• Journal of the Korean Society for Precision Engineering
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• v.22 no.6 s.171
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• pp.70-75
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• 2005

Many researches have been focused on optimal designs of a pole shape in order to reduce cogging torques, which are generated between permanent magnets and slots. In this paper, an adaptive controller is proposed fur reducing the effect of cogging torques in servo motors. The controller stabilizes the control system and shows an excellent trajectory tracking performance compared to the conventional PD controller.

• The Journal of Korean Medicine
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• v.17 no.2 s.32
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• pp.277-290
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• 1996

This study was aimed to evaluate the anti-pain effect of Kamikuibitang in acetic acid method and the anti-ulceration effect of Kamikuibitang in indomethacin, aspirin and immobilization stress method in rats. The results were follows; 1. The anti-pain effects of Kuibitang and Kamikuibitang were decreased compared with those of control group. 2. In indomethacin and aspirin method, the anti-ulcerative effects of experimental groups were shown compared with those of control group. 3. In immobilization stress method, the anti-ulcerative effect of experimental groups was significantly shown compared with that of control group. 4. The serum gastrin levels of Kuibitang groups showed very significant decrease in indomethacin-induced and immobilization stress-induced ulcers. The serum gastrin levels of Kamikuibitang groups showed very significant decrease in indomethacin-induced, aspirin- induced and immobilization stress-induced ulcers. 5. The serum $V_{B12}$ levels of Kuibitang groups showed very significant increase in both indomethacin-induced and immobilization stress-induced ulcers. The serum $V_{B12}$ levels of Kamikuibitang groups showed significant increase in aspirin-induced and immobilization stress-induced ulcers whereas very significant increase in indomethacin-induced ulcer. According to the above results, it was concluded that Kamikuibitang had very significant anti-ulceration effect as well as anti-pain effect on gastric ulcer in rats.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.95-102
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• 2020

The purpose of this study is to test both the alignment theory and entertainment theory on family firms listed on the Pakistan Stock Exchange. To achieve these goals, we collected secondary data from 164 non-financial family firms in various sectors during 2014-18. These family firms are classified into two categories: family control firms and family owned firms. We take the audit fee and the audit quality as dependent variables while family control firms, family-owned firms, and family CEOs as independent variables. In addition, the study uses leverage, profit and export as control variables. To test the effect of the explanatory variables on the output variables, we use two econometric models, Ordinary Least Square and the Probit regression model. In addition, Huber Sandwich test is used to check the non-normality and heteroscedasticity of panel data. Contrary to the alignment effect, the study supports the entrenchment effect and advocates that family-controlled firms as well as family-owned firms are not conscientious regarding the selection of external auditors during their contracts with audit firms. They are less likely to pay high audit fees for good quality audit in Pakistan. Furthermore, the study shows a statistically significant and positive relationship between audit quality and audit fees.

• Restorative Dentistry and Endodontics
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• v.16 no.1
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• pp.216-225
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• 1991

The purpose of this study was to evaluate the desensitizing effect of potassium oxalate(Group I), sodium fluoride (Group II), and control group (Group III). The 120 teeth of 26 patients who had been complained dentinal hypersensitivity were divided into three groups by applicating agent. The observation was done before and immediately after treatment. The data were statistically analyzed and the results were as followed. 1. Potassium oxalate showed the best desensitizing effect to the stimuli, followed by sodium fluoride, control group, and there was a significant difference (p<0.05) in desensitizing effect among the groups. 2. Potassium oxalate showed the best desensitizing effect to the stimuli, followed by sodium fluride, control group on both cervical abrasion and gingival recession, and there was a significant difference (p<0.05) in desensitizing effect among the groups on both cervical abrasion and gingival recession. 3. There was no significant difference (p<0.05) in effect of the desensitization between cervical abrasion and gingival recession. 4. The scratch and air blast I were more effective in desensitiziation than other stimuli with significant difference (p<0.05). In view of the results mentioned above, it can be conceived that potassium oxalate is more effective than sodium fluoride on the reduction of dentinal hypersensitivity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.12
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• pp.703-714
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• 2009

One of the biggest problems in smoke control systems for high-rise buildings is stack effect, but there are no recognized methods or measures to solve the problem of stack effect as yet. The stack effect can be overcome by forming the uprising current inside the stair hall properly, but there is a limit to the height in supplying into the stair hall the smoke control air volume to be supplied to a floor in case of escape from fire. The limit to the height can be extended by over-coming the stack effect by pressurizing the stair hall and the ancillary room simultaneously. It can also be anticipated that the stack effect can be overcome by connecting the air supply shaft to the stair hall at the top. As a result of computer simulations using a network type of tool, it is found that adequate performance can be achieved by pressurizing the stair hall only for a building of 190m or less, and up to 360m when pressurizing the stair hall and the ancillary room simultaneously. In all those cases, however, an overpressure venting damper is required which operates within a suitable range for venting the overpressure outside.

