• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1025-1030
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• 2009

It is known that the classical tuning formula for typical PID controllers in general provides unsatisfactory results for industrial plants where the time delay exceeds the dominant lag time. For this reason, alternative strategies have been studied in order to cope with this problem and the most popular scheme is the Smith Predictor(SP). In this paper, the dynamic model of a unit apartment in the district heating system, which is the control process effected by the dead-time, is developed, and the on/off room temperature control method with the SP simulate using Matlab-Simulink. The simulation results show that the SP works effectively in outdoor temperature variation.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.764-766
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• 1997

This paper presents a DSM Monitoring Methodology which is able to evaluate the impact of DSM programs under processing. For an effective assessment of DSM programs, it is foremost necessary to examine the market characteristics on the specific end-use appliance according to the customer's adoption of DSM programs. The Proposed Monitoring system contains a diffusion process of high efficient end-use considering major factors of DSM impact such as, price, price elasticity and lifetime of end-use apparatus or appliance. The case study shows the propriety and necessity of DSM monitoring in order to diagnose the current state and provide a baseline of DSM policy

• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.161-170
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• 2007

Ozone from a pilot-scale ozone generator was treated on fermented pig liquid manure stored in a storage tank in order to reduce odor substances during the process of fermented liquid manure production. The group of ozone treatment showed one less than the organic matter compared that of the control. The preferable condition for characteristic changes was when the ratio of BOD to COD was less than 1.5. Ozone treatment showed better oxidizing power than control as it removed more suspended solids and had less methyl isobutyl ketone(P<0.05). Odor reduction measured by olfactory method was higher in ozone treatment than in control.

• Knowledge Management Research
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• v.23 no.4
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• pp.177-205
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• 2022

Small- and medium-sized enterprises (SMEs) have strong incentives to engage in open innovation to enhance innovation efficiency and effectiveness due to their 'liability of smallness.' Previous research examined the performance effects of various open innovation practices, but whether coupled open innovation practices positively affect SMEs' firm performance is somewhat controversial. To resolve the issue, this study examined the effects of coupled open innovation activities on SMEs' firm performance using Heckman's two stage model to control endogeneity of the firms' self-selection bias in open innovation engagement. This study used the Korean Innovation Survey (KIS) 2020 collected by the Science and Technology Policy Institute (STEPI), and tested the effects of SMEs' coupled open innovation activities, R&D and non-R&D cooperation, on their innovative and financial performance indicators. The results showed that SMEs' R&D cooperation positively affects the new-to-market (NTM) product innovation only. Moreover, SMEs' non-R&D cooperation has positive effects on the product innovation, business process innovation, new-to-the-market product innovation, and new-to-firm (NTF) product innovation. However, the results showed that both R&D and non-R&D innovation cooperation activities have no significant effects on SMEs' financial performance indicators. This study contributes to research on SMEs' open innovation and provides insights for SMEs' managers and policymakers.

• Proceedings of KOSOMES biannual meeting
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• 2007.11a
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• pp.35-41
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• 2007

An International Convention on the control of harmful anti-fouling system on ships(AFS Convention) was adopted on 5 October 2001 at Diplomatic Conference in London, and is expected to be presently effectuated with ratification of more than 25-member nations possessing about 25% of total world tonnage. This convention regulates the operation of harmful anti-fouling system and especially prohibits the use of organotin compounds contained in anti-fouling paint. Organotin compounds have a tendency to be easily extracted by specific solvents and have high polarity and low volatility as specific characteristics. This drives us to attempt of going through the process named derivatization that is required in analysis using a gas chromatography(GC). This study was conducted to determine the proper pre-treatment method, ethylation in comparison with hydridization on the analysis of tributyltin in organotin compounds and to verify the application of the method through the experimental analysis practically used anti-fouling paint and painted layer sample of the served ship.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.4 s.34
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• pp.111-121
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• 1999

