본 연구는 비용매 상분리법(nonsolvent induced phase separation, NIPS)을 사용하여 제조한 분리막의 배출수 처리 현장 적용성 test를 위한 최적 유효막 길이 선정 하기 위해, 동일한 원수, 기본 공정 조건으로 유효막 길이를 변화시켜 운전에 따른 역세 효율 및 운전압을 관찰하였다. 동일한 공정조건에서 유효막 길이의 변화를 주어 500㎜, 1,000㎜, 1,500㎜의 유효막 길이에 따라 1.5일간 고탁도의 가혹한 조건에서 공정을 지속하여 측정을 실시하였다. 유효막 길이별 운전 결과 유효막 길이에 따른 역세에 의한 효율차이를 확인할 수 있었으며 고탁도의 원수를 사용하여 중공사 막의 내부 폐색이 진행되었으며 유효막 길이가 길수록 폐색되지 않은 bore쪽으로만 역세가 진행되어 여과 후 역세에 의한 회복이 현저히 떨어짐을 확인하였다.

해수담수화는 지구 수자원의 97%에 해당하는 해수를 활용하기 때문에 물부족 문제를 해결할 지속가능한 대안으로 평가받고 있다. 최근에는 증발식 해수담수화 대비 에너지 소모가 낮은 분리막 방식이 널리 적용되고 있으며, 에너지 소모는 3-4 kWh/m3 정도이다. 해수담수화 플랜트 소요비용 중 운영비용이 약 35~65%를 차지하므로 해수담수화 기술의 확대 적용을 위해서는 비용 절감형 운영 기술 개발이 필수적이다. 이에 K-water에서는 ‘중동지역 맞춤형 저에너지 해수담수화플랜트 기술개발’ 과제 참여를 통해 저에너지⋅고효율 해수담수화 운영 기술을 개발하고 있으며, UAE에 구축될 1,000m3/d 규모 플랜트에 적용할 계획이다. 본 기술 적용을 통해 해수담수플랜트 연간 운영비용 증가율을 5% 이내로 유지하는 것을 목표로 한다.

In this study, high thermal efficiency and eco-friendly coffee roaster is developed. The core element of coffee roaster is a roasting drum and most of the coffee roasting drum is a flat cylindrical barrel type. From the traditional shape of cereal puffing machine, we got the idea of the roasting drum. Oak barrel shape is well known high thermal efficiency system in korean heating cook system. Therefore, we designed the coffee roaster containing the oak barrel shaped drum and combustor nozzles which has an ability of roasting 3kg of coffee beans within 10 minutes of roasting time. With our developed coffee roasting machine, the heating speed of roasting process is very fast, and the roasting of coffee beans can be quickly finished. We experimented the roasting time and compared the results with other coffee roasting machines of the same amount of roasting capacity. The results were outstanding in roasting time and the quality of roasting. In spite of smaller fuel consumption, the roasting time was more shorter than flat cylindrical roasting drum.

This study investigated phosphorus removal from secondary treated effluent using coagulation-membrane separation hybrid treatment to satisfy strict regulation in wastewater treatment. The membrane separation process was used to remove suspended phosphorus particles after coagulation/settlement. Membrane separation with 0.2 μm pore size of micro filtration membrane could reduce phosphorus concentration to 0.02 mg P/L after coagulation with 1 mg Al/L dose of polyaluminum chloride (PACl). Regardless of coagulant, the residual concentration of phosphorus decreased as the dose increased from 1.5 to 3.5 mg Al/L, while the target concentration of 0.05 mg P/L or less was achieved at 2.5 mg Al/L for the aluminum sulfate (Alum) and 3.5 mg Al/L for PACl. Moreover, alum showed better membrane flux as make bigger particles than PACl. Alum showed a 40% of flux decrease at 2.5 mg Al/L dose, while PACl indicated a 50% decrease of membrane flux even with a higher dose of 3.5 mg Al/L. Thus, alum was more effective coagulant than PACl considering phosphorus removal and membrane flux as well as its dose. Consequently, the coagulation-membrane separation hybrid treatment could be mitigate regulation on phosphorus removal as unsettleable phosphorus particles were effectively removed by membrane after coagulation.

