• Journal of Welding and Joining
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• v.6 no.4
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• pp.35-43
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• 1988

Welding residual stresses were calculated by two dimensional thermal elasto-plastic analysis using element method. Complicated plastic behavior during heat transfer was simulated with time. Fist, temperature distributions. To consider time varying behavior of material properties and loading and unloading processes, iterative calculation based on initial stiffness method was carried out. The method proposed by Yamata was used in time increment control which determined the accuracy of claculation. comparison with other caculated and experimental results shows fairly good agreement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.673-676
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• 2005

In this paper, we propose a improved control performance for autonomous mobile robot using the embeded system. The proposed PID(PPID) control method removes steady state error, and has good performance in transient response. The integral term in the proposed method accumulates error in increment section, inverses errors in decrement section, and increases the effect of integral coefficient around target. Therefore, the PPID control method decreases the overshoot, and makes settling time faster than general PID(GPID) control method. In order to verify the effectiveness of the proposed method(PPID), we simulated the position control of DC motor, and experimented the velocity control of autonomous mobile robot. The PPID control method demonstrated good control performance that decrease overshoot and settling time in simulation and experiments.

• Journal of Power Electronics
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• v.16 no.2
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• pp.798-804
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• 2016

This paper proposes a new operation and control strategy for Power-Assisted Wheelchairs (PAW) using one brushless DC (BLDC) motor. The conventional electrical wheelchairs are too heavy and large for one person to move because they have two electric motor wheels. On the other hand, the proposed PAW system has a small volume and is easy to move due to the presence of a single wheel motor. Unlike the conventional electric wheelchairs, this structure for a PAW does not have a control joystick to reduce its weight and volume. To control the wheelchair without a joystick, a special control system and algorithm are needed for proper operation of the wheelchair. In the proposed PAW system uses only one sensor to detect the acceleration and direction of PAW's movement. By using this sensor, speed control can be achieved. With a speed control system, there are three kinds of operations that can be done on the speed of a PAW: the increment of PAW speed by summing external force, the decrement of PAW speed by subtracting external force, and emergency breaking by evaluating the time duration of external force. The validity of the proposed algorithm is verified through experimental results.

• The Journal of Korean Physical Therapy
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• v.13 no.3
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• pp.537-549
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• 2001

The isometric torque of the elbow flexor and extensor muscles were measured for 6 seconds at a joint angle of 90$^{\circ}$ , in 10 normal subjects (control group) and 10 hemiplegic subjects(patient group), using the Cybex NORMTM System. The peak torque, the time to peak torque were measured for each exercise. In addition, heart rate and blood pressure were recorded simultaneously at rest and immediately following exercise completion at 1 and 3m mutes. Statistical analysis was performed using SPSS 8.0 for Windows software and mean and standard deviations were calculated. The results are as follows. 1) In the patient involved group. the isometric values for flexors and extensors were significantly lower than in the normal nondominant group(p<.05). 2) The extensor to flexor strength ratio in the isometric mode was 121.0% in the patient involved group compared with 78.7%in the normal nondominant group, a significant difference(p<.05). 3) The mean increment ratio was increased 19.0% for systolic blood pressure and 25.2% for disatolic blood pressure in the patient group. 4) The mean increment ratio was increased 36.0% heart rate in the patient group.

• The Journal of Korean Society for School & Community Health Education
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• v.16 no.3
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• pp.41-50
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• 2015

Objectives: The purpose of this study was to apply an effective oral health promotion program and effect for underprivileged lower grade students. This study attempted to resolve some oral health inequality issues by providing underprivileged children with an oral health action program designed to promote positive oral health maintenance habits. Methods: This study was carried from May to August of 2009 with 77(control group 27 subjects, experimental group 36 subjects) elementary school students selected among first to third graders attending regional welfare center's after school program in Seoul. To the control group, conventional education methods were applied. To the experimental group, newly designed program was conducted by three project experts(1 expert, 1 dentist, 1 dental hygienist). It consisted of 5 sessions and progressed with various activities. It was focused on achieving target knowledge and changing oral health behavior. In order to evaluate the designed educational program, learners' achievement was evaluated with implementing the questionnaire and one-on-one interviews. And also the oral health improvement was evaluated based on change of Patient Hygiene Performance(PHP) index. Results: Based on the results of learners' achievement, the experimental group showed the significant increment of the oral health knowledge by the relapsed time, and it maintained after finished the program(p<0.001). The patient hygiene performance index showed not significant changed(p>0.05), but 1 month later the control group showed an increment of the PHP score, but the experimental group showed a decrement of it. Conclusions: Oral health promotion program by project approach could give a long-lasting educational effect to the children and encouraged proper oral hygiene behavioral changes.

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.101-109
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• 2008

The content of chlorophyll a, b have generally increased for Fraxinus rhynchophylla and Fraxinus mandshuricain the order of month of June B>C and >D. Therefore we suppose the photosynthesis rate will increase if the moisture level is high and in regardless of the growth stage.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.231-233
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• 1994

We have studied a properly of N-docosyl pyridinium(TCNQ) Langmuir-Blodgett film at room temperature with the $NO_2$ gas-detection characteristics. As a result, we have found that their conductivities were increased by 6 times at 5 layers(about $250{\AA}$ thickness) LB film. However, their reproducibility was not able to be measured at room temperature. Therefore, we must find their working temperature which was able to activate gas-detection characteristics. The $NO_2$ gas response experiments under 200 ppm concentration in $50^{\circ}C$ show that :here are increment of electrical conductivity by 8 times and 100 seconds of response time, and 200 seconds of recovery times at $60^{\circ}C$.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.10
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• pp.458-463
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• 2006

