• Title/Summary/Keyword: Data Memory

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A Recommendation System of Exponentially Weighted Collaborative Filtering for Products in Electronic Commerce (지수적 가중치를 적용한 협력적 상품추천시스템)

  • Lee, Gyeong-Hui;Han, Jeong-Hye;Im, Chun-Seong
    • The KIPS Transactions:PartB
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    • v.8B no.6
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    • pp.625-632
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    • 2001
  • The electronic stores have realized that they need to understand their customers and to quickly response their wants and needs. To be successful in increasingly competitive Internet marketplace, recommender systems are adapting data mining techniques. One of most successful recommender technologies is collaborative filtering (CF) algorithm which recommends products to a target customer based on the information of other customers and employ statistical techniques to find a set of customers known as neighbors. However, the application of the systems, however, is not very suitable for seasonal products which are sensitive to time or season such as refrigerator or seasonal clothes. In this paper, we propose a new adjusted item-based recommendation generation algorithms called the exponentially weighted collaborative filtering recommendation (EWCFR) one that computes item-item similarities regarding seasonal products. Finally, we suggest the recommendation system with relatively high quality computing time on main memory database (MMDB) in XML since the collaborative filtering systems are needed that can quickly produce high quality recommendations with very large-scale problems.

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Hybrid Priority Medium Access Control Scheme for Wireless Body Area Networks (무선 인체통신 네트워크를 위한 복합 우선순위 MAC 기법)

  • Lee, In-Hwan;Lee, Gun-Woo;Cho, Sung-Ho;Choo, Sung-Rae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.9B
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    • pp.1305-1313
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    • 2010
  • Last few years, wireless personal area network (WPAN) has been widely researched for various healthcare applications. Due to restriction of device hardware (e.g., energy and memory), we need to design a highly-versatile MAC layer protocol for WBAN (Wireless Body Area Network). In addition, when an emergency occurs to a patient, a priority mechanism is necessitated for a urgent message to get through to the final destination. This paper presents a priority mechanism referred to as hybrid priority MAC for WBAN. Through extensive simulation, we show the proposed MAC protocol can minimize the average packet latency for urgent data. Thus, when patients have an emergency situation, our MAC allows adequate assistance time and medical treatment for patients. The simulation based on NS-2 shows that our Hybrid Priority MAC has the good performance and usability.

Study on pathology of Alzheimer's disease, trends and future strategy for research (치매의 병리(病理), 연구동향(硏究動向)과 향후(向後) 연구전략(硏究戰略)에 대(對)한 고찰(考察))

  • Oh, Young-Sun;Kim, Sung-Hoon
    • Journal of Haehwa Medicine
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    • v.8 no.1
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    • pp.793-825
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    • 1999
  • For the development of drugs for alzheimer,s disease, the study was done to review the oriental pathology, clinical data, recent trends for research and strategy for future study. The results were as follows: 1. The medical term Chi-dsi implying alzheimer,s disease was referred for the first time in a medical book, Hwatasheneubijeon written by Hwa-Ta and its differentiation and treatment were studied more in Ming or Ching dynasties. Chi-dai can be differentated as weak(虛) syndrome and Shi(實) syndrome. This can be caused by deficiencies of renal Yin, renal Yang, cardiac Yin and hepatic blood, while that by deficiencies of pathological fluid(痰飮) and clotted blood(瘀血). 2. Dementia can be roughly classified as alzheimer's disease and multi-infarct disease. Its causes were known to be cholinergic transmitter, C-peptide, amyloid-${\beta}$, apolipoprotein, APP(amyloid precursor protein), TGF, MMP-9 and free radical. 3. In Korea experimental studies were chiefly done for the elimataion of C-peptide, amyloid-${\beta}$, apolipoprotein, APP for alzheimer's disease, for the development of drug inhibiting degerative change following CVA and loss of memory and also administrative measure was done by support of government. 4. Drugs of dimentia developed so far were Chi-Dai dan, extracts from aloe, mushroom, green tea, Ganoderma and also folic acid, vitamin C, DHEA and silk amino acid were reported to be effective in dimenta. 5. Future strategic research had better be done on dementia-inducing factors such as acetylcholine, C-peptide, amyloid-${\beta}$, apolipoprotein, APP, TGF, MMP-9 and free radical, development of animal model for dimentia, clinical study, epidemiology, nursing and administrative studies and also consortium for dimentia research should be formed so that repeated investment be avoided.

