• 한국물환경학회지
• /
• 제22권5호
• /
• pp.913-918
• /
• 2006

Both raw wastewater and effluent from a rubber products manufacturing factory were found to be toxic to Daphnia magna though the effluent satisfied current water quality standards. Thus, in order to reduce toxicity, advanced oxidation processes (AOPs) such as gamma-ray (${\gamma}-ray$) treatment and ozonation ($O_3$) were applied. A combined ${\gamma}-rays/O_3$ treatment at 20 kGy after coagulation significantly reduced toxicity of raw wastewater, changing 48-h toxic unit (TU) value from 201.21 to 23.92. However, toxicity of treated water was higher than that of effluent (TU = 12.15). This shows limitation of gamma-ray treatment to remove toxicity of raw wastewater. In case of effluent, the combined ${\gamma}-rays/O_3$ treatment at 20 kGy efficiently decomposed toxic compounds down to non toxic level. This work strongly supports the necessity of toxicity reduction evaluation as well as toxicity-based effluent management.

• 한국식품영양과학회지
• /
• 제40권9호
• /
• pp.1292-1299
• /
• 2011

본 연구는 우리의 전통발효식품인 고추장을 제조할 때 품질향상을 부여하기 위한 방법으로 영양성 및 기능성이 풍부하다 알려진 작두콩으로 제조한 청국장 분말을 메주 대신 사용하여 제조한 고추장의 품질 특성 변화를 조사한 결과는 다음과 같다. 작두콩청국장분말(SBC)의 첨가비율을 달리한 SBC 2, 5, 8 및 10%의 숙성기간 중 수분함량 변화는 대조고추장(SBC 0)과 비교하여 차이가 없었다. SBC 2, 5, 8 및 10의 담금 초기 염도는 SBC 첨가량에 따른 변화가 없었고, 90일 숙성 후 염도도 숙성전후의 SBC 0과 차이가 없었다. 환원당 함량은 SBC 첨가비율이 높을수록 증가하였다. 색도는 SBC 첨가에 따른 큰 차이가 없었다. 90일 숙성된 고추장의 미생물상은 호기성 세균의 경우 $5.42{\times}10^7{\sim}9.59{\times}10^7$ CFU/g 수준이었고, 효모의 경우 $1.14{\times}10^2{\sim}9.73{\times}10^2$ CFU/g이었다. 작두콩청국장 첨가 고추장과 대조고추장에서 검출된 Bacillus cereus 식중독 균은 $8.49{\times}10^2{\sim}1.25{\times}10^3$ CFU/g 수준으로 비슷하거나 약간 낮은 수준이었다. 90일 숙성된 고추장의 관능평가 결과 종합적 기호도는 6.95로 SBC 10이가장 우수하였다. 이상의 결과를 보아 작두콩청국장분말을 첨가한 고추장의 품질은 일반메주로 제조한 고추장과 비교하여 큰 차이가 없고, 관능적으로 SBC 10의 품질이 SBC 0보다 우수함을 알 수 있었다.

• 생명과학회지
• /
• 제29권5호
• /
• pp.580-587
• /
• 2019

저서성대형무척추동물은 수질 평가를 위해 다년간 이용되었다. 본 연구는 한국 송지천에서 저서성대형무척추동물을 이용하여 이 하천의 수질을 평가하고자 수행되었다. 동정된 동물은 3문 5강 12목 18과 20종 447개체였다. 집모기류(Culicini sp.)가 가장 우점종이었고(203개체), 두번째 우점종은 집파리(Musca do­mestica)였다. 다양한 생태학적 척도로 수질의 상태를 평가하였다. 전체 생태 점수(total ecological score of benthic macroinvertebrate community, TESB)은 17(St. D)에서 41(St. A)으로 평균은 29였다. St. A에서 부수성 지수와 저서성 대형무척추동물생태 점수(ESB)는 II 등급으로 빈부수성, 수질은 약간 만족이며 보호가 요청되는 수질에 해당되었다. 저서성동물지수(benthic macroinvertebrate index, BMI)은 25.207(St. C)에서 39.348(St. A)까지 이며 평균은 31.810였다. St. C와 St. D의 하천 상태 평가는 강부수성이며 민감종이 결여되어 있었다. 다양도를 나타내는 Shannon-Weaver index (H')는 1.288(St. D)에서 2.250(St. A)였다. H'에 근거한 부수성 정도는 St. A에서는 ${\beta}$-중부수성이었으며 나머지 지점은 ${\alpha}$-중부수성이었다. 지리적 밀도는 1.229(St. A)에서 2.071(St. D)으로 평균은 1.582였다. 송지천에서 사용한 무척추동물을 이용한 여러 수질의 척도는 한국 내 다른 하천에서도 적용할 수 있을 것이다.

• 농업과학연구
• /
• 제39권3호
• /
• pp.319-325
• /
• 2012

This study investigated the user's attitude to the nature trail called Gubulgil in Gunsan reservoir area and evaluated the quality of user's satisfaction of the trails and their facilities by importance-performance analysis (IPA). User's evaluation was achieved through questionnaire survey and total 283 pieces of subjects were used for the analysis. The results are as follows. Firstly, importance value of circularity of trails was very high, and it has great implication to ordinary trails which connect ecological, historical and cultural spots routinely and linearly. Secondly, through the IPA, relatively dissatisfied attributes were parking lots, direction boards, storytelling, convenient facilities and encountering of wildlife. Expansion of parking lots can cause the environmental disruption, so running a shuttle service from Gunsan downtown to the reservoir at weekends can be more reasonable. In case of ecological and historical information delivery, softwares like storytelling contents with sense of realism as well as hardwares of informative signboards are very important in nature trails. Encountering wildlife in trails is fascinating experience but it means visitors may disturb wildlife habitats. So route design should be done very carefully not to intrude their territories.

