• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2003.11a
• /
• pp.152-157
• /
• 2003

This study represents the newly advanced formulation of hydraulic fluids for extended drain interval and introduces the performance results of used oil samples from various excavators. The used oil samples, in this paper show that there is a sharp change in viscosity drop and moderate additive depletion when viscosity index of hydraulic oil is very high. For the extension of hydraulic fluid life, it is necessary to improve the stability of viscosity and oxidation. New target properties from the used oil analysis were proposed for extended life. Performance of newly developed hydraulic oil based on used oil analysis is compared with previously used one. The properties of new formulation are the viscosity index of 140 and improved thermal stability consists of VHVI base oil. Field test results showed the possibility of extension of fluid life. Additionally, for development of high performance product, new required properties and performances were discussed.

• Journal of Agricultural Extension & Community Development
• /
• v.25 no.3
• /
• pp.149-160
• /
• 2018

This study aimed to analyze the replacement investment of the diesel fuel system with the pallet fuel system in the Korean farming sector. Equivalent annual annuity approach was used to resolve a discrepancy of useful life in capital goods and to facilitate investment analyses in an independent perspective. Data was obtained from previous studies on economic analysis of greenhouse tomato, paprika and cucumber. Results showed that the replacement with the pallet fuel system was acceptable irrespective of the remaining period of useful life for the diesel fuel system. In addition, sensitivity analysis with government support level, repair cost, and light and heat energy cost show ed robustness in the possibility of replacement with the pallet fuel system while the speed of replacement was accelerated with an increase in the amount of diesel fuel used and price of diesel fuel, and a decrease in price of the pallet fuel. The result implied that the replacement investment rather than a new investment was appropriate for existing greenhouse farmers and the pallet fuel system was acceptable to replace existing diesel fuel system in producing greenhouse tomato, paprika and cucumber.

• Geomechanics and Engineering
• /
• v.12 no.2
• /
• pp.257-267
• /
• 2017

This paper presents laboratory investigation of stabilization of subgrade soil. One type of soil and three types of stabilizers i.e., hydrated lime, class F fly ash and polypropylene fibres are selected in the study. Atterberg limit, compaction, california bearing ratio (CBR), unconfined compressive strength and triaxial shear strength tests are conducted on unstabilized and stabilized soil for varying percentage of stabilizers to analyze the effect of stabilizers on the properties of soil. Vertical compressive strains at the top of unstabilized and stabilized subgrade soil were found out by elasto-plastic finite element analysis using commercial software ANSYS. Strategy for design of optimum pavement section was based on extension in service life (TBR) and reduction in layer thickness (LTR). Extension in service life of stabilized subgrade soil is 6.49, 4.37 and 3.26 times more due to lime, fly ash and fibre stabilization respectively. For a given service life of the pavement, there is considerable reduction in layer thicknesses due to stabilization. It helps in reduction in construction cost of pavement and saving in natural resources as well.

• Journal of Agricultural Extension & Community Development
• /
• v.26 no.1
• /
• pp.1-15
• /
• 2019

The purpose of this study is to analyze the learning tendency of rural residents participating in lifelong education. The analysis data were analyzed using a polynomial model for 3,685 people using raw materials from a lifetime education survey. According to the analysis, participants in rural residents prefer small study groups. They were also approached on a practical level, such as life-help or self-realization. And the participating education programs were highly involved in vocational non-formal education. Based on the workings of personal backgrounds, participation of people with lower income and lower educational backgrounds is more active than in urban areas. In addition, the effect of improving the quality of life through lifelong education was shown in the order of big cities, small cities, rural areas. These results suggest that ways to improve the quality of life through lifelong education are not suitable as a means to maintain rural population.

• Journal of Families and Better Life
• /
• v.19 no.1
• /
• pp.221-234
• /
• 2001

The purpose of this study was to develop the family life planning program for sound family. The program consisted of 3 sessions : to perceive the importance of life planning, to approach the way how to life planning, to practice life planning of ones own. After a primary education, the program has adjusted 2 sessions : to perceive the importance life planning and how to do, to practice life planning of ones own. In conclusion, it is possible to adjust this program depends on circumstances. This program will be used one of the extension services for the family. And the government should be support these programs politically, especially the low-income bracket.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.12 no.2
• /
• pp.63-67
• /
• 2006

