• 원예과학기술지
• /
• 제19권4호
• /
• pp.471-475
• /
• 2001

난지형 마늘 재배에 있어서 시비노력 절감과 품질향상을 위한 완효성 비료의 시용효과를 구명하기 위해 실시한 실험의 결과를 요약하면 다음과 같다. 먼저 생육은 관행시비구에 비하여 완효성 비료시비구가 양호하여 초장이 4-6cm 더 길었고 엽초경이 2mm 이상 더 두꺼웠으며 엽수도 많은 경향이었다. 엽록소 함량은 월동기를 지나면서 점차 감소하다가 3월 하순 이후에 증가하였으며 생육후기인 5월에 다시 감소하는 경향을 보였으며 비종별로는 관행시비구가 추비의 영향으로 엽록소 함량이 완효성 비료 시험구보다 높은 경향을 보였다. 완효성 비료 중 CDU100처리구는 엽장이 길고 엽폭이 넓었으며 식물체 전체 중량이 무거웠다. 특히, 대구율이 관행(35.0%)보다 10.9% 높았고, 수량도 관행(1,270kg/10a)보다 5% 증수되었다. 전질소 및 피루브산 함량은 질소 무비구 및 속효성 비료 시비구에 비하여 완효성 비료 시험구에서 높은 경향을 보였다. 또한 완효성 비료 시용은 10a당 3.5시간의 시비노력이 소요되어 관행인 속효성 비료의 시비시간 4.6시간보다 24%의 시비노력 절감을 가져왔다.

• 대한인간공학회지
• /
• 제34권4호
• /
• pp.303-312
• /
• 2015

Objective: The aim of this study is to investigate the effect of insole height change in the lumbosacral angle and physical functions in healthy males. Background: In order to release male's dissatisfaction with his height and to increase satisfaction with his body, using insole is generalized. There have been researches on female's body change in accordance with function of insole and heel height, whereas there are few researches on males. Method: Participants were divided into three groups. A control group had 10 participants who wore 0cm insole. Experimental group I had 10 participants who wore 2cm insole. Experimental group II had 10 participants who wore 4cm insole. All participants wore insoles during their daily lives for a trial period of 8 weeks. The results were evaluated before and after comparison, and we measured lumbosacral angle, balance (dynamic balance, agility, quickness) and lumbar pain (LBP). Results: This study showed that insole height affected lumbosacral angle and dynamic balance and pain. In particular, there were significant differences in the 4cm group among the three groups (p<.05). The 2cm group did show a significant difference in lumbosacral angle and pain (p<.05). Furthermore, no significant difference was observed within the control group. Conclusion: The 4cm insole height suggests that the increase of lumbosacral angle contributes to some changes in LBP, balance, pain and physical functions, probably leading to negative effects on variety of activities of daily life. Application: The results of wearing insoles with proper height will help to prevent musculoskeletal disorders.

• 한국안전학회지
• /
• 제19권3호
• /
• pp.45-50
• /
• 2004

4-panel of 1m height and 45cm width were fixed on the $40cm{\times}40cm$ bottom plate and the opening of the panel comer was 5cm. Diameter of stainless vessel is loom and its height is 2cm and it located at the center of the bottom plate. 78mL liquid fuel was filled in the vessel and its depth was 1cm. Flame temperature was measured with K type thermocouple, and radiation heat of flame was measured with heat flux meter. Flame height and its behavior was visualized with video camera. and mass burning rate was measured by fuel combustion time. According to the development of fire, flame swirling was begin. From the experiment the mass burning rate was larger and the height of flame was higher than the usual pool fire flame. Flame temperature and heat flux also increased far more than the pool fire. Consequently the swirling air flow through the openings between the panel and thermal buoyance contribute to increase of heat release rate, flame length and mass burning rate.

• 한국운동역학회지
• /
• 제21권5호
• /
• pp.653-660
• /
• 2011

The purpose of this study was to compare selected kinematic variables between male medalists and a Korean male javelin thrower at the IAAF World Championships, Daegu 2011. The three medalists and one Korean javelin thrower that participated in the Championships were videotaped using three high-speed cameras (300 frames/s, EX-F1 Exilim, Casio, Japan). The results showed that the release and attitude angles of the Korean male javelin thrower (KMJT) were greater than that of the medalists, whereas the attack angle of the KMJT was smaller than that of the medalists. This study also found that the KMJT clearly had a lower release height than the medalists. As a possible adaptation of his physique to the skill, the KMJT used a small trunk inclination angle and produced greater inclination angles at his upper extremities. These results may be linked to an increase in the release angle of the KMJT. There were some difference between the KMJT and the medalists in terms of the length and duration of the delivery phase. In harmony with the shorter length of the delivery phase, its duration was shorter for the KMJT in comparison to the medalists. Because the delivery stride is considered to be a primary generator of endpoint speed, this decrease in the delivery phase time would decrease the javelin velocity at release. The amount of time taken in the delivery phase may be a critical factor to enhance a javelin thrower's performance. Thus, rhythmic movement training specifically designed for the KMJT will help him attain an optimal throwing position.

