• Title/Summary/Keyword: memory protection

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The adverse impact of personal protective equipment on firefighters' cognitive functioning

  • Park, Juyeon
    • The Research Journal of the Costume Culture
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    • v.27 no.1
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    • pp.1-10
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    • 2019
  • Firefighters wear Personal Protective Equipment (PPE) for protection from environmental hazards. However, due to the layers of protective functions, the PPE inevitably adds excessive weight, bulkiness, and thermal stress to firefighters. This study investigated the adverse impact of wearing PPE as an occupational stressor on the firefighter's cognitive functioning. Twenty-three firefighters who had been involved in firefighting at least for 1 year were recruited. The overall changing trend in the firefighter's cognitive functioning (short-term memory, long-term memory, and inductive reasoning) was measured by the scores of three standardized cognitive tests at the baseline and the follow-up, after participating in a moderate-intensity physical activity, wearing a full ensemble of the PPE. The study findings evinced the negative impact of the PPE on the firefighter's cognitive functioning, especially in short-term memory and inductive reasoning. No significant influence was found on the firefighter's long-term memory. The results were consistent when the participant's age and BMI were controlled. The outcomes of the present study will not only fill the gap in the literature, but also provide critical justification to stakeholders, including governments, policymakers, academic communities, and industry, for such efforts to improve human factors of the firefighter's PPE by realizing the negative consequences of the added layers and protective functions on their occupational safety. Study limitations and future directions were also discussed.

Dynamic analysis of a historical monument: retrofit using shape memory alloy wires

  • Hamdaoui, Karim;Benadla, Zahira
    • Smart Structures and Systems
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    • v.13 no.3
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    • pp.375-388
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    • 2014
  • The effectiveness of using the advanced seismic protection technology based on shape memory alloy (SMA) dampers to preserve a historical minaret is investigated. The proposed studied case, the minaret of Mansourah, is a seven century old minaret located in Tlemcen, Algeria. Its original height was of 47m, while nowadays, the monument is half destructed and its current height reaches the 40m. The proposed seismic retrofit is based on the technique that utilizes SMA wires as dampers for the upper flexible part of the minaret. The effectiveness of the proposed technique is numerically evaluated via non-linear finite element analysis using the structural software ANSYS. The effectiveness of the proposed device in mitigating the seismic hazard is demonstrated by the effective reduction in its dynamic response.

Framework-assisted Selective Page Protection for Improving Interactivity of Linux Based Mobile Devices (리눅스 기반 모바일 기기에서 사용자 응답성 향상을 위한 프레임워크 지원 선별적 페이지 보호 기법)

  • Kim, Seungjune;Kim, Jungho;Hong, Seongsoo
    • Journal of KIISE
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    • v.42 no.12
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    • pp.1486-1494
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    • 2015
  • While Linux-based mobile devices such as smartphones are increasingly used, they often exhibit poor response time. One of the factors that influence the user-perceived interactivity is the high page fault rate of interactive tasks. Pages owned by interactive tasks can be removed from the main memory due to the memory contention between interactive and background tasks. Since this increases the page fault rate of the interactive tasks, their executions tend to suffer from increased delays. This paper proposes a framework-assisted selective page protection mechanism for improving interactivity of Linux-based mobile devices. The framework-assisted selective page protection enables the run-time system to identify interactive tasks at the framework level and to deliver their IDs to the kernel. As a result, the kernel can maintain the pages owned by the identified interactive tasks and avoid the occurrences of page faults. The experimental results demonstrate the selective page protection technique reduces response time up to 11% by reducing the page fault rate by 37%.

Study on Memory Data Encryption of Windows Hibernation File (윈도우 최대 절전 모드 파일의 메모리 데이터 암호화 기법 연구)

  • Lee, Kyoungho;Lee, Wooho;Noh, Bongnam
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.5
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    • pp.1013-1022
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    • 2017
  • Windows hibernation is a function that stores data of physical memory on a non-volatile media and then restores the memory data from the non-volatile media to the physical memory when the system is powered on. Since the hibernation file has memory data in a static state, when the attacker collects it, key information in the system's physical memory may be leaked. Because Windows does not support protection for hibernation files only, we need to protect the memory that is written to the hibernate file. In this paper, we propose a method to encrypt the physical memory data in the hibernation file to protect the memory data of the processes recorded in the hibernation file. Hibernating procedure is analyzed to encrypt the memory data at the hibernating and the encryption process for hibernation memory is implemented to operate transparently for each process. Experimental results show that the hibernation process memory encryption tool showed about 2.7 times overhead due to the crypt cost. This overhead is necessary to prevent the attacker from exposing the plaintext memory data of the process.

