• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.217-217
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• 2017

Seed priming leading to improved emergences, germination speed and uniformity under unfavorable conditions without loss of longevity are the best level of techniques. We studied the possibility to obtain primed seed with reduced mean germination time (MGT) and uniformity but with simple, fast and effective methods. The experiments were carried out at $15^{\circ}C$ for 16 hours with priming treatment. To compare the effects of each treatment, we used 200mM $CaCl_2$ priming or hydro priming or no imbibition after ultrasonication or red light treatment. The light treatment was performed by irradiating 2000 lux of red light for 15, 30, 60, and 120 minutes. Addition, in order to investigate the effect of the priming solution, treated at 200mM $CaCl_2$ for 8 hours. Ultrasonication treatment was performed for 5, 10, and 20 minutes at exposures of 13.0, 17.3, and 21.6 kHz during priming. For liquid smoke (LS) treatment, seed soaked in 0%, 0.5%, 1.0%, 5.0% and 10.0% of diluted water and 200mM $CaCl_2$ solution. After each treatment, the seeds were dried to moisture content ranged 5-8% at $25^{\circ}C$ for 24 hours. The effect of seed treatment was evaluated with germination percentage (GP), MGT, germination index(GI), germination rate(GR), Germination Uniformity(GU) and heath seed percentage(HS). For several factors tested, we found that the desired germination improvement could be obtained by treating the seed with ultrasonication at 17.3 kHz for 5 minutes in water or red light exposure at 2000 lux for 120 min in water that resulted very similar to those used to 200mM $CaCl_2$ priming for 16 hrs. However, LS treatment showed no improvement in all diluted solution. Therefore, the methods applied ultrasonication and red light treatment showed high potential for fast and easy treatment avoiding pollution of salt solution waste.

• 생태와환경
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• 제34권4호통권96호
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• pp.342-348
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• 2001

본 연구는 호소내 오염된 퇴적물 처리를 위한 분리 및 농축을 위한 전처리 장치로서 hydrocyclone의 이용 가능성을 평가하는 실험이다. 외국의 선행 연구자인 Rietema의 표준 규격을 참고하여 제작된 Hydrocyclone을 이용하여 분리 및 농축 실험과 유입 및 배출 시료의 물리화학적 특성을 조사하였다. 실험결과 Hydrocyclone의 장치특성 실험에서 분리 및 농축에 가장 큰 영향요소는 몸통직경이며, 유입속도, 유입시료의 농도에 영향을 받는 것으로 조사되었다. 분리 및 농축에 필요한 한계 유입속도는 1.5 m/s로 조사되었으며, Cyclone의 몸통 직경이 작고, 유입 속도가 빠르며, 유입되는 시료의 농도가 낮을수록 분리 및 농축 효율이 높은 것으로 조사되었다. 재활용 가능성 평가를 위한 오염도 평가 결과 입자의 입경이 작을수록 오염도가 높은 것으로 조사되었으며, 분리 처리 결과 현저하게 높은 유기물 제거율을 보였다.

• 한국환경농학회지
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• 제28권1호
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• pp.38-46
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• 2009

Livestock manure is an important source of nutrients for crop production. However, farmers typically do not know the exact nutrient values for livestock manure. In many instances, manure has been viewed as a waste, and as a result it is applied close to the source resulting in over application of nutrients. Thus, the goal of nutrient application has often been applied to reduce the application expense rather than to maximize crop income. This results in wasted money and potentially negative impacts on water quality. Several livestock manure management scenarios were created based on agronomic nutrient requirements using the Utilization of Animal Manure as a Plant Nutrient (AMANURE) software to investigate water quality impacts with the National Agricultural Pesticide Risk Analysis (NAPRA) WWW modeling system. Application of manure at agronomic rates can result in high nitrate-nitrogen losses for some soil types, especially when applied in late fall. The application of manure at an agronomic rate does not necessarily equate to adequate water quality protection, and farmers must take care applying manure at agronomic rates, because nitrate-nitrogen loss potential varies spatially and temporarily. Nutrient loss probability maps for Indiana at 5%, 10%, 25%, and 50% values were created to demonstrate potential water quality impacts when livestock manure is applied to cropland at agronomic rates. The NAPRA WWW system coupled with AMANURE can be used to identify site-specific livestock manure management plans that are environmentally sound and agronomically appropriate.

