• Korean Journal of Applied Biomechanics
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• v.29 no.2
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• pp.79-88
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• 2019

Objective: The aim of this study was to determine the peak torques of the knee and ankle joint and local stability of the lower extremity's joints, and muscle activation patterns of the lower extremity's muscles between fallers and non-fallers in the elderly women during walking. Method: Four elderly women (age: $74.5{\pm}5.2yrs.$; height: $152.1{\pm}5.6cm$; mass: $55.3{\pm}5.4kg$; preference walking speed: $1.19{\pm}0.06m/s$) who experienced falls within six months since experiment had been conducted (falls group) and thirty-six subjects ($74.2{\pm}3.09yrs.$; height: $153.6{\pm}4.9cm$; mass: $56.7{\pm}6.4kg$; preference walking speed: $1.24{\pm}0.10m/s$) who had no experience in falls (non-falls group) within this periods participated in this study. They were measured torque peaks of the knee and ankle joint using a Human Norm and while they were walking on a treadmill at their natural pace, kinematic variables and EMG signals were collected with using a 3-D motion capture system and a wireless EMG system, respectively. Lyapunov Exponent (LyE) was determined to observe the dynamic local stability of the lower extremity's joints, and muscles activation and their co-contraction index were also analysed from EMG signals. Hypotheses between falls and non-falls group were tested using paired t-test and Mann-Whitey. Level of significance was set at p<.05. Results: Local dynamic stability in the adduction-abduction movement of the knee joint was significantly lower in falling group than non-falling group (p<.05). Conclusion: In conclusion, muscles which act on the abduction-adduction movement of the knee joint need to be strengthened to prevent from potential falls during walking. However, a small number of samples for fallers make it difficult to generalize the results of this study.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.1
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• pp.165-173
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• 1997

The present study investigates heat/mass transfer for flow through perforated plates for application to combustor wall and turbine blade film cooling. The experiments are conducted for hole length to diameter ratios of 0.68 to 1.5, for hole pitch-to-diameter ratios of 1.5 and 3.0, for gap distance between two parallel perforated plates of 1 to 3 hole diameters, and for Reynolds numbers of 60 to 13, 700. Local heat/mass transfer coefficients near and inside the cooling holes are obtained using a naphthalene sublimation technique. Detailed knowledge of the local transfer coefficients is essential to analyze thermal stress in turbine components. The results indicate that the heat/mass transfer coefficients inside the hole surface vary significantly due to flow separation and reattachment. The transfer coefficient near the reattachment point is about four and half times that for a fully developed circular tube flow. The heat/mass transfer coefficient on the leeward surface has the same order as that on the windward surface because of a strong recirculation flow between neighboring jets from the array of holes. For flow through two perforated plate layers, the transfer coefficients on the target surface (windward surface of the second wall) affected by the gap spacing are approximately three to four times higher than that with a single layer.

• Journal of Energy Engineering
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• v.14 no.4 s.44
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• pp.213-218
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• 2005

In order to understand the heat and mass transfer characteristics of humid airflow in frosting conditions, a flat plate of aluminum with cooling modules located in the central part of the plate was used. A microscope system (resolution of 0.05 mm) was used for the measurement of local thickness of frost at seven points along the plate in the flow direction. For the total mass of frost at each test operation, an electronic balance (resolution of 1 mg) was used. The local frost thickness distributions far various test conditions were presented along with the frost mass data measured at the given operating times. The effect of humidity and velocity of humid air on frosting were analyzed.