• 한국화재소방학회논문지
• /
• 제12권2호
• /
• pp.3-15
• /
• 1998

나프타분해플랜트의 부탄추출공정에서 부탄중기의 연속누출에 의한 제트화재와 플래쉬화재의 사고 결과에 대환 영향을 평가하고 사고결과에 미치는 공정변수들의 영향을 해석하였다. 877 kPa과 346.75 K의 공정조건에서 부탄중기가 87.8 kg/s의 속도로 8m의 높이에서 연속누출되 는 경우에 표준조건으로 껄정한 대기 및 환경조건에서 사고결과를 해석한 결과, 제트화재에서는 화염 의 형태와 크기를 예측할 수 있었으며 누출지점으로부터 200m에서 API모델로 산출한 복사열은 약 5 kW /m2이었고 플래쉬화재가 일어날 수 있는 연소범위는 11.2-120.2 m이었다. 그리고사고결과에 미치는조업합력의 영향은조업은도보다크며 압력이 증가할수록사고결과값이 중가하였다. 이때 플래쉬화재에서 XUFL에 미치는 공정압력의 영향은 Xr.FL에서보다 약 1/10이하를 나 타내었다.

• 터널과지하공간
• /
• 제14권4호
• /
• pp.269-274
• /
• 2004

본 연구에서는 터널에서 화재 발생시 역기류의 위치를 결정하기 위하여 축소실험을 실시하였다. Froude 상사를 사용하여 1/20로 축소된 모형터널에서 실험을 실시하였으며 가연물질로는 에탄올을 사용하였다. 한 변의 길이가 8-16cm의 화원을 사용하였으며 발열량은2.47-12.30㎾이다. 터널 단면의 종횡비(터널높이/터널폭)가 증가할수록 역기류를 제어하기 위해 더 큰 배연 풍속이 요구됨을 확인하였다. L$_{B}$$^{*}$ ＜5일 때 역기류를 막기 위한 배연속도가 0.25승에서부터 발열량에 비례하여 증가한다. L$_{B}$$^{*}$ $\geq$5에서는 발열량의 0.3승에 비례한다.

• Nuclear Engineering and Technology
• /
• 제52권4호
• /
• pp.819-826
• /
• 2020

The method of the Laplace transform has been used to obtain an analytical solution of the three-dimensional steady state advection diffusion equation for the airborne radionuclide release from any nuclear installation such as the power reactor in an area source. The present treatment takes into account the removal of the pollutants through the nuclear reaction. We assume that the pollutants are emitted as a constant rate from the area source. This physical consideration is achieved by assuming that the vertical eddy diffusivity coefficient should be a constant. The prevailing wind speed is a constant in 𝑥- direction and a linear function of the vertical height z. The present model calculations are compared with the other models and the available data of the atmospheric dispersion experiments that were carried out in the nuclear power plant of Angra dos Reis (Brazil). The results show that the present treatment performs well as the analytical dispersion model and there is a good agreement between the values computed by our model and the observed data.

• 한국응용곤충학회지
• /
• 제44권3호
• /
• pp.237-241
• /
• 2005

대용량 밀 저장 엘리베이터(직경 8 m, 높이 41 m)에서 화랑곡나방(Plodia interpunctella ($H\"{u}bner$))의 유충기생봉, Bracon hebetor Say, 방사를 통한 화랑곡나방 개체군의 억제 실험을 수행하였다. 2002 년 7월 23일부터 일주 간격으로 총 50,000 마리의 기생봉을 방사하였던 바 화랑곡나방 성충의 밀도 수준이 방사하지 않은 엘리베이터에 비해서 30% 수준으로 유지되었다.

• 한국대기환경학회지
• /
• 제14권5호
• /
• pp.397-410
• /
• 1998

Tracer experiments were performed 4 times in December 1992 on the relatively flat terrain and nearby building area adjacent to the Taedok Science Town in Korea. Each experiment was continued for relatively short period of 1 or 2 hours with intermittent release of SF6 up to 2.07g/s at 10m height. Movement of tracer plume was tracked by a continuous tracer analyzer installed on an air monitoring van. Simulation with INPUFF was carried out to analyze and predict experiments. Measured profiles of tracer plume were narrow and sharp while predicted profiles by INPUFF were broad and slowly varied. Tracer plumes were detected at a short distance of 0.5 to 2.2 km mainly due to intermittent release and high value of lower detectable limit. Various experimental conditions were tested by INPUFF simulation in order to find desirable conditions. Higher wind speed and less variable wind direction could yield longer distance of plume tracking only when the lower detectable limit was sufficiently low. Distance of plume tracking was long and did not much depend on the lower detectable limit in stable atmospheric conditions.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
• /
• pp.199-203
• /
• 2002

In this paper, the effects of water contents on combustion characteristics of paper sludge and capacity of fluidized bed combustor(FBC) were investigated using 0.26m diameter, 1.75m height pilot-plant scale combustor. Combustion tests of paper sludge containing water contents between 40wt% and 50wt% were performed. The temperature and emission variation, the pressure inside combustor were measured to monitor the fluidization quality. The experimental results showed that 30kg/hr feeding rate of sludge containing water up to 45wt% was preferable for this system. Sludge loading rate, heat release rate were calculated from experimental data as major parameters showing FBC capacity. Comparsion with sludge loading rate from other source was also performed