• Korean Journal of Organic Agriculture
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• v.17 no.4
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• pp.567-575
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• 2009

Organic pear (Pyrus pyriforia) fruits have remarkably increased in Korea since year 2000 due to increase consumer's demand for the fruit, and the farmers are keep trying to change their cultivation system that is replaced from conventional farming to organic-base farming for the fruit. However, there is little information for the soil properties, tree nutrition, and tree growth at organic orchards in Korea. Therefore, this study was established to investigate for the chemical properties of soils and leaf and bud characteristics of a conventional and organic pear trees in experimental orchards for two years. Commercial (Sanwool, YoungHwa Co., Korea) compost was applied to the orchard soils with conventional farming systems for two years for pear trees (10 to 15 year old trees) in KyungSan, Korea. The compost application increased pH, organic matter content, cation exchange capacity (CEC), and, microbial biomass in the soil. The compost treatment also increased specific leaf weight and foliar $P_2O_5$ concentration as well as leaf and floral bud sizes.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.209-213
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• 1999

In the society of the 21\ulcorner century under multiphase media conditions, the rapidly glowing electronic media will replace the conventional paper media in a variety of areas. However, if human being still has an affinity for paper media and an instinct for hardcopy from electronic-based text or image, the new market will be created for the paper industry. To what extent the consumer choses paper media for output will depend upon the availability of functions of paper media appealing to human senses; i.e., "sensory functions of paper". As a whole, on-demand type personal as well as business communications will increase in the next century and this trend will lead certainly to a rapidly expanding "contents hardcopy market". The technological progress of the paper industry in the 21\ulcorner century depends upon the market needs for higher products quality and higher efficiency of manufacturing process as well as an endeavour to overcome constraints from forest resource, energy, and environmental issues. Under the conditions with above constraints, the paper media will be polarized into two categories; (1)paper for higher image reproduction capability for original image or text and (2)paper for lower reproduction but with higher appeals for human senses. To cope with these trends, psycho-physical analysis and a sensory engineering approach for developing new paper media is vitally required. Also newly emerged roles of paper physics in the multimedia age is pointed out associated with sensory functions of paper that are not well-understood so far.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1445-1451
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• 2011

Pneumatic valves are widely used parts that have the ability to control the air supplied to automation systems. However, if failure occurs in a pneumatic valve, it may affect the entire system and could lead to huge losses, depending on the characteristics of the system at the time of failure. Because of this significant risk and the level of consumer demand for reliability, there has been much study on ensuring the reliability of products by predicting valve lifetime distributions and degradation characteristics. In this paper, in order to determine the main factors useful for predicting the lifetime of a pneumatic valve, the scale parameter and $B_{10}$ life time value of the widely used plug-in-type pneumatic manifold valves were measured using complete observational data on the valve lifetimes. And also the property of life distribution has been distribution-suitabilityreviewed by correlation coefficients, the degradation characteristics of valve has been presented by the result of analysis through dynamic response time test and leakage test.

• Korean Journal of Medicinal Crop Science
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• v.26 no.3
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• pp.205-213
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• 2018

Background: Since the revised Ginseng Industrial Act was passed, ginseng sprouts have become a new medicinal vegetable for which there is high consumer demand. However, the existing amount of research and data on ginseng production has not kept pace with this changed reality. Methods and Results: In this study we analyzed the changes in the amounts of ginsenosides in different parts of growing ginseng sprouts during the period from when organic seedlings were planted in nursery soil until 8 weeks of cultivation had elapsed, which was when the leaves hardened. In the leaves, ginsenoside content increased 1.62 times with the panaxadiol (PD) system and 1.31 - 1.56 times with the panaxatriol (PT) system from 7 to 56 days after transplantation. During the same period, the total ginsenoside content of the stems decreased by 0.66 - 0.91 times, and those of the roots increased until the $21^{st}$ day, and then underwent steep declines. The effect of fermented press cake extract (FPCE) and tap water (TP) on the total amount of ginsenoside per plant were similar, and could be represented with the equations $y=1.4330+0.2262x-0.0008x^2$ and $y=0.9555+0.2997x-0.0031x^2$ in which y = ginsenoside content x = amount of and on the total amounts of FPCE or TP, respectively after 26.4 days, however, the difference between ginsenoside content with FPCE and TP widened. Conclusions: These results suggested that the amounts of ginsenosides in different parts of ginseng varied with the cultivation period and nutrient supply. These findings also provide fundamental data on the distribution of ginsenosides among plant parts for 2-year-old ginseng plants in the early-growth stage.