This study was designed to investigate the carryover effects of high-forage to concentrate (F: C) diet in bred heifers on feed intake, feed efficiency (FE) and milk production of primiparous lactating Holstein cows. The experiment was conducted for 589 days (d) from onset of pregnancy through to the end of first lactation. Twenty-four bred heifers (Body weight: BW= 345.8 ± 45.4 kg and 15 ± 1.2 mon of age) randomly assigned to two groups of 3 pens containing 4 heifers each and fed high forage (HF) diet with F: C ratio of 91.7: 8.3% and low forage (LF) diet with F: C ratio of 77.8: 22.2% throughout the pregnancy period. After calving, lactating cows were fed total mixed ration (TMR) based diet. No differences (p > 0.05) were observed in dry matter intake (DMI) of bred heifers and primiparous lactating cows in both HF and LF groups. The FE of mid-to-late lactation period was higher (p< 0.05) in HF than LF group. However, the HF group showed higher (p < 0.05) milk yield, 4 % fat corrected milk (FCM) and energy corrected milk (ECM) than LF group during the 305 d lactation. The LF group showed higher (p < 0.05) milk fat, crude protein (CP), milk urea nitrogen (MUN), solid not fat (SNF) and somatic cell count (SCC) than HF group. It is concluded that restriction of F: C ratio to 91.7: 8.3% to bred heifers has the potential carryover effects to maintain higher milk yield and FE with no adverse effect on feed intake and milk composition of primiparous lactating Holstein cows.

Excessive body weight gain during the growth period of early life may predispose individuals towards obesity and metabolic disorder in later life. We investigated the possibility of using the food efficiency ratio as an early indicator for predicting susceptibility to diet-induced obesity and insulin resistance. Four-week-old, prepubertal, male Sprague Dawley rats were divided into obesity-prone and obesity-resistant groups based on food efficiency ratio values after five days on a high-fat diet. Metabolic parameters measured after 2, 6, and 10 weeks, and specific phenotypes were compared with each group. Obesityprone rats had higher increases in body weight and fat mass compared to obesity-resistant rats over the study period. Obesity-prone rats became glucose intolerant early in this study and remained so throughout the experimental period, with increases in fat weight and leptin levels occurring first, followed by increases in insulin level. Gluconeogenesis and insulin resistance significantly increased in obesity-prone groups in which activities of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase were increased and glucokinase activity decreased. Higher food efficiency ratio at an early age was closely correlated with body fat accumulation, hyperleptinemia, and hyperinsulinemia of middle and elderly age. We suggest a high food efficiency ratio in prepubertal subjects may be a useful predictor of future obesity and insulin resistance.

Cutting tools tend to wear gradually with progressing of machining process due to extremely high surface loads and temperature from the relative motions between tool and workpiece. Especially, the high cutting temperature is a dominant factor in the relation to tool life. High-pressure coolant has been reported as an effective method to prevent the severe wear from cutting temperature. This research investigates efficient supplying conditions of high-pressure coolant with the CFD results from a internal-flush drilling process. The flow rate of coolant is increased drastically up to three times under 70 bar compared to conventional way.

