• Title/Summary/Keyword: Quality Efficiency Evaluation

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A Study on the Stability and Sludge Energy Efficiency Evaluation of Torrefied Wood Flour Natural Material Based Coagulant (반탄화목분 천연재료 혼합응집제의 안정성 및 슬러지 에너지화 가능성 평가에 관한 연구)

  • PARK, Hae Keum;KANG, Seog Goo
    • Journal of the Korean Wood Science and Technology
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    • v.48 no.3
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    • pp.271-282
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    • 2020
  • Sewage treatment plants are social infrastructure of cities. The sewage distribution rate in Korea is reaching 94% based on the sewage statistics based in the year of 2017. In Korean sewage treatment plants, use of PAC (Poly Aluminum Chloride) accounts for 58%. It contains a large amount of impurities (heavy metal) according to the quality standards, however, there have been insufficient efforts to reinforce the standards or technically improve the quality, which resulted in secondary pollution problems from injecting excessive coagulant. Also, the increase in the use of chemicals is leading to the increases in the annual amount of sewage sludge generated in 2017 and the need to reuse sludge. As such, this study aims to verify the possibility of reusing sludge by evaluating the stability of heavy metals based on the injection of coagulant mixture during water treatment which uses the torrefield wood powder and natural materials, and evaluating the sedimentation and heating value of sewage sludge. As a result of analyzing heavy metals (Cr, Fe, Zn, Cu, Cd, As, Pb, and Ni) from the coagulant mixture and PAC (10%), Cr, Cd, Pb, Ni, and Hg were not detected. As for Zn, while its concentration notified in the quality standards for drinking water is 3 mg/L, only a small amount of 0.007 mg/L was detected in the coagulant mixture. Maximum amounts of over double amounts of Fe, Cu, and As were found with PAC (10%) compared to the coagulant mixture. Also, an analysis of sludge sedimentation found that the coagulant mixture showed a better performance of up to double the speed of the conventional coagulant, PAC (10%). The dry-basis lower heating value of sewage sludge produced by injecting the coagulant mixture was 3,378 kcal/kg, while that of sewage sludge generated due to PAC (10%) was 3,171 kcal/kg; although both coagulants met the requirements to be used as auxiliary fuel at thermal power plants, the coagulant mixture developed in this study could secure heating values 200 kal/kg higher than the counterpart. Therefore, utilization of the coagulant mixture for water treatment rather than PAC (10%) is expected to be more environmentally stable and effective, as it helps generating sludge with better stability against heavy metals, having a faster sludge sedimentation, and higher heating value.

A Study on the Quality Improvement of Brain Perfusion SPECT Image (뇌혈류 단일광자방출단층촬영 영상 품질 향상에 대한 연구)

  • Kil, Sang-Hyeong;Lim, Yung-Hyun;Park, Gwang-Yeol;Cho, Seong-Mook
    • The Korean Journal of Nuclear Medicine Technology
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    • v.23 no.2
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    • pp.13-19
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    • 2019
  • Purpose Tc-99m HMPAO is widely used radiopharmaceutical for brain perfusion SPECT. Tc-99m HMPAO is chemically unstable and is liable to show deterioration of labeling efficiency due to high incidence of secondary Tc-99m HMPAO complex, free pertechnetate and reduced-hydrolyzed Tc-99m. In this study, we investigated whether sialogogues administration could reduce the impurities of Tc-99m HMPAO. Materials and Methods In thirty subjects(20 male and 10 female, age range 19~89 years, mean age $60.7{\pm}14.5years$), brain perfusion SPECT were performed at basal and citric acid stimulation states consecutively after injection of 555 MBq of Tc-99m HMPAO. In the salivary glands, the uptake coefficient was calculated using Siemens processing program. Statistical comparison between before and after the citric acid stimulation performed paired t-test. P value less than 0.05 was regarded as statistically significant. Results Salivary glands uptake was $12900{\pm}3101$ counts in basal and $10677{\pm}2742$ counts in citric acid stimulation states. Unnecessary impurities in the body is much decreased after citric acid administration(t=10.78, P<0.05). The image quality was much improved after administration of citric acid and the regional cerebral perfusion was clearly from demarcated the background. Conclusion The impurity is distributed throughout the body particularly in the salivary glands and nasal mucosa when Tc-99m HMPAO brain perfusion SPECT is performed. If this impurities is not removed, the quality of the image may deteriorate, resulting in errors in visual evaluation. The use of sialogogues could be helpful for decreasing unnecessary impurities in the body.

