• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.11-23
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• 2006

This study was carried out to propose low types of green speed expectation models for fast putting green management by changing mowing height($4.0{\sim}2.5$ mm) and timing of rolling, dew removal and dew removal+rolling. Ball roll distance data were taken from the creeping bentgrass(Agrostis palustris Huds. 'Penncross') practice green of east course at the Lakeside C.C. in October 18, 2001 and May 25, 2002. Data were subjected to multi-regression analysis using Statistical Package for the Social Science. Among four types of green speed expectation models, the best multiple-regression equation for fast green management was as follows; $Y_4=4.171-0.225{\cdot}X_1-0.038{\cdot}X_2$ (where, $Y_4$ : green speed(m) after single dew removal+single rolling, $X_1$ : mowing height($4.0{\sim}2.5,\;X_2$ : passage of time ($0{\sim}8$ h.)). The equation[single dew removal by using sponge roller $\rightarrow$ single mowing at 3.0 mm height or less $\rightarrow$ single rolling] explained to provide fast green over 3.2 m (Stimpmeter readings required for USGA championship play) until the end of first round. Therefore, this cultural practice system was believed to provide fast putting green condition for professional golf tournament

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.2
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• pp.3-9
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• 2014

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2016.10a
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• pp.179-179
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• 2016

• Asian Journal of Turfgrass Science
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• v.13 no.3
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• pp.139-146
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• 1999

This studies was carried out to estimate the influence of mowing height, time lapse, rolling, and dew removal on green speed of putting green in Lake Side C. C. on 29, 30 Jun. 1998. The results were as follows. As mowing height increased, green speed tended to be decreased. After mowing, green speed tended to be decreased over the time, and appeared to be decrease significantly on the next day[Y=3.206-0.127.X1-1.41$\times$10-2.X4(Y=green speed, X1=mowing height, X4=time lapse)]. This suggests that the frequency of mowing must be increased to maintain the green speed. But, frequent mowing cause the turfgrass of putting green to be stressed. Rolling tended to increase green speed[Y=3.555-0.202.X1+0.111.X2(Y=green speed, X1=mowing height, X2=rolling)]. Thus, rollers is thought to be an tool used to increase green speed and rolling is expected to be able to decrease turfgrass stress while maintaining the performance level of the putting green. Dew removal appeared to increase green speed significantly[Y=2.499-0.125.X1+0.366.X3(Y=green speed, X1=mowing height, X3=dew removal)]. Thus, dew removal is expected to maintain the green speed in the morning.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.169-173
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• 2010

Many salts have the ability to attract and remove water vapor from the surrounding environment. The ability of each salt to remove water vapor is based on the flow rate and temperature of air in surrounding. The objective of this study was toinvestigate the humid control characteristics in air-water system by using a desiccants. The aim is to asses the influence of three parameters on the humid control process which are air volume rate, air temperature and desiccant amount. Humidity control materials which consist of K (potassium) or Na (sodium) have been synthesized by the aqueous process. The humidity control properties of materials have been also investigated. Experiment results are as following. Thermal characteristics of desiccants showed similar properties regardless of processing condition. The experiments were examined by using artificial air-water system (humidity : 70~93%, air volume rate : $0.22{\sim}0.69m^3/s$). The results showed that the Na-type desiccant was an effective material. It was found that dew point increased with air volume rate, and the humidity change in humid control process was depended on desiccants amount.

• Journal of Adhesion and Interface
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• v.17 no.4
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• pp.149-154
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• 2016

In this study, natural polymer-based virus neutralizing agent was developed in an attempt to replace the conventional sterilization method for mammalian cell culture. A catechol conjugated heparin was synthesized by using EDC chemistry, and it show unique binding ability to virus which has heparin affinity (adenovirus, adeno-associated virus). To evaluate neutralization ability of catechol conjugated heparin, adeno-associated virus was used for test model, instead of using a pathogenic virus. The catechol conjugated heparin exhibited resistance to high concentration of salt and complete inactivation of adeno-associated virus. The result suggests that the catechol conjugated heparin, which is biocompatible and efficiency, may replace conventional sterilization method for mammalian cell culture.

