• Title/Summary/Keyword: Counter-current

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A Research for China's Corruption Problem and the Government's Counter Measures (중국의 부패상과 정부의 대응에 관한 연구)

  • Chun, Ka-Lim
    • International Area Studies Review
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    • v.12 no.2
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    • pp.351-377
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    • 2008
  • Corruption in China became increasingly serious during the early period of its social transition, resulting in severe economic losses and huge challenges to China's government institution, as well as gradually becoming socially widespread. Recently. China's political corruption is an outcome of the attenuated political control, which has been caused by a systemic change from planned economy to market economy since 1978, and the lack of institutionalization to relieve such transition. Besides, the immature market system and state's intervention in the economy are other factors for the corruption. In short, current China's corruption can be regarded as a structuralized phenomenon. This article identified such circumstance by analyzing the scope, degree, and scale of the corruption. Overall assessment of the some factors suggests that present economic modernization is a principal cause for Chinese corruption while the other factors-monopoly power system in the Chinese Communist Party and the transformation of connection-are important but secondary.

A Study on the Development of Corporate Information Security Level Assessment Models (기업의 정보보호수준 측정모델 개발에 관한 연구)

  • Lee, Hee-Myung;Lim, Jong-In
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.18 no.5
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    • pp.161-170
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    • 2008
  • Despite the recent growth in size and frequency of damages caused by illegal information breaches, current business counter-measures and precautionary systems are greatly limited. Some major companies have developed Information Security Management Systems (ISMS) to safeguard their vital information; however, such measures are largely based on the ISO27001 and lacks in many aspects to grasp the holistic corporate security level and reinforce precautionary measures. The information protection level evaluation model introduced in this paper is a pragmatic evaluative tool that can be utilized to devise effective corporate information security precautionary measures and countermeasures, based on the BSC (Balanced ScoreCard) method for an actual and realistic corporate information security level evaluation possible.

The Modified IPv6 NDP Mechanism for Preventing IP Spoofing (IP 스푸핑 방지를 위한 수정된 IPv6 NDP 메커니즘)

  • Kim Ji-Hong;Nah Jae-Hoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.16 no.2
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    • pp.95-103
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    • 2006
  • IPv6 is a new version of the Internet protocol, designed as the successor to IPv4. Among the changes from IPv4 to IPv6, we focused on the stateless address auto-configuration mechanism. The address auto-configuration mechanism is used by nodes in an IPv6 network to learn the local topology. The current specifications suggest that IPsec AH may be used to secure the mechanism, but there is no security association during address auto-configuration process because it has no initial IP address. As there are so many suity threats, SEND protocol was designed to counter these threats. In this paper we analyzed the security problems in NDP and SEND protocol. So we proposed the Modified NDP mechanism using PKC and AC in order to solve these problems.

A study on the development of SRI(Security Risk Indicator)-based monitoring system to prevent the leakage of personally identifiable information (개인정보 유출 방지를 위한 SRI(Security Risk Indicator) 기반 모니터링 시스템 개발)

  • Park, Sung-Ju;Lim, Jong-In
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.22 no.3
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    • pp.637-644
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    • 2012
  • In our current information focused society, information is regarded as a core asset and the leakage of customers' information has emerged as a critical issue, especially in financial companies. It is very likely that the technology that safeguards which is currently in commercial use is not focused at an enterprise level but is fragmented by function or by only guards portions of a customer's personal information. Therefore, It is necessary to study the systems which monitor the indicators of access at an enterprise level in order to preemptively prevent the compromise of such data. This study takes an enterprise perspective on such systems for a financial company. I will focus on examination of the methods of implementation of the monitoring system, the application of pattern analysis and examination of Security Risk Indicators (SRI). A trial of the monitoring system provided security managers and related departments with proper screening capabilities of information. Therefore, it is possible to establish a systemic counter-plans based on detectable patterns.

Effective study of operating parameters on the membrane distillation processes using various materials for seawater desalination

  • Sandid, Abdelfatah Marni;Neharia, Driss;Nehari, Taieb
    • Membrane and Water Treatment
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    • v.13 no.5
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    • pp.235-243
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    • 2022
  • The paper presents the effect of operating temperatures and flow rates on the distillate flux that can be obtained from a hydrophobic membrane having the characteristics: pore size of 0.15 ㎛; thickness of 130 ㎛; and 85% porosity. That membrane in the present investigation could be the direct contact (DCMD) or the air-gap membrane distillation (AGMD). To model numerically the membrane distillation processes, the two-dimensional computational fluid dynamic (CFD) is used for the DCMD and AGMD cases here. In this work, DCMD and AGMD models have been validated with the experimental data using different flows (Parallel and Counter-current flows) in non-steady-state situations. A good agreement is obtained between the present results and those of the experimental data in the literature. The new approach in the present numerical modeling has allowed examining effects of the nature of materials (Polyvinylidene fluoride (PVDF) polymers, copolymers, and blends) used on thermal properties. Moreover, the effect of the area surface of the membrane (0.021 to 3.15 ㎡) is investigated to explore both the laminar and the turbulent flow regimes. The obtained results found that copolymer P(VDF-TrFE) (80/20) is more effective than the other materials of membrane distillation (MD). The mass flux and thermal efficiency reach 193.5 (g/㎡s), and 83.29 % using turbulent flow and an effective area of 3.1 ㎡, respectively. The increase of feed inlet temperatures and its flow rate, with the reduction of cold temperatures and its flow rate are very effective for increasing distillate water flow in MD applications.

