• Korean Journal of Plant Resources
• /
• v.34 no.5
• /
• pp.478-490
• /
• 2021

We aimed to generate basic breeding data for melon (Cucumis melo L.). A total of 219 melon accessions conserved at the National Agrobiodiversity Center (NAC) in Rural Development Administration (RDA) were used in this study, of which 72 (33%) were collected from India. The majority of accessions showed orange (42%) and white (36%) flesh color. In addition to phenotypic evaluations, the accessions were genotyped using a molecular marker for the carotenoid biosynthesis gene CmOr. DNA fragments of the expected size were amplified in 205 out of 219 accessions. Digestion of the PCR products with HinfI restriction endonuclease showed 100% concordance between phenotype and genotype in green-fleshed accessions, but 98%, 97%, and 80% concordance in orange-, white-, and creamy-fleshed accessions, respectively. Sequence analysis revealed single nucleotide changes in the three positions of SNP1, SNP2 and SNP1int in the CmOr gene among accessions. These newly found alleles suggest that there are multiple mechanisms in determining fruit flesh color in melon. Also, the phenotype data of diverse accessions obtained in this study will be a valuable source for melon breeding.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.11 no.4
• /
• pp.12-23
• /
• 2008

This study has a purpose of setting applicable ecological environment plan items when establishing city development plan. To achieve this purpose, multiple methods of data gathering, documentary surveys, and questionaries research were used in this study. The main findings of this study can be summarized as follows; 1. The appliance of ecological environment plan is appropriate to apply before the establishment of development plan. 2. The items applicable to ecological environment plan establishment step by step is the following. First, it is necessary to prepare the environment improvement plan and ecology restoration on the stage of assigning the area. Second, on the stage of planning development plan, it is required to set the restoration plan of ecological resources and step by step ecological environment plan. Third, on the stage of plan implementation, it is required to set the maintenance guide on ecological environment. 3. The planning items of ecological environment plan are "geographical features and soil", "water resource", "wind resource", "green resource", "circulation of resource", "usage of nature energy" and "habitats", etc. 4. To apply ecological environment plan to the planning of development, it is necessary to specify the clear concepts and specific plan. 5. This study is limited to select generalized planning items and later on, it is necessary to develop detailed planning contents.

• Journal of Korean Society of Water and Wastewater
• /
• v.32 no.2
• /
• pp.153-158
• /
• 2018

In this study, effects of nutrient and inorganic carbon on single cell emergence during the cultivation of microalgae were observed using colonial green algae, Pediastrum duplex. The concentration of inorganic carbon had significant effect on single cell emergence and its growth, but nitrogen and phosphorus concentration showed minor effects. According to P. duplex cultivation experiment, single cell started to be emerged around 500~750 mg-C/L of inorganic carbon concentration and it was bloomed dramatically at the higher values. And growth of P. duplex was started to be surpressed at the single cell formation concentration. From the results, it could be said that when we operate the microalgae systems for cultivation/harvesting or wastewater treatment, in order to avoid single cell formation, inorganic carbon should be maintained to the proper level.

• Corrosion Science and Technology
• /
• v.10 no.2
• /
• pp.60-64
• /
• 2011

Lean duplex stainless steels have been developed in Korea for the purpose of being used in the seawater systems of industry. There are also many important seawater systems in nuclear power plants. These systems supply seawater to cooling water condenser tubes, heat exchanger tubes, related pipes and chlorine injection systems. The flow velocity of some part of seawater systems in nuclear power plants is high and damages of components from corrosion are severe. The considered lean duplex stainless steels are STS329LD (20.3Cr-2.2Ni-1.4Mo) and STS329J3L (22.4Cr-5.7Ni-3Mo) and PRENs of them are 29.4 and 37.3 respectively. Physical, mechanical and micro-structural properties of them are evaluated, and electrochemical corrosion resistance is measured quantitatively in NaCl solution. Critical Pitting Temperatures (CPT)s are measured on these alloys and pit depths are evaluated using laser microscope. Long period field tests on these alloys are now being performed, and some results are going to be presented in the following study.

• Journal of Electrical Engineering and Technology
• /
• v.12 no.3
• /
• pp.1046-1052
• /
• 2017

The load on the power grid of South Korea is expected to grow continuously until the late 2020s, and it is necessary to increase the transfer capacity from the Eastern grid to the Seoul-Gyeonggi region by reinforcing the transmission network for the electric power system to remain stable. To this end, the grid reinforcement by two bipole LCC HVDC transmission systems have been considered on account of the public acceptability and high growth of the fault current level, even though an additional 765kV system construction is more economical. Since the probability of the existing 765kV double circuit transmission line trip is extremely low, a dynamic simulation study was carried out to estimate the efficient HVDC capacity able to stabilize the transient stability by utilizing the HVDC overload capability. This paper suggests the application plan to reduce the HVDC construction capacity with ensuring the transient stability during the 765kV line trip.