Entomopathogenic fungi, widely distributed in nature, have been developed as biopesticides of agricultural pests. However, little is known about isolation method for obtaining a variety of highly virulent strains from the soil. In this work, the previously established method using mealworm (larvae of Tenebrio molitor) as a baiting system was used to efficiently isolate fungal strains from soil, and the isolated fungal library in Korea was established. To isolate entomopathogenic fungi, soil samples from 10 regions of Korea such as Iksan, Imsil, Gunsan, Yeosu, Suncheon, Gwangyang, Jinju, Hamyang, Boseong and Jangseong were collected. Of the collected soils, 21 and 34 isolates of entomopathogenic fungi were isolated from Iksan and Gunsan, respectively. The isolates were classified as genera of Metarhizium, Beauveria and Isaria. This work can suggest an effective insect pathogenic fungal isolation method

무기실리카 입자로 구성된 고탁도 원수를 처리하는 침지식 정밀여과 운전에서 휴민산과 2가 양이온의 존재유무에 따라 시간에 따른 파울링 저항을 관찰하였다. 공기폭기로 인한 무기실리카 입자의 파울링 감소효과는 휴민산과 칼슘이 혼합 으로 존재 시 감소하였다. 파울링층의 전자현미경 관찰결과 칼슘의 존재 시 휴민산의 무기실리카 입자 표면흡착이 관찰되었 다. 이는 멤브레인 표면에 조밀한 파울링층을 형성시켜 공기폭기 효과를 감소시킨 것으로 판단된다. 용액의 조성에 따른 고탁 도 원수의 탁도 제거율에는 큰 변화가 없었으나 공기폭기량에 따라 칼슘과 무기실리카 입자의 혼합 존재 시 유기물질의 제거 율은 80% 이상으로 증가하였다. 이는 공기폭기 하에 무기실리카 입자 표면에 흡착된 일부 휴민산들이 멤브레인 표면으로부 터 함께 역수송 되어 유기물질 제거율을 증가시킨 것으로 사료된다.

Modified coagulants were investigated for the removal of phosphorus from secondary effluent of wastewater treatment. The modified coagulants were prepared by mixing alkali earth metal ions such as calcium and magnesium. The basicity of a coagulant influenced on the removal of phosphorus, and coagulants with basicity of 5.9% showed a better removal of total phosphorus than that of 38.5%. Also, coagulants with alkali earth metals enhanced the performance of coagulation by 10% and resulted in 67.1% for total phosphorus removal. Moreover, the removal of suspended solids and chemical oxygen demand was improved using coagulants with low basicity and earth metal ions. Results of this study demonstrated that the use of coagulants with low basicity, and calcium and magnesium ions is recommended to improve wastewater effluent quality.

This study was conducted to investigate the fishing efficiency of an improved LED fishing lamp for squids. A total of 31 fishing operations were carried out with six-crew commercial fishing vessel Haengbok-Ho (24 tons) on which 43.2kWLED was installed, along with 14 automatic jigging machines, from October 6 to November 16, 2012. The 19 fishing vessels with Haengbok-Ho were compared with a control subject was 24 tons or 29 tons. A total illuminating power ofmetal halide (MH) fishing lamps in the control fishing vessel was either 84kW or 120kW. The number of automatic jigging machines in the control vessels was 8-18 and the number of crews engaged for fishing operation was 3-13. Average fuel consumption of LED fishing vessels during fishing operation was 505.1l which led to an average fuel consumption of 42.7l per hour. LED fishing vessel andMH fishing vessel caught on an average 1,946 squids and 2,439 squids, respectively, during the study period. Crews (hand line and hand reel) caught about 2.2 times the automatic jiggingmachines for LED fishing vessel and about 2.1 times forMH fishing vessel. Meanwhile, catches by the fishing vessels with LED in the combined total number per one line of automatic jigging machine and per crew were 86.6% of that of the control fishing vessel with MH. Also, fishing vessels with LED per automatic jigging machine achieved 71.8% of catches of that with MH fishing lamp. The catches of squids per the fishing vessel with 1W LED fishing lamp were higher by more than 135.5% of that in the fishing vessel with MH, which showed a good fishing performance even with only the use of a LED fishing lamp.