• Journal of Integrative Natural Science
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• v.1 no.1
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• pp.19-23
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• 2008

Morus alba has been well known for its tonic effect or preventing of hypertension, aging, or diabetes mellitus in Asian countries. To evaluate the its effect on hair growth promotion, we performed the hair regrowth experiment with leaf, branch, root and fruit extract of Morus alba on animal model of C57BL/6 mouse. The hair regrowth effect was remarkable in the mouse treated branch and root extract (with what %), however, little effect on hair regrowth appeared on the mouse treated with leaf extract. Morus alba extract displayed antibacterial effects on Bacillus subtilis, Staphylococcus aureus, Pseudomonas and Candida albicans. These results indicated that branch and root extract of Morus alba could be applicable for hair regrowth or prevention of hair loss in human.

• International Journal of Advanced Culture Technology
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• v.7 no.2
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• pp.60-66
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• 2019

The purpose of this study was to compare the effect of educational smartphone app with the effect of learning using conventional paper material. We developed an educational app for nursing students to learn how to read blood pressure and how to take a pulse. Evaluated was the effect of the app-based education by measuring the short term memory (right after the education), the long term memory (a week later) and the satisfaction. 25 college nursing students participated for the experiment group using the app-based education and 25 for the control group using paper-based education. We applied for statistical analysis Fisher's exact test and Independent t-test. The satisfaction of the app user's appeared significantly higher than that of the paper material user's (t=2.322, p=0.024). The short term memory score was 0.23 points higher in the experimental group (6.46 points) than in the control group (6.23 points), which was not statistically significant (t =0.422, p =0.675). Similar result came for the long term memory (t=1.006, p=0.320). After adjusting for the effect of a college grade using ANCOVA, the effect on memory was significantly higher in the experiment group. There might be differences in learning ability between the experimental and the control groups.

• The Korean Journal of Food And Nutrition
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• v.35 no.3
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• pp.193-203
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• 2022

This study aimed to provide directions and implications for a future program by analyzing studies on diabetes programs from 2000 to 2020. Among the studies with control and experimental groups, the selected studies included ones that provided intervention to patients with diabetes and ones that contained descriptive statistics. Sixteen studies were selected to verify the effectiveness and homogeneity of the data coding meta-analysis. The overall effect size in the diabetes program combined estimate was 0.398 (95% CI: 0.268, 0.425, p=0.000). Among the dependent variables, fasting blood glucose (-0.616) and glycated hemoglobin (-0.442) showed median effect sizes, but the effect of fasting blood glucose was not statistically significant. In terms of the study design, non-randomized control trials (NRCTs) (-0.543) was more effective than randomized control trials (RCTs) (0.719). Among, the counseling and self-management program (-3.241) showed a very large effect size. Furthermore, the cognitive-behavioral (-0.828) and self-management (-0.482) programs were also found to have a positive effect on lowering fasting blood glucose. As the importance of diabetes management increases, further studies based on RCT should be actively performed, and differentiated and specialized diabetes intervention plans need to be established.

• Korean Journal of Organic Agriculture
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• v.6 no.2
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• pp.81-106
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• 1998

This study aims to point out what is the basic idea and principle of weed control in or-ganic farming. The korean organic agriculture gets a point in dispute on weed control, be-cause 1) they do not practice the Basic Standard of IFOAM and FAO/WHO Codex Guidelines(draft), and 2) Korean organic farming is defined quite differently from internationally recognized core aspects for organic agriculture. Organic farming, in Korea, is taken to mean just the replacement of chemical fertilizer by organic manure and a-voidance of agricultural chemicals without practicing on rotation, cropping system and so on. As a consequence, organic farmers in Korea are suffering from hard labor to control the weed. In the paper it is discussed on organical weed control method which are required in the Basic Standard of IFOAM and guidelined in the Organic Production Principles of FAO/WHO Codex draft, and furthermore the single or combination effect of those method are also discussed. In conclusion it is suggest the necessity, purpose, and effect of the introduction of the basic stan-dard to korean organic agriculture including organical weed control.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.119-121
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• 2005

The sliding-mode control technique could make a system unstable which external disturbance and uncertainty exists in. This paper suggests a robust sliding-mode control algorithm which can be applied to a linear system with parameter uncertainties. To reduce the chattering effect, the whole system is comprised of using a state variable in which the state's estimated value is added. The condition of estimated state results from state observer. The proposed control algorithm uses the optimal feedback controller following the dynamic system equation which consists of a state variable resulting from its own state variable, controller input, estimated state variable. Through comparison with the time optimal control algorithm using simulation, the suggested algorithm shows the improved stability and robustness while it manifests the fast tracking characteristics.