Evaluation of MR Based Respiratory Motion Correction Technique in Liver PET/MRI Study (Liver PET/MRI 검사 시 MR 기반 호흡 움직임 보정 방법의 유용성 평가)

  • Do, Yong Ho;Lee, Hong Jae;Kim, Jin Eui;Noh, Gyeong Woon
    • The Korean Journal of Nuclear Medicine Technology
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    • v.22 no.1
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    • pp.15-22
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    • 2018
  • Purpose Respiratory motion during PET/MRI acquisition may result in image blurring and error in measurement for volume and quantification of lesion. The aim of this study was to evaluate changes of quantitative accuracy, tumor size and image quality by applying MR based respiratory motion correction technique (MBRMCT) using integrated PET/MR scanner. Materials and Methods Data of 30 patients (aged $62.5{\pm}10.2y$) underwent $^{18}F-FDG$ liver PET/MR (Biograph mMR 3.0T, Siemens) study were collected. PET listmode data for 7 minutes was simultaneously acquired with maximum average gate (MAG), minimum time gate (MTG) and non gate (NG) T1 weighted MR images. Gated PET reconstruction was performed using mu-maps generated from MAG and MTG by setting 35% of efficiency window. Maximum SUV ($SUV_{max}$), peak SUV ($SUV_{peak}$), tumor size and full width at half maximum (FWHM) in the z-axis direction of MAG, MTG and NG PET images were evaluated. Results Compared to NG, mean $SUV_{max}$ and $SUV_{peak}$ were increased in MAG 13.15%(p<0.0001), 8.66%(p<0.0001), MTG 13.27%(p<0.0001), 8.80%(p<0.0001) and mean tumor size and FWHM were decreased in MAG 14.47%(p<0.0001), 15.49%(p=0.0004), MTG 14.89%(p<0.0001), 15.79%(p=0.0003) respectively. Mean $SUV_{max}$ and $SUV_{peak}$ of MTG were increased by 0.07%(p=0.8802), 0.13%(p=0.7766). Mean tumor size and FWHM of MTG were decreased by 0.49%(p=0.2786), 0.36%(p=0.2488) compared to MAG. There was no statistically significant difference between MAG and MTG which increase total scan time for about 7 and 2 minutes. Conclusion SUV, accuracy of tumor size and spatial resolution were improved in both of MAG and MTG by applying MBRMCT without installing additional hardware in liver PET/MR study. More accurate information can be provided with the increase of 2 minutes scan time if applying MTG of MBRMCT to various abdominal PET/MR studies affected by respiratory motion.

Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2013 (설비공학 분야의 최근 연구 동향 : 2013년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.12
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    • pp.605-619
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    • 2014
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

Recent Progress in Air Conditioning and Refrigeration Research - A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2004 and 2005 - (공기조화, 냉동 분야의 최근 연구 동향 -2004년 및 2005년 학회지 논문에 대한 종합적 고찰-)

  • Choi, Yong-Don;Kang, Yong-Tae;Kim, Nae-Hyun;Kim, Man-Hoe;Park, Kyoung-Kuhn;Park, Byung-Yoon;Park, Jin-Chul;Hong, Hi-Ki
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.19 no.1
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    • pp.94-131
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    • 2007
  • A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2004 and 2005 has been done. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD and flow visualization(PIV, PTV and LDV methods) technologies were widely applied for developing facilities and their systems. (2) The research trends of the previous two yews are surveyed as groups of natural convection, forced convection, electronic cooling, heat transfer enhancement, frosting and defrosting, thermal properties, etc. New research topics introduced include natural convection heat transfer enhancement using nanofluid, supercritical cooling performance or oil miscibility of $CO_2$, enthalpy heat exchanger for heat recovery, heat transfer enhancement in a plate heat exchanger using fluid resonance. (3) The literature for the last two years($2004{\sim}2005$) is reviewed in the areas of heat pump, ice and water storage, cycle analysis and reused energy including geothermal, solar and unused energy). The research on cycle analysis and experiments for $CO_2$ was extensively carried out to replace the Ozone depleting and global warming refrigerants such as HFC and HCFC refrigerants. From the year of 2005, the Gas Engine Heat Pump(GHP) has been paid attention from the viewpoint of the gas cooling application. The heat pipe was focused on the performance improvement by the parametric analysis and the heat recovery applications. The storage systems were studied on the performance enhancement of the storage tank and cost analysis for heating and cooling applications. In the area of unused energy, the hybrid systems were extensively introduced and the life cycle cost analysis(LCCA) for the unused energy systems was also intensively carried out. (4) Recent studies of various refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and of alternative refrigerants including carbon dioxide. Efficiency of various compressors and expansion devices are also dealt with for better modeling and, in particular, performance improvement. Thermoelectric module and cooling systems are analyzed theoretically and experimentally. (5) According to the review of recent studies on ventilation systems, an appropriate ventilation systems including machenical and natural are required to satisfied the level of IAQ. Also, an recent studies on air-conditioning and absorption refrigeration systems, it has mainly focused on distribution and dehumidification of indoor air to improve the performance were carried out. (6) Based on a review of recent studies on indoor environment and building service systems, it is noticed that research issues have mainly focused on optimal thermal comfort, improvement of indoor air Quality and many innovative systems such as air-barrier type perimeter-less system with UFAC, radiant floor heating and cooling system and etc. New approaches are highlighted for improving indoor environmental condition as well as minimizing energy consumption, various activities of building control and operation strategy and energy performance analysis for economic evaluation.

