• Proceedings of the Korean Society of Crop Science Conference
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• 1999.11a
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• pp.102-144
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• 1999

The major problems of food crop cultivation in Korea are low yield of most crops except rice. inefficient cultivation techniques for aged farmers. and low international competibility. Therefore, development of cultivation techniques of food crops should aim the yield. quality improvement, labor reduction and production cost. The primary issue for increasing the yield of soybean, barely and wheat is to reduce the yield gap between the farmer's yield and recommended ones of experiment station. More advanced cultivation techniques needs to be developed. and/or the conventional breeding methods to be reconsidered. The newly developed labor-saving mechanized technique needs to reduce labor hours , and the cost of agricultural implements and machineries. In other words the labor-saving mechanized technique should be developed based on the improvement of total farming system as well as systemic fundamental innovation of cultural methods. The efficiency of solar energy use in food production of Korea in 1997 is as low as $0.52{\%}$ so there is much room to increase yield. It is recommendable that the concept of food Production should be changed to energy Producing efficiency Per unit area basis from volume and weight of food materials. Moreover, introduction of resonable cropping system is needed to increase yield of main crops, farmer's income, solar energy use efficiency, and decrease of land service expenditure. Current cropping system emphasized on economic crops. especially in vegetables , is not desirable for resonable use of arable land. stability of agricultural management and staple food crop self-sufficiency ratio. It is desirable to increase food crops . that are energy of carbohydrate and protein rich and land dependent crops. in cropping system. And the agronomist should develop the cultural methods to replace food crops for food self-sufficiency and stable farming management instead of economic crops in current cropping system. Low-input and environmentally-sound crop cultivation techniques, especially nitrogen-reducing culture technique which is directly related to food crop quality, also needs to be developed urgently. The extended cultivation of corn in upland and barely and wheat in lowland as a feed stuffs is recommended to prevent further decrease of food self-sufficiency ratio, which is mainly caused by the high reliance on imported feed grain. It is also considered that the calculation and presentation methods of standard agricultural income needs to be improved. The current calculation method uses unit land area of 10a regardless of crop kinds , characteristics of agricultural management and cultivation scale. So, it is apt to lead misunderstanding of farm income value. Therefore. it should show an income of average farmers for certain number of years. Research and developing system for food producing is not desirable because they are conducted currently individual crop and mono-culture basis. But actual agricultural income is usually earned by cropping system including upland and lowland. For example. the barley and wheat is usually cultivated in double cropping system. The cooperation among research institutes such as university agribusiness. government and farmers is indispensible. The public information and education on importance and consumption habit of food crops is necessary in Korean society to increase food self-sufficiency through nationwide cooperation.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.3_4
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• pp.61-71
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• 1995

Natural ground is a composite consisted of the three phases of water, air and soil paircies. Among the three components, water as a material is weU understood but soil particles are not in foundation engineering. Especially, weathered granite soil generally shows a large volumetric expansion when they freeze. And, the stability and durability of the soil have shown decreased with repetitive freezing and thawing processes. These unique charcteristics may cause various construction and management problems if the soil is used as a construction material and foundation layers. This project was initiated to investigate the soil's physical and engineering characteristics resulting from freezing and freezing-thawing processes. Research results may be used as a basic data in solving various problems related to the soil's unique characteristics. The following conclusions were obtained: The degree of decomposition of weathered granite soil in Kangwon-do was very different between the West and East sides of the divide of the Dae-Kwan Ryung. Soil particles distributed wide from very coarse to fine particles. Consistency could be predicted with a function of P200 as LL=0.8 P200+20. Permeability ranged from 10-2 to 10-4cm/sec, moisture content from 15 to 20% and maximum dry density from 1.55 to 1.73 g /cmΥ$^3$ By compaction, soil particles easily crushed, D50 of soil particles decreased and specific surface significantly increased. Shear characteristics varied wide depending on the disturbance of soil. Strain characteristics influenced the soil's dynamic behviour. Elastic failure mode was observed if strain was less than 1O-4/s and plastic failure mode was observed if strain was more than 10-2/s. The elastic wave velocity in the soil rapidly increased if dry density became larger than 1.5 g /cm$^3$ and these values were Vp=250, Vg= 150, respectively. Frost heave ratio was the highest around 0 $^{\circ}C$ and the maximum frost heave pressure was observed when deformation ratio was less than 10% which was the stability state of soil freezing. The state had no relation with frost depth. Over freezing process was observed when drainage or suction freezing process was undergone. Drainage freezing process was observed if freezing velocity was high under confined pressure and suction frost process was occurred if the velocity was low under the same confined process.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.4
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• pp.179-190
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• 2019