• Journal of Korean Society of Water and Wastewater
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• v.32 no.2
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• pp.145-152
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• 2018

This study is focused on manganese (Mn(II)) removal by ozonation in surface water. Instant ozone demand for the water was 0.5 mg/L in the study. When 0.5 mg/L of Mn(II) is existed in water, the optimum ozone concentration was 1.25 mg/L with reaction time 10 minutes to meet the drinking water regulation. The ozone concentration to meet the drinking water regulation was much higher than the stoichiometric concentration. The reaction of soluble manganese removal was so fast that the reaction time does not affect the removal dramatically. When Mn(II) is existed with Fe, the removal of Mn(II) was not affected by Fe ion. However As(V) is existed as co-ion the removal of Mn(II) was decreased by 10%. Adding ozone to surface water has limited effect to remove dissolved organic matter. When ozone is used as oxidant to remove Mn(II) in the water, the existing co-ion should be evaluated to determine optimum concentration.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.180-181
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• 2007

현재 초고압 송변전기기에 적용되고 있는 $SF_6$가스는 절연 및 소호성능이 우수하며 회복특성이 뛰어나기 때문에 초고압 기기의 절연매체로서 널리 사용되고 있으나 가격이 비싸고 저온 및 높은 압력에서 액화되기 쉬우며 대기 중으로 방출될 경우에는 온실효과를 야기 시키는 단점을 가지고 있다. 최근 환경에 대한 관심과 규제가 높아지면서 온실가스에 대한 규제로서 교토 의정서가 정식 발효됨에 따라 $SF_6$가스는 금후 총량 제한에 의해 사용량이 규제 받을 가능성이 대단히 높다. 따라서 $SF_6$ 가스와 Air, N2, CO2, N2/O2 합성가스, He 등과 혼합된 절연매체들이 하나의 대안으로 연구되었다. 본 연구에서는 대체 절연가스로 주목받고 있는 Dry-air(공기 중에서 수분과 각종 불순물을 제거한 공기), N2/O2 합성가스, N2 가스를 4mm 간격의 준평등(구대구전극) 전계에서 0.5atm에서 9atm까지 변화시켰을 때 절연내력을 비교하였다. 또한, 보다 평등전계에 가까운 10mm의 간격에서도 0atm에서 4atm까지 동일한 전압을 인가하여 절연내력을 비교 분석하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.262-262
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• 2010

반도체 제조공정 중 식각공정(Etching)은 웨이퍼표면으로부터 화학적, 물리적으로 불필요한 물질들을 선택적으로 제거하는 방법이다. 식각공정 중 하나인 플라즈마 식각(Plasma etching) 공정에서 오버식각(over-etching) 과언더식각(under-etching) 되는것을피하기위해서통계적인방법을기준으로식각종료점(endpoint)를 결정한다. 본 논문의 목표는 통계적인 분석방법을 이용하지 않고 실시간 식각 데이터(realtime etching data)를 사용해서 식각 종료점을 검출하는 것이다. 식각 데이터는 시계열 데이터(time-series data)이기 때문에 간단한 구조와 적은 계산량으로 빠른 수렴속도와 좋은 안정도를 가진 Radial Basis Function Neural Network's (RBF-NN) 를 이용하여 시계열 모델(time-series model)을 구현 하였다. 광학방사분광기(Optical Emission Spectroscopy: OES)로부터 나온 6개의 데이터 세트중에서 4개의 데이터 세트는 RBF-NN을 학습하는데 사용되고 2개의 데이터 세트는 모델의 성과를 시험해 보기 위하여 사용하였다. 학습을 위한 데이터들은 Matrix화 시켜서 목표값을 설정하여 학습시킨다. 실험한 결과 학습한 RBF-NN 모형이 식각 종료점(endpoint)를 정확하게 검출된다는 것을 보여준다.

• Journal of Environmental Science International
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• v.27 no.11
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• pp.1073-1081
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• 2018

In this study, an operational data set was analysed by establishing a path model to figure out the actual cause-effect relationship of a wastewater treatment plant (WWTP); in particular, for the effluent concentrations of T-N and T-P. To develop the path models, data sets of operational records including effluent concentrations and operational factors were obtained from a field scale WWTP of $680,000m^3$ of treatment capacity. The models showed that the relationship networks with the correlation coefficients between variables for objective expressions indicated the strength of each relationship. The suggested path models were verified according to whether the analyzation results matched known theories well, but sophisticated minute theoric relationships could not be cropped out distinctly. This indicates that only a few paths with strong theoric casual relationships were represented as measured data due to the high non-linearity of the mechanism of the removal process in a biological wastewater treatment.