• Journal of the Korean Wood Science and Technology
• /
• 제33권5호통권133호
• /
• pp.21-28
• /
• 2005

For the proper conservation of wooden cultural properties, non-destructive evaluation (NDE) method, which can be used to quantitatively evaluate the internal state of wood members, are needed. In this study, an ultrasonic CT system composed of portable devices was attempted, and the capacity of this system was verified by reconstructing the CT images for two phantoms and two artificially defected specimens. Results from this study showed that the sizes of detected defects were enlarged and the shapes were distorted on the CT images. Also, the positions were shifted somewhat toward the surface of specimen, which is regarded due to the anisotropic property of wood. Compared to the filtered back-projection method, SIRT (simultaneous iterative reconstruction technique) method was determined to be more efficient as the algorithm of image reconstruction for wood. A new ultrasonic CT system is thought to be used as a NDE method for wood. However wood characteristics and wave diffraction within wood made it difficult to accurately evaluate the size, shape and position of defects. To improve the quality of CT image of wood, more research including the relationship between wood and ultrasound is needed, and wood properties should be taken into consideration on the image reconstruction algorithm.

• 한국환경과학회지
• /
• 제28권3호
• /
• pp.371-384
• /
• 2019

The purpose of this study was to propose an efficient management plan for purchased land considering the hydrological, watershed characteristics and ecological functions of the target land and surrounding area based on the result of monitoring the water quality improvement effect obtained by purchasing the land in the watershed area in the Geum river system. For this purpose, this study investigated through literature review, and examined ways to apply them to this research by deriving implications from a comprehensive analysis of previous research cases. After that, the components of assessment were derived to evaluate the ecological function of the purchase land, and the ecological function evaluation model for each land and area was proposed. In order to select purchase and restoration priorities of the land, this study analyzed the ecological status of the purchased land in main watersheds and tributaries using Arc GIS ver 10.1. Through this, a process to select restoration priorities was developed. And this study constructed the integrated management process with proposing a mid - to long - term plan by integrating the purchased land valuation and restoration priority selection process. Based on this process, this study suggested an effective management plan for purchased land through the integrated ecological management system of lands purchased. It can be used systematically in appraisal valuation, land purchase system, restoration project, and follow-up management of land purchase.

• 시스템엔지니어링학술지
• /
• 제19권1호
• /
• pp.107-113
• /
• 2023

For one-shot systems such as 81mm high-explosive ammunition, research on performance prediction is insignificant due to research manpower infrastructure and lack of interest and difficulties in securing field data, which can only be done by special task workers. In order to evaluate the actual range of ammunition, the storage ammunition reliability evaluation checks the range by firing actual ammunition through a functional test. Test evaluation is a method of extracting a sample from the population, launching it, and recording the results accordingly. As a result of these tests, the range, which is an indicator of ammunition performance, can be measured differently according to meteorological factors such as temperature, atmospheric pressure, and humidity according to the location of the test site. In this study, various environmental factors generated at the test site and storage period analyze the correlation with the range, which is the performance of ammunition, and analyze the priority of importance for each factor and the numerical standards that environmental factors affect range. Through this, a new approach to one-shot system performance prediction was presented.

• 한국대기환경학회지
• /
• 제18권6호
• /
• pp.527-538
• /
• 2002

In this study, the performance of sampling and of analytical methodology was examined against a number of selected volatile organic compounds (VOCs) in the ambient air. The canister-based sampling method for VOCs has been a viable and widely used approach that is based on research and evaluation performed over the past several years. VOCs were determined using canisters by GCMSD analysis. A total of target analyses in this study included approximately 30 VOCs designated in TO-l4A categories including BTEX. The methodology for QC(quality control) was intensively investigated with a wide range of performance criteria such as; (1) cleanliness of canisters, (2) reproducibility of diluter, (3) instrumental detection limits of preconcentrator and GCMSD, and (4) precision and accuracy of GCMSD. For most of the compounds tested, precision was less than $\pm$5%, IDL was 0.2 ppbv, accuracy was $\pm$5%, respectively. This study demonstrated that the combination of canister sampling and GC/MSD analysis could be reliably applied to the measurements of BTEX in ppbv levels that are typically observed in/outdoor air environment.

• 한국환경복원기술학회지
• /
• 제10권3호
• /
• pp.71-87
• /
• 2007

In order to improve and manage rationally for Youngdam creek in Haman-gun, the channel change, water quality and ecological adaptation etc. were evaluated by monitoring during three years. The distinct differences of channel characteristics appeared in the extents of bed excavation and the revetment methods because overall reconstruction was occurred intense disturbance of width expansion and levee construction etc. The scour and deposition were caused according to channel characteristics of ripple and pool, and the adaptation of vegetation was distinguished from each revetment methods clearly. Water quality was maintained first class on the basis of BOD as 0.5~1.5mg/${\ell}$. The vegetation appeared in 380 species close-to-nature river improvement before, but 64 species it after one year, 159 species it after two year and 158 species it after three year. The animal life appeared in 123 species of close-to-nature river improvement before, but 103 species it after one year, 116 species it after two year and 119 species it after three year.

• 한국대기환경학회지
• /
• 제29권6호
• /
• pp.801-810
• /
• 2013

A field study was conducted to evaluate air quality from gas stations with and without Stage II vapor recovery systems that are currently used to reduce VOCs. The THC and VOCs levels were monitored for the test at three locations (inside office, around refueling area, site boundary) from a total of five gas stations. The results showed a considerable reduction in THC concentration which ranged from 48.7% to 81.8% with and without the operation of the Stage II VRS. Acoording to our comparative analysis, BTEX and other 19 VOCs levels were also significantly reduced with Stage II vapor recovery systems.