• 제목/요약/키워드: Memory Safety

검색결과 227건 처리시간 0.028초

Scratchpad Memory Architectures and Allocation Algorithms for Hard Real-Time Multicore Processors

  • Liu, Yu;Zhang, Wei
    • Journal of Computing Science and Engineering
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    • 제9권2호
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    • pp.51-72
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    • 2015
  • Time predictability is crucial in hard real-time and safety-critical systems. Cache memories, while useful for improving the average-case memory performance, are not time predictable, especially when they are shared in multicore processors. To achieve time predictability while minimizing the impact on performance, this paper explores several time-predictable scratch-pad memory (SPM) based architectures for multicore processors. To support these architectures, we propose the dynamic memory objects allocation based partition, the static allocation based partition, and the static allocation based priority L2 SPM strategy to retain the characteristic of time predictability while attempting to maximize the performance and energy efficiency. The SPM based multicore architectural design and the related allocation methods thus form a comprehensive solution to hard real-time multicore based computing. Our experimental results indicate the strengths and weaknesses of each proposed architecture and the allocation method, which offers interesting on-chip memory design options to enable multicore platforms for hard real-time systems.

폐경기 기억력에 대한 한약의 효과 : 체계적 문헌고찰 (The Efficacy of Oriental Medicine on Memory in Menopause: A Systemic Review)

  • 이수형;권하린;조인정;천세은;김송백
    • 대한한방부인과학회지
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    • 제36권2호
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    • pp.20-35
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    • 2023
  • Objectives: The purpose of this study is to review clinical studies and investigate the efficacy and safety of oriental medicine on memory in menopausal women. Methods: 'menopause', 'memory', 'oriental medicine' were searched on 4 online databases (Cochrane Library, Pubmed, CNKI, OASIS). Randomized controlled trials (RCTs) that evaluated menopausal memory with oriental medicine treatment were included. The methodological quality of each RCT was assessed by using Cochrane risk of bias tool. Results: 8 RCTs were selected among 1067 articles. The overall risk of bias was evaluated as uncertain. 5 studies showed that oriental medicine alone was significant effective, but 1 long-term study with the same oriental medicine did not sustain the effect, and 2 studied were not statistically significant. Conclusions: Oriental medicine can be an effective option for improving memory in menopausal women. but considering the small number and quality of studies, inconsistent and insufficient evidence, further well-designed studies are needed to confirm the efficacy and safety of this treatment.

메모리가 제한적인 자바가상기계에서의 지역 재사용 (Reusing Local Regions in Memory-limited Java Virtual Machines)

  • 김태인;김성건;한환수
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제34권6호
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    • pp.562-571
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    • 2007
  • 많은 연구들을 통해 수행 속력, 효율성, 용이성, 안전성을 위하여 메모리 관리 기법들을 개선시켰다. 그러한 방법들 중에서 지역별 메모리 관리 기법은 각각의 객체 할당 위치에서 따라 정해진 지역에 할당 시키고 그 지역이 제거된다면 그 곳에 할당된 모든 객체의 메모리를 반환하는 방법이다. 본 논문에서는 메모리 제약적인 환경에서 힙 메모리 사용량을 줄이기 위해 로컬 지역을 재사용하는 방법을 제시한다. 기본 아이디어는 현재 함수가 수행될 동안 사용하지 않는 상위 로컬 지역을 재사용하는 것이다. 이러한 방법을 사용함으로써 메모리 제약적인 환경에서 메모리의 한계를 극복할 수 있을 것이다.

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

  • 어성국;조정곤
    • IMMUNE NETWORK
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    • 제3권1호
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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.

Naive Bayes-LSTM 기반 예지정비 플랫폼 적용을 통한 화물 상차 시스템의 운영 안전성 및 신뢰성 확보 연구 (On the Parcel Loading System of Naive Bayes-LSTM Model Based Predictive Maintenance Platform for Operational Safety and Reliability)

  • 황선우;김진오;최준우;김영민
    • 대한안전경영과학회지
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    • 제25권4호
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    • pp.141-151
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    • 2023
  • Recently, due to the expansion of the logistics industry, demand for logistics automation equipment is increasing. The modern logistics industry is a high-tech industry that combines various technologies. In general, as various technologies are grafted, the complexity of the system increases, and the occurrence rate of defects and failures also increases. As such, it is time for a predictive maintenance model specialized for logistics automation equipment. In this paper, in order to secure the operational safety and reliability of the parcel loading system, a predictive maintenance platform was implemented based on the Naive Bayes-LSTM(Long Short Term Memory) model. The predictive maintenance platform presented in this paper works by collecting data and receiving data based on a RabbitMQ, loading data in an InMemory method using a Redis, and managing snapshot DB in real time. Also, in this paper, as a verification of the Naive Bayes-LSTM predictive maintenance platform, the function of measuring the time for data collection/storage/processing and determining outliers/normal values was confirmed. The predictive maintenance platform can contribute to securing reliability and safety by identifying potential failures and defects that may occur in the operation of the parcel loading system in the future.

