• Journal of Electrochemical Science and Technology
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• 제14권2호
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• pp.174-183
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• 2023

The dye wastewater discharge from the textile industries mainly affects the aquatic environment. Hence, the treatment of this wastewater is essential for a pollutant-free environment. The purpose of this research is to optimize the dye removal efficiency for process influencing independent variables such as pH, electrolysis time (ET), and current density (CD) by using Box-Behnken design (BBD) optimization and Genetic Algorithm (GA) modelling. The electrocoagulation treatment technique was used to treat the synthetically prepared Reactive Black dye solution under batch mode potentiometric operations. The percentage of error for the BBD optimization was significantly greater than for the GA modelling results. The optimum factors determined by GA modelling were CD-59.11 mA/cm², ET-24.17 minutes, and pH-8.4. At this moment, the experimental and predicted dye removal efficiencies were found to be 96.25% and 98.26%, respectively. The most and least predominant factors found by the beta coefficient were ET and pH respectively. The outcome of this research shows GA modeling is a better tool for predicting dye removal efficiencies as well as process influencing factors.

• 대한조선학회논문집
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• 제33권4호
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• pp.32-47
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• 1996

배수량형 초고속선의 선형 설계방법 및 최적치수 선정과 저항특성 추정을 위한 체계적인 이론적, 실험적 연구를 수행하였다. 본 연구에서는 먼저 최소저항이론 및 단면변화 선형식에 의한 배수량형 초고속선의 선형 설계 방법을 정립한 후 개발된 방법을 활용하여 주요 설계변수의 체계적인 변화에 따른 60척의 계열선형(series hull form)을 설계하였으며 계열선형에 대한 모형시험을 수행하여 그 결과에 대한 회귀분석을 수행하였다. 초고속선에 대한 이와 같은 체계적인 다목적 연구는 세계 최초라고 생각되며 연구 수행이 성공적으로 완료되어 준비된 전산 프로그램은 배수량형 초고속선 설계를 위한 휼륭한 도구로써 현재 극히 유용하게 활용되고 있다.

• 한국산학기술학회논문지
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• 제18권5호
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• pp.29-34
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• 2017

본 논문에서는 압연 공정을 통해 리드용 와이어를 생산할 때 생산성을 향상시키기 위해 와이어의 직진 속도를 증가시키는 방법을 연구했다. 직진 속도를 증가시킬 때 가장 중요한 점은 와이어가 원래의 목적을 바르게 수행할 수 있는 것이다. 즉, 와이어의 직진 속도가 증가함과 동시에 균열이 발생하지 않으며, 치수 공차를 만족시켜야 한다. 하지만 와이어의 직진속도를 증가시키게 되면 기존의 압하량 보다 더 큰 수치를 주어야 하고 이는 와이어에 보다 큰 손상을 주어 표면에 무리를 주게 된다. 따라서 기존의 2단계 평압연 공정을 통해 생산되었던 와이어의 필요스펙을 충족시키면서 생산성 향상까지 도모할 수 있는 3단계 평압연 공정에 관해 연구하였다. 본 연구에서는 3단계 평압연 롤러의 압하량만을 변수로 가정하고 다른 조건은 현장 조건과 일치시킨다. 상용 PIDO(Process Integration and Design Optimization) 툴인 PIANO (Process Integration, Design and Optimization)를 통해 지정한 변수 3가지를 조작하면서 실험점을 분포하고 이를 바탕으로 최적설계를 진행하여 와이어의 생산성을 향상시킴과 동시에 필요 스펙인 최대 응력의 최소화가 가능하도록 설계되었다.

• 한국공작기계학회논문집
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• 제16권6호
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• pp.146-152
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• 2007

An active micro-mixer, which was composed of an oscillating micro-stirrer in the microchannel to provide rapid, effective mixing at high flow, rates was analyzed. The effects of molecular diffusion and disturbance by the stirrer were considered with regard to two types of mixer models: the simple straight microchannel and microchannel with an oscillating stirrer. Two types of mixer models were studied by analyzing mixing behaviors such as their interaction after the stirrer. The mixing was calculated by Lattice Boltzmann methods using the D2Q9 model. In this study, the time-averaged mixing index formula was used to estimate the mixing performance of time-dependent flow. The mixing indices of the two models compared. From the results, it was found that the mixer with an oscillating stirrer was much more enhanced and stabilized. Therefore, an optimum design for a dynamic micro-mixer with an oscillating stirrer was performed using Taguchi method in order to obtain a robust solution. The design parameters were established as the frequency, the length and the angle of the stirrer and the optimal values were determined to be 2, 0.8D and ${\pm}75^{\circ}$, respectively. It was found that the mixing index of the optimal design increased 80.72% compared with that of the original design.

• 한국태양에너지학회 논문집
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• 제35권2호
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• pp.93-101
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• 2015

Zero energy building is a self sufficient building that minimizes energy consumption through passive elements such as insulation, high performance window system and installing of high efficiency HVAC system and uses renewable energy sources. The Korea Government has been strengthening the building energy efficiency standard and code for zero energy building. The building energy performance is determined by the performance of building envelope. Therefore it is important to optimize facade design such as insulation, window properties and shading, that affect the heating and cooling loads. In particular, shading devices are necessary to reduce the cooling load in summer season. Meanwhile, BIPV shading system functions as a renewable energy technology applied in solar control facade system to reduce cooling load and produce electricity simultaneously. Therefore, when installing the BIPV shading system, the length of shadings and angle that affect the electricity production must be considered. This study focused on the facade design applied with BIPV shading system for maximizing energy saving of the selected standard building. The impact of changing insulation on roof and walls, window properties and length of BIPV shading device on energy performance of the building were investigated. In conclusion, energy consumption and electricity production were analyzed based on building energy simulations using energyplus 8.1 building simulation program and jEPlus+EA optimization tool.

