• Journal of the Korean GEO-environmental Society
• /
• v.12 no.7
• /
• pp.23-29
• /
• 2011

The oxidation slag has been widely used in civil engineering project, whereas the reduced slag from electric furnace has yet to be applied. Consequently in order to find out the recycling method in civil engineering field, the mineral compositions of the reduced slag were analyzed and some tests on water quality were performed to estimate the potential release of toxic compounds. Slag-soil mixtures of 0, 10, 20 and 30%(dry weight) soil were prepared in lysimeter columns and the effluents were collected with the period of one, two and four week options in closed system, respectively. The result from qualitative and quantitative analysis using X-ray Diffraction(XRD) and X-ray Fluorescence(XRF) indicates that the main mineral of the reduced slag is $Ca_2(SiO_4)$, a kind of calcium silicate. Also, the leaching medium analyzed by Inductively Coupled Plasma Optical Emission Spectroscopy(ICP-OES) showed that main heavy metals such as Al, Fe and Mn are included in the reduced slag due to the effect of steel production process. It can be seen that the leachate does not violate the regulation guide line of waste material of heavy metal. Also the pH levels were increased from pH 6.9 for 0% soil to pH 10 for 30% soil. However the influence on leachate circulation period of one through four weeks was negligible.

• Food Science and Industry
• /
• v.49 no.2
• /
• pp.25-33
• /
• 2016

우리나라의 발효식품 산업의 규모는 2010년 약 4조 원으로 식품 산업 전체의 4.0%정도이며, 이 중 전통 발효식품이 50.0% 수준으로 전체 식품 산업 대비 비중은 2.0%에 불과하지만, 발효제품의 세계 시장 규모는 2000년 152억 달러, 2010년 730억 달러로 급속한 성장으로 확대되고 있다. 국내 소금시장의 규모는 2010년 기준 1,300억 원이며, 전 세계적으로 나트륨 대체 염미제의 시장수요는 절실히 필요한 실정으로, 최근 2,000억 원대 규모를 유지하고 있는 간장 시장에서 염도를 낮춘 '저염 간장'매출 성장세를 보이고 있어 소금을 줄이는 식생활 개선에 대한 교육 홍보와 더불어 '나트륨 저감화 식품 개발의 필요성'이 국민건강증진, 경제성 측면에서 날로 커지고 있다. 또한, 2007년부터 웰빙 열풍으로 자연조미료 제품의 비중이 크게 늘어나는 추세이며, 100% 천연재료로 사용하여 소비자용 제품 출시 등 다양한 변화를 가져온 결과, 자연조미료 시장은 2008년 151억 3,200만 원의 매출규모에서 215억 2,600만원으로 무려 42.3%를 차지했으며, 저염을 위하여 활용하는 저염 소금도 연령대가 높아질수록 선호도가 높아지는 있다는 보고가 있다. 식품의약안전처의 '나트륨 저감화 사업'은 2012년부터 연차별로 가공식품의 나트륨 저감화 가이드라인을 개발하여 가공식품 생산업체들의 참여를 유도하며, 다양한 홍보를 펼쳐 2014년 6월 기준으로 165개 제품의 나트륨이 저감화 되었으며, 2015년에는 95종의 면류제품의 나트륨 함량이 약 20% 이상 저감되는 실적을 보여주었다. 여러 지역자체 단체들은 지역의 특성을 최대한 살려 다양한 발효산업 육성을 진행하고 있음에 영남권의 장류 업체를 대상으로 나트륨 섭취량을 줄일 수 있도록 '경북 발효식품 수출농업기술지원단'은 식품의약품안전처와 연계하여 지속적으로 가공식품 중 나트륨 저감화에 노력을 할 것이며 이에 대기업과 함께 중소기업들의 참여도를 높이기 위해 현장 컨설팅을 지역적으로 실시할 계획으로 각 지역별 업체들의 참여도를 높일 계획이다. 이를 통해 전통 발효식품이 기능성을 유지하면서 나트륨 함량을 줄인 건강식품으로 우리나라 식품산업 발전에 기여하고자 노력할 것이다. 향후 발효산업 중 한류의 매운맛, 김치 등을 시작으로 고성장이 기대되는 세계화 전략 품목이며 지역 농산물을 활용한 발효식품 세계화를 위하여 나트륨 저감화는 반드시 선행되어야 할 것으로 생각된다.

