• 동력기계공학회지
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• 제7권4호
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• pp.38-43
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• 2003

This paper proposes an optimum design problem of structural and control systems. taking a 3-D truss structure as an example. The structure is supposed to be subjected to initial static loads and time-varying disturbances. The structure is controlled by a state feedback $H_{\infty}$ controller to suppress the effect of the disturbances. The design variables are the cross sectional areas of truss members. The structural objective function is the structural weight. As the control objective, we consider two types of performance indices. The first function represents the effect of the initial loads. The second one is the norm of the feedback gain. These objective functions are in conflict with each other. Then, first, two control objective functions are transformed into one control objective by the weighting method. Next, the structural objective is treated as the constraint. By introducing the second control objective which considers the magnitude of the feedback gain, we can per limn the design which is robust in modeling errors.

• 산업경영시스템학회지
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• 제25권4호
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• pp.1-7
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• 2002

Statistical process control is used widely as an effective tool to solve the quality problems in practice fields. All the control charts used in statistical process control are parametric methods, suppose that the process distributes normal and observations are independent. But these assumptions, practically, are often violated if the test of normality of the observations is rejected and/or the serial correlation is existed within observed data. Thus, in this study, to screening process, the Combined Shewhart - CUSUM quality control chart is described and evaluated that used bootstrap method. In this scheme the CUSUM chart will quickly detect small shifts form the goal while the addition of Shewhart limits increases the speed of detecting large shifts. Therefor, the CSC control chart is detected both small and large shifts in process, and the simulation results for its performance are exhibited. The bootstrap CSC control chart proposed in this paper is superior to the standard method for both normal and skewed distribution, and brings in terms of ARL to the same result.

• 소음진동
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• 제7권5호
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• pp.811-817
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• 1997

This paper is concerned with the active vibration controller design for the grid structure based on the positive position feedback (PPF) and the strain rate feedback (SRF) control. A new control methodology by the combination of the PPF and SRF control can suppress all the modes of the structure theoretically and can be easily implemented with analog circuits. The underlying concept for the design of the new controller is that the SRF controller stabilizes the modes higher than the second mode and the PPF controller stabilizes the fundamental mode which is destabilized by the SRF controller. In order for the new controller to be implemented succesfully, the collocated control is necessary. To this end, the piezoceramic sensor and actuator are located as close as possible, thus realizing the nearly collocated control. The combined PPF and ARF controller proves its effectiveness by experiments.

• 설비공학논문집
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• 제16권2호
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• pp.184-193
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• 2004

The purpose of this study is to evaluate the performance of various control strategies in commercial buildings which have been operated by the variable air volume (VAV) system. Two buildings in Seoul were chosen for the field study. The one (D building) combined by LonWorks has the constant airflow of supply fan and the proportional control of VAV units (damper type). The other (S building) combined by DDC has the PI control mode of the supply fan and the floating control of VAV units (venturi type). In estimating thermal comfort and energy performance through control modes of PI, PID, and CAV in the supply fan, we could identify several energy efficient operating control strategies for the VAV system.

• Journal of Electrical Engineering and Technology
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• 제9권4호
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• pp.1196-1201
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• 2014

This paper presents an exploration on the effect of wind turbine contribution to the frequency control of individual systems that can be used for efficient power production in India. The research includes the study of Permanent Magnet Synchronous Generator (PMSG), in wind farms. The WTs are tested for inertia and for droop responses with intelligent fuzzy logic controllers (FLC) that choose Double Input Single Output (DISO) strategy that automatically sets gain constants, as well as combined responses for the WTs. Quantitative analyses are presented for the WTs for benefits and drawbacks including appropriate selection parameters. The analysis includes inertia, droop and combined inertia, droop schemes. The reconnaissance also incorporates inertia with FLC, droop with FLC, inertia and droop with FLC schemes for detailed study of WTs, so as to forecast and achieve proper frequency control. Moreover, the analysis provides the best suited method for frequency control in PMSG.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.414-420
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• 2011

A study was conducted to investigate the effects of the combined stressor induced by high stocking density with feed restriction on immunological parameters such as leukocyte differential counts and cytokine expression in laying hens. A total of forty White Leghorn laying hens were randomly allotted into the control (12 kg of body weight/$m^2$) and the stress (44 kg of body weight/$m^2$) groups, and then birds of the stress group were given 75% of voluntary intake of the control birds for 12-d on a daily basis. There was a significant decrease in body weight without affecting the relative weights of the liver and spleen after 12-d of the combined stressor. In hematological values, no significant difference in leukocyte differential counts including heterophils (H), lymphocytes (L), monocytes and H:L ratio was observed between the two groups. In cytokines, hepatic lipopolysaccharide-induced tumor necrosis factor-${\alpha}$ (LITNF-${\alpha}$) and inducible nitric oxide synthase (iNOS) expression levels in the stress group were significantly (p<0.05) higher compared with those in the control group. However, the expression levels of interleukin (IL)-4 and IL-6 in the liver were not affected by the combined stressor. Splenic LITNF-${\alpha}$ expression in the combined stressor group was significantly (p<0.05) up-regulated compared with that in the control birds. However, the combined stressor did not affect splenic IL-4, IL-6 and iNOS expression. In conclusion, the combined stressor caused by high stocking density with feed restriction enhanced some pro-inflammatory cytokines including LITNF-${\alpha}$ and iNOS in lymphoid and non-lymphoid organs of birds, suggesting that altered cytokine expression to given stressors can be another parameter that can be used in assessing stress responses of birds.