The Improvement of Learning and Memory Ability of Normal Persons by BF-7

  • Lee, Sang-Hyung;Kim, Yong-Sik;Kang, Yong-Koo;Kwon, Oh-Sang;Shin, Yong-Kyoo;Song, Jln-Ho;Lee, Moo-Yeol;Lee, Kwang-Gill;Yeo, Joo-Hong;Lee, Won-Bok;Lee, Tae-Jin;Kim, Sung-Su
    • The Korean Journal of Physiology and Pharmacology
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    • v.8 no.6
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    • pp.307-312
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    • 2004
  • To investigate whether BF-7, extracted from Bombyx mori, improved learning and memory of ordinary people, Rey-Kim Memory Test was performed with placebo group (32 persons), 200 mg BF-7 treated group (33 persons) and 400 mg BF-7 treated group (34 persons). BF-7 enhanced significantly learning and memory function in a dose-dependent manner. To know how BF-T plays such a positive role, we measured the concentration of acetylcholine in the brain from memory impairment animal model. Treatment of BF-7 significantly increased the concentration of acetylcholine. So, it is supposed that the protection of cholinergic neuron and/or keeping proper concentration of acetylcholine might be one of the mechanisms by which BF-7 improve brain function. So, our results suggest that the BF-7 is effective material for improving learning and memory ability.

Design of Graphic Memory for QVGA-Scale LCD Driver IC (QVGA급 LCD Driver IC의 그래픽 메모리 설계)

  • Kim, Hak-Yun;Cha, Sang-Rok;Lee, Bo-Sun;Jeong, Yong-Cheol;Choi, Ho-Yong
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.47 no.12
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    • pp.31-38
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    • 2010
  • This paper presents the design of a graphic memory for QVGA-scale LCD Driver IC (LDI). The graphic memory is designed based on the pseudo-SHAM for the purpose of small area, and the memory cell structure is designed using a bit line partitioning method to improve sensing characteristics and drivabilties in the line-read operation. Also, a collision protection circuit using C-gate is designed to control collisions between read/write operations and self-refresh/line-read operations effectively. The graphic memory circuit has been designed in transistor level using $0.18{\mu}m$ CMOS technology library and the operations of the graphic memory have been verified using Hspice. The results show that the bit-bitb line voltage difference, ${\Delta}V$ increases by 40%, the charge sharing time between bit and bitb voltages $T_{CHGSH}$ decreases by 30%, and the current during line-read decreases by 40%.

Host Responses from Innate to Adaptive Immunity after Vaccination: Molecular and Cellular Events

  • Kang, Sang-Moo;Compans, Richard W.
    • Molecules and Cells
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    • v.27 no.1
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    • pp.5-14
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    • 2009
  • The availability of effective vaccines has had the most profound positive effect on improving the quality of public health by preventing infectious diseases. Despite many successful vaccines, there are still old and new emerging pathogens against which there is no vaccine available. A better understanding of how vaccines work for providing protection will help to improve current vaccines as well as to develop effective vaccines against pathogens for which we do not have a proper means to control. Recent studies have focused on innate immunity as the first line of host defense and its role in inducing adaptive immunity; such studies have been an intense area of research, which will reveal the immunological mechanisms how vaccines work for protection. Toll-like receptors (TLRs), a family of receptors for pathogen-associated molecular patterns on cells of the innate immune system, play a critical role in detecting and responding to microbial infections. Importantly, the innate immune system modulates the quantity and quality of long-term T and B cell memory and protective immune responses to pathogens. Limited studies suggest that vaccines which mimic natural infection and/or the structure of pathogens seem to be effective in inducing long-term protective immunity. A better understanding of the similarities and differences of the molecular and cellular events in host responses to vaccination and pathogen infection would enable the rationale for design of novel preventive measures against many challenging pathogens.

Edge-Preserving Algorithm for Block Artifact Reduction and Its Pipelined Architecture

  • Vinh, Truong Quang;Kim, Young-Chul
    • ETRI Journal
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    • v.32 no.3
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    • pp.380-389
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    • 2010
  • This paper presents a new edge-protection algorithm and its very large scale integration (VLSI) architecture for block artifact reduction. Unlike previous approaches using block classification, our algorithm utilizes pixel classification to categorize each pixel into one of two classes, namely smooth region and edge region, which are described by the edge-protection maps. Based on these maps, a two-step adaptive filter which includes offset filtering and edge-preserving filtering is used to remove block artifacts. A pipelined VLSI architecture of the proposed deblocking algorithm for HD video processing is also presented in this paper. A memory-reduced architecture for a block buffer is used to optimize memory usage. The architecture of the proposed deblocking filter is verified on FPGA Cyclone II and implemented using the ANAM 0.25 ${\mu}m$ CMOS cell library. Our experimental results show that our proposed algorithm effectively reduces block artifacts while preserving the details. The PSNR performance of our algorithm using pixel classification is better than that of previous algorithms using block classification.