Evaluation of Early Productivity of High Density 'Fuji' Apple Orchards by Planting Well-feathered Trees/M.9 EMLA ('후지' 사과의 우량 측지묘/M.9 EMLA를 이용한 밀식재배원의 조기 생산성 평가)

  • Yang, Sang-Jin;Park, Moo-Yong;Song, Yang-Yik;SaGong, Dong-Hoon;Yoon, Tae-Myung
    • Horticultural Science & Technology
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    • v.28 no.3
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    • pp.374-380
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    • 2010
  • Well-feathered (5.2 feathers, stem diameter 13 mm) trees of 'Fuji' apple/ M.9 EMLA were planted at $4.0{\tiems}1.5$ m and whip trees (stem diameter 10 mm) of 'Fuji'/M.26 at $4.0{\times}2.0$ m were trained to the slender spindle. The productivity and yield efficiency of two orchard systems were compared for 6 years. The canopy volume of the tree/M.9 EMLA reached $2.07m^3$ in 2nd year and increased slowly to almost the targeted tree volume of $2.9m^3$ in 4th year. Trees/M.26 grew slowly at the begin but from 3rd year the tree volume expanded quickly to reach $5.6m^3$ in 5th year, covering over the allowed space. Yield of M.9 EMLA per 10a increased from 0.3 ton in 2nd year to 4.6 ton in 5th year, and 5.0 ton in 6th year, but yield of M.26 per 10a increased from 0.5 ton in 3rd to 2.9 ton in 6th year. Cumulative yield per 10a up to 6th year was 13.9 ton for M.9 EMLA but only 9.8 ton for M.26. Fruit weight for M.9 EMLA was heavier than that for M.26. In conclusion, the high density planting system with well-feathered trees/M.9 EMLA was better than the conventional wide planting system with whip trees/M.26.

Effect of Irradiation and Blanching on the Quality of Juices of Spuriopinella bracycarpar During Storage (감마선 조사 및 블랜칭처리에 의한 참나물 녹즙의 선도유지효과)

  • Oh, Deog-Hwan;Ham, Seung-Shi;Lee, Sang-Young;Park, Boo-Kil;Kim, Sang-Heon;Chung, Cha-Kweon;Kang, Il-Jun
    • Korean Journal of Food Science and Technology
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    • v.30 no.2
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    • pp.333-340
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    • 1998
  • The research was investigated to determine the effect of irradiation or blanching either alone or in combination on the shelf-life of juices of Spuriopinella bracycarpar during storages. The juices was made from fresh or blanced Spuriopinella bracycarpar and gamma irradiated at the doses (0.5 kGy to 5 kGy). Microbial growth, color change, vitamin C, and sensory evaluation were evaluated during storage at 4 and $25^{\circ}C$. Blanched juices had little effect on the inhibition of microbial growth compared to that of fresh juices. However, significant reduction of microbial counts was observed in the 0.5 kGy irradiation of both juices and inhibition efficiency was greatly increased when irradiated juices was stored at $4^{\circ}C$ rather than at room temperature. Fresh juices without irradiation were little different from the irradiated fresh juices until 20d storage on color change because the juices was rapidly browned immediately after getting the juices from extractor, but blanched juices showed more bright and clear color than that of fresh juices. However, irradiated blanched juices showed greatly reduced the L, a, and b value compared to the non-irradiated blanched juices during storage. The loss of vitamin C from non-irradiated fresh juices was increased during storage and the irradiated fresh juices had little effect on the vitamin C change compared to the non-irradiated fresh juices. However, blanched juices showed less reduction of vitamin C than fresh juices and the irradiated blanched juices had little difference on the vitamin C change compared to the non-irradiated blanched juices, and both treatment showed less vitamin C loss at $4^{\circ}C$ storage. Fresh juces showed more strong grass flavor and biterness than blanched juices and irradiated fresh juices showed little difference on brightness, grass flavor, bitterness, freshness and acceptability, but irradiated blanched juices had better sensory evaluation on grass flavor, bitterness, freshness, and acceptability than non-irradiated branched juices.

