To overcome recent emission regulation, various hybrid systems are being developed. In the E-4WD(electric four wheel drive) system, the engine and transmission drive the front wheel, electric motor and single reduction gear drive the rear wheel. As the gear ratio of the reduction gear set determines the electric motor's operating point, the gear ratio is important to enhancement efficiency of hybrid system. This study is to analyze motor reduction gear ratio's influence on E-4WD hybrid system for optimized efficiency and driving performance. Fuel economy, operating point of power source and hybrid mode are analyzed using simulation developed with dynamic programming method.

The limitations and problems of the rechargeable battery and short mileage per one electric charging have not been overcome at the electric vehicles. To solve these problems, the hybrid vehicle has been developed by securing the performance of automotive with the conventional internal combustion engine and the environmental benefit. Meanwhile, the electric UTV (utility terrain vehicle) which has this environmental benefit has been widely used for factories, parks, leisure and agricultural areas. In this study, the electric UTV was fabricated and attached the auxiliary power drive systems including the photovoltaic power generation system into this electric vehicle in order to make up the hybrid (motor + photovoltaic) vehicle system. As the range of the hybrid UTV would be extended over 20% than that of the existing golf cart per one electric charging through this successful development, the dynamic stiffness was improved through light-weight body design.

Seawater desalination market after global economic crisis has been stalled due to the market uncertainties and decreased demand in desalination. It is important to review the status of the market and to estimate the appropriate share of Forward osmosis-Reverse Osmosis (FO-RO) hybrid desalination technology by figuring out the outlook of the desalination market. Main part of the desalination market will still be MENA (Middle East and North Africa) in the near future due to the fast population increase and high dependency of fossil fuel in the region. The market for FO-RO hybrid technology, however, might be smaller than the conventional SWRO desalination market anyway because of aesthetic issues from using wastewater as raw water and higher costs associated with capex. Therefore, it is essential to improve FO membrane performance and system operation technologies in order to make the hybrid technology attractive compared to the conventional SWRO technology.

By development with a one-piece support ring containing the hybrid vehicle in this study by cooling to obtain the following findings. First, we analyze foreign hybrid vehicle SUPPORT RING product. Second, the design and development targets SUPPORT RING optimum shape. Third, Prototype FCD500 appearance (wooden) cores and tries to mold design and production. Fourth, the manufacturing technology developed cores of high rigidity, low-expansion unit for the formation channel. Fifth, the development of the casting process technology to remove the channel buttress part shrinkage defects and bubbling. Sixth, to produce a casting SUPPORT RING FCD500 with cooling channels. Seventh, SUPPORT RING performs the CAE analysis for Prototype Casting casting mold development. Evaluate the eighth SUPPORT RING FCD500 casting with cooling channels. Ninth, cooling channels parts Pneumatic 2bar. And securing the confidentiality satisfying 0.5cc / min. Finally, a review of the assembly performance of the prototype.

FRP Hybrid Bar, composite structures composed of synthetic resins, deformed bar and glass fiber, was invented in order to solve corrosion of rebar in reinforced concrete structures. In order to bond deformed bar and glass fiber to FRP Hybrid Bar, synthetic resins is used. Curing time of the synthetic resins greatly affect productivity. If curing time of synthetic resins is short, cost of facilities is reduced and productivity is increased. Also, If this curing time is shorter or omitted, FRP Hybrid Bar can be commercialized. So, it can cause mass-production and substantial economic effect. Therefore, in this paper, optimum mix proportion is observed in order to increase economic efficiency of FRP Hybrid Bar and reduce curing time of synthetic resins. Total 9 variables are set, adjusting ratio of hardener ratio, and 3 resin moulds on each variables are fabricated. Optimum mix proportion is suggested based on data measured by temperature sensor.

본 연구에서는 풍하중을 받는 건물에 설치된 다중거동 복합 감쇠장치(MHD)의 성능을 평가하고, MHD 예비설계 절차를 제안하였다. MHD에 의해 증가된 등가감쇠비와 그에 따른 건축구조기준에 근거한 응답저감계수를 예상한 후, 풍하중 스펙트럼에 의해 생성된 풍하중을 사용하여 20층 철골구조물에 대한 시간이력 해석을 수행하였다. 해석결과를 통해 얻어진 층변위 및 층간변위 평균 응답 감소율은 각각 0.585 및 0.525로, 이는 제안한 예비설계과정에서 추정된 응답감소계수 0.6과 거의 동일한 수치임을 확인하였다. 이로부터 제안된 방법을 사용하여 MHD의 제어효과를 효과적으로 평가할 수 있음을 확인하였다.

The proposed hybrid damper installs at a coupling beam and consists of a high-damping rubber (HDR) and steel pin. The proposed hybrid damper adopted a pin-lock system acts as a viscoelastic damper under wind load (small displacement) while it behaves as a hysteretic damper under earthquake load (large displacement). In this paper, the pin-lock mechanism and structural performance of the proposed hybrid damper is evaluated through experiment. Experiments were carried out with the variables which displacement, loading frequency and steel pin quantities were used. Test results showed that the pin-lock mechanism and the performance of the hybrid damper under a large displacement were verified. Also equivalent damping ratios of HDR were increasing at a small displacement as displacement amplitudes were increasing. However HDR did not depend on frequency,

Gas hydrate desalination process is based on a liquid to solid (Gas Hydrate, GH) phase change followed by a physical process to separate the GH from the remaining salty water. The GH based desalination process show 60.5-90% of salt rejection, post treatment like reverse osmosis (RO) process is needed to finally meet the product water quality. In this study, the energy consumption of the GH and RO hybrid system was investigated. The energy consumption of the GH process is based on the cooling and heating of seawater and the heat of GH formation reaction while RO energy consumption is calculated using the product of pressure and flow rate of high pressure pumps used in the process. The relation between minimum energy consumption of RO process and RO recovery depending on GH salt rejection, and (2) energy consumption of electric based GH process can be calculated from the simulation. As a result, energy consumption of GH-RO hybrid system and conventional seawater RO process (with/without enregy recovery device) is compared. Since the energy consumption of GH process is too high, other solution used seawater heat and heat exchanger instead of electric energy is suggested.

