• The Korean Journal of Pesticide Science
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• v.14 no.1
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• pp.37-48
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• 2010

The diacylhydrazine insecticides, methoxyfenozide, chromafenozide and tebufenozide are new-generation insecticides. These insecticides induce premature molting and cause the death of insects by mimicking their hormone. Also, these insecticides have already been widely used for vegetables planting in worldwide. Highperformance liquid chromatography (HPLC) is the most widely used procedure for determination of each compound residues in crops. However, simultaneous analysis method of these diacylhydrazine insecticides was not reported. The purpose of this study is to develop a simultaneous determination procedure of methoxyfenozide, chromafenozide and tebufenozide residue in crops using HPLC-UVD/MS method. These insecticide residues were extracted with acetone from representative samples of five raw products which comprised hulled rice, soybean, apple, pepper, and Chinese cabbage. The extract was diluted with saline water, and dichloromethane partition was followed to recover these insecticides from the aqueous phase. Florisil column chromatography was additionally employed for final cleanup of the extracts. The analytes were quantitated by HPLCUVD/MS, using a $C_{18}$ column. The crops were fortified with each insecticide at two levels per crop. Mean recoveries ranged from 89.0 to 104.8% in five representative agricultural commodities. The coefficients of variation were less than 3.9%. Quantitative limits of methoxyfenozide, chromafenozide and tebufenozide were 0.04 mg/kg in crop samples. A HPLC-UVD/MS with selected-ion monitoring was also provided to confirm the suspected residues. The proposed simultaneous analysis method was reproducible and sensitive enough to determine the residues of methoxyfenozide, chromafenozide and tebufenozide in agricultural commodities.

• Journal of Satellite, Information and Communications
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• v.3 no.2
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• pp.13-17
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• 2008

The conventional telemetry system of Korean low-earth orbiting satellites has certain limitations in accommodating various missions. As the payload becomes complex, it requires very complicated operational concepts in terms of telemetry. With the current design, the telemetry formats have to be rebuilt whenever new payloads or operation concepts are involved, and many constraints in operation shall be produced due to the lacks of its flexibility. As the capability and performance of a satellite have been improved, the communication structure of the satellite should be improved to gather more telemetry data. For the efficiency of data handling, it is necessary to change the grid based telemetry system in which the downlink interval and types for telemetry was limited. Comparing the fixed data map such as grid type, the packet based telemetry system can be operated as flexible and various types of packet can be designed such as the dump packet and the event packet. The sequence of the packets can be modified or newly defined to manage the massive satellite state of health data. In this paper, a new strategy for the telemetry development partially derived from PUS (Packet Utilization Standard) of European Space Agency, which provides enhanced features for the accommodation of payloads & operational requirements, is presented.

• Applied Microscopy
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• v.40 no.4
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• pp.177-183
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• 2010

A focused ion beam (FIB) system produces a beam of positive ions (usually gallium) which are heavier than electrons and can be focused by electrostatic lenses into a spot on the specimen. With its ability milling of the specimen material by 10 to 100 nm with each pass of the beam, FIB is widely adopted in materials science, semiconductor industry, and ceramics research. Recently, FIB has been increasingly employed in the field of biomedical sciences. Here we provide a brief introduction to FIB and its applications for a wide variety of biomedical research. The surface of specimen can be in situ processed and quasi-real time visualized by two beam combination of FIB and field emission scanning electron microscope (FESEM). Due to its milling process, internal structures can be exposed and analyzed: yeast cells, fungus-inoculated wheat leaf, mannitol particles in inhalation aerosols, and oyster shell. Serial blockface tomography with the system kindles 3-dimensional reconstruction researches in the realm of nervous system and life sciences. Two-beam system of FIB/FESEM is a versatile tool to be utilized in the biomedical sciences, especially in 3-dimensional reconstruction studies.

• Journal of Veterinary Clinics
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• v.28 no.2
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• pp.219-224
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• 2011

The health status of three groups of Hanwoo steers (n=157) aged 2-3 years, raised at three different altitudes (600 m, n=50; 200-400 m, n=58; plane land, n=49) and environment with more or less similar management have been evaluated through hematological, biochemical and globulin examinations in order to determine the optimum environment suitable for raising cattle while at the same time minimizing the risk of disease. Five mL of blood samples from each animal were collected by jugular veinipuncture and 2 mL was transferred to a tube containing EDTA for complete blood count (CBC) and 3 mL in lithium heparin for chemistry screening (CS) and immunoassay. Among the CBC parameters a significantly higher white blood cell count (tWBC), total red blood cell count (tRBC), hemoglobin (Hb) and packed cell volume (PCV) were noticed in the high altitude groups, whereas those were lower in the plane land group. In the CS parameters higher levels of aspartate aminotransferase (AST), creatinine, lactate dehydrogenase (LDH) and total bilirubin (TBL) were found in the plane land group, whereas those were lower in the high altitude groups. The total protein (significantly) and globulins were higher in the 600 m group. The results of this study revealed that the overall health status of the Hanwoo cattle based on the hemato-biochemical indices was superior in the highest altitude and inferior in the plane land group but all the parameters were within the reference range in all the groups. Therefore, for recommendation of a suitable environment at an appropriate altitude for raising cattle there need to be further studied along with the hemato-biochemical parameters; considering, breeding, feeding, management, marketing, waste disposal and other factors.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.669-685
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• 2012

