This paper aims to study the modeling and controller of an electrically driven tractor optimized for energy efficiency under off-road conditions and when subjected to loads such as plowing. The dynamic model design is aimed at a 30kW electric tractor. The vehicle model consists of a 30kW motor, transmission, wheels, and a controller, designed using the commercial software Matlab/Simulink. In order to optimize energy efficiency under load conditions, this paper designs and implements a PID controller focusing on the vehicle's speed and wheel slip. The newly proposed electric tractor modeling and PID controller aim to demonstrate improved energy efficiency through simulation.

Considering the characteristics of aldehydes among volatile organic compounds, a combined process was established by linking an absorbent and a photocatalytic reactor. Experiments to find the optimal operating conditions of the combined process showed that as the amount of photocatalyst coating increases, the wavelength of the ultraviolet lamp used becomes shorter, the photodegradation rate becomes faster, and the removal efficiency increases. It was also demonstrated that by controlling the relative humidity during the connection process of the combined process, the re-evaporation phenomenon at the front end (absorption area) of the hybrid process can be improved and the removal efficiency at the back end (photocatalytic reaction area) can be significantly enhanced. This confirmed the need for a combined process that complements the advantages and disadvantages of each process.

The fuel efficiency was 16.77km/L on average for D-ENG and 12.97 km/L for B-ENG. The fuel efficiency of D-ENG was 22.66% higher than that of B-ENG. NOX had an average D-ENG of 191.75ppm and B-ENG of 104ppm. NOX of D-ENG occurred 145.76% more than B-ENG. The amount of CO2 generated was 154.25ppm for D-ENG and 199ppm for B-ENG. CO2 of D-ENG occurred 29.01% less than B-ENG. From this, it was found that the higher the fuel efficiency, the higher the emission of nitrogen oxide and the lower the emission of carbon dioxide decreased.

환경친화적 생물적방제를 위해 수출딸기온실에서 해충인 점박이응애 밀도 감소 효율을 화학적방제와 생물적방제로 나누어 동일한 크기의 동일한 온실에서 각각 비교하였다. 생물적방제 온실은 점박이응애의 천적인 칠레이리응 애만을 이용하였고, 화학적방제 온실은 일반 화학합성 농약을 이용하여 점박이응애의 밀도를 조절하였다. 화학적방제 온실에 비해 생물적방제 온실에서 점박이응애 모든 태의 밀도가 낮게 관찰되었으며, 생물적방제를 위한 비용이 화학적방제에 비해 낮았다. 이러한 결과는 수출딸기의 주요해충인 점박이응애의 방제에 칠레이리응애를 이용한 생물적방제가 가능한 것을 나타내고 있다.

드론은 현재 산업의 각 분야에서 사용되고 있으며, 농업분야에서도 활발히 사용되고 있다. 특히, 초고 령 사회에 진입한 농촌과 농업분야에서 드론은 매우 효율적인 방제장비로 각광받고 있다. 드론방제기 는 운용비용이 다른 방제기에 비해서 매우 낮으며 구입비용 또한 그리 높지 않다. 한 단위의 방제면적 을 방제하기 위하여 투입되는 구입비용과 운용비용을 모두 고려하였을 때 가장 효율적인 방제기는 고 정익방제기와 드론이라 불리는 멀티콥터형 방제기이다. 고정익방제기에 소요되는 높은 운용비용과 탑 승조종사의 인건비를 고려한다면 우리나라에서 현실적으로 효율적인 방제기라 볼 수 없으며, 조종사가 탑승하지 않는 드론방제기가 매우 효율적인 방제기라고 할 수 있다. 현재 농업분야에서 방제작업에 활 발히 쓰이고 있는 드론방제기는 높은 비용효율성으로 인하여 많은 농민들에게 선호되는 방제기로 선택 되고 있다.

We developed a wet scrubber by applying cyclone flow to the gas flow and using a spiral filter structure. While the size of a new scrubber was about half that of a conventional scrubber, the device showed relatively high efficiency in pollutants removal such as particulate matter and compounds inducing odor. The new scrubber installed in a plating industry showed a higher removal efficiency of about 5% for dust, about 23% for hydrogen chloride, and about 23% for sulfur dioxide compared to the conventional scrubber. Plurality of tubes in the spiral filer housing are arranged to be vertically shifted from each other. Because the upward residual gas does not directly rise vertically, the residence time of gas between the filter plates is extended. Thus, the purification efficiency of the pollutants was enhanced in the new scrubber. In addition, the new scrubber developed in this study is more cost effective because the cost saving in manufacturing it compared with a conventional scrubber increases with increasing the size of equipment. It is expected that a scrubber with better dust collecting efficiency can be obtained by carrying out a study in connection with facilities capable of controlling acidity of washing water.

