• Korean journal of applied entomology
• /
• v.17 no.2 s.35
• /
• pp.115-123
• /
• 1978

Present status on the pesticides production, supply, manufacture and pests control in Korea are summarized. The data in the past several years (1971-76) are analyzed to find out the problems and solutions for the further development of plant protection and pesticide industry in Korea. Since the acreages of crop plantation and the quantities of pesticides uses are already near to the stage of plateau, pesticide formulation with imported technical grade should be modified by local synthesis with imported quality. The government pesticides management act and regulations must be modernized urgently in connection with the synthesis. formulation, tests, registration, quality control. price and supply system as well as the safety use of pesticides. Recommendation concerning acceptable daily intakes(ADI) and residue limits must be established for the strengthning pesticide safety use and plant protection activities as soon as possible. The use of fungicide-insectide mixture in dust formulation must be authorized and practiced immediately for the labor saving and one-hit cooperative mass control of rice disease and insect pests, especially. At present, serious considerations on pesticide safety use and integrated pest control are strongly urged to help the farmers, to save the industries and to keep the nature as it is required.

• Journal of Korea Spatial Information System Society
• /
• v.9 no.2
• /
• pp.55-66
• /
• 2007

There has been increasing concerns regarding marine mineral resources as the land energy resources has been depleting from worldwide energy crisis. Also, all the coastal countries around the world are getting into the high competition as EEZ implemented to widen each country's marine autonomy. Especially, the adoption of EEZ in UN's marine regulation agreement at the January of 1996 has aggravated conflicts among coastal countries and eventually resulted in critical agenda to determine the boundaries of EEZ among such countries. It is imperative for us to have negotiation with neighboring countries to determine the boundaries of EEZ. For the preparation of such negotiation, it is essential to have data such as mineral distribution, deep-sea geology, related agreement and marine laws, etc. Therefore, this study mainly concentrates on analyzing existing data of resources exploration and establishing standards for each type of data and manipulating data based on such standards, thereby building a database for more efficient management of EEZ data from marine resources survey. MRIS has also been developed to diversely analyze and visualize graphic and attribute data considering data usage and inter-relationship in the database. This system can provide various spatial analysis and spatial searching techniques to enable easier comparison of cost-benefit analysis and data provision of any area in EEZ thereby facilitating major policy making. In addition, the system can support sustainable management of marine resources of EEZ regions and data supply for systematic management of national marine resources. Furthermore, this will be very useful for negotiating with neighboring countries to determine EEZ boundaries to lead more favorable results.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.10
• /
• pp.206-211
• /
• 2020

Tungsten alloys are used widely in general industrial fields, but they are difficult to cast, so products are manufactured using powder metallurgy. In this study, a mixed powder of tungsten, nickel, and iron homogenized using a ball mill was added to pure water as a solvent, and PVA as a binder was added to prepare a spray drying mixture. The mixed liquid was prepared using a spraying machine. A study was carried out to produce a granular powder that can reduce the variations between products during the molding and sintering process of the powder metallurgy method. A preliminary experiment was conducted to confirm the influence of the variables in the granulation process. Through the preliminary test results, this experiment was performed with the volume of solvent of the spray drying the mixture as an independent variable, and granular powder having a mean particle size similar to that of the existing mass-production conditions and an increased apparent density was prepared. In addition, a pilot test was conducted for the molding and sintering process. The improved granular powder reduced the characteristic variation (weight variation) of the mass-produced product.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.4
• /
• pp.653-657
• /
• 2002

The hydrolysis conditions (enzym $e_strate ratio, time and temperature) of the mixture of anchovy sauce residue (ASR) and soy sauce residue (SSR) after fermentation by Flavourzyme 500M $G^{TM}$ were optimized using response surface methodology (RSM) for pretreatment of processing functional enzyme-hydrolyzed sauce. A model equation obtained from RSM was hydrolysis ratio (%) = 28.157+1.929enzym $e_strate ratio+1.818time+2.038temperature-1.093temperatur $e^2$, whose stationary point showed saddle point. From the ridge analysis of the saddle point, the conditions producing the highest hydrolysis ratio was determined as follows: 0.49% enzym $e_strate ratio; 3.55hr hydrolysis time; 62.5$^{\circ}C$ hydrolysis temperature. Adding of SSR to the mixture of water and ASR improved sensory qualities of mixture, so it seemed that SSR has masking effects on off-flavor and taste of ASR.R.of ASR.R.