This study was carried out to investigate the nutrient value and yield response of corn, barley, and sudangrass by the application of anaerobic liquid fertilizer in two tidal land soil in order to design the resource recycling agricultural system between livestock and forage crop cultivation in a environment friendly agricultural region. Forage crop yields at reclaimed tidal soil during were at the level of 64~76% comparing with forage crop yields at upland soil in the cropping system of corn, barley, and sudangrass. And yields of forage crops were in the order of barley > corn > sudangrass in the cultivated cropping system for 2 year. Relative feed values (RFVs) of forage crops were 88%~106% for corn, 90%~111% for barley, and 91%~113% for sudangrass, and the carrying capacity of beef cattle (Hanwoo) was 5.8~8.6 head/year/ha for the corn-barley cropping system of one year, and 4.8~6.7 head/year/ha for the barley-sudangrass cropping system of one year. Also, carrying capacity of beef cattle (Hanwoo) was highest in the application level of anaerobic liquid fertilizer 200%.

• Journal of the Korean Vacuum Society
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• v.11 no.3
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• pp.151-158
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• 2002

Fabricated were ultra-shallow $p^+-n$ junctions on n-type Si(100) substrates using decaborane $(B_{10}H_{14})$ ion implantation. Decaborane ions were implanted at the acceleration voltages of 5 kV to 10 kV and at the dosages of $1\times10^{12}\textrm{cm}^2$.The implanted specimens were annealed at $800^{\circ}C$, $900^{\circ}C$ and $1000^{\circ}C$ for 10 s in $N_2$ atmosphere through a rapid thermal process. From the measurement of the implantation-induced damages through $2MeV^4 He^{2+}$ channeling spectra, the implanted specimen at the acceleration voltage of 15 kV showed higher backscattering yield than those of the bare n-type Si wafer and the implanted specimens at 5 kV and 10 kV. From the channeling spectra, the calculated thicknesses of amorphous layers induced by the ioin implantation at the acceleration voltages of 5 kV, 10 kV and 15 kV were 1.9 nm, 2.5 nm and 4.3 nm, respectively. After annealing at $800^{\circ}C$ for 10 s in $N_2$ atmosphere, most implantation-induced damages of the specimens implanted at the acceleration voltage of 10 kV were recovered and they exhibited the same channeling yield as the bare Si wafer. In this case, the calculated thickness of the amorphous layer was 0.98 nm. Hall measurements and sheet resistance measurements showed that the dopant activation increased with implantation energy, ion dosage and annealing temperature. From the current-voltage measurement, it is observed that leakage current density is decreased with the increase of annealing temperature and implantation energy.

• Proceedings of the KWS Conference
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• 2009.11a
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• pp.43-43
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• 2009

단련용 다결정 Ni기 초내열합금은 우수한 가공성, 내산화성, 고온특성 등으로 가스터빈 연소기, 디스크, 증기발생기 전열관 등 발전용 고온부품 소재에 널리 적용되고 있다. 최근 발전설비의 고효율화를 꾀하기 위해 작동 온도를 현격히 증가시키는 기술방향으로 발전하고 있고, 소재측면에서는 기존의 초내열합금 대비 고기능성을 확보할 수 있는 차세대 Ni기 초내열합금 개발이 유럽, 미국, 일본, 중국 등을 중심으로 활발히 이루어지고 있다. 이러한 소재의 고온강도 (온도수용성)를 향상시키기 위해서는 통상 규칙격자 금속간화합물인 $Ni_3(Al,Ti)-{\gamma}'$상의 분율을 증가시킬 수 있지만, ${\gamma}'$상분율이 증가할 경우 용접 및 후열처리 동안 용접열영향부 (HAZ)에서 액화균열이 발생할 가능성이 높아진다. 결정립계를 따라 발생하는 HAZ 액화균열은 입계특성에 의해 크게 영향을 받을 것으로 판단된다. 한편, 본 연구자들은 최근 입계 serration 현상을 단련용 합금에 도입시키는 특별한 열처리를 이론적 접근법을 통해 개발하였다. 형성된 파형입계는 결정학적인 관점에서 조밀 {111} 입계면을 갖도록 분해 (dissociation)되어 낮은 계면에너지를 갖게 됨을 확인하였으며, 입계형상 변화뿐만 아니라 탄화물 특성변화까지 유도하여 크리프 수명을 기존대비 약 40% 정도 향상시킴을 확인하였다. 이러한 직선형 입계 대비 'special boundary'로 간주되는 파형입계가 도입될 경우, HAZ 결정립크기 변화 및 액화거동에 미치는 영향을 고찰하고, 아울러 입계특성 제어가 용접성/용접부 품질 향상에 기여할 수 있는 가능성도 토의하고자 하였다. 본 연구에서는 재현 HAZ 열사이클 시험을 통해 미세구조를 정량적으로 비교하였다. 상대적으로 입계구조가 안정된 파형입계의 이동속도가 高계면 에너지를 갖는 직선형 입계보다 느려 HAZ 결정립 성장이 효과적으로 억제됨을 확인할 수 있었다. 입계 액화거동을 살펴보면, 두 시편 모두 $M_{23}C_6$, MC 등 입계탄화물 계면이 빠른 승온중 액화반응 (constitutional liquation)에 의해 입계가 액화되었으며, 이후 급냉에 의해 입계에 액상막이 존재한 흔적이 발견되었다. 최고온도별로 입계액화 폭/비율을 정량적으로 비교한 결과, 파형입계가 직선입계 대비 대체로 낮음을 확인할 수 있었으며, 때때로 액화되지 않고 잔존하는 입계 탄화물이 관찰되었다. 재현 HAZ 미세조직을 통해 Hot ductility 시험 결과를 유추하자면, 파형입계가 직선입계 보다 좁은 취성온도영역 (Brittle Temperature Range)을 나타낼 것으로 예상되어, 입계특성제어에 의해 Ni기 초내열합금의 용접성을 향상 가능성을 확인하였다.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.236-241
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• 2013