• Journal of Apiculture
• /
• v.32 no.3
• /
• pp.181-189
• /
• 2017

Lysinibacillus fusiformis has been suspected to be a pathogen of Bombus terrestris in Korea since 2008. In this study, we developed the rapid detection method for the L. fusiformis by utilizing the Ultra-rapid PCR. After optimizing of L. fusiformis-specific Ultra-rapid PCR, it can detect the existence of $1.0{\times}10^8$ L. fusiformis-specific DNA molecules in 4 minute and 22 seconds. Even, only 10 molecules could be detected quantitatively using this method. In addition, for the first time, in our knowledge, L. fusiformis was detected using proposed method from bumblebee produced commercially in Korea. Not only in the laboratory but also in the field, L. fusiformis-specific Ultra-rapid PCR would be applied and might be expected as convenient tools at production of bumblebee or inspection for the import and export of bumblebee.

• Journal of Sensor Science and Technology
• /
• v.30 no.3
• /
• pp.154-164
• /
• 2021

In this study, the IoT sensor technology required for improving the survival rate and high-density productivity of individual shrimp in smart shrimp farming (which involves the usage of recirculating aquaculture systems and biofloc technology) was analyzed. The principles and performances of domestic and overseas water quality monitoring IoT sensors were compared. Furthermore, the drawbacks of existing aquaculture monitoring technologies and the countermeasures for future aquaculture monitoring technologies were examined. In particular, for farming white-legged shrimp, an IoT sensor was employed to collect measurement indicators for managing the water quality environment in real-time, and the IoT sensor-based real-time monitoring technology was then analyzed for implementing the optimal farming environment. The results obtained from this study can potentially contribute to the realization of an autonomous farming platform that can improve the survival rate and productivity of shrimp, achieve feed reduction, improve the water quality environment, and save energy.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.24 no.5
• /
• pp.119-125
• /
• 2020

Research on high-attenuation concrete for the vibration reduction performance by mixing epoxy-based synthetic resins and aggregates is actively being conducted. The curing time of high-attenuation concrete is very short because water is not used, and the physical and dynamic properties are very excellent. therefore, it is expected to be widely used in building structures requiring reduction of interior-floor noise and vibration. Furthermore, A way to expand the applicability of the high-damping concrete mixed with polymer in the field of reinforcement material have been variously studied. In order to replace polymer concrete with ordirnary concrete and existing anti-vibration reinforcement material, it is necessary to review overall vibration reduction performance considering physical properties, dynamic properties, productivity and field applicability. In this study, the physical and dynamic properties of polymer concrete by epoxy mixing ratio compared with ordirnary concrete. As a result, the elastic modulus was similar. On the other hand, polymer concrete for the compressive, tensile, and flexural strengths was quite more excellent. In particular, the measured tensile strength of polymer concrete was 4-10 times higher than that of ordirnary concrete. it was a big difference, and the frequency response function and damping ratio was studied through modal test and finite element analysis model. The dynamic stiffness of polymer concrete was 20% greater than that of ordirnary concrete, and the damping ratio of polymer concrete was approximately 3 times more than that of ordirnary concrete.

• Journal of Mushroom
• /
• v.18 no.4
• /
• pp.297-302
• /
• 2020

Five varieties of mushrooms, including Sae-do, were examined using farm field tests to determine their morphological characteristics and quality by performing harvest flush. Considering the cultivation characteristics of the varieties studied, the parts related to mushroom generation and production showed almost similar characteristics. Overall, the mycelial forces were similar; however, in the evaluation of plantation tests performed by farmers, "saedo" was found to be the strongest and "saehan" was considered to be the weakest. Weights of fruiting bodies were related more for compost status and regimen of use than for breeding, and it was difficult to distinguish between the weights of fruiting bodies of the varieties studied. Regardless of the variety, pileus diameter, pileus thickness, and stem length of Dalseong-gun, Yongin-si, and Boryeong-si decreased as the harvest flush progressed. However, stem thickness tended to increase in the second and third flush compared to that in the first flush, regardless of the variety. However, the Gyeongju-si farms could not identify any trends attributable to varieties and harvest flushes. The pileus size and stem length of the fruiting bodies of varieties from Buyeo farms decreased with the progression of the harvest flush. However, pileus thickness and stem thickness did not show any specific tendency of growth among the varieties studied. The differences in the morphological characteristics of mushroom varieties in each harvest cycle are expected to be caused by differences in the supply of nutrients in the medium, the quality of the compost used, and the cultivation environment rather than the variety.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.12
• /
• pp.888-895
• /
• 2020

