• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.438-445
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• 2010

Soils in continuous monoculture cropping system generally have a number of physical and chemical problems. Thus, we studied to investigate selected soil properties in continuous watermelon cropping plots with applications of different soil management practices: 1) conventional farming practice (CFP), 2) chemical fertilizer management practice (FMP), the FMP with different amounts, 0.5, 1.0, and 1.5 t $ha^{-1}$, of oyster shell meal application (FMP-OS 0.5, 1.0, and 1.5 t $ha^{-1}$), and 3) the FMP with different amounts, 2.0, 3.0, and 4.0 t $ha^{-1}$, of peat application (FMP-PT 2.0, 3.0, and 4.0 t $ha^{-1}$) and also to evaluate watermelon quality. Soil pH slightly increased only in the FMP-OS 1.5 t $ha^{-1}$ plot, while it was not changed or decreased a little in other plots. The contents of soil organic matter (SOM) expectedly increased in the FMP-PT plots, whereas it markedly decreased in the FMP-OS plots. The concentrations of exchangeable cations, $Ca^{2+}$, $Mg^{2+}$, and $K^+$, in soils were mostly dropped down in most of the FMP and FMP-PT plots. Otherwise, the exchangeable $Ca^{2+}$ concentration increased a bit in the FMP-OS plots. Also, the concentrations of water-soluble anions, $NO_3^-$, $Cl^-$, ${SO_4}^{2-}$, and ${PO_4}^{3-}$, in soils mostly declined in all the plots applied with the different management practices during the study years. Due to the cation and anion decreases, the electrical conductivity (EC) values in the soils were greatly reduced in the plots. Thus, the soil management practices applied, especially oyster shell meal and peat treatments, might be useful to control soil conditions. However, watermelon quality, such as sugar content and fruit weight, would not be associated with the soil management practices applied.

• Journal of the Korea Institute of Building Construction
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• v.23 no.3
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• pp.285-293
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• 2023

In this research, we embarked on a meticulous analysis of the challenges inherent in real-world scenarios relating to the durability design standards of engineered concrete structures and the assessment of carbonation durability in concrete guidelines. Our investigation brought to light substantial issues concerning constructability and quality assurance. The genesis of these problems is the exclusive application of prescribed strength to exterior walls, neglecting other elements to facilitate smoother licensing procedures. While this methodology aims to mitigate financial constraints in alignment with enhanced standards, it invariably invites complications. Furthermore, it is imperative to resolve the uncertainty surrounding durability evaluations by establishing a clear and definitive objective. Alongside this, actionable steps must be formulated to forestall the emergence of fissures between the floors of residential buildings, particularly apartment complexes. It is equally essential to tackle issues connected to application by devising a comprehensive management strategy for potential cracking during the phase of maintenance.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.115-122
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• 2002

There is various points that should be improved in Fairness such as our contract practice to propose construction projects, project managing and the stakeholders' way of thinking and culture. We consider that the revision of construction related provisions and systems is required but even more, an overall change in business management through the implementation of Integrated Construction Information Management System that will enable the owner, which drives the project, and contractor sharing construction information is required. To mange construction related information in an integrated manner, designing information should be smoothly transferred to purchasing information, and changes are required in order to move ahead to process-oriented work system. Finally information created from various construction organizations should be delivered in an aligned and standardized manner as well. The domestic Nuclear Power Plant Construction has been accepting various technology transfers from U.S, France, Canada and UK, which enabled us to self-support technology and recently even proceeded to the phase exporting our technology to others. However, continuous effort is required to improve internal business efficiency and to respond to external environmental change such aselectricity market deregulation. Recently, in accordance with the result in number of CEO's intention to make progress in IT and improve business efficiency, the number of enterprises introducing Enterprise Resource Planning is increasing. ERP is an innovative tool which changes the way of performing work from organization and department orientation to process-orientation in order to optimize the resources, such as human and material resources, through out the Enterprise by performing BPR which will maximize overall business efficiency of the enterprise, such includes not only construction management, but also business management. KHNP continued to performing large scaled construction projects such as nuclear power plant construction for past 30 years and took the initiatives of large scale project management and Quality management ability in domestic industry by having independent capability of over all construction planning, purchasing and, construction and start up management etc. To maintain our leading position of improving construction management technology based on our accumulated project management experience and technology, KHNP included construction into our ERP project in purpose of innovating construction business. We would like to discuss the characteristics of nuclear construction business, project management system, information system infrastructure and information sharing system among construction related entities, and implementation practices for information system, and consider how to resolve our practice that should be improved in this thesis.