• 대한건축학회논문집:구조계
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• 제35권3호
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• pp.43-48
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• 2019

Since the revision of the Rationalization of Energy Use Law, the spread of new and renewable energy in buildings has been promoted. In addition, the production of electric power and thermal energy is an important issue in the change of energy paradigm centered on the use of distributed energy. Among them, geothermal energy is attracting attention as a high-performance energy-saving technology capable of coping with heating / cooling and hot water load by utilizing the constant temperature zone of the earth. However, there is a disadvantage that the initial investment cost is high as a method of calculating the capacity of a geothermal facility by calculating the maximum load. The disadvantages of these disadvantages are that the geothermal energy supply is getting stagnant and the design of the geothermal system needs to be supplemented. In this study, optimization design of geothermal system was carried out using optimization tool. As a result of the optimization, the ground heat exchanger decreased by 30.8%, the capacity of the heat pump decreased by 7.7%, and the capacity of the heat storage tank decreased by about 40%. The simulation was performed by applying the optimized value to the program and confirmed that it corresponds to the load of the building. We also confirmed that all of the constraints used in the optimization design were satisfied. The initial investment cost of the optimized geothermal system is about 18.6% lower than the initial investment cost.

• 한국전자파학회논문지
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• 제11권6호
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• pp.914-919
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• 2000

이 논문에서는 Z-밴드용 간단한 구조의 OMT (orthogonal mode transducer)가 소개되다. 이 OMT는 몇 개의 가는 유도 봉을 이용하여 한 편파를 주어진 방향으로 유도하고. 또한 다른 직각 편파를 유도 봉을 이용하여 다른 방향으로 유도하도록 설계되었다. 이 OMT는 유도 봉들이 있는 T자 형태의 도파관 부분과 두 도파관 연결부분으로 구성되어 있고, 한 안테나와 두 개의 어댑터들과 연결되도록 세 플랜지를 갖고 있다. 유도 봉의 최적개수와 최적 위치는 CAD인 HFSS를 이용하여 수치적으로 얻었다. 제작된 OMT에서 두 폄파간의 isolation은 9.5GHz와 10.5GHz 주파수 밴드에서 42.8dB보다 높았으며, 반사계수는 -17.5dB보다 낮았다. 이 OMT는 polarimetric scatterometer 시스템에 사용되는 polarimetric 안테나에 사용되어질 수 있다.

• 한국산학기술학회논문지
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• 제16권1호
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• pp.1-7
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• 2015

일반적으로 유리온실의 거터는 빗물이나 결로를 온실 밖으로 배출시키는 역할을 하는 구조물이다. 본 논문에서는 기존 거터를 개량하여 질량을 줄이고 온실의 온도차이로 발생하는 결로를 많이 담을 수 있는 새로운 거터를 설계한다. 개발할 거터는 CATIA로 설계한 후 ANSYS 구조해석과 ADAMS/Durability를 이용하여 Hot Spot해석을 수행한 결과를 바탕으로 설계하였으며, 거터의 성능을 개선하기 위해 거터의 형상, 결로의 배수, 강도 등을 고려하였다. 그리고, 개발할 거터는 설치 방법이 쉬운 결로받이 일체형 거터이며, 기존 거터보다 질량이 약 16.9% 감소하였으며 내구성도 약 10% 상향되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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• pp.417-420
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• 1990

The conventional quantitative techniques of system analysis are intrinsically unsuited for dealing with humanistic systems. Therefore, the rule based modeling of fuzzy linguistic type has been developed for the analysis of humanistic systems and complex systems and it is very significant for analysis and design of fuzzy logic controller. The activated sludge process is a commonly used method for treating sewage and waste waters. A mathematical tool to build a fuzzy model of the activated sludge process where fuzzy implications and linear reasoning are used is presented in here. A root-mean square error is used as the criterion of the fuzzy model's adequacy to the A.S.P. and the least square method is used for the identification of optimum consequence parameters. A method of modeling of the activated sludge process using its input-output data and simulation results for its application are shown.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.621-626
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• 2001

Microcellular foaming process was developed at MIT in 1980's to save a quantity of raw materials and improve mechanical properties. There are many process variables in appling microcellular foaming process to the conventional injection molding process. Of all process variables, part dimension control and shrinkage are the most influential on the post molded dimension. The post molding dimensional change of thermoplastic resins is important to tool designers for predicting the specific difference of molded part vs. actual mold cavity. Generally, articles injection molded are smaller in size than the cavity; hence, the term shrinkage factor is used to define the allowance a designer specifies. It is important to consider the factors that influence molded part dimension. According to ASTM Designation: D 955, shrinkage from mold dimensions of molded plastics was measured. In injection molding, the difference between the dimensions of the mold and of the molded article produced therein from a given material may vary according to the design and operation of the mold. In this paper, shrinkage data of molded plastic parts was obtained. It can be an important information for designing optimum mold system in a microcellular foaming injection molding process.