• KIEAE Journal
• /
• v.15 no.6
• /
• pp.5-10
• /
• 2015

Purpose: To evaluate the economic performance of grid-connected photovoltaic system in residential house, household electricity bill policy of Korea Electric Power Corporation (KEPCO) must be applied precisely, and market tendency and uncertainty of system also need to be considered. In this study, to evaluate the economic feasibility of PV system, we measured PV power generation and electricity consumption of six of Green home in Daejeon through web based remote monitoring system. Method: We applied Monte-Carlo simulation based on life cycle cost analysis, to reflect an uncertainty of main factor in economic feasibility evaluation of photovoltaic system. Result: First, with deterministic analysis, the difference of NPV of cumulative financial savings among households varied from -3,310 ~ 24,170 thousand won, portraying notably big range. Also the possibility of getting the same result was 50% when applying uncertainty. Second, the higher electricity consumption is, the more economic feasibility of photovoltaic system increases because KEPCO uses progressive taxation in household electricity bill policy. Third, The contribution to variance of electricity price increases in NPV varied from 98.5% to 99.9%. While the inflation rate and annual degradation contributed very little to none.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11c
• /
• pp.729-735
• /
• 2000

Moisture loss of fresh fruits and vegetables is a main cause of deterioration. It resulted not only in the direct quantitative loss, but also in change in appearance, texture and nutrition. To reduce the loss of moisture content during the distribution in the market, fresh products are packaged using plastic films. But, most of the fresh products are packaged manually in Korea. In order to minimize the labor requirement, the packaging machine for fruits and vegetables was developed and tested. Prototype was composed of film feeding unit, bag former, products feeding conveyor, film feeding roller, center sealer, end sealer and discharge conveyor. Green peppers, carrots and perilla leaves were tested with prototype. Prototype could pack 1780, 1390, 1780 bags per hour at the feeding speed of 0.08m/s respectively and 2250, 1810, 2640bags per hour at the feeding speed of 0.10m/s respectively. And packaging speed of green peppers and carrots was improved by 3.7 and 3.4 times compared with manual packaging. The packaging condition with the prototype was good and the products had almost no damages.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.35 no.3
• /
• pp.37-49
• /
• 2007

This study investigated how external environmentally-friendly factors adopted to improve the quality of outdoor spaces have been designed and used in the construction of apartment complexes. The goal of this study is to determine what areas should be improved through environmentally-friendly ways to create natural outdoor spaces in apartment complexes and enhance their availability and usefulness. For this study, 21 environmentally-friendly factors were chosen and a checklist by specific item was prepared. This study examine how these items were applied to basic planning, detail design, and construction in 4 target areas. As a result, it was found that the development of environmentally-friendly residential areas was an ultimate goal of the project during basic planning and design. All target areas focused on developing an inner greens network, eco-pond, brook, and pedestrian track as well as the growth of a variety of plants. Some differences have been observed, however, in terms of method. Furthermore, due to economic and technological problems and poor construction site conditions, green walls/green roofs/pedestrian tracks/use of rainwater have not been properly promoted. These kinds of problems must be improved through the development of environmentally-friendly construction methods and materials, the expansion of natural grounds areas, economic support, a satisfactory repair and maintenance system.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.24 no.1
• /
• pp.1-22
• /
• 2020

An accurate and efficient gradient estimation method on unstructured grid is presented by proposing a switching process between two Least-Square methods. Diverse test cases show that the gradient estimation by Least-Square methods exhibit better characteristics compared to Green-Gauss approach. Based on the investigation, switching between the two Least-Square methods, whose merit complements each other, is pursued. The condition number of the Least-Square matrix is adopted as the switching criterion, because it shows clear correlation with the gradient error, and it can be easily calculated from the geometric information of the grid. To illustrate switching process on general grid, condition number is analyzed using stencil vectors and trigonometric relations. Then, the threshold of switching criterion is established. Finally, the capability of Switching Weighted Least-Square method is demonstrated through various two- and three-dimensional applications.

• Toxicological Research
• /
• v.13 no.4
• /
• pp.353-357
• /
• 1997

The possibility of the allergic encephalomyelitis caused by the combined vaccine (KGCC95VI) for the prophylaxis against Japanese encephalitis and Hantaan virus infection, recently developed by Korea Green Cross Corporation, was investigated in the Hartley guinea pigs. The KGCC-95VI was administered to the guinea pigs subcutaneously to sensitize the animals three times at one month intervals. There were no clinical signs or gross pathological findings. There were no abnormal histopathological findings at cerebrums, cerebellums, brain stems and the spinal cords. The concentration of myelin basic protein was 1.10 ng/dose quantified by ELISA, which met the guide4ine of below 2 ng/ml/dose recommended by American Society of Health -System Pharmacists(AHPS) Drug Information. Accordingly, the KGCC-95VI is considered not to induce any allergic immune responses which may lead to the experimental allergic encephalomyelitis.