• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.284-290
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• 2010

In this study, as one of the carbon dioxide ($CO_2$) adsorbents the aqueous potassium carbonate ($K_2CO_3$)/promoter mixtures were investigated. Equilibrium partial pressure ($P_{CO_2}^*$) and pressure change were measured by using VLE (Vapor-liquid equilibrium) equipment in the mixture solution at 60 and $80^{\circ}C$, respectively. Absorption capacity was estimated in the semi-batch absorption apparatus at 40, 60 and $80^{\circ}C$. We proposed to use homopiperazine (homoPZ), cyclic diamine compound as a promoter of $K_2CO_3$ solution, to prevent crystalline formation and increase absorption capacity of aqueous $K_2CO_3$ solution. The absorption capacity of $K_2CO_3$/homoPZ was compared with MEA, $K_2CO_3$ and $K_2CO_3$/piperazine (PZ). Based on the results, we found that the mixture solution containing homoPZ had lower equilibrium partial pressure than that of $K_2CO_3$ solution and the absorption rate was approximately 0.375-times faster at $60^{\circ}C$, 0.343-times faster at $80^{\circ}C$ than that of aqueous $K_2CO_3$ solution without homoPZ. $K_2CO_3$/homoPZ solution showed excellent CO2 loading capacity compared with MEA solution at $60^{\circ}C$.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.7
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• pp.239-247
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• 2014

The CTSIB (Clinical Test of Sensory Integration on Balance) using high sensitive pressure sensors is normally used to assess the sense of balance in hospital. It takes an objective measurement of the amount of sway that occurs in the body trunk by observing the change in the center of pressure (CoP) on the foot at the upright posture. In this paper, we would like to propose method to easily measure trunk sway in home. Although the Wii balance board(WBB) is used for games, it can measures the center of pressure, which is highly correlated. The Wii remote controller(WRC) is inexpensive compared to the WBB, but it has problems with estimation of trunk sway because it can't measure pressure directly like WBB. We collected data from 10 normal subjects (5 males, 5 females) from two devices in order to compare the CoP from WBB and the center of mass (CoM) from WRC. The results of WRC and WBB was similar when the data were analyzed by the convex hull and ellipse area.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.9
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• pp.563-570
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• 2017

Experimental and numerical studies were performed to investigate the performance and internal flow characteristics of a supersonic second throat exhaust diffuser (STED) with back pressure ($P_a$). An ejector system was used to vary the back pressure ($P_a$) conditions. The operating gas for the STED and the ejector was high pressure nitrogen at room temperature. When the back pressure ($P_a$) at a constant nozzle inlet pressure $P_0$) decreases, the pressure recovery location moves downstream. If the pressure ratio $P_0/P_a$) is the same, even if the nozzle inlet pressures $P_0$) are different, the diffuser's internal flow pattern and starting pressure ratio ($(P_0/P_a)_{st}$) are almost the same.

• The Journal of Korean Physical Therapy
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• v.21 no.4
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• pp.51-56
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• 2009

Purpose: This study examined the difference in the static balance ability according to the visual cues and postural tasks in normal subjects. Methods: Thirty participants (12 male, 18 female; mean age $24.63\pm1.43$ years) stood barefoot on a force platform in a one-legged stance, tandem Romberg stance and tandem Romberg with neck extension stance with a visual cue open and closes. The static balance was assessed by the center of pressure (CoP), surface electromyography root mean square (RMS) of the leg muscles according to the stance position. Results: In the CoP tests, the difference in the unit path length and circumference area was affected by the visual cue according to the stance posture (p<0.01). In the RMS tests, the difference in the tibialis anterior and medial gastrocnemius muscle was affected by visual cue in accordance with the stance posture (p<0.01). Conclusion: The visual cue and postural task affect the balance ability in normal subjects. Therefore, this study provides clinical evidence that the balance and postural control can be improved. Therapeutic intervention, such as an obstacle course, and a lower leg muscle performance program with a change in the base of support can affect the balance and postural control.

• YAKHAK HOEJI
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• v.56 no.5
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• pp.309-313
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• 2012

Antiobesity, hypotriglyceridemic and antihypertensive activities of isoflavone-free peptide mixture (black soybean peptide, BSP) were reported in our previous experiments. In the present study, angiotensin converting enzyme inhibitory (ACEi) activity was decreased in the aorta tissues of spontaneously hypertensive rats (SHRs) treated with BSP (1% in drink water) for 4 weeks, but not in serum. BSP administration significantly decreased ACE activity by 17.5% (from $33.2{\pm}4.5$ to $27.4{\pm}1.96$ mUnit/mg, p=0.0013) in aorta tissue hydrolysate. BSP treatment also decreased significantly mean blood pressure (BP) (from $213.0{\pm}16.96$ to $184.0{\pm}6.53$ mmHg, p<0.0001) as expected. These results indicate that BSP has antihypertensive activity as well as ACEi activity.