Introduction of rye living mulch in soybean production is important for labor-saving and reduction of herbicide usage for weeding by weed suppression and for soil conservation by mulching of rye. Soybean and rye were row-planted and broadcasted simultaneously at different planting times (May 15, May 25, June 5) and row widths (35 and 70 cm) in 2010, different soybean cultivars (Daepoong, Singi) and planting times (May 15 and June 1) in 2011, respectively, and investigated weed occurrence, early growth and yield of soybean. Acalypha australis, which is known to herbicide-resistant weed, could be controlled ecologically by rye living mulch. Occurrence of Acalypha australis was controlled effectively also by mixture of alachlor and linulon at no mulch in 2011. Early growth amount of soybean plant per area was increased by narrow row width (35 cm) at rye living mulch, which was helpful in the control of weeds, but grain yield of soybean with narrow row was decreased compared to conventional row width (70 cm) at the planting in early June. It is concluded that soybean planting as row width 70 cm in early June is proper at simultaneous planting with rye.

• Journal of Internet Computing and Services
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• v.7 no.4
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• pp.115-122
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• 2006

The purpose of this paper is to suggest the improving plans about the system as searching an effective managing devices for NEIS with analysis of managing condition. For the plans, questionnaire was performed in the five sections to primary and secondary school teachers. Those were recognition about C/S, Introduction and conductive processing of NEIS, Satisfaction of specific task on school affairs and educational matters, its function, efficiency and security as well as technical problem. Those were recognition about C/S, Introduction and conductive processing of NEIS, Satisfaction of specific task on school affairs and educational matters, its function, efficiency and security as well as technical problem. The results are following: First. in spite of satisfaction with function of C/S, it have been some problems such as frequent patch and down of server. Secondly, although the introduction of NEIS was done in hurry without gathering teachers' opinions and sufficient research of system, it has been expected to settle down normally with correction and security. Thirdly, positive reaction was generally showed in research on satisfaction of specific task for school affairs and educational matters. Fourthly, most of teachers have known the functions of NEIS and recognized its convenience. Although they has not thought it reduced their work, they have realized it's convenient for dealing with statistics. Lastly, they think of NEIS as the essential system for the age of information, in spite of problems such as reveal of personal data and security. Therefore, we should keep eyes to problem of an invasion of human right. In addition, study deep into NEIS should be conducted with consistent security for the system. In order to it. technical and legal system should be carried out side by side.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.308-314
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• 1992

To examine the characteristics of anti-complementary compounds from Arecae Pericarpium (the pericarps of Areca catechu) which showed the highest activity during our screening procedures, the extraction and purification were performed. AC-1 fraction from Arecae Pericarpium was purified by hot water extraction, methanol reflux, ethanol precipitation, dialysis and lyophilization. This compound had total sugar 48.2%, uronic acid 14.6% and protein 36.8%. Rhamnose, arabinose, mannose and galactose were found in sugar components. By cetavlon (cetyltrimethylammonium bromide) treatment AC-1 was fractionated to AC-2, AC-3 and AC-4. Among them, AC-2 showed the highest activity and yield. By periodate oxidation, AC-2 was deactivated, but had no change in activity by pronase digestion. Moreover active fractions, AC-2-IIIa and AC-2-IIIc isolated from AC-2 by two successive column chromatography using DEAE-Toyopearl $650C(Cl^-form)$ and Sephadex G-100. AC-2-IIIa was mainly made up of rhamnose, mannose, galactose and glucose, and AC-2-IIIc, mannose, galactose and glucose. These both polysaccharides were identified as homogeneous by gel filtration of Sepharose CL-4B and electrophoresis, and molecular weights of them were 120,000 and 15,000, respectively.