To alleviate financing difficulties of small and medium sized enterprises (SMEs), the government and municipal governments are providing a variety of SME policy funding programs. This study introduced the policy funding program of Gangwon-do and quantitatively analyzed the financial performance of companies supported by the Gangwon-do SME policy fund in the year 2014. Specifically, we compared the financial ratios for three years, from 2013 to 2015, between funded firms and non-funded firms. In addition, we applied a regression analysis to see if the policy funding program contributed to profitability (the operating profit growth and return on equity), stability (the interest coverage ratio and debt-to-equity ratio), and growth (the asset growth and sales growth) of the funded firms. The empirical results show that the firms that received the policy funds did not show any improvement compared to non-funded firms in terms of profitability, stability, and growth. This suggests that Gangwon-do should improve the policy funding program, that currently provides only an interest amount of 2-4% of the corporate loan principal, without any strategic selection criteria for the target funded firms, and without any follow-up management system, after support.

• Journal of Technologic Dentistry
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• v.13 no.1
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• pp.79-97
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• 1991

To improve the management of dental laboratory through the research on the actual condition, this study posed questions on 36 dental laboratories. The results are as follows : 1. The establishment of dental laboratory in Chunbuk was increased between in 1980 and 1986. Especially it has been more increased since 1989. According to the proportion of population the number of the dental laboratories in Chunbuk was much more than that of other provinces and took the first place in september 1990. 2. The ratio between the unlicensed dental technician and the licensed was 24.83% and 67.11% each . The former must be replaced by the licensed. And the latter ought to try to improve their culture and technique. 3. Overtime payment must be paid for those who work above eight hours. 4. It takes 5 days at a minimum for the production of dental prosthesis with both stability and esthetics. 5. Every Saturday afternoon, Sunday and national holiday must be free. 6. Bonus must be paid 600% a year at a minimum. The system of retirement allowance should be active. All dental technicians ought to be affliated with their labor union and medica insurance. 7. Such dental restoration as porcelain and crown and bridge prosthesis must by increased to a degree between 30% and 50% at a minimum and the reduction system of charge for a dental technique has to be abolished. 8. The general working conditions of dental laboratory, especially pay and working hour must be improved. 9. To advance the service improvement of dental treatment and the banishment of illegal one, the medical insurance of crown and bridge prosthesis must be generally practised. 10. Ill case of the staff cull:lloyulent of dental laboratory, minimem wage system must be observed. 11. Directing dentist system on the ertablisment of dental laboratory must be abelished or wholly improved.

• KIPS Transactions on Computer and Communication Systems
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• v.3 no.5
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• pp.155-162
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• 2014

We proposed a 2 level tree based cluster based routing protocol for mobile ad hoc networks. it is our crucial goal to establish improved clustering's structure in order to extend average node life-time and elevate the average packet delivery ratio. Because of insufficient wireless resources and energy, the method to form and manage clusters is useful for increasing network stability. but cluster-head fulfills roles as a host and a router in clustering protocol of Ad hoc networks environment. Therefore energy exhaustion of cluster-head causes communication interruption phenomenon. Effective management of cluster-head is key-point which determines the entire network performance. The scheme focuses on improving the performance the life time of the network and throughput through the management of cluster-heads and its neighbor nodes. In simulation, we demonstrated that it would obtain averagely better 17% performance than LS2RP.

• Journal of Digital Contents Society
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• v.11 no.1
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• pp.91-97
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• 2010

Flash memory has been used by many digital devices for data storage, exploiting the advantages of non-volatility, low power, stability, and so on, with the help of high integrity, large capacity, and low price. As the fast growing popularity of flash memory, the density of it increases so significantly that its entire address mapping table becomes too big to be stored in SRAM. This paper proposes the associated page address cache with an efficient table management scheme for hybrid flash translation layer mapping. For this purpose, all tables are integrated into a map block containing entire physical page tables. Simulation results show that the proposed scheme can save the extra memory areas and decrease the searching time with less 2.5% of miss ratio on PC workload and can decrease the write overhead by performing write operation 33% out of total writes requested.

