• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.123-129
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• 2013

Among various manual materials handling tasks, pushing/pulling was known to be one of the risk factors for the low back and shoulder musculoskeletal disorders (MSDs). This study was conducted to find out an optimal solution set of the handle height and distance for 4-wheel cart with two vertical handles. Ten male college students participated in the pushing force measurement experiment. The face-centered cube design, one of the central composite designs, was applied for the experiment, and the isometric voluntary pushing force was measured in 9 treatment conditions. The second order response surface model was predicted by using the pushing strength as a response variable, and the handle height and distance as independent factors. According to the 2nd order response model, the handle height and distance showed nonlinear relationship with the isometric pushing strength. To maximize the 2nd order response model (pushing force), the handle height and distance were optimized. The optimal handle height was 'xyphoid process height - stature', and the optimal handle distance was '$1.25{\times}shoulder$ width'. When calculated using the anthropometric data of the subjects of this study, the optimal handle height was $115.4{\pm}3.4$ cm, slightly higher than the elbow height, and the handle distance was $52.9{\pm}2.3$ cm.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.137-143
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• 2009

It has been reported that mechanical stimulation takes a role in improving eel/ growth in skeletal system. Various research groups have been showed their own bioreactors which stimulate cell-seed three-dimensional scaffold. In this study, we hypothesized that the various conditions of mechanical stimulation would affect cell growth and proliferation. To prove our hypothesis, we designed a custom-made bioreactor capable of applying controlled compression to cell-encapsulated scaffolds. This device consisted of a circulation system and a compression system. Each parts of the bioreactor was fabricated using the rapid prototyping technology By using the rapid prototyping technology, we can modify and improve the bioreactor very rapidly For dynamic cell-culture, cell-encapsulated agarose gel was fabricated in 2% concentration. We performed dynamic cell-culture using this agarose gel and developed bioreactor in 3 days.

• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.253-259
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• 2012

The purpose of this study was to determine how smartphone use posture affects biomechanical variables and muscle activities. Eleven university students(age: $22.2{\pm}2.6$ yrs, height: $176.6{\pm}4.7$ cm, weight: $69.5{\pm}7.5$ kg) who have no musculoskeletal disorder were recruited as the subject according to having experience in using the smartphone for more than one year. Angular velocity, muscle activity, and thumb finger pressure were determined for each trial. For each dependent variable, a one-way analysis of variance (ANOVA) with repeated measures was performed to test if significant difference existed among different three conditions (p<.05). The result showed that rotational angular velocity of the first metacarpal were increased in DESK posture compared with STAND posture during SU phase. The average nEMG values of FDI(First dorsal interosseous) were less in SIT and DESK posture compared with STAND posture during SR phase. These indicated that smartphone postures may effect the thumb ROM(Range of motion) and muscle activity. This has led to suggestions of the need for further kinetic and EMG analyses to evaluate best assess and characterize with smartphone use.

• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.237-242
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• 2012

The purpose of this study was (a) to develop carbon nanotube-based shock absorbers for reducing potentially harmful impact forces and excessive foot pronation, and (b) to briefly determine how the effects of carbon nanotube-based shock absorbers on biomechanical variance during drop landing. A university student(age: 24.0 yrs, height: 176.2 cm, weight: 679.5 N) who has no musculoskeletal disorder was recruited as the subject. Hardness, specific gravity, tensile strength, elongation, 100% modulus, tear strength, split tear strength, compression set, resilience, vertical GRF, and loading rate were determined for each material. For each dependent variable, a descriptive statistics was used for different conditions. The property test results showed that tensile strength, tear strength, split tear strength, compression set, and resilience in carbon nanotube-based shock absorbers were greater than general Ethylene Vinyl Acetate(EVA). These indicated that resistance against variable strength in developed carbon nanotube-based shock absorbers were greater than general EVA. In vertical GRF of CNTC was less than those of EVA during drop landing and loading rate of CNTC was greater than EVA. It seems that the use of CNT can be a effective way of reducing and controlling shock from impact.

• The Korean Journal of Rehabilitation Nursing
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• v.12 no.1
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• pp.5-15
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• 2009

Purpose: The purpose of this study was to explore the concept of deconditioning within the field of nursing allied health sciences. Method: The concept analysis method described by Walker and Avant(1995) was used. Critical attributes, antecedents, consequences, and empirical referents were identified. Also model, borderline, contrary and related cases were proposed. Results: The definition of concept 'deconditioning' was a decrease in the function of general system that occured after long periods of immobility and might be marked by frail upon return to normal conditions. The attributes of deconditioning were as follows; 1) the deconditioning was caused by lengthening of physical inactivity; 2) the deconditioning state was resulted by respiratory system, cardiovascular system, musculoskeletal system, hematologic system and generalized manifestation; 3) the deconditioning state could be reconditioned. 4) The reinforced functions by exercise could be compromised by physical inactivity. Conclusion: Deconditioning is important concept in nursing practice since it occurs commonly in any patients who lack physical activity for long time and affects many aspects of clinical outcomes, but it could be reversible by nurses' efforts.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.172-177
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• 2008

