg-barbell that was 75% of subject's maximum lifting capability (120kg). For this study, six cameras (Qualisys Proreflex MCU240s) and two force-plates (Kistler 9286AAs) were used for collecting data. The motion tracks of 11 land markers were attached on the major joints of the body and barbell. The sampling rates of cameras and force-plates were set up 100Hz and 1000Hz, respectively. Data were processed via the Qualisys Track manager (QTM) software. Landmark positions and force-plate amplitudes were simultaneously integrated by Qualisys system The coordinate data were filtered using a fourth-order Butterworth low pass filtering with an estimated optimum cut-off frequency of 9Hz calculated with Andrew & Yu's formula. The input data of the model were derived from experimental data processed in Matlab6.5 and the solution of a model made in Kane's method was solved in Matematica5.0. The conclusions were as follows; 1. The torque motor of the shank with 246Nm from this experiment could lift a maximum barbell weight (158.98kg) which was about 246 times as much as subject's body weight (64.5kg). 2. The torque motor with 166.5 Nm, simulated by angular displacement of the shank matched to the experimental result, could lift a maximum barbell weight (90kg) which was about 1.4 times as much as subject's body weight (64.5kg). 3. Comparing subject's maximum barbell weight (120kg) with a modeling maximum barbell weight (155.51kg) and with an experimental maximum barbell weight (90kg), the differences between these were about +35.7kg and -30kg. These results strongly suggest that if the maximum barbell weight is decided, coaches will be able to provide further knowledge and information to weightlifters for the performance improvement and then prevent injuries from training of weightlifters. It hopes to apply Kane's method to other sports skill as well as weightlifting to simulate its motion in the future study.

• Journal of Sasang Constitutional Medicine
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• v.18 no.3
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• pp.64-74
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• 2006

1. Objectives and Methods A Study on the Characteristics of the Korean Adult Male Sound according to Sasang Constitution using PSSC with a Sentence. Sasang Constitutional Medicine(SCM) is the one of the traditional Korean Medicine. It classifies people into four categories like Taeyangin, Soyangin, Taeumin and Soeumin. The rule to classify is Appearance and Body Shape, Facial Appearance and Speech, Character and Talents and Diseases and Medications. This study was done to investigate the relationships between Voice and Sound parameters using PSSC(Phonetic System of Sasang Constitution) in a sentence. Experimental Participants were 195 Korean adult males including 1 Taeyangin, 37 Soyangin, 105 Taeumin and 52 Soeumin. Sasang Constitutional specialist used PSSC and Korean Medical Diagnosis to classify participants into four constitution. 2. Results In Pitch segment, Soyangin's Center freq.(4) was significantly high compared with Taeyangin and Taeumin groups. Soyangin's and Soeumin's Center freq.(6) was significantly high compared with Taeyangin and Taeumin groups. In APQ segment and Octave segment, there were no significant differences among four groups. In Shimmer segment, Taeumin's F Shimmer(1) and F Shimmer(2) were significantly high compared with Taeyangin and Soyangin groups. In Energy segment, Taeyangin's 2k-4k total sum, 2k-4k dev., C dev., C# dev. and D S.D. were significantly high compared with other groups. In Recording time segment, there was no significant difference among four groups. More Taeyangin cases and the other parameters are needed to determine constitution using PSSC and to make PSSC effective. 3. Conclusions From above result, there is the possibility of efficiency standard guide for constitution diagnosis by analyzation og voice.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.76.3-77
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• 2021

GMT secondary mirror system consists of 7 segmented adaptive mirrors. Each segment consists of a thin shell mirror, actuators and a reference body. The thin shell has a few millimeters of thickness so that it can be easily bent by push and pull force of actuators to compensate the wavefront disturbance of light due to air turbulence. The one end of actuator is supported by the reference body and the other end is adapted to this thin shell. One of critical role of the reference body is to provide the reference surface for the thin shell actuators. Therefore, the reference body is one of key components to succeed in development of GMT ASM. Recently, Korea Research Institute of Standards and Science (KRISS) and University of Arizona (UA) has signed a contract that they will cooperate to develop the first set of off-axis reference body for GMT ASM. This project started August 2021 and will be finished in Dec. 2022. The reference body has total 675 holes to accommodate actuators and 144 pockets for lightweighting. The rear surface has a curved rib shape with radius of curvature of 4387 mm with offset of 128.32mm. Since this reference body is placed just above the thin shell so that the front surface shape needs to be close to that of thin shell. The front surface has a concave off-axis asphere, of which radius of curvature is 4165.99 mm and off-axis distance is about 1088 mm. The material is Zerodur CTE class 1 (CTE=0.05 ppm/oC) from SCHOTT. All the actuator holes and pockets are machined normal to the front surface. It is a very complex challenging optical elements that involves sophisticated machining process as well as accurate metrology. After finishing the fabrication of reference body in KRISS, it will be shipped to UA for final touches and finally sent to Adoptica in Italy, in early 2023. This paper presets the development plan for the GMT ASM Reference Body and relevant fabrication and metrology plans.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.77.2-77
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• 2002

Human upright standing posture in the sagittal plane is studied, when it exposed in the antero-posterior vibration. A two link inverted pendulum model is considered and described its functional behavior in terms of ankle and hip joint according to the dominant joints that provides the largest contribution to the corresponding human reactionary motion. The data is analyzed, both in the time domain and the frequency domain. Subjects behave as a non-rigid pendulum with a mass and a spring throughout the whole period of the platform motion. When vision was allowed, each segment of body shows more stabilized.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.89-92
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• 2004