Ensemble-based deep learning for autonomous bridge component and damage segmentation leveraging Nested Reg-UNet

  • Abhishek Subedi;Wen Tang;Tarutal Ghosh Mondal;Rih-Teng Wu;Mohammad R. Jahanshahi
    • Smart Structures and Systems
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    • v.31 no.4
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    • pp.335-349
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    • 2023
  • Bridges constantly undergo deterioration and damage, the most common ones being concrete damage and exposed rebar. Periodic inspection of bridges to identify damages can aid in their quick remediation. Likewise, identifying components can provide context for damage assessment and help gauge a bridge's state of interaction with its surroundings. Current inspection techniques rely on manual site visits, which can be time-consuming and costly. More recently, robotic inspection assisted by autonomous data analytics based on Computer Vision (CV) and Artificial Intelligence (AI) has been viewed as a suitable alternative to manual inspection because of its efficiency and accuracy. To aid research in this avenue, this study performs a comparative assessment of different architectures, loss functions, and ensembling strategies for the autonomous segmentation of bridge components and damages. The experiments lead to several interesting discoveries. Nested Reg-UNet architecture is found to outperform five other state-of-the-art architectures in both damage and component segmentation tasks. The architecture is built by combining a Nested UNet style dense configuration with a pretrained RegNet encoder. In terms of the mean Intersection over Union (mIoU) metric, the Nested Reg-UNet architecture provides an improvement of 2.86% on the damage segmentation task and 1.66% on the component segmentation task compared to the state-of-the-art UNet architecture. Furthermore, it is demonstrated that incorporating the Lovasz-Softmax loss function to counter class imbalance can boost performance by 3.44% in the component segmentation task over the most employed alternative, weighted Cross Entropy (wCE). Finally, weighted softmax ensembling is found to be quite effective when used synchronously with the Nested Reg-UNet architecture by providing mIoU improvement of 0.74% in the component segmentation task and 1.14% in the damage segmentation task over a single-architecture baseline. Overall, the best mIoU of 92.50% for the component segmentation task and 84.19% for the damage segmentation task validate the feasibility of these techniques for autonomous bridge component and damage segmentation using RGB images.

Exploring the Combined Use of LiDAR and Augmented Reality for Enhanced Vertical and Horizontal Measurements of Structural Frames (골조 수직, 수평 측정작업 시 LiDAR 및 AR 기술 적용방안 제시)

  • Park, Inae;Kim, Sangyong
    • Journal of the Korea Institute of Building Construction
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    • v.23 no.3
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    • pp.273-284
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    • 2023
  • This study is centered on the combined use of LiDAR(Light Detection and Ranging) and AR(Augmented Reality) technologies during vertical and horizontal frame measurements in construction projects. The intention is to enhance the quality control procedure, elevate accuracy, and curtail manual labor along with time expenditure. Present methods for accuracy inspection in frame construction often grapple with reliability concerns due to subjective interpretation and the scope for human error. This research recommends the application of LiDAR and AR technologies to counter these issues and augment the efficiency of the inspection process, along with facilitating the dissemination of results. The suggested technique involves the collection of 3D point cloud data of the frame utilizing LiDAR and leveraging this data for checks on construction accuracy. Furthermore, the inspection outcomes are fed into a BIM (Building Information Modeling) model, and the results are visualized via AR. Upon juxtaposing this methodology with the current approach, it is evident that it offers benefits in terms of objective inspection, speed, precise result sharing, and potential enhancements to the overall quality and productivity of construction projects.

Separation of Ag and Zn from Nitrate Leachate of Spent Silver Oxide Batteries by Solvent Extraction with Cyanex272 (Cyanex 272를 이용한 폐산화은배터리 침출액으로부터 Ag 및 Zn의 분리)

  • Sung-Yong Cho;Hyeon Seo;Pan-Pan Sun
    • Resources Recycling
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    • v.33 no.1
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    • pp.31-36
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    • 2024
  • The separation of Ag and Zn from the nitrate leachate of spent silver oxide batteries using Cyanex272 as an extractant was investigated. The extraction of Ag and Zn was affected by the concentrations of nitric acid and the extractant. Cyanex-272 selectively extracted Zn over Ag when the HNO3 concentration was lower than 0.1 mol/L. The co-extracted Ag was removed by stripping with 1 mol/L thiourea. Stripping of Zn from the loaded Cyanex-272 was accomplished using 0.5 mol/L HNO3 after the removal of Ag. The McCabe-Thiele diagrams for the extraction of Zn with Cyanex-272, the scrubbing tripping of Ag with thiourea, and the stripping of Zn with HNO3 were constructed. The results were verified by simulated counter-current extraction and stripping experiments. Finally, a process for the separation of Ag and Zn from silver oxide batteries was proposed.