• Journal of Chest Surgery
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• v.33 no.4
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• pp.333-337
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• 2000

Malignant fibrous histiocytoma(MFH) is a deep-seated pleomorphic sarcoma, which occurs principally as a mass of the extremities, abdominal cavity, or retroperitoneum in adults. However, it only rarely occurs in the chest wall. An 85-year-old man had undeergone excision of a small mass on the right posterior chest wall under local anesthesia 14 months age. However, the lesion did not heal and the mass recurred. He was referred to our hospital after the mass had grown to a size of 10.5$\times$8$\times$4cm with a 3$\times$3cm skin defect. Intraoperative frozen biopsy revealed MFH. An en-bloc wide resection and thin-thickness skin graft from his thigh were performed. Although distant metastasis to the lund developed 14 months later and the patient died 2 months later, there was no local recurrence. Thin-thickness skin graft is a simple method for a wide range skin defect, especially in the old age. He recovered in good condition without any physical disabilities.

• The Journal of the Korean bone and joint tumor society
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• v.4 no.2
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• pp.88-93
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• 1998

Neurilemoma usually discovered incidentally, is a benign nerve-sheath tumor which has been described as a painless mass. In most cases, the size of the mass was smaller than 5cm. However, it was reported that there were masses, sometimes associated with local tenderness and pain, whose size was over 6cm. Then, we have found there is a relationship between mass size and neurologic symptoms, as well as with, postoperative complications. It is important to diagnose early and to treat it. Twenty neurilemoma patients, who were treated at Keimyung University Dongsan Medical Center were analyzed using their clinical symptoms, pathologic findings, radiologic findings and complications. There was no sexual difference in tumor incidence. The anatomical locations of tumors were as follows. ; upper extremities in 15 cases(69%), axilla in 1 case(4%) and lower extremities in 6 cases(27%). Symptoms were palpable mass in 22 cases, local tenderness in 8 cases(36%), radiating pain in 6 cases(27%) and paresthesia in 6 cases(27%), Median nerve was involved most frequently(33%). There were 2 patients(10%) with multiple symptoms. Tumor enucleation was done in all cases. The size of tumors in longest axis was smaller than 2cm in 2 cases, between 2 and 4cm in 11 cases and more than 5cm in 9 cases. There was no case of malignant transformation or recurrence. In conclusion, incidence of clinical symptom and postoperative complications are increased with the size of the tumor especially over the 5cm. Preoperative MRI finding was the most accurate method of diagnosis and most helpful in determining surgical resection margin.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.2
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• pp.216-224
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• 2001

Experiments have been performed to investigate evaporative heat transfer characteristics of R-134a flowing in a small diameter tube. Test section was made of stainless steel tube with an inner diameter of 2.2mm and was uniformly heated by electric current which was applied to the tube wall. The local saturation temperature of refrigerant flowing in a tube is calculated from the measured local saturation pressure by using an equation of state. Inner wall temperature was calculated from measured outer wall temperature, accounting for heat generation in the tube and one dimensional heat conduction through the tube wall. Mass quality of refrigerant flowing in a tube was calculated by considering energy balance in the pre-heater and the test section. Heat flux was varied from 19 to 64kW/$m^2$, and mass flux was chanted from 380 to 570kg/$m^2$s for each heat flux condition. From this study, heat transfer in a small diameter tube is affected by heat flux as well as mass flux for a wide range of mass quality. Heat transfer coefficient in a small diameter tube is much greater than that in medium sized tubes. Test results in this study are compared with Gungor and Winterton correlation, which gives an absolute average deviation of 27%.

• Archives of Craniofacial Surgery
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• v.12 no.1
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• pp.63-66
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• 2011