Evaluation of effectiveness of fault-tolerant techniques in a digital instrumentation and control system with a fault injection experiment

  • Kim, Man Cheol;Seo, Jeongil;Jung, Wondea;Choi, Jong Gyun;Kang, Hyun Gook;Lee, Seung Jun
    • Nuclear Engineering and Technology
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    • 제51권3호
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    • pp.692-701
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    • 2019
  • Recently, instrumentation and control (I&C) systems in nuclear power plants have undergone digitalization. Owing to the unique characteristics of digital I&C systems, the reliability analysis of digital systems has become an important element of probabilistic safety assessment (PSA). In a reliability analysis of digital systems, fault-tolerant techniques and their effectiveness must be considered. A fault injection experiment was performed on a safety-critical digital I&C system developed for nuclear power plants to evaluate the effectiveness of fault-tolerant techniques implemented in the target system. A software-implemented fault injection in which faults were injected into the memory area was used based on the assumption that all faults in the target system will be reflected in the faults in the memory. To reduce the number of required fault injection experiments, the memory assigned to the target software was analyzed. In addition, to observe the effect of the fault detection coverage of fault-tolerant techniques, a PSA model was developed. The analysis of the experimental result also can be used to identify weak points of fault-tolerant techniques for capability improvement of fault-tolerant techniques

관광체험요소가 관광지의 기억, 만족 충성도에 미치는 영향에 관한 연구 (A Study on the Influence of Tourism Experience Factors on the Memory, Satisfaction and Loyalty of Tourist Attractions)

  • 박완규;김용범;최유진
    • 대한안전경영과학회지
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    • 제19권2호
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    • pp.147-157
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    • 2017
  • The tourism experience factor is an essential source of competitive advantage in the tourism industry and is an important factor for predicting future tourism behavior. Tourism experience elements can be composed of areas of education, entertainment, aesthetics and deviance (Pine and Gilmore, 1998). This study examines the effect of tourist experience factors on tourist loyalty and it is meaningful to see if the experiential economic theory of Pine and Gilmore (1999) is applicable. In order to achieve the purpose of this study, we conducted a questionnaire survey on tourists using experiential tourism factors. As a result, it was found that recreational experiential factors had a significant effect on memory. Memory has a significant effect on both visitor satisfaction and tourist loyalty. This study has academic significance because it focuses on the tourism experience factor which is the core of experiential economic theory. Practical significance is that a lot of experiential contents should be found in order to better match the tourist experience factor to the requirements of visitors to the tourist site. As a result, it is expected to generate revenue and improve its competitiveness.

A method for preventing online games hacking using memory monitoring

  • Lee, Chang Seon;Kim, Huy Kang;Won, Hey Rin;Kim, Kyounggon
    • ETRI Journal
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    • 제43권1호
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    • pp.141-151
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    • 2021
  • Several methods exist for detecting hacking programs operating within online games. However, a significant amount of computational power is required to detect the illegal access of a hacking program in game clients. In this study, we propose a novel detection method that analyzes the protected memory area and the hacking program's process in real time. Our proposed method is composed of a three-step process: the collection of information from each PC, separation of the collected information according to OS and version, and analysis of the separated memory information. As a result, we successfully detect malicious injected dynamic link libraries in the normal memory space.

멀티코어 시스템에서 TLB Lockdown에 의한 TLB Miss 영향 분석 (Investigation on TLB Miss Impact through TLB Lockdown in Multi-core Systems)

  • 송대영;박시형;김형신
    • 대한임베디드공학회논문지
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    • 제17권1호
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    • pp.59-65
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    • 2022
  • Virtual memory is used as the method to ensure the safety of the system through memory protection in the real-time system. TLB miss caused by using virtual memory makes the real-time system WCET more pessimistically. TLB lockdown can be applied as a method to improve this problem. However, processors with limited TLB lockdown entries, a selection criterion is needed to efficiently utilize the TLB lockdown entry. In this paper, the most frequently accessed virtual pages in the process are applied to the TLB lockdown by analyzing memory profiling. The results showed that micro data TLB miss stall cycle and main data TLB miss stall cycle of the processor decreased by at least 4.7% and up to 29.7%.

AUTOSAR 플랫폼 기반 CDD를 활용한 비휘발성 메모리 수명 연장 기법 (A Non-volatile Memory Lifetime Extension Scheme Based on the AUTOSAR Platform using Complex Device Driver)

  • 신주석;손정호;이은령;오세진;안광선
    • 대한임베디드공학회논문지
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    • 제8권5호
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    • pp.235-242
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    • 2013
  • Recently, the number of automotive electrical and electronic system has been increased because the requirements for the convenience and safety of the drivers and passengers are raised. In most cases, the data for controlling the various sensors and automotive electrical and electronic system used in runtime should be stored on the internal or external non-volatile memory of the ECU(Electronic Control Units). However, the non-volatile memory has a constraint with write limitation due to the hardware characteristics. The limitation causes fatal accidents or unexpected results if the non-volatile memory is not managed. In this paper, we propose a management scheme for using non-volatile memory to prolong the writing times based on AUTOSAR(AUTOmotive Open System Architecture) platform. Our proposal is implemented on the CDD(Complex Device Driver) and uses an algorithm which swaps a frequently modified block for a least modified block. Through the development of the prototype, the proposed scheme extends the lifetime of non-volatile memory about 1.08 to 2.48 times than simply using the AUTOSAR standard.