• Korean Journal of Construction Engineering and Management
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• v.16 no.6
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• pp.84-91
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• 2015

Project Financing (PF) is a financing method, executed based upon the projected profitability from a project itself instead of relying on the credit rating of project sponsors or any type of collateral. However, most financial institutions of Korea lacks the long term profitability assessment capability, and they prefer to acquire credit reinforcement from the construction companies in the form of the guarantor or debt argument commitments. As a result, PF contingent liabilities as an indirect debt, are burdened to the construction companies. Even though the PF contingent liabilities are not supposed to be part of the financial statements, they became a mandatory disclosure items since 2009. In this study, PF contingent liabilities were studied to indicate how they were correlated with construction firms' financial ratios. Construction firms were grouped by their credit rating and each group was compared in order to analyze PF contingent liabilities' impact on the financial condition of the company in terms of liquidity, liability, and stability.

• Journal of the Korean institute of surface engineering
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• v.55 no.2
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• pp.120-132
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• 2022

In the non-cyanide-based electroless Au plating solution using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent, analysis of each component constituting the plating solution is essential for the analysis of the reaction mechanism. And component analysis in the plating solution is important for monitoring component changes in the plating process and optimizing the management method. Capillary Electrophoresis (CE) method is rapid, sensitive and quantitative and could be readily applied to analysis of Auⁿ⁺ ion, complexing agent and reducing agent in electroless Au plating solution. In this study, the capillary electrophoresis method was used to analyze each component in the electroless Au plating solution in order to elucidate the complex bonding form and the plating mechanism of the non-cyanide-based electroless Au plating bath. The purpose of this study was to establish data for optimizing the monitoring and management method of plating solution components to improve the uniformity of precipitation and stability. As a result, it was confirmed that the analysis of thiomalic acid as a complexing agent and Auⁿ⁺ ions and the analysis of aminoethanethiol as a reducing agent were possible by capillary electrophoresis. In the newly developed non-cyanide-based electroless Au plating solution, it was confirmed that Auⁿ⁺ ions exist in the form of Au⁺ having a charge of +1, and that thiomalic acid and Au⁺ are combined in a molar ratio of 2 : 1. In addition, it was confirmed that aminoethanethiol can form a complex by combining with Au⁺ ions depending on conditions as well as acting as a reducing agent.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.2
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• pp.91-99
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• 2023

Participation in power trading using surplus power is considered a business model active in the domestic energy trade market, but it is limited only if the legal requirements according to the type, capacity, and use of the facilities to be applied for are satisfied. The hydrogen residential demonstration model presented in this paper includes solar power, energy storage system (ESS), fuel cell, and water electrolysis facilities in electrical facilities for private use with low-voltage power receiving system. The concept of operations strategy for this model focuses on securing the energy self-sufficiency ratio of the entire system, securing economic feasibility through the optimal operation module installed in the energy management system (EMS), and securing the stability of the internal power balancing issue during the stand-alone mode. An electric facility configuration method of a hydrogen residential complex demonstrated to achieve this operational goal has a structure in which individual energy sources are electrically connected to the main bus, and ESS is also directly connected to the main bus instead of a renewable connection type to perform charging/discharging operation for energy balancing management in the complex. If surplus power exists after scheduling, participation in power trading through reverse transmission parallel operation can be considered to solve the energy balancing problem and ensure profitability. Consequentially, this paper reviews the legal regulations on participation in electric power trading using surplus power from hydrogen residential models that can produce and consume power, gas, and thermal energy including hybrid distributed power sources, and suggests action plans.

• Journal of the Korean Wood Science and Technology
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• v.32 no.5
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• pp.29-38
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• 2004

In this study, we investigated the thermal properties of corn-starch filled polybutylene succinate-adipate (PBS-AD) bio-composites. Thermal analysis (TA) is used to describe the analytical method for measuring the chemical property and weight loss of composite materials as a function of temperature. The thermal stability of corn-starch was lower than that of pure PBS-AD. As corn-starch loading increased, the thermal stability and degradation temperature of the bio-composites decreased and the ash content increased. It can be seen that the degree of compatibility and interfacial adhesion of the bio-composites decreased because of the increasing mixing ratio of the corn-starch. As the content of corn-starch increased, there was no significant change in the glass transition temperature (T_g) and the melting temperature (T_m) for the bio-composites. The storage modulus (E') and loss modulus (E") of the corn-starch flour filled PBS-AD bio-composites were higher than those of PBS-AD, because of the incorporation of corn-starch increased the stiffness of the bio-composites. At higher temperatures, the decreased storage modulus (E') of bio-composites was due to the increased polymer chain mobility of the matrix polymer. From these results, we can expect that corn-starch has potential as a reinforcing filler for bio-composites. Furthermore, we recommend using a coupling agent to improve the interfacial adhesion between corn-starch and biodegradable polymer.