Purpose: Cranial fasciitis is a rare type of benign tumor that occurs mostly in children younger than 6 years. It arises from the deep fascia, periosteum, or fibromembranous layer that covers fontanelles. The etiology is unknown, although prior trauma has been postulated to be an underlying cause. There is a 2:1 male predominance. Despite its rapid growth, this tumor has a benign clinical course and can be cured by total excision. Methods: A 16-year-old male presented with a 3 cm-sized palpable mass in the left lateral eyebrow region that he first noticed 4 months before presentation. The mass had grown rapidly since it was first noticed. Preoperative brain computed tomography showed a well-demarcated mass approximately 3 cm in size extending from the subcutaneous layer to the periosteum. Preoperatively, the presumed diagnosis was a dermoid cyst. An operation was performed with the patient under general anesthesia. The subcutaneous mass was completely excised by periosteal dissection. Results: Histological diagnosis revealed the presence of cranial fasciitis. After 20 months of follow-up, there have been neither complications nor evidence of local recurrence besed on clinical examination. Conclusion: Although cranial fasciitis is quite rare, it should be considered in the differential diagnosis for lytic skull lesions in patient whose clinical presentation suggests this possibility. This condition could be occasionally mistaken for malignant or locally aggressive lesions. To prevent local recurrence, curettage of the underlying bone is recommended for patients with bone involvement.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.2
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• pp.141-150
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• 2009

When constructing a subsea tunnel in discontinuous rock mass, fluid flow in joints has a great influence on the behavior of the tunnel so that hydro-mechanical coupled analysis should be performed for the stability estimation. In practice, relaxed rock load is generally used for the design of tunnel concrete lining. In a continuum analysis, a method based on the distribution of local safety factor around a tunnel was proposed for the estimation of a potential relaxed zone. However, in the case of discontinuous rock mass in which joints are developed, the whole stability of tunnels depends on the behavior of the joints. In this study, therefore, a method is proposed for the estimation of a potential relaxed zone occurred by the excavation of a tunnel in discontinuous rock mass. The suggested method is validated by sensitivity analysis and the comparison with the results of continuum analysis.

• Korean journal of communication and information
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• v.52
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• pp.27-47
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• 2010

This study analyzes the latest statistics for 3 years based on the traits of market environment, internal organization characteristics(the size and distribution of workforce), and financial structure, and then, investigates the interactivity traits and drawbacks between organization and market environment, among the local broadcast stations, and, among the type of work in the internal organization, by interviewing with broadcasters working at the local stations. Major findings of this studies are : at first, statistically, the conditions of local market environment, the size of local station workforce, financial structure are very poor. And, the interactivity among the local broadcast stations have so many difficulties because of a conflict of interest. So, for getting over a difficult situation at the local stations, in addition to planning to support local stations with various policies, government and local stations should seek for solution to overcome the conflict of interest jointly.

• Korean journal of food and cookery science
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• v.25 no.4
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• pp.452-466
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• 2009

The aim of this study was to investigate the dietary attitude, popularization and merchandising intention of native local foods in the Yeongcheon area using a questionnaire. The questionnaire was answered by 322 citizens living in Yeongcheon. The findings are summarized as follows: 25.8% of the respondents stated that 'familiarity in taste' was the reason that they like local foods. 32.0% of the subjects said 'mass media' was the reason they knew about local foods. The most important aspect of local foods for tourism was 'taste' (44.7%). One of the main conditions for the popularization of local foods was 'holding various kinds of cultural events' (25.2%). The most recognized native local food in the Yeongcheon area was 'Ukhoe' (3.60 points), followed by 'Samsong-gun-mandu' (3.58 points), 'Dotorimuk-muchim', 'Hanu-sutbul-gui' and 'Chueotang'. On the other hand, the recognition score for 'Gompi-namul' (2.63 points), 'Piramijorim' (2.77 points), 'Sangeo-pipyeon', 'Muneochae-sukhoe' was very low. The most effective local food in developing tourism in Yeongcheon was 'Ukhoe' (3.70 points), followed by 'Hanu-sutbul-gui' (3.69 points), 'Dombaegi-gui-jjim', 'Samsong-gun-mandu', 'Someri-suyuk'. The results of this study indicate that the tourism commercialization intention of Yeongcheon local foods was significantly dependent on demographic factors (gender, age, education, dwelling period). Males had a high tourism product intention for 'Ukhoe', while female was high intention for 'Sogogi-jeongol' and 'Kongnip-kimchi'. The tourism commercialization intention for most Yeongcheon local foods increased as the dwelling period increased.