Desalination is getting more attention as an alternative to solve a global water shortage problem in the future. Especially, a desalination technology is being expected as a new growth engine of Korea’s overseas plant business besides one of the solutions of domestic water shortage problem. In the past, a thermal evaporation technology was a predominant method in desalination market, but more than 75% of the current market is hold by a membrane-based reverse osmosis technology because of its lower energy consumption rate for desalination. In the future, it is expected to have more energy efficient desalination process. Accordingly, various processes are being developed to further enhance the desalination energy efficiency. One of the promising technologies is a desalination process combined with Pressure Retarded Osmosis (PRO) process. The PRO technology is able to generate energy by using osmotic pressure of seawater or desalination brine. And the other benefits are that it has no emission of CO2 and the limited impact of external environmental factors. However, it is not commercialized yet because a high-performance PRO membrane and module, and a PRO system optimization technology is not sufficiently developed. In this paper, the recent research direction and progress of the SWRO-PRO hybrid desalination was discussed regarding a PRO membrane and module, an energy recovery system, pre-treatment and system optimization technologies, and so on.

본 연구에서는 알루미나 정밀여과 및 광촉매 코팅 폴리프로필렌의 혼성 수처리 공정에서 물역세척 시간 (back-flushing time, BT) 및 PP 구 변화의 영향을 알아보고, 알루미나 한외여과막와 동일한 PP 비드를 사용한 선행 결과와 비 교하였다. 물역세척 주기(FT)는 10분으로 고정한 채, BT를 6~30초로 변화시키면서, 그 영향을 180분 운전 후 막 오염에 의한 저항(Rf), 투과선속(J)과 총여과부피(VT) 측면에서 고찰하였다. BT가 길어질수록 Rf는 급격히 감소하고 J는 증가하였으나, VT는 BT 10초일 때 최대였다. 탁도의 처리효율은 99.0% 이상으로 BT의 영향이 보이지 않았다. 한편, 유기물 처리효율은 역세척 없 는 조건(NBF)에서 89.0%로 가장 높았으며, BT가 길어질수록 증가하였다. 막오염 측면에서 최적 PP 비드의 투입 농도는 20 g/L이었으나, 알루미나 한외여과막와 동일한 PP 비드를 사용한 선행 결과 최적 PP 비드의 농도는 40 g/L이었다. 탁도와 유기 물 처리효율은 PP 농도 30 g/L에서 최대였으나, 선행 결과 탁도와 유기물 처리효율은 모두 PP 농도 40 g/L에서 가장 높았다.

The main objective of this paper is to develop computer simulation program for performance evaluation and cost estimation of a reverse osmosis (RO) and pressure-retarded osmosis (PRO) hybrid process to propose guidelines for its economic competitiveness use in the field. A solution-diffusion model modified with film theory and a simple cost model was applied to the simulation program. Using the simulation program, the effects of various factors, including the Operating conditions, membrane properties, and cost parameters on the RO and RO-PRO hybrid process performance and cost were examined. The simulation results showed that the RO-PRO hybrid process can be economically competitive with the RO process when electricity cost is more than 0.2 $/kWh, the PRO membrane cost is same as RO membrane cost, the power density is more than 8 W/m2 and PRO recovery is same as 1/(1-RO recovery).

When a single inorganic precursor is used for the synthesis of a sol-gel coating, there is a problem of cracking on the surface of coating layer. In order to solve this problem of surface cracking, we synthesized inorganic-organic coatings that have hybrid properties of inorganic and organic materials. Sols of various ratios (1:0.07, 0.2, 0.41, 0.82, 1.64, 3.26, 6.54, 13.2) of an inorganic precursor of Tetrabutylorthotitanate (Ti(OBu)4, TBOT) and an organic precursor of γ-Methacryloxy propyltrimethoxysilane (MAPTS) were prepared and coated on stainless steels (SUS316L) by dip coating method. The binding structure and the physical properties of the synthesized coatings were analyzed by FT-IR, FE-SEM, FIB (Focused Ion Beam), and a nano-indenter. Dynamic polarization testing and EIS (electrical impedance spectroscopy) were carried out to evaluate the micro-defects and the corrosion properties of the coatings. The prepared coatings show hybrid properties of inorganic oxides and organic materials. Crack free coatings were prepared when the MAPTS ratio was above a critical value. As the MAPTS ratio increased, the thickness and the corrosion resistance increased, and the hardness decreased.

탄소나노튜브(MWCNT)를 고분자에 첨가하게 되면 그 물성을 향상시킬 수 있다. 기존의 연구 결과에서 PEO 막에 EVA 를 첨가함으로써 막의 기체투과도와 선택도의 향상을 확인하였다. 본 연구에서는 탄소나노튜브의 분산을 위하여 산처리 과정을 통해 표면에 카르복실기를 도입한 탄소나노튜브(MWCNTCOOH) 를 제조하여 PEO/EVA/MWCNT 혼성막을 제조하였다. 제조된 막의 특성은 TGA, SEM 분석으로 확인하였으며 막의 CO2, O2, N2 기체에 대한 투과도와 선택도 또한 확인하였다.