• 제목/요약/키워드: inexpensive

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저렴한 유리강화 활성탄소섬유를 이용한 건식 동시 탈황 탈질 시스템의 개발 (Preparation of the Inexpensive Fiberglass-Reinforced Activated Carbon Assemblies, and Development of Dry De-NOXSO System as Its Application)

  • 정애영;이시훈;김동표
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.1065-1068
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    • 1998
  • On the study, The activated carbon assemblies(ACA) were prepared by activation of the coated glass mate(woven type) with phenolic resin at $700^{\circ}C$ under $N_2$ after drying and curing processes. Surface of the ACA was continuously modified with $N_2$, $CO_2$ or $NH_3$ at $700^{\circ}C$ for 2 hour for comparison of adsorptive characteristics between the ACA and commercial activated carbon cloth. The ACA showed high surface areas up to $2440\;m^2/g$ when converted into the coated carbon base, and the surface was investigated by FT-IR and XPS. The basic ACA modified with $NH_3$ displayed the efficient removal capability of $SO_2$, which is 75% of that in commercial activated carbon cloth. Therefore, it has proved the applicability of ACA as an inexpensive materials for Dry de-SOX system.

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CT scan의 다평면 재구성을 하는 Dentascan 프로그램과 개인용 컴퓨터를 이용한 영상재형성과의 비교에 관한 연구 (Comparison of Image reformation Using Personal Computer with Dentascan Program)

  • 김은경
    • 치과방사선
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    • 제27권1호
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    • pp.7-16
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    • 1997
  • This study was performed to demonstrate the method of image reformation for dental implants, using a personal computer with inexpensive softwares and to compare the images reformatted using the above method with those using Dentascan software. CT axial slices of 5 mandibles of 5 volunteers from GE Highspeed Advantage(GE Medical systems, U.S.A.) were used. Personal computer used for image reformation was PowerWave 6041120 (Power Computing Co, U.S.A.) and softwares used were Osiris (Univ. Hospital of Geneva, Switzerland) and Import ACCESS V1.H Designed Access Co., U.S.A.) for importing CT images and NIH Image 1.58 (NIH, U.S.A.) for image processing. Seven images were selected among the serial reconstructed cross-sectional images produced by Dentascan(DS group). Seven resliced cross-sectional images at the same position were obtained at the personal computer(PC group). Regression analysis of the measurements of PC group was done against those of DS group. Measurements of the bone height and width at the reformed cross-sectional images using Mac-compatible computer were highly correlated with those using workstation with Dentascan software(height : r²=0.999, p<0.001, width : r²=0.991, p<0.001). So, it is considered that we can use a personal computer with inexpensive softwares for the dental implant planning, instead of the expensive software and workstation.

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Tensile strength prediction of corroded steel plates by using machine learning approach

  • Karina, Cindy N.N.;Chun, Pang-jo;Okubo, Kazuaki
    • Steel and Composite Structures
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    • 제24권5호
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    • pp.635-641
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    • 2017
  • Safety service improvement and development of efficient maintenance strategies for corroded steel structures are undeniably essential. Therefore, understanding the influence of damage caused by corrosion on the remaining load-carrying capacities such as tensile strength is required. In this study, artificial neural network (ANN) approach is proposed in order to produce a simple, accurate, and inexpensive method developed by using tensile test results, material properties and finite element method (FEM) results to train the ANN model. Initially in reproducing corroded model process, FEM was used to obtain tensile strength of artificial corroded plates, for which surface is developed by a spatial autocorrelation model. By using the corroded surface data and material properties as input data, with tensile strength as the output data, the ANN model could be trained. The accuracy of the ANN result was then verified by using leave-one-out cross-validation (LOOCV). As a result, it was confirmed that the accuracy of the ANN approach and the final output equation was developed for predicting tensile strength without tensile test results and FEM in further work. Though previous studies have been conducted, the accuracy results are still lower than the proposed ANN approach. Hence, the proposed ANN model now enables us to have a simple, rapid, and inexpensive method to predict residual tensile strength more accurately due to corrosion in steel structures.