• Korean Journal of Materials Research
• /
• v.10 no.7
• /
• pp.464-470
• /
• 2000

The compacting and sintering behavior of titanium powders containing oxygen in the range of 1980~8450 ppm was examined. The powders were prepared by the hydride-dehydride (HDH) and by the deoxidation by solid state(DOSS) methods. Their compaction density ranged from 69.0% to 62.3% and decreased with the increase in the oxygen content. It was explained by the effect of oxygen on the hardness of powders. Unlike the compaction density, the oxygen content did not affect the apparent density greatly being 90.5$\pm$0.5% after sintering at $1100^{\circ}C$ for 2 hours. Their average grain size was $60\mu\textrm{m}$ and the size and distribution of pores were about the same for all cases. The hardness of sintered samples showed a linear increase with oxygen and could be expressed as VHN(sintered)= 135.5+64.3$\times$$(wt{\%}O_2)$ The exami-nation of fracture surface revealed that the ductile-brittle transition occurs at oxygen contents of 2987~5582 ppm.

• Journal of Food Hygiene and Safety
• /
• v.24 no.1
• /
• pp.19-26
• /
• 2009

This study was undertaken to analyze the hygienic problems of group food services and to predict the outbreak patterns of future food-borne diseases. A delphi survey with 20 experts identified the main causes of food-borne outbreaks in group food services as improper hygienic management of raw food materials, washing of worker's hands, dividing the spaces and unsanitary retail storage. Vibrio parahaemolyticus, Escherichia coli (EPEC), non-typhoid Salmonella serotypes, Staphylococcus aureus, Escherichia coli (ETEC), norovirus, and the hepatitis A virus all have potential to cause outbreaks of food-borne disease. We analyzed the daily food use and the possibility of food-borne outbreaks in school food services for fruits, milk, fish, pork, eggs, and meat as raw food materials, and bibimbab, soybean sprouts muchim, spinach namul, cucumber sengchae, jabchae, and pork bulgogi as prepared food items. Frozen (${\leq}\;-20^{\circ}C$) and refrigerated ($0{\sim}10^{\circ}C$) processed foods are popular items in group food services. Their storage, heating, and chemical sanitization methods are potential sources of food disease outbreaks. Our results can be applied to a well-organized hygiene control system and can be used to develop menus for preventing food-borne outbreaks.

• Journal of Welding and Joining
• /
• v.15 no.6
• /
• pp.24-31
• /
• 1997

2매의 금속을 맞대어 그 한 쪽에 접촉면과 평행하게 고주파진동을 가하면 단 시간에 접합된다. 이공정을 초음파 용접이라고 하며 그 물리적인 본질은 아직 불분명 하지만, 첫째로는 강한 마찰에 의해 금속 자유면의 산화물층이 제거되기 때문이라는 점과 둘째로는 마찰에 의해 금속 표면이 강하게 가열되어 이에 따른 연화에 의해 접합 이 된다고 하는 점이다. 그러나 이와 같이 가열된다고 하더라도 가열은 표면부에만 국한되고 다른 부분은 가열되지 않는다. 따라서 초음파용접은 냉간접합이라고도 한다. 또 가압력과 진동에 의한 힘이 동시에 작용하기 때문에 용접할 면을 미리 청정하게 할 필요는 없고 용접전의 단계에서 자연적으로 청정화가 이루어진다고 하는 사실이 간접 적으로 증명되고 있다. 초음파 용접(Ultrasonic welding)의 특징을 요약하면 고상용접 의 일종으로서 용접중에 국부적으로 고주파 진동에너지와 압력을 가하여 용접하는 방법이다. 이 때 모재를 용융시키지 않고 건전한 야금학적 결합부가 얻어진다는 데에 큰 특징이 있다. 또한 초음파용접은 다른 용접법에 비해 경제성이 매우 높고, 초음파 용접에 필요한 출력이 전기아크 용접에 필요한 출력의 5 - 10%로 충분한 경우가 많다. 초음파 용접은 통상의 방법으로는 용접하기 어려운 동종 금속이나 이종 금속의 용접에 널리 사용된다. 이 용접법은 반도체, 미세회로, 전기 접점의 형성에 대한 생산기술 로서 사용되고 있는데 소형 모터, 알루미늄 박의 가공, 알루미늄 합금의 조립 등에 이용되고 있다. 한편 최근에는 자동차, 우주항공산업 분야의 구조제 용접용으로도 채용되고 있다.출함이 바람직하다.분비되는 배설-분비 항원의 자극과 깊은 관계가 있음을 알 수 있었다.넌트 명세서를 대한 XML DTD(Document Type Definition)를 정의하고, HTML 기반 검색 방법과 XML 기반 검색 방법에 대한 컴포넌트 검색 성능을 비교한다.따라 NO 생산 및 세포독성이 증가하였고. NO 생산을 저하시키는 약제들은 활성화된 복강 대식세포 및 RAW264.7 세포에 의한 질편모충에 대한 세포독성을 현저히 감소시키는 것으로 보아 NO는 질편모충에 대한 대식세포의 숙주 방어기전에서 중요한 역할을 감당할 것으로 생각된다.nction index) 와 최대개구시 동통의 정도는 시술전과 시술 4주후간에 유의한 차이가 관찰되었다.피부온도는 검사자간에는 특정부위에 따라 다소 차이가 있을 수 있으나 일반적으로 높은 재현성을 보여줌으로서 향후 교근 및 측두근의 임상연구 평가에 피부온도조사는 도움이 되리라 사료된다. lactobacilli의 양은 peroxidase system을 함유하거나(p < 0.01) 함유하지 않은(p < 0.05) 치약을 사용한 군 모두에서 양치전에 비해 유의성있게 감소하였다. 6. 양치후 30분에 채취한 구강건조증 환자의 자극성 전타액내 S. mutans 양은 peroxida system을 함유한 세치제를 사용한 군에서 대조군에 비해 유의성있게 낮았다(p < 0.05). 7. 양치후 30분에 채취한 구강건조증 환자의 자극성 전타액내 lactobacilli양은 peroxidase system을 함유한 세치제를 사용한 군에서 대조군에 비해 상대적으로 낮게 나타났으나(p = 0.067)