In the construction industry, off-site construction (OSC) is drawing attention as a production method due to changes in working hours and the supply and demand of manpower. In 1991, there was a policy of spreading and expanding the use of precast concrete (PC) apartment homes, but they have not been actively used so far since they were discontinued due to quality problems. In this study, policy tasks were analyzed to motivate the application of OSC-based PCs in the apartment housing sector, and policy directions were derived by conducting focus group interviews (FGI). Nine policies are suggested regarding the following topics: PC apartment supply quantity provision, priority application of public housing, priority supply of public housing, preferential floor area ratio, funding, tax support, improvement of business area structure, improvement of delivery method, factory certification system, and training of experts. The results of the FGIs are as follows. First, in order to revitalize PC apartment homes, leading efforts from the public sector are required. Second, rather than reorganizing the business sector or introducing a new delivery method, a policy direction that induces the strengthening of cooperation is desirable. Third, PC activation should be promoted on an institutional basis for securing appropriate construction costs and quality.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.12
• /
• pp.449-455
• /
• 2020

Inventory management is one of the important business functions for manufacturing companies to determine market responsiveness. Customers' needs are diversifying, and the life cycle of products is decreasing, thus increasing the importance of inventory management. However, for small-scale manufacturing companies, investing in an IT system for inventory management is practically difficult. In this study, we introduce an inventory and warehouse management model that can be applied simply and quickly in small-scale manufacturing companies. Firstly, we introduce the concept of the properties of inventory and provide an analytical methodology based on the age and quantity of the inventory. Secondly, in accordance with the properties of the inventory, we introduce location management rules for warehouse operation. To apply the proposed model, we studied a wallpaper manufacturing company and verified the applicability of the proposed methods in the field. The proposed model can be applied immediately as part of on-site improvement activities by small-scale manufacturing companies, and inventory management activities are expected to reduce bad long-term inventory and further secure storage capacity for warehouses.

• Journal of the Korean Institute of Gas
• /
• v.24 no.6
• /
• pp.18-27
• /
• 2020

This study presents flow assurance analysis in subsea pipeline considering system availability of topside in LNG-FPSO. A hydrate management strategy was established, which consisted of PVCap experiments, system availability analysis of LNG-FPSO topside, hydrate risk analysis in the pipeline, and calculation of PVCap injection concentration. The experimental data required for the determination of PVCap injection concentration were obtained by measuring the hydrate induction time of PVCap at the subcooling temperatures of 6.1, 9.2, and 12.1℃. The availability of LNG-FPSO topside system for 20 years was 89.3%, and the longest downtime of 50 hours occurred 2.9 times per year. The subsea pipeline model for multiphase flow simulation was created using field geometry data. As a result of risk analysis of hydrate plugging using subsea pipeline model, hydrate was formed at the end of flowline in 23.2 hours under the condition of 50 hours shutdown. The injection concentration of PVCap was determined based on the PVCap experiment results. The hydrate plugging in subsea pipeline of LNG-FPSO can be completely prevented by injecting PVCap 0.25 wt% 2.9 times per year.

• Clean Technology
• /
• v.27 no.2
• /
• pp.174-181
• /
• 2021

This study analyzed the groundwater quality characteristics according to the main source of pollution and quarter (season) by using data from the pollution exclusive monitoring network in the Gyeongsangnam-do area for five years (2013-2017). The main source of pollution was the industrial complex areas, waste mines, and sewage treatment facilities. The analysis items were field measurement items (water temperature, pH, electrical conductivity, dissolved oxygen, oxide reduction potential), positive ions, and negative ions. Water temperature and pH did not vary significantly according to the main source of pollution. In industrial complex areas, the value of electrical conductivity was the highest, and dissolved oxygen value was the lowest. The mean concentration of positive and negative ions was the largest in industrial complex areas, followed by sewage treatment facilities and waste mines. It was shown that the concentration of sodium ion was the highest in industrial complex areas and calcium ion in waste mines and sewage treatment facilities. The concentration of bicarbonate ion was the highest in all main sources of pollution. Water temperature, pH, and concentrations of cations and anions did not vary significantly from quarter to quarter. Of the water quality types, the Na-HCO₃ type accounted for the highest proportion, but the Na-Cl type, which has a high possibility of external contamination, accounted for about 20% of the total data in the pollution exclusive monitoring network.