• Journal of the Korea Society of Computer and Information
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• v.23 no.3
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• pp.1-8
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• 2018

In this paper, we propose a new page replacement policy using recency and frequency on hybrid main memory. The proposal has two features. First, when a page fault occurs in the main memory, the proposal allocates it to DRAM, regardless of operation types such as read or write. The page allocated by the page fault is likely to be high probability of re-reference in the near future. Our allocation can reduce the frequency of write operations in PCM. Second, if the write operations are frequently performed on pages of PCM, the pages are migrated from PCM to DRAM. Otherwise, the pages are maintained in PCM, to reduce the number of unnecessary page migrations from PCM. In our experiments, the proposal reduced the number of page migrations from PCM about 32.12% on average and reduced the number of write operations in PCM about 44.64% on average, compared to CLOCK-DWF. Moreover, the proposal reduced the energy consumption about 15.61%, and 3.04%, compared to other page replacement policies.

• Transactions of the Society of Information Storage Systems
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• v.1 no.1
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• pp.34-41
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• 2005

We report some recent results in the rewritable Blu-ray Disc with enhanced overwrite cyclability by using the growth dominant eutectic based Ge(Sb70Te30)+Sb recording layer, GeN interface layer and write strategy optimization. We have developed phase-change optical media with appropriate write strategy for 36(i.e., 1X)-72Mbps(i.e., 2X) dual speed Blu-ray Disc system and fur the future high speed optical data storage. For recording layer, eutectic-based Ge(Sb70Te30)+Sb material was used and Sb/Te ratio and Ge content were optimized to obtain proper erasability and archival stability of recorded amorphous marks. The recording layer is wrapped up in GeN interface layers to obtain overwrite cyclability and higher crystallization speed. In addition, we designed appropriate write strategy so called Time-Shifted Multipulse (TSMP) write strategy where starting position of multipulse parts are shined from reference clock. With this write strategy, the jitter characteristics of the disc was improved and we found that leading edge jitter was improved much more than trailing edge jitter in 1X-2X speed recording. Finally, we investigated the higher speed feasibility of 144Mbps(i.e., 4X) by adopting some elemental doping to the eutectic based Ag-In-Sb-Te recording layer and structural optimization of constitution layers in Blu-ray Disc. In the paper, we report the effect of Sn addition for the feasibility of higher speed recording. The addition of Sn shows increases of the crystallization speed of phase change recording layer.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.6
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• pp.57-62
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• 2022

Recently, fast storage media such as phage-change memory (PCM) emerge, and memory management policies for slow disk storage need to be revisited. In this paper, we propose a new page replacement policy that makes use of PCM as a swap device of virtual memory systems. The proposed policy aims at reducing write traffic to the swap device as well as reducing the number of page faults pursued by traditional page replacement policies. This is because a write operation in PCM is slow and PCM has limited write endurances. Specifically, the proposed policy focuses on the reduction of page faults when the memory load of the system is high, but it aims at reducing write traffic to storage when free memory space is sufficient. Simulation experiments with various memory reference traces show that the proposed policy reduces write traffic to PCM without performance degradations.

• Journal of Korean Library and Information Science Society
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• v.44 no.1
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• pp.409-432
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• 2013

The purpose of this study is to examine 5 writing guidelines of reference collection development policy(RCDP) and to identify major elements of RCDP through the comparison and analysis of 24 RCDP in academic libraries in the U.S. As a result of this study, a total of 9 elements(5 core elements and 4 selective elements) were identified. Five core elements were (1) introduction, (2) scope, size, and level, (3) format, (4) types, and (5) management(i.e., selection, weeding, evaluation, and responsibilities) of reference collection. The results of this study would be helpful to those academic libraries which are planning to write RCDP in academic libraries in the near future.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.86-91
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• 2022

Cache bypassing is a scheme to prevent unnecessary cache blocks from occupying the capacity of the cache for avoiding cache contamination. This method is introduced to alleviate the problems of non-volatile memories (NVMs)-based memory system. However, the prior works have been studied without considering wear-out attack. Malicious writing to a small area in NVMs leads to the failure of the system due to the limited write endurance of NVMs. This paper proposes a novel scheme to prolong the lifetime with higher resistance for the wear-out attack. First, the memory reference pattern is found by modified reuse distance calculation for each cache block. If a cache block is determined as the target of the attack, it is forwarded to higher level cache or main memory without updating the NVM-based cache. The experimental results show that the write endurance is improved by 14% on average and 36% on maximum.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.1
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• pp.31-36
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• 2024