• Korean Journal of Organic Agriculture
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• v.20 no.3
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• pp.411-422
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• 2012

To investigate the possibility of sustainable agriculture in no-tillage pepper this study was carried out in vinyl greenhouse with organic cultivation having no pesticide certification. 1. Growth and yield in pepper cultivation General growth in pepper was suppressed with decreasing hill spacing, primary branch length, and stem width. Fruit diameter and fruit weight in no-tillage increased significantly, and yield of pepper increased by 10% compared with conventional tillage. From results organic cultivation in no-tillage improved a quality of pepper compared with conventional tillage. 2. Production cost of conventional tillage and no-tillage Production cost of conventional tillage and no-tillage was not different in seed cost, inorganic fertilizer cost, pesticide cost, repair cost, light agricultural tool cost, agriculture facilities depreciation cost and so on. Intermediary goods cost in no-tillage was decreased by 11% for organic fertilizer cost, light and heat expenses and power rate, heavy agricultural tool cost, and repairing expenses compare with conventional tillage. Employment effort cost and work effort cost were decreased, and farm income and farm income rate were increased by 11% and 5%, respectively, in no-tillage. In this work, yield and gross income were increased by 10% and 25%, respectively, in no-tillage. Therefore material cost, intermediary goods cost, working expensive, farm income, and income rate were increased by 34%, 3%, 2%, 52% and 22%, respectively.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.20 no.3
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• pp.71-76
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• 2014

Master packaging system is a technology combining primary and secondary packaging to preserve the fresh produce in the supply chain. Master packaging system with tailor-designed gas transfer and $CO_2$ absorber of $Ca(OH)_2$ was applied to fresh shiitake mushroom in its supply from farm to retail store. The temperature, humidity and package atmosphere were monitored through the distribution and/or storage until the packages were opened to measure the mushroom quality. Conventional perforated individual packages without secondary master pack were prepared and travelled the same path for comparison purpose. While high temperature history was observed in some initial period of actual practice of the mushroom transportation and storage unexpectedly, the package atmosphere around the produce in the master packaging system was maintained at modified atmosphere consisting of $O_2$ concentration of 0.4 to 4.2% and $CO_2$ concentration of 0.7 to 1.7%, which is known to be beneficial for the mushroom preservation. While curing the mushrooms with precooled drying was effective for quality preservation, positive effect of master packaging system could be apparent for the uncured mushroom. Harmonized combination of curing treatment, master packaging system and temperature management was suggested for the best quality preservation of the fresh shiitake mushroom.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.121-130
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• 2018

'Mats-kyeong-chae (Brassica lee ssp. namai cv. Tongssamchoo)', a new type of sweet Korean cabbage for fresh wrapping and soup cooking, was released by the Korea National College of Agriculture and Fisheries. The shelf-life and quality changes of this new cultivar was evaluated by packaging with PP (polypropylene) film bag and storing at three temperatures ($5^{\circ}C$, $15^{\circ}C$, and $25^{\circ}C$). As control, the cabbage was packaged in a corrugated paper box and stored at $25^{\circ}C$. At the storage temperature of $5^{\circ}C$, the degree of freshness, weight loss, hue angle and SPAD on cabbage packaged with PP film bag maintained its good quality and exhibited a longer period of marketable life compared to the samples stored in other treatments. Results showed that the use of PP film packaging and storing at $5^{\circ}C$ could be the optimum condition for commercial storage of 'Mats-kyeong-chae'. Further investigation on other quality parameters according to different packaging methods would be useful in maintaining the quality of 'Mats-kyeong-chae' at postharvest stages.

• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.12-19
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• 2010