고무 도뇨관을 이용한 간단한 수지 지혈대 (A Tunable Digital Tourniquet Using Nelaton Catheter)

  • 김상화;임영민;정성노;권호
    • Archives of Plastic Surgery
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    • 제35권6호
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    • pp.759-761
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    • 2008
  • Purpose: Surgery on digit requires a clear, bloodless field and it can be achieved by using a tourniquet. Several type of tourniquet have been used including Penrose drains and sterile glove with hemostat. We present a simple digital tourniquet using nelaton catheter, which is easily available, inexpensive, easy-to-apply, and effective for digital surgery. Methods: We made a small incision on the opposite side of an opening at the tip of nelaton catheter. Then the other tip of nelaton catheter is passed through the incision to form a ring. Nelaton catheter is placed aournd the base of the injured finger, making a tight circle to desired pressure. Results: A simple tourniquet using nelaton catheter effectively achieves a bloodless field and allows fine control of the pressure for digital surgery. Conclusion: We present a sismple digital tourniquet using nelaton catheter, which is easily available, inexpensive, tunable, and available for more than one finger.

치과 임플란트 계획시 개인용 컴퓨터를 이용한 영상재형성에 관한 연구 (Image Reformation with a Personal Computer for Dental Implant Planning)

  • Eun-Kyung Kim
    • Journal of Oral Medicine and Pain
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    • 제21권2호
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    • pp.255-264
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    • 1996
  • This study was performed to demonstrate the method of image reformation for dental implants, using a personal computer with inexpensive softwares and to compare the images reformatted using the above method with those using Dentascan software. CT axial slices of 4 mandibles of 4 volunteers from GE Highspeed Advantage(GE Medical systems, U.S.A.) were used. personal computer used for image reformation was PowerWave 604/120 (Power computing Co, U.S.A. ) and softwares used were Osiris (Univ. Hospital of Geneva, Switzerland) and ImportACLESS Vl.1 (Designed Access Co., U.S.A.) for importing CT images and NIH image 1.58 (NIH, U.S.A.) for image processing. Seven image were selected among the serial reconstructed cross-sectional images produced by Dentascan. Seven resliced cross-sectional images at the same position were obtained at the personal computer. Regression analysis of the measurements of PC group was done against those of DS group. Measurements of the bone height and width at the reformer cross-sectional images using Mac-compatible computer was highly correlated with those using workstation with Dentascan software(height : r2= 0.999, p<0.001, width : r2= 0.993, p <0.001). So, it is considered that we can use a personal computer with inexpensive software for the dental implant planning, instead of the expensive software and workstation.

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테러리즘 위협 예방과 경호정보의 역할 (Prevention of Terrorism Threat and Role of Security Intelligence in New Terrorism)

  • 백종갑;김태환
    • 한국재난정보학회 논문집
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    • 제1권1호
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    • pp.43-71
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    • 2005
  • Terrorism is the use of violence, especially murder and bombing, in order to achieve political aim or to force a government to do something. Nowadays, instrument of mass destruction are smaller, cheaper, and more readily available. Cellular phones were used as timers in the attacks in Madrid last March. Hijacking an airplane is relatively inexpensive. Finally, the information revolution provides inexpensive means of communication and organization that allow groups once restricted to local and national police jurisdictions to become global. Al Qaeda is said to have established a network in fifty or more countries. These technological and ideological trends increased both the lethality and the difficulty of managing terrorism. Because of the unprecedented scale of Al Qaeda's attacks, the focus is properly on Islamic extremists. But it would be a mistake to limit our concern solely to Islamic terrorists, for that would ignore the way that technology is putting into the hands of deviant groups and individuals' destructive capabilities that were once limited primarily to governments and armies.

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A Multiplex PCR Method for the Detection of Genetically Modified Alfalfa (Medicago sativa L.) and Analysis of Feral Alfalfa in South Korea

  • Choi, Wonkyun;Kim, Il Ryong;Lim, Hye Song;Lee, Jung Ro
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • 제1권1호
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    • pp.83-89
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    • 2020
  • Methods for detecting the presence of genetically modified (GM) crops are evolving to comply with legislation and to enhance monitoring by biotechnology companies and regulators. In order to cover a broad range of detection methods for a new GM crop, conventional multiplex PCR methods are required. Based on the genetic information on three GM alfalfa varieties (J101, J163, and KK179), which were recently approved in South Korea, we developed a fast, reliable, and highly specific multiplex polymerase chain reaction (PCR) method with basic PCR equipment and inexpensive reagents. To validate and verify the newly developed multiplex PCR method, we applied a limit of detection assay and random reference material analysis. We also monitored the unintentional environmental release of GM alfalfa in South Korea by performing the multiplex PCR analysis with 91 feral alfalfa specimens collected from 2000 to 2018. Our methodology is a sensitive, simple, quick, and inexpensive tool for detecting and identifying three GM alfalfa varieties.