A Study of Quality Control of Nuclear Medicine Counting System and Gamma Camera (핵의학 계측기기 및 감마카메라의 정도관리 연구)

  • 손혜경;김희중;정해조;정하규;이종두;유형식
    • Progress in Medical Physics
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    • v.12 no.2
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    • pp.103-112
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    • 2001
  • Purpose: The purpose of this study was to investigate the current status of performing nuclear medicine quality control in korea and to test selected protocols of quality control of nuclear medicine counting system and gamma camera. Materials and Methods: Fifty three hospitals were included to investigate the current status of nuclear medicine quality control in korea. The precision of dose calibrator and thyroid uptake system was measured with Tc-99m 35.52 MBq for 2 minuets and Tc-99m 5.14 MBq for 10 sec every one minute, respectively. The sensitivity of CeraSPECT$^{TM}$ with low energy high resolution parallel hole collimator was measured using two cylindrical phantoms with 15 cm in diameter and 12 cm and 30 cm in heights containing Tc-99m. The correction factor for sensitivity of CeraSPECT$^{TM}$ was calculated using phantom data. The system planar sensitivity, uniformity, count rate and spatial resolution were measured for Varicam gamma camera with low energy high resolution parallel hole collimator using 140 keV centered 20% energy window, 256$\times$256 or 512$\times$512 matrix sizes. Results: The quality control of dose calibrator and well counter were showed poor performance status. On the other hand, The quality control of gamma camera and other systems were showed relatively good performance status. The results of precision of dose calibrator and thyroid uptake system was $\pm$1.4%(<$\pm$5%) and chi^2=29.7(>16.92), respectively. It showed that the sensitivity of CeraSPECT$^{TM}$ was higher in center slices compared with the edge slices. After correction of nonuniform sensitivities for patient data, it showed better results compare with prior to correction. System planar sensitivity of Varicam gamma camera was 4.39 CPM/MBq. The observed count rate at 20% loss was 102,407 counts/sec (head 1), 113,427 counts/sec (head 2), when input count rate was 81,926 counts/sec (head 1), 90,741 counts/sec (head 2). The spatial resolution without scatter medium were 8.16 mm of FWHM and 14.85 mm of FWTM. The spatial resolution with scatter medium were 8.87 mm of FWHM and 18.87 mm of FWTM. Conclusion: It is necessary to understand the importance of quality control and to perform quality control of nuclear medicine devices.vices.

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Current Conditions of Habitat for Rana catesbeiana and Trachemys scripta elegans Imported to Jeju-do, Including Proposed Management Plans (제주도에 이입된 황소개구리(Rana catesbeiana)와 붉은귀거북(Trachemys scripta elegans)의 서식실태 및 관리방안)

  • Oh, Hong-Shik;Hong, Chang-Eui
    • Korean Journal of Environment and Ecology
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    • v.21 no.4
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    • pp.311-317
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    • 2007
  • This study was conducted to determine the geographical distribution and habitat for Rana catesbeiana and Trachemys scripta elegans in order to obtain the current basic data on biota needed for establishing a database on non-indigenous species(NIS) in Jeju-do and to develop management plans applicable to Jeju, starting from March 2005 until May 2006. As a result of an inspection, it was found that the habitat for R. catesbeiana in Jeju includes Hankyeong-myeon, Daejeong-eup, and Ahndeok-myeon. These areas are all located on the western side of Jeju-do, and considered to have favorable conditions for R. catesbeiana to inhabit. Thus, it is unlikely that the population of R. catesbeiana will possibly decrease; what's worse, there exists even a risk that it could not only expand to other regions but also do damage to the population of native insecta, fishes, amphibians and reptiles, so this terrible species ought to be exterminated. More than 92 individuals of T. scripta elegans species were found to inhabit in 15 ponds around Jeju Island. T. scripta elegans. as the topmost predator, could destruct the pond ecosystem, and also cause a problem of water pollution due to its excrement. Counter-measures against T. scripta elegans could include publicity activities encouraging self-control of the release of captive T. scripta elegans, extermination plans using its ecological habits, and sign-posting publicizing its hazard to healthy ecosystem at the areas with high population density of T. scripta elegans or at its habitats with high foot traffic, together with the continuous management of NIS(none-indigenous species).