The purpose of this work is to investigate the fundamental properties of the gradual muscle force potentiation. We investigated the dependence of force potentiation on both the pulse-amplitude and the pulse-duration with different ramp-up time. The experimental results showed that the force increment ratio (FIR) during constant electrical stimulation decreased with pulse-amplitude and also with pulse-duration. The FIR was greater with short ramp-up time in both the pulse-amplitude and pulse-width modulation. The feasible mechanism might be that the myosin light chain phosphorylation induces the force potentiation and it occurs only in the fast type muscle fibers which are recruited first. These observations indicate that muscle potentiation must be understood well for the accurate control of muscle force.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.4
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• pp.59-78
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• 2009

Objective : This study was designed to examine the effects of stem bark extracts of Cornus walteri Wanger on the lipid lowering, anti-oxidative activity and concentration of proinflammatory cytokines in hyperlipidemic rat. Methods : Male rats weighing $195.21{\pm}5.85g$ fed high fat diet for 8 weeks and 40 rats(above 400 g) were divided into 4 groups. Each groups were divided into a control group and 3 experimental groups. We fed a control group of rats a basal diet and administered normal saline(100 mg/kg, 1 time/1 day) for 4 weeks. And we fed each experimental group of rats Basal diet and administered an extract of Cornus walteri Wanger(100 mg/kg, 200 mg/kg, 300 mg/kg, 1 time/1 day) for 4 weeks. At the end of the experiment, the rats were sacrificed to determine their chemical composition. We measured lipid of plasma and liver, concentration of proinflammatory cytokines, anti-oxidative activity and gene expression. Results : 1. Concentration of plasma free fatty acid, LDL-cholesterol showed a tendency to decrease in Cornus walteri Wanger ext. groups. Concentration of plasma triglyceride, total cholesterol showed a significantly decrement in all Cornus walteri Wanger ext. group than that of control group. HDL-cholesterol showed a significantly increment in the 300 mg/kg Cornus walteri Wanger ext. group. 2. Concentration of liver total cholesterol showed a tendence to decrease in Cornus walteri Wanger ext. groups. Concentration of triglyceride liver showed a significantly decrement in all Cornus walteri Wanger ext. group than that of control group. 3. Concentration of plasma and liver TBARS showed a tendence to decrease in Cornus walteri Wanger ext. groups. The values of GSH-Px, SOD and CAT activity showed a significantly increment in the 300 mg/kg Cornus walteri Wanger ext. group than that of control group. 4. The values of plasma AST and ALT activity showed no significantly different in all treatment groups. 5. Concentration of plasma $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ showed a tendency to decrease in the Cornus walteri Wanger ext. groups. However the concentration of IL-10 in the 200 and 300 mg/kg Cornus walteri Wanger ext. groups showed a significantly increment than that of control group. Concentration of liver $IL-1{\beta}$, $TNF-{\alpha}$ and IL-10 showed no significantly difference in all treatment groups. However concentration of IL-6 in the 200 and 300 mg/kg Cornus walteri Wanger ext. groups showed a significantly decrement than that of control group. 6. In the analysis of RT-PCR, gene expression of $TNF-{\alpha}$, Apo-B, Apo-E and leptin in the Cornus walteri Wanger ext. groups showed a lower expression than that of control group. 7. The ratio of $TNF-{\alpha}$, Apo-E and leptin expression per $\beta$-actin expression in the 200 and 300 mg/kg Cornus walteri Wanger ext. showed a significantly decrement than that of control group. The ratio of Apo-B expression per $\beta$-actin expression in the 300 mg/kg Cornus walteri Wanger ext. showed a significantly decrement than that of control group. Conclusions : According to above results, in lowering lipid effect, antioxidative activity and antiinflammatory effect, the Cornus walteri Wanger ext. gives positive effect.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2027-2030
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• 2016

Objective: To investigate the effect of peripheral blood CD4 + CD25 + regulatory T cell on postoperative immunotherapy in patients with renal carcinoma. Methods: 38 patients with renal cell carcinoma were recruited, and 20 patients from the operation group purely underwent the radical nephrectomy therapy, 18 patients from the combined group successively underwent the radical nephrectomy therapy and IFN-${\alpha}$ adjuvant immunotherapy. Additionally, 12 healthy subjects were recruited in the same period of time and regarded as the control group. Flow cytometry was used to detect CD4 +, CD8 +, CD4 + CD25+ T lymphocyte subset content and the ratio of all parts in the pre-operative period, in the first post-operative week and in the third post-operative month, compare and analyze its variation trend. Results: The CD4+CD25+ T lymphocyte subset content of individual renal carcinoma patients was significantly higher than that of the control group, also increases with the progression in the tumor stage (P<0.05). The post-operative CD4 + CD25+T lymphocytes of individual operation group and combined group patients showed different degrees of increment, but the increment of the combined group was significantly lower than that of the operation group (P<0.05). For the combined group patients with less pre-operative CD4 + CD25+T lymphocytes, their levels would increase after the immunotherapy, while the pre-operative patients with more CD4 + CD25+ T lymphocytes were the opposite situation. Conclusion: The detection of peripheral blood CD4+CD25+ regulatory T lymphocyte subset can reflect the anti-tumor immune status of renal cell carcinoma patient body. It can contribute to predict the prognosis of immunotherapy and provide reference for the choice of renal carcinoma post-operative adjuvant immunotherapy.