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Strategies for Public Health Service Development in the Times of Local Autonomy (지방자치시대의 공공보건사업 발전 전략)

  • 박정한
    • Health Policy and Management
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    • v.12 no.3
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    • pp.1-22
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    • 2002
  • Health is a fundamental human right and a sine qua non for happiness of people and for national development. Government has a responsibility for the provision of health services for their people. Recent changes of disease pattern, i.e. decrease of Infectious diseases and increase of chronic and degenerative diseases Including cancer and cardiovascular diseases, together with universal coverage of health insurance and improved living standard have prompted medical care utilization and skyrocketed the national health expenses. The goal of national health policy is improving the quality of life through the betterment of health level. To achieve this goal it is necessary to establish a healthcare system for lifetime, to improve the efficiency of healthcare delivery system, and to strengthen the public health services for disease prevention and health promotion. The current public health service programs are Inefficient due to an inconsistent policy for health service program, lack of health information system, irrational health program planning and evaluation, and Inadequate training of health workers. Local government has a legal responsibility for health service program planning and promoting the competence of health workers. Thus, municipal and provincial health departments should expand their roles and strengthen their function. The strategies for developing public health service programs at local level are ${\circled}1$ stipulating the goals of health policy, ${\circled}2$ promoting the ability for health program planning and evaluation, ${\circled}3$ establishing health information and surveillance system, ${\circled}4$ training of health workers, ${\circled}5$ establishing an institution for health information management and training of health workers, and ${\circled}61$ collaboration with local universities.

Application of BASINS/WinHSPF for Pollutant Loading Estimation in Soyang Dam Watershed (소양강댐 유역의 오염부하량 산정을 위한 BASINS/WinHSPF 적용)

  • Yoon, Chun-Gyeong;Han, Jung-Yoon;Jung, Kwang-Wook;Jang, Jae-Ho
    • Korean Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.201-213
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    • 2007
  • In this study, the Batter Assessment Science Integrating point and Nonpoint Sources (BASINS 3.0)/window interface to Hydrological Simulation Program-FPRTRAN (WinHSPF) was applied for assessment of Soyang Dam watershed. WinHSPF calibration was performed using monitoring data from 2000 to 2004 to simulate stream flow. Water quality (water temperature, DO, BOD, nitrate, total organic nitrogen, total nitrogen, total organic phosphorus and total phosphorus) was calibrated. Calibration results for dry-days and wet-days simulation were reasonably matched with observed data in stream flow, temperature, DO, BOD and nutrient simulation. Some deviation in the model results were caused by the lack of measured watershed data, hydraulic structure data and meteorological data. It was found that most of pollutant loading was contributed by nonpoint source pollution showing about $98.6%{\sim}99.0%$. The WinHSPF BMPRAC was applied to evaluate the water quality improvement. These scenarios included constructed wetland for controlling nonpoint source poilution and wet detention pond. The results illustrated that reasonably reduced pollutant loadin. Overall, BASINS/WinHSPF was found to be applicable and can be a powerful tool in pollutant loading and BMP efficiency estimation from the watershed.

Current status of global seed industry and role of golden seed project in Korea (국내외 종자산업의 현황과 GSP사업의 역할)

  • Shin, Wan Sik
    • Journal of Plant Biotechnology
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    • v.42 no.2
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    • pp.71-76
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    • 2015
  • Developed countries have set seed industry as a new growth engine, which demands strong support from the government. Multinational seed companies such as Monsanto and DuPont have made huge financial investment to secure their major roles in the global market. To spur domestic seed industry performance, Korean government laid out the foundation for developing seed industry through policy promotion in the late 2000s. In this paper, I look at the current state of the domestic and international seed market to provide information for improving the efficiency of the propulsion of the Golden Seed Project (GSP) along with its vision. The increasing size of global giant companies has been regarded to monopolize the world seed industry wherein ten renowned companies occupy 73% of the overall global market. In effect, this causes a price hike due to limited seed choices. Domestic seed market has been stuck in a range due to a sustained low agricultural production resulting in decreased seed demand and market size. Though breeding technologies for rice and vegetables are world-class, the technologies for top global crops such as cabbage, paprika, and forage are insufficient therefore professionals in this field are not easily employed. Moreover, there is a lack in appropriate infrastructure set up in the universities which adds to ineffective training of professionals. Being a key-supporting industry for agriculture, seed industry should be granted with strong and sustainable investment support from the government. In view thereof, GSP, which started in 2012, ambitions to spur researches outlined by excellent professionals in universities and seed companies aimed to drive seed export volume and quality and attain domestic seed self-sufficiency through adoption of export- and import-substitution seed types (10 varieties each) development strategies. To develop Korea's seed industry excellent achievement of GSP's goals should be drawn successfully and to do this beside development of high quality seeds, support programs for promotion of seed exports are also needed.