• Bulletin of the Korean Mathematical Society
• /
• v.61 no.1
• /
• pp.93-115
• /
• 2024

In this paper, the Gauge-Uzawa methods for the Darcy-Brinkman equations driven by temperature and salt concentration (DBTC) are proposed. The first order backward difference formula is adopted to approximate the time derivative term, and the linear term is treated implicitly, the nonlinear terms are treated semi-implicit. In each time step, the coupling elliptic problems of velocity, temperature and salt concentration are solved, and then the pressure is solved. The unconditional stability and error estimations of the first order semi-discrete scheme are derived, at the same time, the unconditional stability of the first order fully discrete scheme is obtained. Some numerical experiments verify the theoretical prediction and show the effectiveness of the proposed methods.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2002.11a
• /
• pp.130-130
• /
• 2002

• Applied Biological Chemistry
• /
• v.30 no.1
• /
• pp.65-70
• /
• 1987

In Girder to measure the pressure and weight decrease of drying sample during the vacuum drying process of food, sensing devices were designed and constructed with strain gauge. Microcomputer based vacuum drying system was made up of these devices interfaced to apple II microcomputer. The electrical output signal from vacuum sensor which constituted with Bourdon tube whereon strain gauge attached were digitalized and input to microcomputer through the MC 6821 interface I.C. chip. The relationship between read-out digital value (D) from microcomputer and readings of vacuum gauge (P, mmHg) was P=-146.136+3.620D'(r=0.9994) The pressure control of vacuum dryer was successfully conducted in the range of $400{\sim}600\;mmHg$ accuracy. The digitalized load cell output (D) could be correlated with the real weight (W, g) as W=-14,000+0.585D (r=0.9998) Drying curves of green red pepper under $64^{\circ}C$, $400{\sim}600\;mmHg$ was similar to those of red pepper and differently affected by the degree of vacuum pressure but was varied according to their shape (cut or whole). Moisture movement of green red pepper during the vacuum drying process was fitted to Page model. The empirical equations obtained were $M-M_e/M_o-M_e={\exp}\;(-0.0673{\theta}^{1.177})$ and $M-M_e/M_o-M_e={\exp}\;(-0.0655\;{\theta}^{1.477})$ for whole and cut green red pepper, respectively.

• Proceedings of the IEEK Conference
• /
• 1999.06a
• /
• pp.551-554
• /
• 1999

In this paper, we developed a radial pulse transducer that has strain-gauge cantilever type load cell for total pulse detection on chongu arterial. The transducer consist of load cell and driving electronic circuits. Load cell consist of cantilever and two metal film strain gauge. The Pressure signal from chongu artery is delivered to load cell using artery rider that attached to cantilever Therefore the pressure signal convert to voltage signals by the developed transducer As the results of experiment, the developed transducer has very good linearity at pressure to voltage conversion. The total pulse detection transducer can detected three kinds of chongu artery pulse with conveniently.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.6
• /
• pp.1541-1547
• /
• 2008

Because of good taste and quick cooking, the induction heating type pressure rice cooker is widely used. Since pressure is applied to oven structure, it should be necessary to check the safety evaluation. In this paper, strain gauge experiment is performed in order to evaluate the oven's strain and its result is compared with that of structural analysis. And water test is performed to evaluate the oven's permanent deformation. The result is also compared with that of structural analysis. By using these experiments and analyses the safety evaluation method of the oven is suggested.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.20 no.9
• /
• pp.2909-2915
• /
• 1996

Precise and accurate pressure measurements are obtained using deadweight piston gauges. Pressure distribution and elastic distortion in the piston-cylinder unit are the leading factors in determination of effective area. The distortion depends upon the pressure distribution in the clearance between piston and cylinder and those are coupled each other. Considering the viscosity pressure relation of oil and governing flow equation in the clearance, a new numerical iterative algorithm is developed. The disagreement between the monotonous and sharp pressure profiles is an indication that the pressure profile will be different for each piston and cylinder unit due to material variances.

• Journal of the Korean Vacuum Society
• /
• v.13 no.2
• /
• pp.54-58
• /
• 2004

Three hot cathode ionization gauges (HCIG) were used to study their responses of pressure measurements at the stainless steel high vacuum (HV) chamber around room temperatures. The pressure variations of HV measured by the three HCIGs between $20 ^{\circ}C$ and $26 ^{\circ}C$ were 5.0 %, 5.3 %, and 10.3 %, respectively. However, pressure differences between $21.5 ^{\circ}C$ and $22.5^{\circ}C$ were lower than the gauges uncertainty limits. The pressure variations of the HCIGs at the HV chamber was not directly affected by gauge characteristics, but pressure changes due to room temperatures.

• Tunnel and Underground Space
• /
• v.13 no.2
• /
• pp.125-137
• /
• 2003

Field measurements were carried out in this study to investigate the behavior of cut and cover tunnel such as the distribution and the magnitude of the earth pressure during back fill process. Three kinds of measuring instruments, such as the earth pressure load cell, the concrete strain gauge and the reinforcing bar meter of embedded type in concrete structure were installed and measured. Earth pressure load cells measured the outside forces acting on the tunnel lining with radial directions. Three load cells were installed at the crown, the right and the left shoulder of the tunnel, respectively. Three sets of reinforcing bar meter were installed in the double reinforcements of the tunnel lining and their locations were the same with the position of the earth pressure load cells. Concrete strain gauge was installed only one site of the upper compressive part at the tunnel crown. Based on the measurements, the deformation and the earth pressure acting on the tunnel lining were investigated with the back fill process. Considerations on the validity of the field measurements were paid.

• Physical Therapy Korea
• /
• v.18 no.4
• /
• pp.19-25
• /
• 2011

The aims of this study were to investigate the correlation between the electromyographic (EMG) activity of the abductor hallucis (AbdH) and the amount of pressure measured by a pinch gauge (PG), and to compare the EMG activity of AbdH and the pressure measured by the PG during short foot (SF) exercise in subjects with pes planus and in subjects with a neutral foot alignment. Fourteen subjects were recruited for this study (pes planus group=7; neutral foot alignment group=7). A surface EMG was used to collect AbdH activity, and a PG was positioned under the first metatarsophalangeal joint to measure the pressure produced by the first metatarsal head during the SF exercise. The AbdH activity and the pressure measured by the PG showed a positive good correlation (r=.80, p<.05). The EMG activity of the AbdH and the pressure measured by the PG were significantly lower for subjects with pes planus than for subjects with a neutral foot alignment (p<.05). Based on these findings, the PG can be recommended as an effective instrument for evaluating the performance of the AbdH. It may also be beneficial for monitoring how well the SF exercise is performed, and for providing visual feedback to patients with pes planus during SF exercise in a clinical setting.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.13 no.1
• /
• pp.63-68
• /
• 2004

Recently ER fluids are put to practical use in fluid power industry field. As only with electrical signal change to the valve in which ER fluid flowing, ER fluid flow is controlled, so devepment of simple ER valves have been tried. In this case a technical problem is to check the pressure drop caused from flow rate change in valves because the pressure drop is very small. In this study ER valves are designed and manufactured, and small pressure drop induced from flow rate change is checked by pressure transducer which is made with appling strain gage. The ER valves and pressure drop check method are considered to be applied to the fluid power industry.