• Title/Summary/Keyword: Trap System

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A study on the stability of a crab trap fishing boat with water tank experiment (수조 실험에 의한 게 통발 어선의 복원성에 관한 연구)

  • Lee, A-Reum;Kang, Il-Kwon;Jo, Hyo-Jae
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.45 no.4
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    • pp.267-275
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    • 2009
  • According to the recent statistics of marine casualties in Korea, fishing boats are more likely to be ended in the casualties, and small fishing boats especially cause much more accidents in sinking and capsizing than any other big vessels. These casualties were mainly produced from the ignorance on the lack of own ship stability. From this view, this study aims to analyze the characteristics of stability on the crab trap fishing boat receiving transverse wave by means of carrying out the water tank test. The rolling angle of the model ship was affected largely with the displacement and the wave period of it, and the trends were shown that the magnitude of the angle was proportional to the displacement, but inversely to the wave period. And the wave height had effect on the rolling angle just in the specific range of the wave period. The force of steady wind didn't have influence on the rolling variation significantly.

Determination of Methylmercury in Biological Samples Using Dithizone Extraction Method Followed by Purge & Trap GC-MS

  • Lee, Jung-Sub;Ryu, Yoon-Jung;Park, Jae-Sung;Jeon, Sung-Hwan;Kim, Sam-Cwan;Kim, Young-Hee
    • Bulletin of the Korean Chemical Society
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    • v.28 no.12
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    • pp.2293-2298
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    • 2007
  • In this study, a dithizone extraction technique involving purge & trap GC-MS was developed for the determination of methylmercury in biological samples, especially blood and fish. After alkaline digestion, methylmercury in biological samples was extracted into dithizone and back-extracted into aqueous sulfide solution. The extracted methylmercury was converted to the volatile ethyl derivative, purged and trapped onto a solid-phase collection medium, and then introduced into the GC-MS system. The determined MDLs of the established method were 0.9 ng·g?1 for biological samples and its accuracy and precision were found to be 93% and 3.8%, respectively. The method was validated by analysis of CRMs such as SRM 966, BCR 463 and IAEA 407 and all analytical results were within certified ranges with average RSDs of less than 6%. The analytical results of field-sampled fish also showed that the method can be successfully used as an alternative for commonly used distillation method followed by GC-CVAFS detection.

Design of Web-Based Home Gateway Management System using SSL (SSL을 이용한 웹 기반 홈 게이트웨이 관리 시스템의 설계)

  • 황태인;박광로;윤병우;조강홍;정진욱
    • Convergence Security Journal
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    • v.2 no.2
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    • pp.189-198
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    • 2002
  • In this paper, we have designed the Web_based Home Gateway Management System using SSL, which can manage subscribers using Home Gateway device in home networking technology. To manage Home Gateway devices with SNMP, management elements are classified into system. performance. fault functional area based on MIB objects from Home Gateway devices MIB. System analysis provides configuration information of each Home Gateway, and Performance analysis provides device's traffic information and state. And fault analysis provides fault logging for the unexpected events and trap message from devices. HGMS uses SSL (Secure Socket Layer) to enforce the security of communication which is between server and client, and it improved the stability of HGMS.

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The Performances of Sediment Trap for Reducing Water Pollutants and Soil Loss from Rainfall Runoff in Cropland (농경지 토양유실 및 수질오염물질 유출에 대한 침사구 조성 효과)

  • Park, Se-In;Park, Hyun-Jin;Kim, Han-Yong
    • Korean Journal of Environmental Agriculture
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    • v.38 no.4
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    • pp.307-313
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    • 2019
  • BACKGROUND: An intensive farming system may be of the most important source for agricultural non-point source (NPS) pollution, which is a major concern for agricultural water management in South Korea. Various management practices have therefore been applied to reduce NPS loads from upland fields. This study presents performances of sediment trap for reducing NPS and soil loss from rainfall runoff in cropland. METHODS AND RESULTS: In 2018 and 2019, three sediment traps (L1.5 m × W1.0 m × D0.5 m = 0.75 ㎥) and their controls were established in the end of sloped (ca. 3%) upland field planted with maize crops. Over the seasons, runoff water was monitored, collected, and analyzed at every runoff. Soils deposited in sediment traps were collected and weighed at the season end. Sediment traps reduced runoff amount (p<0.05) and NPS concentrations, though the decreased NPS concentrations were not always statistically significant. In addition, sediment traps had a significant prevention effect on soil loss from rainfall runoff in a sloped cropland. CONCLUSION: The results suggest that the sediment trap could be a powerful and the best management practice to reduce NPS pollution and soil loss in a sloped upland field.

Determination of Mequitazine in Human Plasma by Gas-Chro-matography/Mass Spectrometry with Ion-Trap Detector and Its Pharmacokinetics after Oral Administration to Volunteers