Suppressor of cytokine signaling (SOCS) is known to playa key role as a negative feedback regulator in JAK/STAT signaling cascade in innate immunity. Our laboratory has recently been interested in elucidating the interactions between Spodoptera exigua (Se) and SeNPV. This context leads us to clone and characterize SeSOCS that may have important functions in response to SeNPV infection. Using the RT-PCR and TA cloning approach, we found a partial fragment (416 bp) of SeSOCS. Blast search and multiple alignment data showed that it has a homology to various insects such as Anopheles gambiae (78%), Aedes aegypti (75%), Drosophila melanogastar (77%), Mus musculus (69%), and Homo sapiens (69%). Temporal induction patterns of SeSOCS were analysed after being immune-challenged with either NPV or laminarin. It showed that the level of SeSOCS mRNA was strongly induced in a biphasic manner in response to SeNPV and laminarin, respectively. It seems that SOCS, a negative regulator of JAK/STAT signaling system is also present in S. exigua and may playa role in innate immunity albeit its precise role should be further elucidated at the molecular and cellular level in the early phase of SeNPV infection in larvae.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.5 no.3
• /
• pp.239-246
• /
• 2017

RC(Reinforced Concrete) structures can keep their performance during intended service life through initial service life and extension of the life through repairs. In the deterministic repairing method, cost and the related $CO_2$ emission increase with step-shaped escalation, however continuous results can be obtained through probabilistic repairing technique, and this is capable of reducing $CO_2$ emission through $CO_2$ absorption. In the work, repairing timing and $CO_2$ emission/absorption are evaluated based on the different methods like deterministic and probabilistic manner. The probabilistic technique considering $CO_2$ absorption with carbonation progress is evaluated to be very effective to reduction of $CO_2$ emission through extension of initial and additional service life due to repairs. When the variations of the service life from initial construction and repair material can be determined, the proposed technique can contribute to reduction of cost and $CO_2$ with decreasing repairing number.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.2
• /
• pp.281-285
• /
• 2008

Die hobbing is one of the dieblock manufacturing methods of cold forging die, which makes the upper side of dieblock indented using master punch, hobb to produce impression not using cutting work. SKD11, alloy tool steel was used as the material of dieblock and stainless sheet metal was used as product material in cold forging work. The life span of the die was 6,000 strokes. In this research, the material of dieblock was changed into SKH51, the high speed tool steel and the product material was S45C, the carbon steel in the cold forging work. The life span of the die was 21,000 strokes, which is 350% of the life span of the die using the former method.

• Journal of Agricultural Extension & Community Development
• /
• v.10 no.2
• /
• pp.181-192
• /
• 2003

With emphasis on environmentally safe and sustainable and economically sound and oriented to consumer, this study intends to assess the consumer's cognition and attitudes for safe food distribution, to investigate the supplying system of the organic farm products, to survey the consumer and life cooperatives dealing with organic farm products, and to draw some implications toward environment- and consumer-oriented agriculture. Related literatures and available documents were reviewed to conceptualize the environmental-and consumer-oriented agriculture and consumer and life cooperatives, to grasp the nationwide status of such alternative agriculture and consumer cooperatives, and investigate the consumers' cognition and attitude. In order to investigate the consumers' needs for organic farm products and to grasp the active consumer and life cooperatives dealing with organic farm products, questionnaire method and non-structured interview were applied. The environment-and consumer-oriented agriculture refers hero to the farming system in which any farm food and other living products giving no harm to human and livestock health and catering the consumers' need. The consumer and life cooperatives is consumer's group buying and selling organic farm products organized in the cooperative system with which any consumer can be affiliated to buy organic farm products safely and reasonably.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.53 no.spc
• /
• pp.72-77
• /
• 2008

This study was carried out to determine the response of the rice yield and grain quality by rice leaf folder (RLF, Cnaphalocrocis medinalis G.) and identify the damages caused by different transplanting dates, nitrogen amounts and chlorophyll amounts (SPAD value) of rice leaf. As the damage degree of RLF was getting severer, the ripened grain rate and 1000-grain weight were decreased and due to the increasing of chalky rice rate the rate of head rice was reduced. Therefore, the yield of head rice was decreased by 36% in heavily damaged rice plant. Among the physicochemical characteristics, protein content of rice grain was increased but amylose content was reduced, consequently, the palatability was deteriorated in heavily damaged rice by RLF. The degree of damage of RLF was getting serious as transplanting date was delayed and as the amount of nitrogen was increased. In the relationship between the SPAD value and the damage degree of RLF, as the SPAD value was increased by nitrogen fertilizing, the damage degree was also increased exponential functionally.