• Journal of Biosystems Engineering
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• v.40 no.3
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• pp.224-231
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• 2015

Purpose: Corn is a major commercial crop targeted for genetic modification owing to its high consumer demand as a foodstuff for humans and livestock, as well as its other industrial applications. However, the safety of genetically modified (GM) crops is controversial. Indeed, several countries have banned the importation of GM seeds that can germinate. Therefore, development of effective, convenient, and nondestructive methods to inhibit seed germination is required. Methods: This study aimed to examine the efficacy of microwave heat treatment for inhibition of germination of corn kernels and for optimization of power and exposure time required for effective aging treatment. Artificial inhibition was induced in corn kernels using microwave heat treatment. Seven power levels were examined (400, 500, 600, 700, 800, 900, and 1000 W) at each of the four exposure times (0.5, 1.0, 1.5, and 2.0 min). Results: Corn kernels could be aged effectively after heating for 0.5~1.0 min at powers greater than 800 W, with increasing efficacy observed at higher powers. Further analysis showed that the most effective inhibition of germination was observed at 1000 W for 40 s. This setting did not cause any physical damage to the corn kernels. Conclusions: Optimal inhibition of corn kernel germination was achieved using higher power for shorter times, which may be useful for industrial corn seed treatment.

• Journal of Powder Materials
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• v.23 no.4
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• pp.325-330
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• 2016

Owing to increasing demand of rare metals present in ICT products, it is necessary to promote the rare metal recycling industry from an environmental viewpoint and to prevent climate change. Despite the fact that information for toxic substances is partly indicated, a legal basis and an international standard indicating usage of rare metals is insufficient. In order to address this issue, a newly created study group of environment and climate change at the ITU (International Telecommunication Union) is doing research to develop methodologies for recycling rare metals from ICT products in an eco-friendly way. Under this group, the Republic of Korea has established two international standards related to rare metals present in ICT products. The first is 'Release of rare metal information for ICT products (ITU-T L.1100)' and the other is 'Quantitative and qualitative analysis methods for rare metals (ITU-T L.1101)'. A new proposal for recommending the provision of rare metal information through a label by manufacturers and consumer/recycling businesses has been approved recently and is supposed to be published later in 2016. Moreover, these recommendations are also being extended to IEC, ISO and other standardization organizations and a strategy to reinforce the ability for domestic standardization is being established in accordance with industrial requirements. This will promote efficient recycling of rare metals from ICT products and will help improve the domestic supply of rare metals.

• Korean Journal of Environmental Agriculture
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• v.25 no.2
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• pp.174-179
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• 2006

Chinese cabbage, Braccica campestris has long been consumed as a staple food for Koreans in various forms of fresh, salted, and fermented Kimchi. Cultivation of the crop under greenhouse has become a general practices to fulfill its off-seasonal consumer's demand. However, agricultural practices of the crop have always accompanied with heavy applications of pesticides caused by severe outbreaks of diseases and pose under warm and humid circumferences. Since dissipation patterns of pesticide residues in/on the crop under greenhouse conditions ate quite different from those in the open-air, changes of diazinon, O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphornthioate, in/on the Chinese cabbage applied by foliar spraying under greenhouse were studied. Diazinon 34% EC was applied with dilution of recommended and double dose to the crop. The shoots of crop were harvested immediately after this application and at regular intervals over a 10-day. After sample preparations, the diazinon residue was analyzed using gas chromatography equipped with electron capture detector (GC/ECD). Initially deposited amount of the chemical in/on the crop right after applications with recommended and double doses were 8.3 and 15.2 mg/kg, respectively. The residue levels after 10 days of application were 0.03 and 0.09 mg/kg with 1.3 and 1.5 days of half-life in/on the crop, respectively. In consequent 10 days of pre-harvest interval (PHI) for diazinon EC formulation in/on Chinese cabbage under greenhouse condition was fulfill maximum residue level set by Korea Food and Drug Administration (KFDA, 0.1 mg/kg).

