• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.241-244
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• 1997

23 hallux valgus patients were evaluated with clinical examinations and plantar pressure distribution measurements. A masking method for detailed plantar pressure distribution analyses was suggested. With higher grade of hallux valgus, pressure, contact length & area, and impulse on metartasus were significantly increased. Localized pressure concentration is very important in foot diseases and appropriate plantar pressure distributions should be considered on any shoe design.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1278-1282
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• 2005

Air mattress is now used widely to prevent the pressure ulcer by reducing the localized pressure peaks. In this paper an air-cell mattress and its pressure control method based on an approximate anthropometric model are presented. The air-cell mattress has eighteen cylindrical air cells made of porous material allowing air leakage to contribute in reducing the development of pressure ulcer by lowering the pressure peak, temperature and humidity. To determine an optimal air-cell pressure appropriate for each user, we divide the parts of the body into four sections such as head, trunk, hip, and leg. Then, the pressure of each section is independently calculated from the weight of each part based on the individual body height and weight and the approximate anthropometric model. Air supply system for the air-cell mattress is implemented by using four electronic solenoid valves and an air compressor, and it is driven by a real-time micro-controller. The experimental results with seven subjects shows that the proposed air-cell mattress is effective for the prevention of the pressure ulcer.

• Journal of Powder Materials
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• v.28 no.6
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• pp.478-482
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• 2021

The effect of the process conditions of high-velocity oxygen fuel (HVOF) thermal spray coating on the porosity of the coating layer is investigated. HVOF coating layers are formed by depositing amorphous FeMoCrBC powder. Oxygen pressure varies from 126 to 146 psi and kerosene pressure from 110 to 130 psi. The Microstructural analysis confirms its porosity. Data analysis is performed using experimental data. The oxygen pressure-kerosene pressure ratio is found to be a key contributor to the porosity. An empirical model is proposed using linear regression analysis. The proposed model is then validated using additional test data. We confirm that the oxygen pressure-kerosene pressure ratio exponentially increases porosity. We present a porosity prediction model relationship for the oxygen pressure-kerosene pressure ratio.

• The Korean Journal of Pain
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• v.14 no.1
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• pp.32-36
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• 2001

Background: There is no reliable objective test for the diagnosis of myofascial pain syndromes. The aim of this study was to evaluate the usefulness of a pressure algometer for the diagnosis of the trigger points and for the evaluation of the treatment in myofascial pain syndromes (MPS). Methods: Twenty female patients with clinical MPS of shoulder were included in this study. Pressure pain thresholds were measured by a pressure algometer at three different sites including the trapezius, supraspinatus and infraspinatus before, and then the 1st, 3rd and 7th days after TPI. Results: Mean pressure pain thresholds were lower in patients with MPS in than normal volunteers in all the examined skeletal muscles. Mean pressure pain thresholds in patients with MPS were increased significantly after TPI in all the examined skeletal muscles. Conclusions: Pressure algometer can be used as relatively objective diagnostic tool for locating trigger points and to quantify the effect of TPI in MPS. However, more investigation is necessary.

• Elastomers and Composites
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• v.52 no.4
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• pp.309-316
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• 2017

In injection molding, the quality of an injection molded product varies greatly depending on the molding conditions. Many researche studies have been conducted on the quality analysis of molded parts according to the molding conditions such as injection pressure, injection temperature, and packing pressure. However, there have not been many studies on the V/P switchover timing. It is known that when a large pressure is applied to a cavity in the packing phase, the cavity pressure is most affected by the packing pressure. In addition, depending on the position (timing) of the packing pressure, it can have a direct influence on quality based on the shrinkage and dimensions of the molded parts. In this study, the change in pressure profile in the cavity according to the V/P switchover position is confirmed. A CAE analysis program (Moldflow) was used to simulate and analyze two models using the PC and PBT materials. In order to compare these results with the actual injection molding results, injection molding was performed for each V/P switchover position, and the correlation between simulation and experiment, especially for the shrinkage of molded parts, was evaluated.