저농도 합성폐수를 처리하는 membrane bioreactor (MBR) 시스템에서 공기폭기와 PET (polyethertaraphtalate) 입상메디아 혼합사용이 멤브레인 파울링과 처리효율에 미치는 영향을 관찰하였다. 일정한 공기폭기유량과 투과플럭스로 실험한 결과, PET 메디아를 첨가 시 메디아를 첨가하지 않은 경우보다 낮은 파울링 속도가 관찰되었다. MBR 반응기에서 입상 메디아에 의한 파울링 감소효과는 중공사막 모듈에 비해 평막 모듈이 더욱 효과적이었다. 공기폭기와 함께 멤브레인 표면을 따라 움직이는 입상 메디아의 접근성과 접촉성이 중공사막보다 효과적이었던 것으로 사료된다. MBR 적용에 있어 PET 메디아의 적용은 메디아를 적용하지 않았을 때와 비교 시 MBR 처리효율에 큰 영향을 주지 않았다.

The jet production efficiency of radio galaxies can be quantified by comparison of their kinetic jet powers Pjet and Bondi accretion powers PB. These two parameters are known to be related linearly, with the jet power resulting from the Bondi power by multiplication with an efficiency factor of order 1%. Using a recently published (Nemmen & Tchekhovskoy 2014) high-quality sample of 27 radio galaxies, I construct a PB − Pjet diagram that includes information on optical AGN types as far as available. This diagram indicates that the jet production efficiency is a function of AGN type: Seyfert 2 galaxies seem to be systematically (with a false alarm probability of 4.3 × 10−4) less efficient, by about one order of magnitude, in powering jets than Seyfert 1 galaxies, LINERs, or the remaining radio galaxies. This suggests an evolutionary sequence from Sy 2s to Sy 1s and LINERs, controlled by an interplay of jets on the one hand and dust and gas in galactic nuclei on the other hand. When taking this effect into account, the PB − Pjet relation is probably much tighter intrinsically than currently assumed.

Strawberry, Fragaria ananassa Duchesne, is one of the important horticultural crops cultivated in greenhouses. Tetranychus urticae is one of major strawberry pests, and Neoseiulus californicus and Phytoseiulus persimilis have been used as biological control agents for control of T. urticae. The interactions between T. urticae and N. californicus and between T. urticae and P. persimilis were investigated to compare their control efficiency for T. urticae on a spatially-structured strawberry leaf disc area at different temperatures and on different treatments. The experimental arena was an array of leaf discs (3 cm diameter) placed upside down on a water-saturated cotton pad in an aluminum pan (17.4 x 21.5 cm). Twenty leaf discs (4 x 5) were placed adjacent each other for allowing dispersal of T. urticae and its predatory mites. The temperature conditions were 20, 25, and 30°C and there were six different treatments. The overall population densities of T. urticae were influenced by temperature (20, 25, and 30°C) in N. californicus treatment. In the same temperature condition, P.persimilis was more effective than N. californicus to control T. uritcae. Two predator systems were better than one predator systems to suppress the population density of T. urticae at 25°C. Some results of this study could be used to understand the spatial association of T. urticae and its predatory mites in greenhouse crops and fields.

이전 실험에서 결정된 생육 단계별 최적 환경조건을 평가하기 위한 4가지 처리는 다음과 같았다: 생육 단계별 최적 환경 조건을 사용한 광독립 영양배양(photoautotrophic optimum condition with growth stage (POG)), 생육 단계별 평균 광합성 광량자속 밀도(photosynthetic photon flux density(PPFD))와 CO2 농도를 사용한 광독립 영양배양(photoautotrophic constant condition with average PPFD and CO2 of POG(PCA)), 생육 단계별 최대 PPFD와 CO2농도를 사용한 광독립 영양배양(photoautotrophic constant condition with maximum PPFD and CO2 of POG(PCM)) 그리고 대조군으로 3%의 당을 포함한 광혼합 영양배양(photomixotrophic conventional condition with 3% sucrose(PMC)). 실험 결과 각 생육 단계별 환경제어(POG)는 기내에서 배양된 감자 소식물체의 모든 생육 관련 항목에서 유의적 증진을 유도하였다. 또한 단위 건물중 당 소비된 전력과 CO2는 모든 처리 중 POG에서 가장 낮았다. 기외 이식 이후에도 POG에서 생산된 감자 묘는 PMC에서 자란 감자 묘와 전체적으로 큰 차이 없이 왕성한 생육을 유지하였다. 특히 POC는 기존 광혼합 영양방식(PCM)과 비교했을 때 기외 이식전과 이식 후 20일째 각각 4.7배와 3.8배 높은 건물중을 기록하였다. 따라서 POG와 같은 생육 단계별 환경 조절을 통한 광독립 영양 미세 증식 방법은 에너지 절감 효과와 함께 무균의 건강한 감자 묘의 생산에 효과적이었다.