Optimum nitrogen fertigation level by soil testing was determined on the growth and yield of eleven-year-old 'Campbell Early' (Vitis labrusca L.) grapevine in a sandy loam soil from 2005 to 2007. Fifty percent of the annual application of the nitrogen rate (195 kg/ha/yr) was top-dressed as basal fertilizer in all treatments, and the remainders were drip-irrigated with fertigation rate at 25 (12.5% of total N, N 1/4 level of the remainder), 50 (25% of total N, N 1/2 level), and 100 mg/L (50% of total N, N 1 level) in intervals of twice (2.1 mm/times) a week for 12 weeks, and the effect of N drip fertigation was compared to control which the N remainder was applied with surface application as an additional fertilizer. The results showed that chlorophyll content reading in SPAD value and N contents of leaves increased as nitrogen fertigation level increased. Also observed was the growth of the internode and stem diameter of shoots which were longest at N 1/2 level among the treatments conducted both in 2005 and 2006. It was also noted that yield of the fruit was different every year, where average yield for three years was recorded highest in N 1/4 level, and lowest in N 1 level compared to control(surface application). Soluble solid content and titratable acidity of fruit juice were also not significant during the treatments, the maturation of fruits tended to be retarded in N 1 level. The study proved that N 1/4 (N 25 mg/L) levels of fertigation based on soil testing was most efficient in obtaining optimum yield and also, fertigation of grapevine at open field condition reduces the use of nitrogen fertilizer.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.132-137
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• 2011

BACKGROUND: This experiment was carried out to evaluate the effect of potassium fertigation on the growth and yield of fourteen years-old 'Campbell Early' grapevine (Vitis labrusca L.) on a sandy loam soil. METHODS AND RESULTS: Potassium application (125 kg/ha/yr) was top-dressed as 30% of annual potassium application in all treatments and the remainders were drip-irrigated with 0 (0% of total K, K0 level of the remainder), 25 (17.5% of total K, K1/4 level of the remainder), 50 (35% of total K, K1/2 level), and 100mg/L (70% of total K, K1 level) in the intervals of 2 times a week for 12 weeks and the effect of K drip fertigation was compared to control treatment in which the K remainder was applied with surface application as additional fertilizer. The growth of stem diameter, leaf number and shoot length were highest in K1/2 (50 mg/L K), but K of mineral contents was lowest in K0. Yield of grapevine was no difference in 2008, but significantly higher K1/2 than other treatments in 2009. However, fruit quality (color degree, brix, acid contents) was no difference among the treatment. CONCLUSION(s): From the results, It is expected that K1/2 levels of fertigation based on soil testing could be more efficient to get optimum yield and save potassium fertilizer than control (surface application) treatments when grapevine was drip-irrigated at open field condition.

• Korean Journal of Food Science and Technology
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• v.43 no.1
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• pp.98-104
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• 2011

The storage quality of fresh buckwheat sprouts, as influenced by pretreatment and packaging within processing steps, was investigated to establish appropriate postharvest handling treatment for the commodity. After harvest, the sprouts were dipped in chlorine water (100 ppm), rinsed twice with clean water, pre-cooled with iced water, de-watered, and packed in plastic trays. Sprout samples taken from each processing step were stored at $5^{\circ}C$ for 6 days to measure quality attributes. Viable cell counts of mesophilic aerobes and coliform bacteria were lower by about 1 log scale in the postharvest treated samples compared to an untreated control, although the initial microbial reduction due to the postharvest treatments was offset by cell growth during storage. All sprout samples showed a decrease of fresh weight by approximately 4% after 6 days of storage. However, moisture and soluble solid contents were maintained at the initial levels of the sprouts. No significant difference in surface color was observed among sample treatments. For sensory properties including discoloration, wilting, decay, and visual quality, there were no significant differences among sample treatments. The present results suggest that proper postharvest processing treatments can exert positive effects on extending the shelf-life of fresh buckwheat sprout.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.831-841
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• 2017

Different timings of coverage by a small paper bag at the young fruit stage were tested in order to evaluate the effect on the protection of fruit damage occurred by disease or pest, and quality deterioration during organic cultivation of 'Hwasan' (Pyrus pyrifolia Nakai) pear cultivar. The occurrence of four major moth populations and two major diseases in pears were monitored from April to September 2015. Among major moths and diseases, Grapholita molesta and pear rust were found often in the organic pear orchard, and they were observed frequently in May. Coverage by a small paper bag at the young fruit stage resulted in better fruit quality and a higher proportion of commercial fruits compared to a coverage timing of conventional paper bag. Interestingly, the fastest coverage timing of a small paper bag at the young fruit stage (when it was covered in April) showed the lowest occurrence of damaged fruits, which indicates that it successfully protected fruits from the damage caused by moths and diseases during April and May. Moreover, this timing of small paper bag coverage did not negatively affect the major qualitative and quantitative characteristics of fruits. These results suggest that early coverage by a small paper bag at the young fruit stage can be considered an efficient management strategy for organic cultivation of 'Hwasan' pear cultivar.