• 대한물리치료과학회지
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• 제26권3호
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• pp.1-7
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• 2019

Purpose: The purpose of this study was to investigate the effects of the Otago exercise combined with action observation training on changes of the brain activity of the elderly. Design: Randomized controlled trial. Methods: Thirty elderly women in the experiment were included. Participants were randomly assigned to the Otago combined with action observation training group, the Otago exercise group, and the control group (10 in each group). The Otago combined with action observation training group and the Otago exercise group performed the strength and balance exercises of the Otago exercise program for 50 minutes three times a week for 12 weeks. The Otago combined with action observation training group underwent additional action observation training for the Otago movement for 20 minutes three times a week. No intervention was performed in the control group. PolyG-1 (LAXTHA Inc., Daejeon, Korea) was used to measure the changes in the brain activity following intervention. One-way analysis of variance was used to compare the effects among the groups and a post-hoc test was performed. Results: The relative mu rhythms in the F3, C3, and C4 regions were significantly increased in the Otago combined with action observation training group. Relative beta wave activity in the Fp1, F3, F3, and C3 regions was significantly increased in the Otago combined with action observation training group (p<0.05). Conclusion: The results indicated that the Otago exercise combined with action observation training was effective for promoting the brain activity of the elderly.

• 대한의용생체공학회:의공학회지
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• 제33권4호
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• pp.194-201
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• 2012

This study was designed to investigate the effect of a combined stimulus which was composed of chiropractic massage and thermotherapy on the relief of mental and physical stress. Fifteen healthy male subjects were treated with three type of stimuli; control (without any stimulus), a single stimulus (only chiropractic) and a combined stimulus. To evaluate the effects of stimuli, visual analogue scale (VAS), trunk extension, electromyogram (EMG) on erector spinae muscle and electrocardiogram (ECG) were measured and analyzed before and after stimuli. In the control group, there were no significant changes in EMG root mean square (RMS) value and low Frequency/high Frequency (LF/HF) ratio (p > 0.05, p > 0.05). However, both stimulus groups showed significant increases in trunk extension and EMG RMS values (p < 0.05, p < 0.05), but significant decreases in LF/HF ratios (p < 0.05). Particularly the decrement rate in LF/HF ratio was significantly higher in the combined stimulus group than that in the single stimulus group (p < 0.05). Also, a significantly lower VAS was recorded after combined stimulus. Our findings indicate that the combined stimulus might not only improve flexibility and strength of muscle, but also active parasympathetic nerve activity. The combined stimulus may thus contribute to relieve the stress and to enhance the muscle function.

• 한방안이비인후피부과학회지
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• 제18권1호
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• pp.104-115
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• 2005

Sunjeonhwadok-Tang was a drug that treated carbuncle and cellulitis. So, the purpose of this study was to investigate effects of Sunjeonhwadok-Tang on the proliferation of cancer calls and immunocytes focusing around combined effects of anticarcinogen. We used Sunjeonhwadok-Tang extract(SHT) with freeze-dried, 8wks-old male balb/c mice and cancer cell lines(L1210, Sarcoma-180) for this Study. The proliferation of cells was tested using a colorimetric tetrazoliun assay(MTT assay). The results : 1. SHT was significantly showed cytotoxicity on the L1210 cell lines. 2. SHT was significantly increased proliferation of thymocytes and splenocytes in vitro. 3. In combined effects of SHT and vincristine(0.005 mg/kg), SHT was significantly inhibited proliferation of L1210 cell lines, but was not inhibited proliferation of Sarcoma-180 cell lines compared with positive control group. 4. In combined effects of SHT and vincristine(0.005 mg/kg), SHT was significantly increased proliferation of thymocytes and splenocytes compared with positive control group. 5. In combined effects of SHT and vincristine, SHT was significantly increased proliferation of thymocytes and splenocytes in normal mice. 6. In combined effects of SHT and vincristine, SHT was significantly inhibited proliferation of L1210 cells in L1210 cells transplanted mice 7. In combined effects of SHT and vincristine, SHT was significantly increased proliferation of L1210 cell in L1210 cells transplanted mice. The present author thought that SHT had action of anti-cancer and immuno-activity, and in combined effects of vincristine, SHT had recoverable effects on damage by anticarcinogen.

• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8603-8605
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• 2014

Objective: To assess the safety of Brucea javanica and Cantharidin combined with chemotherapy in treating patients with non-small-cell lung carcinoma. Method: A consecutive cohort of patients with NSCLC were divided into four groups: experimental group A treated with Brucea javanica injection combined with chemotherapy; experimental group B with Cantharidin injection combined with chemotherapy; experimental group C treated with Brucea javanica and Cantharidin injection combined with chemotherapy; and the control group receiving only chemotherapy. After more than two courses of treatment, safety, quality of life and side effects were evaluated. Results: The incidences of myelosuppression in groups A, B and C were lower than that in Control group (p<0.05), but without significant differences among A, B and C. Adverse effects on the gastrointestinal tract also were lower than in controls (p<0.05) without variation amnog the combined treatment groups. Conclusions: Brucea javanica or Cantharidin combined with chemotherapy could in both cases improve quality of life in our cohort of NSCLC patients without any increase in toxicity. However, further clinical experiments should be conducted to evaluate the efficacy of Brucea javanica and Cantharidin combined with chemotherapy for patients with NSCLC.