• 대한방사선기술학회지:방사선기술과학
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• 제8권2호
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• pp.29-45
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• 1985

Computed Tomography Scanner (CT) is highly expensive in operation as well as purchasing. That reason may cause not only to increase the burden of patients but also to waste the capital resources leading to financial difficulties. However the numbers of CT installed throughout the country is increasing, because of efficiency in medical care, patient's concern, competitions among the hospitals within the same area. In the non-Metropolitan area the scanners were expected to be less utilized and less profitable. Nine hospitals equipped with the CT were studied on the utilization of that equipment during the period from November 1984 to February 1985 in non-Metropolitan area and break-even point in one hospital was analyzed for estimating profitabilities. The results were as follows ; 1. Among those nine hospitals, four hospitals had less than 400 beds, which is one of the restrictive minimum standards on the installation of Whole-body Computed Tomography Scanner. 2. The operating time during the normal operation period was longer than those of any other studies, but the accumulated down time was also longer than those of any other studies. The average number of scanning per week for each CT was 45, while the estimated number of for the break-even point was 56.7 cases. 3. When the downtime was excluded in calculating the average operation would be much closer to the cases for the break-even point. Therefore the break-down of the equipment was to be a main cause of the low profitability. 4. The average scanning rate for head area was 33.6%, however three of the nine hospitals showed about 20%. 5. If scanning ratio for the body parts excepting head was increased, the number of scanning for the break-even point would be diminished. 6. The small size hospital especially located near the Metropolitan area showed largest loss in the CT operation. In purchasing the highly expensive equipments in hospitals, demand should be taken into account and planning is recommended.

• 상하수도학회지
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• 제28권1호
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• pp.25-32
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• 2014

In order to investigate the effective pretreatment methods in WAS(=waste activated sludge) solubilization, the values of SCOD yield per unit SS (SCOD/gSS.hr) were compared. After the hydrodynamic cavitation with pH of 12.5, SCOD increased to 7800 mg/L, SS decreased to 45 % and the solubilization rate was 29 %. Combination of alkality (pH 12.5) and the cavitation seems to be the optimal condition for sludge solubilization. After the cavitational pretreatment, efficiencies of anaerobic digestion of the unfiltered sludge(the control), raw sludge and pretreated sludge were evaluated with BMP(=biochemical methane potential) tests. For evaluation of the biodegradability characteristics of pretreated sewage sludge, the methane production has been measured for 6 months. The methane production of pretreated sludge increased 1.4 times than that of untreated sludge. The result indicates that the cavitationally pretreated sludge was a better biodegradability substrate in anaerobic condition compared to raw sludge. It is obvious that cavitational pretreatment could enhance not only solubilization but also biodegradability of WAS. In conclusion, cavitational pretreatment of WAS to convert the particulate into soluble portion was shown to be effective in enhancing the digestibility of the WAS.

• 한국인터넷방송통신학회논문지
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• 제17권5호
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• pp.173-179
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• 2017

축산 선진국에서는 축산 폐기물을 바이오 에너지 및 퇴비, 액비로 자원화 이용하고 있다. 우리나라에서도 축산분뇨를 더 이상 페기물이 아닌 자원화 할 수 있도록 관련 연구가 활발하게 이루어지고 있다. 그러나 좁은 국토면적과 부족한 농지면적으로 가축분뇨 자원의 전량 자원화에는 어려운 상황이다. 특히 지역적으로 과잉되는 양분은 제2의 환경오염을 유발할 수 있어 지역적으로 잉여되는 양분의 관리기법이 매우 시급한 상황이다. 본 논문에서는 지역적으로 발생되는 가축분뇨 중 함유된 양분량을 정확하게 예측하기 위해서 사육단계별로 돼지 두수를 입력하면 자동으로 분뇨발생량 및 함유양분을 계산하도록 하였다. 또한 이를 통해 발생된 분뇨의 농지환원 시 시비량을 100평당 NPK 비료 3요소로 자동 계산토록 하여 시비량을 산출하는 모의실험을 수행하였다.

• 대한기계학회논문집B
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• 제21권8호
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• pp.1068-1076
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• 1997