Acne vulgaris, the most common skin disease. can be formed as only a few comedons or severe inflammatory lesions. The pathogenesis of acne involves various factors; excessive androgen, excessive sebum production, abnormal alteration of follicular epithelium, proliferation of Propionibacterium acnes, and inflammation. We investigated acne therapy using oriental herbs described in the Korean traditional medical book(Dong-ui-bo-gam). Oriental herbs(Angelica daurica, Arctium lappa, Coptidis rhizoma, and Glycyrrhiza glabra) were chosen based on their respective property of sebum control, anti-inflammatory activity, and anti-bacterial activity. We examined the effect of acne treatment, in terms of chemotactic inhibition, lipogenesis inhibition, and anti-bacterial activity for P. acnes. 1. Neutrophil chemotaxis assay; P. acnes secrete chemotactic factors and other pro-inflammatory extracellular products. Neutrophil chemotactic activity of P. acnes was measured by 48-well chemotaxis method. Angelica daurica clearly suppressed chemotactic activity of P. acnes. 2. Using sebaceous gland of hamster ear lipogenesis assay; Sebaceous lipogenesis was measured using ear biopsies by incubation or $C^{14}$-acetate in culture media. The $C^{14}$-labeled lipids were extracted and determined by liquid scintilation counting. Coptidis rhizoma markedly inhibited sebum production. 3. Anti-bacterial assay for P. acnes(MIC test); Glycyrrhiza glabra showed anti-bacterial activity. P. acnes did not develop resistance against Glycyrrhiza glabra. Retinoids are effectively to inhibit sebum production and regulate follicular keratinization process, with little anti-inflammatory activity. Angelica daurica suppressed neutrophil chemotaxis, Coptidis rhizoma inhibited sebum production, and Glycyrrhiza glabra showed anti-bacterial activity against P. acnes. A combined formulation of Angelica daurica, Coptidis rhizoma. and Glycyrrhiza glabra is expected to provide effective acne treatment.

• Journal of Korea Foundry Society
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• v.25 no.4
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• pp.168-172
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• 2005

In this study, the effects of chill layers occurred in shot sleeve on the molten metal filling were analyzed through computer simulation and the behavior of chill layers with temperature variation of shot sleeve set from 200 to $280^{\circ}C$ was also investigated. The simulation results showed the chill layers set in the in-gates during the injection process change the main filling direction and cause turbulent flow pattern, resulting in porosities inside the castings. The amount of chill layers with the increasing temperature of shot sleeve was considerably reduced. And particularly, at the setting temperature of $280^{\circ}C$ by heat control unit, the big reduction in chill layers, excellent trimmed surface and the highest densification were achieved, suggesting that as the optimal sleeve condition in diecasting, especially for the highly complex parts like valve body.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.6
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• pp.453-458
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• 2016

CFRP (Carbon Fiber Reinforced Plastic) and CFRP-metal stacks have recently been widely used in the aerospace and automobile industries. When CFRP is machined by a brittle fracture mechanism, defect generation behaviors are different from those associated with metal cutting. The machining quality is strongly dependent on the properties of CFRP materials. Therefore, process control for CFRP machining is necessary to minimize the defects of differently manufactured CFRPs. In this study, defects in drilling of CFRP substrates with a variety of fiber directions and resin types are compared with respect to thrust force. An experimental study on material interface detection is carried out to investigate its benefits in process control.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.77-78
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• 2000

We verified the charged static electricity on LCD glass influences upon the etching uniformity of dry etching process by plasma. In the TFT-LCD manufacturing process, we mainly paid attention to eliminate the static electricity for TFT reliability. The static electricity caused the serious ununiformity of etching surface profile and etching rate in the dry etch process. Through our experiment on the made static electricity from -200V to -1000V, it was confirmed that the static electricity on LCD glass caused the etching rate variation of $1.5%{\sim}15%$. We recommend the etching process equipment for LCD manufacturing have to establish the soft X-ray exposure module system for eliminating the static electricity inside the loading and unloading chamber.

• Journal of Technology Innovation
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• v.2 no.1
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• pp.89-115
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• 1994

Japanese firms have developed their own distinctive human resource management(HRM) practices for R&D scientists and engineers. These practices consist of homogeneity of work group, standardized in-house training programs, great standardization and company control of careers, and broad job rotation following the process of commercialization of developed technology. These practices facilitate human and informational exchange and sharing between basic laboratories and development departments as well as between R&D and marketing department which contribute to the ket competitive advantage of Japanese products. But recently Japanese firm are forced to change their HRM practices. They face some srious problems in continuing their long0standing strategy of being a rapid and skillful‘ technology follower’,drawing on the basic research performed in the advanced nations and embodying it in products that are produced with high quality at relatively lower cost. There is a growing trend of strengthening basic research among Japanese firms today. In accordance with the emphasis on basic research, Japanese firms have been adopting new HRM practices for scientists and engineers which are in the opposite direction of the traditional one. These newly developed practices stress on individual vitality rather than group cohesiveness from the fusion of individual difference. These include heterogeneity of work group, multiple career paths to be chosen by individuals, incentive plan based individual performance.