Recently, mobile apps that utilize AI technologies are increasing. In the personal mobile environment, performance degradation may occur during the training phase of large AI workload due to limitations in memory capacity. In this paper, we extract memory reference traces of AI workloads and analyze their characteristics. From this analysis, we observe that AI workloads can cause frequent storage access due to weak temporal locality and irregular popularity bias during memory write operations, which can degrade the performance of mobile devices. Based on this observation, we discuss ways to efficiently manage memory write operations of AI workloads using persistent memory-based swap devices. Through simulation experiments, we show that the system architecture proposed in this paper can improve the I/O time of mobile systems by more than 80%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.542-547
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• 1996

So far, this report is written by knowledge auf standard through several reference drawing and experienced contents with drawing ere die of Item. The contents about actual production is so huge that I will write about it next time. Comparatively high added value Hemming die of is important for automobile development but its not proper for producing small quantity. In the future, I believe that simple easy to correct and reasonable price hemming die will be producted

• Journal of Acupuncture Research
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• v.27 no.4
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• pp.147-178
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• 2010

Objectives : This study was to propose the improved instruction for authors and research ethic regulations by the comparative analysis of those of the domestic journals, for the purpose of enhancing the citation rate of Journal of Korean Acupuncture and Moxibustion Society. Methods : Narrative review method was used for comparatively analyzing instruction for authors of 34 domestic journals, especially focused on how to write a reference. Thereafter, in order to elucidate the drawbacks of current instruction for authors and research ethic regulations of the acupuncture and moxibustion society, the well prepared instructions and research ethic regulations was selected from them, which were compared with the present instructions for authors and research ethic regulations of the acupuncture and moxibustion society. Results : As a result of the comparative analysis of instruction for authors in the 34 domestic journals, style for references was based largely on that of National Library of Medicine and vancouver at the same time. The number of reference was limited according to types of writings. for example, the original article and case report was frequently limited to 40 and 20 references respectively. Authors were mostly listed up to six. If there are more, the first three or six authors were listed with 'et al'. it was generally recommended that using abstracts as references should be avoided and References to papers accepted but not yet published should be designated as 'in press' or 'forthcoming', and that the names of journals should be set in italics and abbreviated according to the List of Journals Indexed for Medline (formerly Index Medicus) published by the National Library of Medicine or koreanmed or WHO-IST, etc. In addition, citation of electrical literature, English writing of reference and obligational citation of more than two articles in the journals were encouraged. In consequence of comparison between well prepared instructions and research ethic regulations of the selected journals and those of current instructions for authors and research ethic regulations of the acupuncture and moxibustion society, the followings were needed to be added or revised. 1. Requirements for case reports were not mentioned. 2. Reporting Guidelines for Specific Study Designs were not included. 3. Previous Orthography of herbal prescription should be revised. 4. Orthography of authors and guidelines for writing article constituents such as title, abstract, introduction, method, statistics, results, discussions were not presented. 5. How to write a reference was so simplified. 6. Definition of Research Ethical Misconduct was omitted and establishment, management and members of committee for research ehtics were not mentioned, 7. Information, reception and investigative procedures of Research Ethical Misconduct was not specified. Conclusions : For the development of Journal of Korean Acupuncture and Moxibustion Society, apporopriate revision of the instruction for author and research ethic regulations should be made based upon the above findings. English writing of reference were believed to be one of the alternatives enhancing citation rate.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.2
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• pp.223-231
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• 2015

As smartphones support a variety of applications and their memory demand keeps increasing, the design of an efficient memory management policy is becoming increasingly important. Meanwhile, as nonvolatile memory (NVM) technologies such as PCM and STT-MRAM have emerged as new memory media of smartphones, characterizing memory references for NVM-based smartphone memory systems is needed. For the deep understanding of memory access features in smartphones, this paper performs comprehensive analysis of memory references for various smartphone applications. We first analyze the temporal locality and frequency of memory reference behaviors to quantify the effects of the two properties with respect to the re-reference likelihood of pages. We also analyze the skewed popularity of memory references and model it as a Zipf-like distribution. We expect that the result of this study will be a good guidance to design an efficient memory management policy for future smartphones.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.4
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• pp.251-257
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• 2004

Nonvolatile FRAMs with a design rule of 0.18 ${\mu}m$ were developed for the high performance smart card. A 1Mb FRAM was embedded in place of an EEPROM and a 64Kb FRAM was embedded in place of a. SRAM. It was confirmed that the FRAMs performed the roles of the EEPROM and SRAM successfully using the asynchronous write/read operation method and the one time programming (OTP) scheme. The cycle time of the FRAM was 10 MHz, which remarkably improved the write performance of the smart card in comparison with that of the conventional smart card with an EEPROM. Additionally, a simple and smart bit-line reference scheme for the future FRAM device having a 1T1C cell type was proposed.