The epithelioid sarcoma is a rare high grade soft tissue sarcoma that affects young usually male, adults or adolescents. The most common localization is the hand and the forearm, followed by the leg and the foot. In most cases, the sarcoma grows slowly, involves the dermis, subcutis, or deeper soft tissues in the distal extremities. Epithelioid sarcoma is a slowly growing tumor with a high propensity for local recurrences and lymph node metastases. This neoplasm is likely to be confused with a variety of benign and malignant conditions. The treatment consists of wide surgical excision, chemotherapy and radiotherapy. We report the cases of 16-year-old girl with an epithelioid sarcoma on the lower extremity.

• Research in Community and Public Health Nursing
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• v.22 no.1
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• pp.33-44
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• 2011

Purpose: This study examined the characteristics and service utilization of home nursing care beneficiaries under the Korean Long-Term Care Insurance (LTCI). Methods: We used assessment data and claim data of National Health Insurance Corporation from July to August 2008. Data were composed of subjects who were the beneficiaries of home nursing care. Results; A total of 634 subjects were analyzed. Of the subjects, 57.1% were 75 years and over. The average score of nursing care need was only 0.71 and the percentage of those whose nursing care need score was zero was 58.0%. More than half of the subjects had partially dependent musculoskeletal conditions, and 75.5% had two or more comorbidities. A third of them usedonly home nursing care, and another third used both home nursing care and general home care at the same time. Those who needed sore care used the largest home nursing care benefits. Conclusion: Home nursing care of LTCI performs community-based healthcare services under LTCI. Throughout the past two years, however, it has not been active. Understanding the characteristics of its users is important in order to develop effective strategies for activating home nursing care.

• IE interfaces
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• v.17 no.2
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• pp.218-225
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• 2004

This study aims to investigate effect of external load and motion repetitiveness on perceived discomfort. An experiment was performed for measuring discomfort scores at varying conditions, in which external load, motion repetitiveness and arm posture were employed as experimental variables. The arm posture was controlled by shoulder flexion and abduction, and by elbow flexion. Fifteen healthy college-age students without history of musculoskeletal disorders voluntarily participated in the experiment. The results showed that the effect of external load, motion repetitiveness and shoulder posture on discomfort were statistically significant, but that elbow posture did not significantly affect discomfort ratings. The effect of external load was much larger than that of any other variables, and that of repetitiveness was second only to external load. Discomfort scores significantly increased linearly as the levels of external load and motion repetitiveness increased. This implies that although they were not fully reflected in the existing posture classification scheme such as OWAS, RULA, etc., the effect of external load and motion repetitiveness should be taken into consideration for precisely quantifying work load in industry. Based on regression analysis, equivalent values of external load and motion repetitiveness in terms of discomfort scores were provided, which would be useful for better understanding the degree of their effect on work load.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.2
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• pp.167-173
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• 1998

Many workers like welders work in squatting postures with the object on the ground during an entire work shift. It is suspected that such prolonged squatting without any supporting stool would gradually cause musculoskeletal injuries to workers. This study is to examine the physical stress caused by the prolonged squatting and to recommend a safe work/rest schedule for a welding task with squatting posture based on the lab experiments. In this study, 8 healthy student subjects participated in the experiment. They maintained a squatting work posture for 16 minutes with 4 different stool height conditions: no stool; 10cm height; 15cm height; and 20cm height. Every 2 minutes, the discomfort was subjectively assessed with the magnitude estimation method for the whole body, lower back, upper leg and lower leg. Based on discomfort ratings, we found that a 10cm height stool relieved the workload most. Discomfort rating results also indicated that a 20cm height stool showed the highest workload, and the there were no difference in workload between a 15cm height stool and no stool. We recommend to use low height stools and to maintain such working postures no longer than 6 minutes for prolonged squatting tasks.

• The Korean Journal of Pain
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• v.29 no.2
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• pp.136-140
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• 2016

Myofascial pain syndrome (MPS) is one of the common musculoskeletal conditions of the shoulder which may develop sensory-motor and autonomic dysfunctions at the various level of the neuromuscular system. The pain and dysfunction caused by MPS were primarily treated with physical therapy and pharmacological agents in order to achieve painfree movements. However, in recent years intramuscular electrical stimulation (IMES) with conventional electrode placement was used by researchers to maximise therapeutic values. But, in this study an inverse electrode placement was used to deliver electrical impulses intramuscularly to achieve neuro-modulation at the various level of the nervous system. Nine patients with MPS were treated with intramuscular electrode stimulation using inversely placed electrodes for a period of three weeks. All nine subjects recovered from their shoulder pain and disability within the few weeks of intervention. So, this inverse electrode placement may be more appropriate for chronic pain management.