• Journal of Powder Materials
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• v.5 no.4
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• pp.319-323
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• 1998

Powder forging with a back pressure was investigated for production of automobile and compressor parts made of a rapidly solidified Al-Si alloy powder. Disk-shaped green compacts made of a rapidly solidified Al-Si alloy powder were hot forged, and hubs were formed by loading back pressure on their top. The influences of the back pressure and die temperatures on forgeabiliy and properties of parts made of a rapidly solidified Al-Si alloy powder were examined. This method was also applied to the production of a scroll part. The results of these studies are summarized as follows : 1. A back pressure on the hub top is very effective for consolidation and preventing crack formation in the hub. 2. When a back pressure tess than 98 MPa is applied, the forging pressure increases by the same amount of the applied back pressure. With more than 98 MPa, the forging pressure increases further due to an increased friction at the hub side. 3. Die temperatures higher than approximately 670k are needed in order to consolidate well the hub top without cracks.

• The Journal of Internal Korean Medicine
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• v.22 no.4
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• pp.621-625
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• 2001

Objectives: We examined if their hematological status could be changed by blood loss in patients treated with bleeding pressure therapy. Methods: The patients were divided into two groups as follows: The Subject group(B) were 42 cases treated with bleeding pressure therapy. The Control group(N) were 43 cases treated with negative bleeding pressure therapy, We checked CBC & differ cell count of two groups. Results: The means of RBC, Hb count and Hct were slightly decreased after 1 week. but they were recovered after 2 weeks. Conclusions: These results indicate that Bleeding Pressure Therapy don't reduced RBC, Hb count and Hct in Patients.

• The Korean Journal of Pain
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• v.9 no.2
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• pp.363-367
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• 1996

Background: Recently postoperative pain control with continuous epidural analgesia has been increased. This study aimes to evaluate backpain following continuous epidural analgesia by pressure threshold meter (algometer). Methods: After informed consent, 50 ASA physical status I or II patients undergoing elective gynecologic surgery were selected. After placing epidural catheter, patients received morphine 0.05mg/kg with 0.25% bupivacaine 5 ml followed by continuous infusion of 0.125% bupivacaine 100 ml with morphine 4 mg for 48 hours. backpain was measured by pressure algometer over lumbar paraspinalis at the L4 level, 5 and 7 cm from the midline on preoperative, operation day, 1st, 2nd, 3rd, and 4th postoperative days. Results: Postoperative mean pressure thresholds of were higher than preoperative value (p<0.05). Conclusion: The continuous epidural analgesia dose not provide or aggravate postoperative backpain, but it must be evaluated for long term follow-up.

• Korean Journal of Applied Biomechanics
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• v.25 no.4
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• pp.475-482
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• 2015

Objective : The purpose of this study was to investigate mean plantar foot pressure, maximum plantar pressure and ground reaction force, and center migration path of pressure according to the type of trekking shoes for the development of shoes. Method : Subjects of the study averaged $22.10{\pm}2.05years$ of age. Their average height was $169.27{\pm}7.62cm$ and their average weight was $64.34{\pm}10.22kg$. The method of this study was administered measuring 50 steps, at once, 3 times at a speed of 4 km/h and using the data of 30 steps. Pedar-X system measured the mean foot pressure, maximum foot pressure, mean maximum force, and center migration path of pressure by subjects' position while walking. Statistical analysis was performed by SPSS 23.0 using a paired t-test. Results : Results of the study showed Nestfit trekking shoes lower foot pressure of both feet in mean foot pressure and maximum foot pressure. Nestfit trekking shoes showed high ground reaction force (p<.001) in the midfoot, and low mean ground reaction force in the rearfoot. The center migration path of pressure showed the Nestfit trekking shoes were more stable than flat insole trekking shoes. Conclusion : It can be concluded that wearing Nestfit trekking shoes spreads pressure efficiently and induces walking stability because Nestfit trekking shoes spread the pressure of the forefoot and rearfoot to the midfoot and the center migration path of pressure shows regularly.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1974_1975
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• 2009

The chairbound, handicapped person often requires a cushion to distribute the supportive forces over the largest area possible in order to reduce the risk of the development of a pressure sore. Pressure sores are areas of damaged skin caused by staying in one position for too long and can cause serious infections, some of which are life-threatening. When sitting upright, the greatest proportion of body weight is centerd over the ischial tuberosities. So, it is important that comfortable seating and largest distribution of pressure to prevent pressure sores. Therefore, the objective of this study was to develop the physical pressure measurement device and orthodontic chair to prevent pressure sores.