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.2
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• pp.484-503
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• 2016

Mobile cloud computing has recently become a new paradigm for the utilization of a variety of shared mobile resources via wireless network environments. However, due to the inherent characteristics of mobile devices, a limited battery life, and a network access requirement, it is necessary for mobile servers to provide a dynamic approach for managing mobile resources efficiently in mobile cloud computing environments. Since on-demand job requests occur frequently and the number of mobile devices is drastically increased in mobile cloud computing environments, a different mobile resource management method is required to maximize the computational power. In this paper, we therefore propose a cooperative, mobile resource sharing method that considers both the inherent properties and the number of mobile devices in mobile cloud environments. The proposed method is composed of four main components: mobile resource monitor, job handler, resource handler, and results consolidator. In contrast with conventional mobile cloud computing, each mobile device under the proposed method can be either a service consumer or a service provider in the cloud. Even though each device is resource-poor when a job is processed independently, the computational power is dramatically increased under the proposed method, as the devices cooperate simultaneously for a job. Therefore, the mobile computing power throughput is dynamically increased, while the computation time for a given job is reduced. We conduct case-based experiments to validate the proposed method, whereby the feasibility of the method for the purpose of cooperative computation is shown.

• Korean Journal of Occupational Health Nursing
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• v.24 no.4
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• pp.372-380
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• 2015

Purpose: The purpose of this study was to seek ways to improve the quality of life of workers by separating workers into the low fatigue group and the severe fatigue group depending on the level of fatigue level, and analyzing and understanding the difference between quality of life and job stress according to the fatigue level. Methods: For the 'Development of Mibyeong management system which was a consumer-directed health care service', the data of job stress, fatigue and quality of life was collected from 115 workers who visited the oriental hospitals located in J city and C city from Jul, 2012 to Dec, 2012. Results: The severe fatigue group showed significantly higher job stress than the low fatigue group in physical environment (p=.004), job demand (p<.001), interpersonal conflict (p=.012), lack of reward (p=.062). The severe fatigue group showed lower degrees both in physical component summary (PCS) (p<.001) and mental component summary (MCS) (p<.001) measured by SF-12 and the quality of life (p<.001) measured by EQ5D than the lower fatigue group. A relatively strong negative correlation was found in the item of mental component summary (MCS) measured by SF-12. Conclusion: Considering our results that high fatigue level show negative impact on quality of life and job stress, we suggest to provide a variety of health promotion strategies to improve the quality of life through the prevention and relief of fatigue for workers.

• Korean Journal of Plant Resources
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• v.4 no.2
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• pp.67-74
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• 1991

Many people have a growing interest on the health result from economic improvement, various environimental pollution and stress, and unrest on the adult diseases etc.In these result, demand for the herb medicine continues to expand. Farmers of theour country have a hardship in the farm management owing to of opening and liberaliza-tion, and make strenuous efforts on the devclopment of substitute crops to overcomethese differties. Government nowadays recommends the cultivation of the economiccrops like a flowers, medicinal herbs mushroom and clean vegetables. Medicinal herbsare specially profitable among these crops because herbs are possible to culture inwaste land, disused field and slope land, and owing to need less labor and competitionthan those of other crops. The most important problem is the facts that the compli-cation of currency structure of herb medicine inflicts mucll loss to cultivators. Therefore, this study was investigated the state of herb cultivation and the facts to be imploved in currency structure of the harvested herb medicine.1 . The cultivating area and output have been gradually increased and much produc-ted in Kyoungbuk, Kangwon, Choongbuk, Cheonbuk and Cheonnam province in or-der of cultivating area 2. Collection amount of wild herb medicine is decreasig bythe reason of the varous difficulties on the collection. 3. Cultivators of medicinal herbscan make agricultural management more resonable in information exchange on theherb cultivation, purchase of seed, fertilizer, chemicals and other materials, and sell-ing of harvested herb medicine by organization of cultivator fraternity. 4 Cultivatorshave to exclude intermediary margin by the development of direct transaction andcontract cultivation with medicinal herb store, drug manufacturer, chinese meicinehospital and trading firm etc. And also, by the performing exportation with foreign consumer.