Precast Segmental method was developed in germany 1950's. This method has been adoptted in long span girder mainly owing to easy construction effect. But, so far, The limit exists that this method is constructed in a portion of span and hard conveyance and foundation. This study was performed to analysis behavior difference of two rectangular section girder, spliced girder that was jointed 5-sliced 0.8m segment and monolithic girder that was produced in one body 4m span.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.6
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• pp.911-923
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• 1995

The zone of expansion and contraction of arm surfaces was analyzed, the correlation between arm surface changes was studied, and ergonomic sleeve designs were presented in which the consideration of body surface changes is emphasized. Experiments were carried out which include 43 upper extremity segments, 21 motions and 35 female subjects. The major conclusions of the study are as follows : 1. As a sleeve drafting method, detailed measures should be applied on the base of the sensitivity of body surface changes. The range of arm surface changes can be divided into three zones : concentrated expansion zone, zone of little change, and contraction part. The maximum expansion zone was the upper part of elbow. 2. The correlations were higher in lengths than in circumferences. Arm lengths were mainly correlated with upper arms. The more detailed the arm surface was, the lower the correlations between surface changes were. So there was not a lot of relation between segment changes. Tendency of body surface changes depended on the anatomical structure of the upper extremity and the movements of arm muscles. 3. As an application of measures and ease, ergonomic sleeve designs weve presented in which arm surface changes were considered. Ergonomic sleeve designs are recommended for working clothes and sports wear.

• Journal of Korean Neurosurgical Society
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• v.55 no.1
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• pp.48-50
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• 2014

Brucellosis is caused by gram-negative, aerobic, non-motile, facultative, intracellular coccobacilli belonging to the genus Brucella. A 50-year-old man working as an employee was admitted to neurosurgery clinic with severe low back, radicular right leg pain and hypoesthesia in right L4-5 dermatomes for 2 months. Brucella tube agglutination (Wright) test was positive in serum sample of the patient with a titer of 1/640. Brucella melitensis was isolated from blood culture. X-ray and MRI of the lomber spine showed massive collapse of L4 vertebral body. Neural tissue was decompressed and then posterior L3-5 short segment transpedicular screw fixation and stabilization was performed. Brucella melitensis was isolated from microbiologic culture of pathologic specimen. Antibiotic therapy was given as doxycycline 200 mg/day and rifampicin 600 mg/day for 6 months. Brucellosis is a systemic zoonotic infection and still an important public health problem in many geographical parts of the world. Vertebral body collapse caused by brucellosis occurs very rarely but represents a neurosurgical emergency because of its potential for causing rapidly progressive spinal cord compression and permanent paralysis. Neurosurgeons, emergency department personnel as well as infectious disease specialists should always keep a high index of suspicion and include brucellosis in the differential diagnosis of vertebral body collapse.

• Fashion & Textile Research Journal
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• v.12 no.2
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• pp.194-202
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• 2010

There may be some problems in size fitness for ready-made-clothes purchasers with Obese body shape. The purpose of this study was to improve the wearing comfort of Junior-High School Girls' slacks by setting grading points and developing grading rules proper to the obesity. The subjects in this study was over 23 kg/m2 of the BMI. The subjects were 124 Junior-High School Girls of 12 to 14 year-old. The results of this study are as follows: (1) The size intervals of waist girth and hip girth were 3 cm and 4 cm respectively. The sizing system, which had frequencies more than 5%, was classified 8 cases. The majority segment is 76-97 size accounting for the 11.29% of subjects. (2) The measurements on 8 size from two groups after drawing slacks pattern on them revealed that the changed values of slacks front and back on the grading point marked are differ, indicating that it is needed to apply body shape. (3) The evaluation on the appearance for wearing slacks showed relatively high score, indicating that the grading between sizes within each group was effective. The studies on the body size distribution on each obesity pattern and on the setting size system reflecting characteristics of each body shape should be performed continuously.

• Fashion & Textile Research Journal
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• v.11 no.5
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• pp.771-778
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• 2009

There may be some problems in size fitness for ready-made-clothes purchasers with fatty body shape especially for them with abdominal obesity. The purpose of this study was to improve the wearing comfort of Middle-aged women slacks by setting grading points and developing grading rules proper to the abdominal obesity. The subjects in this study was over $25kg/m^2$ of the BMI, over 85cm of waist, and over 0.8 of WHR. A total of 176 Middle-aged women satisfyingthem were enrolled. The results of this study are as follows: (1) The majority segment is 85-94 size accounting for the 11.36% of subjects. (2) The measurements on 11 size from three groups after drawing slacks pattern on them revealed that the changed values of slacks front and back on the grading point marked are differ, indicating that it is needed to apply body shape and age specific grading rule. (3) The evaluation on the appearance for wearing slacks showed relatively high score, indicating that the grading between sizes within each group was effective. The studies on the body size distribution on each obesity pattern and on the setting size system reflecting characteristics of each body shape should be performed continuously.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.6
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• pp.502-508
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• 2012

An analytical model for a human body is important to predict muscle and joint forces. Because it is difficult to estimate muscle or joint forces from a human body, the objective of this study is the development of a reliable analytical model for a human body to evaluate the lower extremity muscle and joint forces. The musculoskeletal system of the human lower extremity is modeled as a multibody system employing the Hill-type muscle model. Muscle forces are determined to minimize energy consumption, and we assume that motion is constrained in the sagittal plane. Muscle forces are calculated through an equilibrium analysis while rising from a seated position. The musculoskeletal model consists of four segments. Each segment is a rigid body and connected by frictionless revolute joints. Muscles of the lower extremity are simplified to seven muscles with those that are not related to the sagittal plane motion are ignored. Muscles that play a similar role are combined together. The results of the present study are compared with experimental results to validate the lower extremity model and the assumptions of the present study.