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.6
• /
• pp.1-12
• /
• 2007

For the purpose of effective utilization of domestic second-grown larch as structural members, post and beam construction applying traditional construction to Japanese larch glulam members was adopted with processing by machine pre-cut method. In general, horizontal shear test by KS F 2154 is conducted to assess the horizontal shear properties of the wooden structure by post and beam construction. The frame was consisted of post and beam member with appropriate fasteners, and members have their own processed parts (notch, hole, etc.) that can be well-connected each other. The shear wall was consisted of the frame with screw-nail sheathed panel (OSB). The results of horizontal shear loading tests without vertical loads conducted on the frame and the shear wall structures, the maximum strengths were about 1.9 kN/m and about 9.7 kN/m, the shear rigidities were about 167 kN/rad, 8198 kN/rad, respectively. The strength proportion of the frame specimen was about 20% of the wall's and about 2% in initial stiffness. Nail failures are remarkable on the shear wall specimen with punching shears and shear failures. The shear load factor for the shear wall specimen by the method of Architectural Institute of Japan was 1.5, which was obtained by the bi-linear method. Loading method should be considered to obtain smooth load-deformation relationship. For the better shear performance of the structures, column base and post and beam connections and sheathed panel should be further examined as well.

• Journal of Applied Biological Chemistry
• /
• v.55 no.1
• /
• pp.55-59
• /
• 2012

We designed a new rapid detection method for volatilized formaldehyde from wood. The process was installed with volatilizing and collecting parts in an incubator. For rapid sampling of formaldehyde from wood, we pulverized the wood to sawdust, and used 0.15-2.0 mm particles for the tests. The highest sampling rate (94.8%) was obtained at 40 mL/min flow rate and $100^{\circ}C$. Under the optimized condition, we could collect the volatilized formaldehyde with good recovery rate. The developed method was applied to the monitoring of the formaldehyde from wood, and the measured concentrations were 0.7-4.6 ${\mu}g/g$ from natural wood, 5.9-12.3 ${\mu}g/g$ from preserved wood, and 5.9-211.5 ${\mu}g/g$ from chemical adhesive processed wood. From the results, we identified natural wood sawdust and chemically processed wood (medium density fiberboard, high density fiberboard, particle board) by the formaldehyde contents except preserved wood.

• Korean Journal of Food Science and Technology
• /
• v.45 no.4
• /
• pp.473-477
• /
• 2013

The aim of this study was to identify the optimal ingredient-mixing ratio of Job's-tear and wheat flour subjected to extrusion. A modified distance-based mixture design analysis was chosen for the experimental design. The results showed that the bending failure force, the a-value, and the water absorbtion index (WAI) value had no correlation with the mixture ratio of Job's-tear and wheat flour. However, the diameter of the extrudates, the L- and b-values, and the water solubility index (WSI) value were all found to be correlated to the mixture ratio. While the first three values were determined using a linear model, the WSI value was determined using a quadratic model. The diameter and color had an inverse correlation to the mixture ratio: the higher the ratio of Job's-tear to wheat flour, the lower the diameter and darker the color. The L- and b-values were found to change in accordance with the mixture ratio of Job's-tear to wheat flour. The lowest WSI value was obtained at a 40:60 ratio of Job's-tear to wheat.