Electrodeposition of Silicon from Fluorosilicic Acid Produced in Iraqi Phosphate Fertilizer Plant

  • Abbar, Ali H.;Kareem, Sameer H.;Alsaady, Fouad A.
    • Journal of Electrochemical Science and Technology
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    • 제2권3호
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    • pp.168-173
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    • 2011
  • The availability, low toxicity, and high degree of technological development make silicon the most likely material to be used in solar cells, the cost of solar cells depends entirely on cost of high purity silicon production. The present work was conducted to electrodeposite of silicon from $K_2SiF_6$, an inexpensive raw material prepared from fluorosilicic acid ($H_2SiF_6$) produced in Iraqi Fertilizer plants, and using inexpensive graphite material as cathode electrode. The preparation of potassium fluorosilicate was performed at ($60^{\circ}C$) in a three necks flask provided with a stirrer, while the electro deposition was performed at $750^{\circ}C$ in a three-electrodes configuration with melt containing in graphite pot. High purity potassium fluorosilicate (99.25%) was obtained at temperature ($60^{\circ}C$), molar ratio-KCl/$H_2SiF_6$(1.4) and agitation (600 rpm). Spongy compact deposits were obtained for silicon with purity not less than (99.97%) at cathode potential (-0.8 V vs. Pt), $K_2SiF_6$ concentration (14% mole percent) with grain size (130 ${\mu}m$) and level of impurities (Cu, Fe and Ni) less than (0.02%).

저렴한 유리강화 활성탄소섬유를 이용한 건식 동시 탈황 탈질 시스템의 개발 (Preparation of the Inexpensive Fiberglass-Reinforced Activated Carbon Assemblies, and Development of Dry De-NOXSO System as Its Application)

  • 정애영;이시훈;김동표
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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    • pp.717-720
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    • 1998
  • On the study, The activated carbon assemblies(ACA) were prepared by activation of the coated glass mat(woven type) with phenolic resin at $700^{\circ}C$ under $N_2$ after drying and curing processes. Surface of the ACA was continuously modified with $N_2$, $CO_2$ or $NH_3$ at $700^{\circ}C$ for 2 hour for comparison of adsorptive characteristics between the ACA and commercial activated carbon cloth. The ACA showed high surface areas up to $2440\;m^2/g$ when converted into the coated carbon base, and the surface was investigated by FT-IR and XPS. The basic ACA modified with $NH_3$ displayed the efficient removal capability of $SO_2$, which is 75% of that in commercial activated carbon cloth. Therefore, it has proved the applicability of ACA as an inexpensive materials for Dry de-SOX system.

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Computing-Inexpensive Matrix Model for Estimating the Threshold Voltage Variation by Workfunction Variation in High-κ/Metal-gate MOSFETs

  • Lee, Gyo Sub;Shin, Changhwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제14권1호
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    • pp.96-99
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    • 2014
  • In high-${\kappa}$/metal-gate (HK/MG) metal-oxide-semiconductor field-effect transistors (MOSFETs) at 45-nm and below, the metal-gate material consists of a number of grains with different grain orientations. Thus, Monte Carlo (MC) simulation of the threshold voltage ($V_{TH}$) variation caused by the workfunction variation (WFV) using a limited number of samples (i.e., approximately a few hundreds of samples) would be misleading. It is ideal to run the MC simulation using a statistically significant number of samples (>~$10^6$); however, it is expensive in terms of the computing requirement for reasonably estimating the WFV-induced $V_{TH}$ variation in the HK/MG MOSFETs. In this work, a simple matrix model is suggested to implement a computing-inexpensive approach to estimate the WFV-induced $V_{TH}$ variation. The suggested model has been verified by experimental data, and the amount of WFV-induced $V_{TH}$ variation, as well as the $V_{TH}$ lowering is revealed.