  • Kwon Oh-Seung;Kim Hye-Jung;Pyo Heesoo;Chung Suk-Jae;Chung Youn Bok
    • Archives of Pharmacal Research
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    • v.28 no.10
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    • pp.1190-1195
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    • 2005
  • The objective of this study was to develop an assay for mequitazine (MQZ) for the study of the bioavailability of the drug in human subjects. Using one mL of human plasma, the pH of the sample was adjusted and MQZ in the aqueous phase extracted with hexane; the organic layer was then evaporated to dryness, reconstituted and an aliquot introduced to a gas chromatograph/mass spectrometer (GC/MS) system with ion-trap detector. Inter- and intra-day precision of the assay were less than 15.1 and $17.7{\%}$, respectively; Inter- and intra-day accuracy were less than 8.91 and $18.6{\%}$, respectively. The limit of quantification for the current assay was set at 1 ng/mL. To determine whether the current assay is applicable in a pharmacokinetic study for MQZ in human, oral formulation containing 10 mg MQZ was administered to healthy male subjects and blood samples collected. The current assay was able to quantify MQZ levels in most of the samples. The maximum concentration ($C_{max}$ was 8.5 ng/mL, which was obtained at 10.1 h, with mean half-life of approximately 45.5 h. Under the current sampling protocol, the ratio of $AUC_{t{\rightarrow}last}$ to $AUC_{t{\rightarrow}{\infty}}$ was $934{\%}$, indicating that the blood collection time of 216 h is reasonable for MQZ. Therefore, these observations indicate that an assay for MQZ in human plasma is developed by using GC/MS with ion-trap detector and validated for the study of pharmacokinetics of single oral dose of 10 mg MQZ, and that the current study design for the bioavailability study is adequate for the drug.

Electrical characteristics of SiC thin film charge trap memory with barrier engineered tunnel layer

  • Han, Dong-Seok;Lee, Dong-Uk;Lee, Hyo-Jun;Kim, Eun-Kyu;You, Hee-Wook;Cho, Won-Ju
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.255-255
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    • 2010
  • Recently, nonvolatile memories (NVM) of various types have been researched to improve the electrical performance such as program/erase voltages, speed and retention times. Also, the charge trap memory is a strong candidate to realize the ultra dense 20-nm scale NVM. Furthermore, the high charge efficiency and the thermal stability of SiC nanocrystals NVM with single $SiO_2$ tunnel barrier have been reported. [1-2] In this study, the SiC charge trap NVM was fabricated and electrical properties were characterized. The 100-nm thick Poly-Si layer was deposited to confined source/drain region by using low-pressure chemical vapor deposition (LP-CVD). After etching and lithography process for fabricate the gate region, the $Si_3N_4/SiO_2/Si_3N_4$ (NON) and $SiO_2/Si_3N_4/SiO_2$ (ONO) barrier engineered tunnel layer were deposited by using LP-CVD. The equivalent oxide thickness of NON and ONO tunnel layer are 5.2 nm and 5.6 nm, respectively. By using ultra-high vacuum magnetron sputtering with base pressure 3x10-10 Torr, the 2-nm SiC and 20-nm $SiO_2$ were successively deposited on ONO and NON tunnel layers. Finally, after deposited 200-nm thick Al layer, the source, drain and gate areas were defined by using reactive-ion etching and photolithography. The lengths of squire gate are $2\;{\mu}m$, $5\;{\mu}m$ and $10\;{\mu}m$. The electrical properties of devices were measured by using a HP 4156A precision semiconductor parameter analyzer, E4980A LCR capacitor meter and an Agilent 81104A pulse pattern generator system. The electrical characteristics such as the memory effect, program/erase speeds, operation voltages, and retention time of SiC charge trap memory device with barrier engineered tunnel layer will be discussed.

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Characterizations of a Cold Trap System for the Process Stabilization of Al2O3 by ALD Equipment (ALD 장비의 Al2O3 공정 안정화를 위한 저온 트랩 장치의 특성 평가)

  • Yong Hyeok Seo;Won Woo Lee;In Hwan Kim;Ji Eun Han;Yeon Ju Lee;Che Hoo Cho;Yongmin Jeon;Eou-Sik Cho;Sang Jik Kwon
    • Journal of the Semiconductor & Display Technology
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    • v.23 no.1
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    • pp.92-96
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    • 2024
  • The application of the technology for forming Al2O3 thin films using ALD(atomic layer deposition) method is rapidly increasing in the semiconductor and display fields. In order to increase the efficiency of the ALD process in a mass production line, metallic by-products generated from the ALD process chamber must be effectively collected. By collecting by-products flowing out of the chamber with a cold trap device before they go to the vacuum pump, damage to the vacuum pump can be prevented and the work room can be maintained stably, resulting in increased process flow rate. In this study, a cold trap was installed between the ALD process chamber and the dry pump to measure and analyze by-products generated during the Al2O3 thin film deposition process. As a result, it was confirmed that Al and O elements were discharged, and the collection forms were two types: bulk and powder. And the binding energy peaked at 73.7 ~ 74.3 eV, the binding energy of Al 2p, and 530.7 eV, the binding energy of O 1s, indicating that the binding structure was Al-O.

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The Experimental Research of LNT for 3L-DME Engine (3리터급 DME 엔진용 LNT 후처리 장치 연구)

  • Jang, Jinyoung;Lee, Youngjae;Pyo, Youngduk;Cho, Chongpyo;Woo, Youngmin
    • Transactions of the Korean Society of Automotive Engineers
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    • v.21 no.6
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    • pp.117-122
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    • 2013
  • This study is aimed to develop LNT(Lean NOx Trap) aftertreatment system for DME engine. Modified DME engine, which was changed from diesel to current DME engine, is used for this research and is equipped with common rail type injector and fuel supplying system. LNT system has reductant injector. DME is also used as reduction agent. For this research, reduction agent injection time width and interval were varied. And also, swirler was used to improve homogeneity of reducing agent in exhaust pipe. The reduction rate of NOx by LNT was increased by longer injection width, short interval and swirler. The maximum diminution of NOx by LNT was over 85%.