• Korean Journal of Exercise Nutrition
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• v.14 no.2
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• pp.95-101
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• 2010

The purpose of this study was to evaluate changes of body composition, cardio-respiratory function in ventilation threshold (VT) and maximal state exercise, systolic (SBP) and diastolic blood pressure (DBP) and serum nitric oxide (NO) production during acute reducing salt (RS) supplementation in college elite athletes. Variables of cardio-respiratory function during rest, ventilation threshold and maximal exercise was not shown a significantly difference between RS supplementation and non-supplementation, there was shown a significant increase in ventilation threshold time (p<0.05) and exhaustion time (p<0.05) during RS supplement compared to non-supplement. SBP and DBP were not shown a significant difference between RS supplement and non-supplement. This result suggests that acute intake of RS is not increased a blood pressure. Serum NO production was not significant difference in the RS supplement group, but it was shown a significantly increased levels (p<0.01, vs. recovery 30 min.) immediately after maximal exercise in the non-supplement group. This result suggests that acute intake of RS have important role in inhibition of serum NO production during maximal exercise. Conclusively, This study suggest that acute intake of RS was not influence in body composition variables, but it was positive effect in ventilation threshold time, exhaustion time, maintenance of blood pressure and inhibition of serum NO production in maximal treadmill exercise.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.7
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• pp.82-88
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• 1993

This paper describes fabrication of relative type capacitive pressure sensor to be in great demand for many fields. The fabricated sensor consists of two parts` a sensing diaphragm and a pyrox glass cover. The sensor size is 4.5${\times}3.4mm$^{2})$ and 400$\mu$m thick. To improve the nonlinearity, this sensor is designed a rectangular silicon diaphragm with a center boss structure, and in order to improve the temperature characteristics of the sensor in a packaging process, the sensing element is mounted on the pyrex glass support. Some suggestions toward the design and fabrication of improved sensors have been presented. The zero pressure capacitance, Co of sensor is 26.57pF, and the change of capacitance, ${\Delta}$C is 1.55pF from 0Kgf/Cm$^{2}$ to 1Kgf/Cm$^{2}$ at room temperature. The nonlinearity of the sensor output with center boss diaphragm is 1.29%F.S., and thermal zero shift and thermal sensitivity shift is less than 1.43%F.S./$^{\circ}C$and 0.14% F.S./$^{\circ}C$, respectively.

• Journal of Korean Academy of Nursing
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• v.40 no.3
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• pp.433-441
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• 2010

Purpose: This study was performed to identify effects of pneumoperitoneum on hemodynamic changes of hypertensive patients undergoing laparoscopic colectomy under general anesthesia. Methods: Data collection was done from January 2 to June 10, 2008. Seventy-six patients, including 38 hypertensive patients, who had taken antihypertensive drugs more than 1 month and 38 normotensive patients undergoing laparoscopic colectomy were enrolled in this study. The hemodynamic parameters were heart rate (HR), mean arterial pressure (MAP) and cardiac output (CO) which were measured 7 times from before induction of anesthesia to 5 min after deflation of the pneumoperitoneum. Collected data were analyzed using Repeated Measures ANOVA and Bonferroni comparison method. Results: HR in the hypertensive group was significantly decreased at deflation of the pneumoperitoneum and 5 min after deflation of the pneumoperitoneum (p=.012). MAP in the hypertensive group was not different from the normotensive group (p=.756). CO in hypertensive group was significantly lower than normotensive group (p<.001) from immediately after pneumoperitoneum to 5 min after deflation of the pneumoperitoneum. Conclusion: The results indicate that pneumoperitoneum during laparoscopic surgery does not lead to clinically negative hemodynamic changes in heart rate, mean arterial pressure or cardiac output of hypertensive patients, who have taken antihypertensive drugs for more than 1 month.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.404-409
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• 2014

In this study, the effects of high-pressure homogenizer treatment on the physicochemical properties of wheat bran from different areas were evaluated. The results showed that the high-pressure homogenizer process could effectively decrease particle size and loosen the microstructure of the wheat bran matrix. As the particle size decreased, the bulk density of wheat bran was significantly decreased (p<0.05) and the water-holding capacity, swelling capacity, oil-holding capacity, and cation-exchange capacity were substantially increased. In addition, microscopic analysis revealed the gradual disintegration of the original cell wall structure and the dissociation of bran tissues over the course of high-pressure homogenization treatment. Scanning electron micrographs showed that the process could also effectively separate out the structural components of wheat bran. These results suggest that the high-pressure homogenizer process is an effective method to modify the physicochemical properties of wheat bran and likely other cereal brans, which might provide potential fiber-rich ingredients for use in functional foods.

• Journal of the Korean Electrochemical Society
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• v.8 no.1
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• pp.37-41
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• 2005

We investigated the electrochemical properties and microstructure on the various argon deposition pressure $(P_{Ar})$ and the low annealing temperature $(400^{\circ}C)$ of $LiCoO_2$ cathodes, which deposited by R.F. magnetron sputtering. The microsuucture and composition of Lico02 thin film was changed as a function of $P_{Ar}$. The capacity and electrochemical properties were improved with Ph of $LiCoO_2$ thin films. The cycling reversibility and stability of thin film batteries were measured by cyclic voltammetry and the constant current charge-discharge. The physical properties of cathode films were analyzed by ICP-AES, XRD, SEM and AFM for composition, crystallization and surface morphology.