CCR7 Ligands Induced Expansion of Memory CD4+ T Cells and Protection from Viral Infection (CCR7 Ligand의 Memory CD4+ T 세포 증가유도 및 바이러스 감염에 대한 방어효과)

  • Eo, Seong-Kug;Cho, Jeong-Gon
    • IMMUNE NETWORK
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    • v.3 no.1
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    • pp.29-37
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    • 2003
  • Background: CC chemokine receptor (CCR) 7 and cognate CCR7 ligands, CCL21 (formerly secondary lymphoid tissue chemokine [SLC]) and CCL19 (formerly Epstein-Barr virus-induced molecule 1 ligand chemokine [ELC]), were known to establish microenvironment for the initiation of immune responses in secondary lymphoid tissue. As described previously, coadministration of DNA vaccine with CCR7 ligand-encoding plasmid DNA elicited enhanced humoral and cellular immunity via increasing the number of dendritic cells (DC) in secondary lymphoid tissue. The author hypothesized here that CCR7 ligand DNA could effectively expand memory CD4+ T cells to protect from viral infection likely via increasing DC number. Methods: To evaluate the effect of CCR7 ligand DNA on the expansion of memory CD4+ T cells, DO11.10.BALB/c transgenic (Tg)-mice, which have highly frequent ovalbumin $(OVA)_{323-339}$ peptide-specific CD4+ T cells, were used. Tg-mice were previously injected with CCR7 ligand DNA, then immunized with $OVA_{323-339}$ peptide plus complete Freund's adjuvant. Subsequently, memory CD4+ T cells in peripheral blood lymphocytes (PBL) were analyzed by FACS analysis for memory phenotype ($CD44^{high}$ and CD62 $L^{low}$) at memory stage. Memory CD4+ T cells recruited into inflammatory site induced with OVA-expressing virus were also analyzed. Finally, the protective efficacy against viral infection was evaluated. Results: CCR7 ligand DNA-treated Tg-mice showed more expanded $CD44^{high}$ memory CD4+ T cells in PBL than control vector-treated animals. The increased number of memory CD4+ T cells recruited into inflammatory site was also observed in CCR7 ligand DNA-treated Tg-mice. Such effectively expanded memory CD4+ T cell population increased the protective immunity against virulent viral infection. Conclusion: These results document that CCR7 and its cognate ligands play an important role in intracellular infection through establishing optimal memory T cell. Moreover, CCR7 ligand could be useful as modulator in DNA vaccination against viral infection as well as cancer.

Shape memory alloy (SMA)-based Superelasticity-assisted Slider (SSS): an engineering solution for practical aseismic isolation with advanced materials

  • Narjabadifam, Peyman;Noori, Mohammad;Cardone, Donatello;Eradat, Rasa;Kiani, Mehrdad
    • Smart Structures and Systems
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    • v.26 no.1
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    • pp.89-102
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    • 2020
  • Shape memory alloy (SMA)-based Superelasticity-assisted Slider (SSS) is proposed as an engineering solution to practically exploit the well-accepted advantages of both sliding isolation and SMA-based recentering. Self-centering capability in SSS is provided by austenitic SMA cables (or wire ropes), recently attracting a lot of interest and attention in earthquake engineering and seismic isolation. The cables are arranged in various novel and conventional configurations to make SSS versatile for aseismic design and retrofit of structures. All the configurations are detailed with thorough technical drawings. It is shown that SSS is applicable without the need for Isolation Units (IUs). IUs, at the same time, are devised for industrialized applications. The proof-of-concept study is carried out through the examination of mechanical behavior in all the alternative configurations. Force-displacement relations are determined. Isolation capabilities are predicted based on the decreases in seismic demands, estimated by the increases in effective periods and equivalent damping ratios. Restoring forces normalized relative to resisting forces are assessed as the criteria for self-centering capabilities. Lengths of SMA cables required in each configuration are calculated to assess the cost and practicality. Practical implementation is realized by setting up a small-scale IU. The effectiveness of SSS under seismic actions is evaluated using an innovative computer model and compared to those of well-known Isolation Systems (ISs) protecting a reference building. Comparisons show that SSS seems to be an effective IS and suitable for earthquake protection of both structural and non-structural elements. Further research aimed at additional validation of the system are outlined.