Emission control of acid exhaust gases from coal-fired power plants and waste incinerators has become an increasing concern of both industries and regulators. Among those gaseous emissions, SO$_{2}$ has been eliminated by a Spray Drying Absorber (SDA) system, where the exhaust gas is mixed with atomized limestone-water slurry droplets and then the chemical reaction of SO$_{2}$ with alkaline components of the liquid feed forms sulfates. Liquid atomization is necessary because it maximizes the reaction efficiency by increasing the total surface area of the alkaline components. An experimental study was performed with a laboratory scale SDA to investigate whether the scrubbing efficiency for SO$_{2}$ reduction increased or not with the application of a DC electric field to the limestone-water slurry. For a selected experimental condition SO$_{2}$ concentrations exited from the reactor were measured with various applied voltages and liquid flow rates. The applied voltage varied from -10 to 10 kV by 1 kV, and the volume flow rate of slurry was set to 15, 25, 35 ml/min which were within the range of emission mode. Consequently, the SO$_{2}$ scrubbing efficiency increased with increasing the applied voltage but was independent of the polarity of the applied voltage. For the electrical and flow conditions considered a theoretical study of estimating average size and charge of the atomized droplets was carried out based on the measured current-voltage characteristics. The droplet charge to mass ratio increased and the droplet diameter decreased as the strength of the applied voltage increased.

• 유기물자원화
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• 제10권3호
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• pp.85-91
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• 2002

이 연구는 농 축 수산업으로부터 발생되는 유기성 폐기물의 재활용을 모색하여 농업적 활용방안 가능성을 조사하기 위하여 고속발효 퇴비비활를 통한 퇴비를 공시 재료로하여 그에 대한 안정성 평가와 작물에 대한 생육조사를 진단 하였다. G.I 실험에서는 상추는 모두 발아되지 않았으나 무 종자는 내엽성을 갖아 부분적으로 발아가 되었다. Shince와 TM-1이 각각 61%, 55%의 발아율을 보였고, 전체적으로 뿌리의 생장은 없었다. 퇴비의 안정성 및 비효평가는 TM-1을 제외한 모든 처리구에서, 초기에는 다소 생육이 좋았으나 생육시기가 지날수록 결과는 반대적으로 감소하였다. 따라서 퇴비의 안정성 및 비효평가는, 상추의 초기 생육은 1.5ton/10a 처리가 적당하다고 판단되며, 후기의 단계에서는 3ton/10a가 적절하다 생각된다. 그러나 지속적인 실험과 작물별 특성실험을 통하여 보다 검토가 요구된다.

• 유기물자원화
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• 제8권4호
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• pp.147-152
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• 2000

남은 음식물을 기질로 생균효모사료를 만들기 위해 Kluyveromyces marxianus 효모의 호기적 액상발효가 $35^{\circ}C$에서 시도되었다. 먼저 액상으로 시료를 충분히 마쇄시킨 시료의 효모 생균수를 증가시키기 위한 적정발효조건이 진탕배양을 통해 연구되었다. 시료로 사용된 남은 음식물의 고형분 함량을 수분첨가로 5%, 10%와 15%로 다르게 조정하여 발효시킨 결과 고형분 함량 10%에서 생균수가 가장 높은 것으로 나타났다. 효모의 생균농도를 증가시키기 위하여 Aspersillus oryzae를 2리터용 jar fermenter를 이용하여 혼합배양한 결과 증식속도를 증가시켜 주었으나 최고 생균수는 $3.5{\times}10^9/ml$로서 단독 배양시보다 근소하게 높은 결과를 보여주었다.

• 한국산학기술학회논문지
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• 제18권10호
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• pp.733-738
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• 2017

본 연구에서는 여러 사업장에서 많이 사용되는 대표적 독성 물질인 염소를 누출 물질로 선정하여 화학사고 통계자료에 따라 사고 발생 빈도가 높은 여름철 기상조건을 인자로 한 대안의 시나리오와 기존의 시행방법인 연평균 기상조건을 인자로 한 대안의 시나리오 비교분석을 통해 개선방안을 제시하고자 하였다. 2014년 1월부터 2016년 12월까지 발생한 총 296건의 화학 사고를 분석한 결과 사계절 중 여름에 가장 많은 사고가 발생하는 것으로 조사되었으며 전체 사고 발생건수의 35.81%를 차지하였다. 실제 염소를 취급하는 사업장을 대상으로 위험성 평가 결과 2016년의 경우 연평균 기상조건하에서 산출된 영향범위는 발생원으로부터 반경 712.4 m, 영향범위 내 주민 수는 20,090 명이였으며, 여름철 평균 기상조건하에서 산출된 영향범위는 발생원으로부터 반경 796.2 m, 영향범위 내 주민 수는 27,143 명으로 나타났다. 이와 같은 결과는 특정 조건하에서 현 대안의 시나리오 상의 영향범위가 포괄할 수 없는 부분이 존재함을 의미한다. 따라서 화학 물질별 특성을 고려한 Case Risk Assessment가 이루어져야 한다는 위험성 평가 제도의 발전방향을 제시한다.