본 논문에서는 ABR(Available Bit Rate) 트래픽의 흐름제어를 방식들을 분석하고, 지연이 큰 PNNI망에서 VS/VD 스위치를 이용하여 효율적으로 ABR 트래픽을 제어하여, 공평한 전송율을 계산할 수 있는 알고리즘을 제안하였다. 제안된 알고리즘에서는 전송률을 계산하기 위하여 정확하고 공평한 분배를 계산할 수 있는 ER(Explicit Rate) 방식의 FMMRA(Fast Max-Min Rate Allocation)를 사용하였다. 그리고, 지연이 많이 된 상태에서도 큐에 있는 셀을 서비스하고 드레인하기 위하여, VD에서 VS로 전달된 큐 길이 정보를 이용하여 전송율을 계산함으로서 공평한 셀 서비스 분배를 할 수 있었다. 컴퓨터 시뮬레이션을 통하여 제안된 알고리즘의 성능을 평가하였으며, 그 결과 만족할 만한 성능을 얻을 수 있었다.

We have improved the control and driving system of 16' reflector at Kwanak Observatory at Seoul National University, by completing encoder unit, and by developing programs for correction of errors resulting from hardware defects. The hardware defects of this telescope system are the large backlash and the nonuniform tracking and pointing. The telescope pointing accuracy for RA is improved to a few arc minutes, and that for DEC is several tens of arc minutes. The guiding error is improved to 0.7 arcsec/minute, allowing up to 3 minutes exposure for CCD imaging under typical seeing conditions at the Observatory.

As the Photovoltaic system market increases, various technologies are emerging to improve system operation efficiency. Such additional systems of the power generation system are generally referred to as ‘Balance of System’, for example a panel cooling, a panel cleaning and a panel angle adjusting apparatus. In this paper, we discuss an algorithm to calculate the target temperature of cooling in response to changes in the installation environment conditions of the power generation system so that the efficiency improvement rate target set by the user can be achieved with respect to the control method of the cooling water injection system among various panel cooling apparatuses. In order to calculate the target temperature of cooling, the output enhancement coefficient is calculated experimentally based on the temperature change according to the solar radiation condition of the PV panel, and the required reduction temperature of each irradiation condition is calculated considering the efficiency improvement rate. In addition, the efficiency improvement ratio is calculated considering the installation condition of the general power generation system without a separate control group. The thermal performance coefficient of the PV panel test body for calculating the expected temperature of the PV panel is calculated experimentally. The target temperature of cooling is calculated as the sum of the expected temperature of the PV panel and the required reduction temperature, and the injection system that tracks the target temperature by cooling water injection is constructed and compared with the power generation improvement rate and the user setting efficiency improvement rate.

In general, since partial pollen is derived to sporophyte, anther culture efficiency is low, and practical application that is introduced in actuality breeding technology is not many. This study was carried out to improve regeneration of green plants through some culture environments contol in anther culture of naked brley. Among the factors related with plant regeneration, medium was effective in component containing L-glutamine 256 mg/L, L-proline 250 mg/L, IAA 1 mg/L and BAP 2 mg/L controlled in addition sucrose 30 g/L or maltose and sucrose mixed each 30 g/L to increase both plant regeneration and green plant regeneration rate. Also, adequate content of CuSO4 was the best at 1.25 mg/L (fifty-fold), it was tendency to decrease albino production rate. Starvation was effective at 30℃, 7 days in case of Saessalbori for plant regeneration and Dooweonchapssalbori at 30℃, 10 days with increasing green plant regeneration against albino. After plant regeneration, under acclimation by hydroponics, roots and shoots were well developed at 20℃, light control as 2,000～5,000 Lux and photoperiodic reaction by 14/10 as dark/light in the early growth stage. In acclimation method, plants acclimated in the modified Yoshida solution filled-vermiculite in GP pot is superior (100%), in which was controlled by temperature 20℃, pH 6.0 and relative humid 90% over, especially, after transplanting in pot growth of root, sheath and leaf are more active in 20℃ and 5,000 Lux control. For Vernalization, plants derived from anther culture of F1 naked barley was different from their parents with normal heading plant even about 50% in the F1 hybrids whose vernalization was strong, whereas the rest of plants derived from anther culture formed rosette, showing that normal growth were impossible.