Electro-accel pedal is needed to raise fuel efficiency by controlled pedal angle signal regardless driver’s willings to fast start or stop pedaling, and to reduce muscle fatigue by designed Ergonomic structure. For this purpose, in this study, we designed new mechanism of accel pedal in a double linkage with two springs to minimize the force of pedaling on main pedal period for HECV in close the future. We have achieved the simulation to dynamic characteristics and experimented to measure the pedal force with proto sample, and confirmed the potentialities this new mechanism.

This paper describes study of the converter topologies for a low-cost, high-efficiency switched reluctance motor(hereafter abbreviated as SRM) drive. The considered converter employs two-switch split AC supply configuration. The converter preserves a single switch per phase as well as a single phase-leg rectifier circuit realizing the fewest component count to achieve a highly cost effective solution for two-phase SRM drive. Comparative study between the considered converter and other converters are provided. Analysis of the modes of operation and mathematical modeling are also provided. Analysis and simulation results are provided to validate the converter. The considered split AC converter can be a strong candidate for low-cost applications such as power tools, fans, and small appliances where both cost and efficiency are most valued.

This study is concerned about the optimal design of the base in a vibrating screen. Vibrating screen is widely used for grading and screening materials in the fields such as coal-selecting, mining-selecting, building materials, electrical power and chemical industry, etc. It is composed of base, frame, vibrator, screen, spring, trough, clamp and etc. Especially, base in vibrating screen are stressed by high, mostly shock-type loads. Nevertheless, design of base is dependent on experience, and it will cause reliability reduction and cost increase. The base is composed by the lower plate, the middle plate and the upper plate. This research purpose is to propose and verify a method to achieve higher product quality, lower costs, and far less physical testing. In this study, design parameters used for optimization are the lower plate thickness(7mm, 9mm, 11mm), the middle plate thickness(4mm, 4.5mm, 5mm) and the upper plate thickness(7mm, 9mm, 11mm) in the base. The result showed that base weight reduced to maximum 19.1% when compared with the current vibrating screen.

In this study, mold does not modify the overall. And core was developed as part of a separate. And not detached from the injection mold core part of the device only has to exchange. It has to perform the simulation of resin flow injection. Result of analysis, problems were observed. To create the change core of the four kinds of production prototypes and replace only with the exchange of change core operation of the injection. As a result, there were able to get a products with smooth surface.

We have fabricated and evaluated newNew high high-efficiency green green-light light-emitting phosphorescent devices with an emission layer of [TCTA/TCTA1/3TAZ2/3/TAZ] : Ir(ppy)3 were fabricated and evaluated, and compared the electroluminescence characteristics of these devices were compared with the conventional phosphorescent devices with emission layers of (TCTA1/3TAZ2/3) : Ir(ppy)3 and (TCTA/TAZ) : Ir(ppy)3. The current density, luminance, and current efficiency of the a device with an emission layer of (80Å-TCTA/90˚Å-TCTA1/3TAZ2/3/130Å-TAZ) : 10%-Ir(ppy)3 were 95 mA/cm2, 25000 cd/m2, and 27 cd/A at an applied voltage of 10 V, respectively. The maximum current efficiency was 52 cd/A under the a luminance value of 400 cd/m2. The peak wavelength and FWHM (FWHM (full width at half maximum) in the electroluminescence spectral were 513 nm and 65 nm, respectively. The color coordinate was (0.30, 0.62) on the CIE (Commission Internationale de I'Eclairage) chart. Under the a luminance of 15000 cd/m2, the current efficiency of the a device with an emission layer of (80Å-TCTA/90Å-TCTA1/3TAZ2/3/130Å-TAZ) : 10%-Ir(ppy)3 was 34 cd/A, which has beenshowed an improvement of improved 1.7 and 1.4 times compared to those of the devices with emission layers of (300Å-TCTA1/3TAZ2/3) : 10%-Ir(ppy)3 and (100Å-TCTA/200Å-TAZ) : 10%-Ir(ppy)3, respectively.