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Post-Intensive Care Syndrome Experience among Critical Care Survivors: A Meta-synthesis of Qualitative Research (집중치료 후 증후군 경험에 관한 질적 통합 연구)

  • Kang, Jiyeon;Jeong, Yeon Jin;Yun, Sun Young;Lee, Min Ju;Baek, Min Jung;Shin, So Yeung;Hong, Hee Jin;Kim, Soo Kyung;Cho, Young Shin
    • Journal of Korean Critical Care Nursing
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    • v.10 no.1
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    • pp.13-30
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    • 2017
  • Purpose: The purpose of this study was to integrate the results of qualitative studies to understand critical care survivors' experience of the post-intensive care syndrome (PICS). Methods: This was a meta-synthesis of primary studies that used qualitative methods. We reviewed 26 qualitative studies on PICS selected from 8 international and Korean databases and from a manual search. Thomas and Harden's 3 stages (free coding, development of descriptive themes, generation of analytical themes) for thematic synthesis were utilized to analyze the collected qualitative data. Results: Four descriptive themes emerged from the thematic synthesis: weak physical conditions, psycho-emotional changes, the painful-memory of intensive care units, and social vulnerability. The analytical theme for the current study was "unfamiliarity with the vulnerable self." Critical care survivors had to confront entirely different "selves" after discharge from intensive care units. They had become physically weak, psychologically unstable, and the critical memories continued to create distress. These changes increased their social vulnerability by making them dependent on others, causing family conflicts, and changing interpersonal relationships. Conclusions: Finding from this qualitative synthesis and other related literature highlight the severity of PICS and the importance of rehabilitative intervention for critical care survivors.

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Ginsenoside Rp1 Exerts Anti-inflammatory Effects via Activation of Dendritic Cells and Regulatory T Cells

  • Bae, Jin-Gyu;Koo, Ji-Hye;Kim, Soo-Chan;Park, Tae-Yoon;Kim, Mi-Yeon
    • Journal of Ginseng Research
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    • v.36 no.4
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    • pp.375-382
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    • 2012
  • Ginsenoside Rp1 (G-Rp1) is a saponin derivate that provides anti-metastatic activities through inhibition of the NF-${\kappa}B$ pathway. In this study, we examined the effects of G-Rp1 on regulatory T cell (Treg) activation. After treatment of splenocytes with G-Rp1, Tregs exhibited upregulation of IL-10 expression, and along with dendritic cells (DCs), these Tregs showed increased cell number compared to other cell populations. The effect of G-Rp1 on Treg number was augmented in the presence of lipopolysaccharide (LPS), which mimics pathological changes that occur during inflammation. However, depletion of DCs prevented the increase in Treg number in the presence of G-Rp1 and/or LPS. In addition, G-Rp1 promoted the differentiation of the memory types of $CD4^+Foxp3^+CD62L^{low}$ Tregs rather than the generation of new Tregs. In vivo experiments also demonstrated that Tregs and DCs from mice that were fed G-Rp1 for 7 d and then injected with LPS exhibited increased activation compared with those from mice that were injected with LPS alone. Expression of TGF-${\beta}$ and CTLA4 in Tregs was increased, and upregulation of IL-2 and CD80/CD86 expression by DCs affected the suppressive function of Tregs through IL-2 receptors and CTLA4. These data demonstrate that G-Rp1 exerts anti-inflammatory effects by activating Tregs in vitro and in vivo.

A Secure Technique Design for Privacy Protection in RFID System (RFID 시스템에서 프라이버시 보호를 위한 보안기법 설계)

  • Oh, Gi-Oug;Park, Mi-Og
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.8
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    • pp.107-115
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    • 2010
  • RFID (Radio Frequency IDentification) technology, automatic identification and data capture technologies in ubiquitous computing is an essential skill. Low-cost Radio Frequency Identification tags using memory and no physical contact due to the ease of use and maintenance of excellence are going to use expanded. However, it is possible to the illegal acquisition of the information between RFID tags and readers because RFID uses the RF signal, and the obtained information can be used for the purpose of location tracking and invasion of privacy. In this paper, we proposed the security scheme to protect against the illegal user location tracking and invasion of privacy. The security scheme proposed in this paper, using Gray Code and reduced the capacity of the calculation of the actual tags, However, it is impossible for the malicious attacker to track information because tag information transmitted from the reader is not fixed. Therefore, even if the tags information is obtained by a malicious way, our scheme provides more simple and safe user privacy than any other protection methods to protect user privacy, because not actual information but encrypted information is becoming exposed.

Optimization Protocol using Load Balancing for Hierarchical Wireless Sensor Network (무선센서네트워크에서 부하 균등화를 위한 클러스터링 최적화 프로토콜)

  • Choi, Hae-Won;Kim, Sang-Jin;Pye, Su-Young;Chang, Chu-Seock
    • Journal of Digital Convergence
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    • v.11 no.10
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    • pp.419-429
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    • 2013
  • The Wireless sensor network(WSN) consisting of a large number of sensors aims to gather data in a variety of environments. The sensor nodes operate on battery of limited power. so, To extend network life time is major goals of research in the WSN. In this paper, we state the key point of a energy consumption with minimum&load balancing. The proposed protocol guarantee balance of number of cluster member nodes using the node memory threshold and optimization of distribution of cluster head using the optimized clustering method. The results show that the proposed protocol could support the load balancing and high energy efficiency by distributing the clusters with a reasonable number of member nodes. The simulation results show that our schme ensure longer life time in WSN as compare with existing schemes such as LEACH and CBLM.

A Resource-Aware Mapping Algorithm for Coarse-Grained Reconfigurable Architecture Using List Scheduling (리스트 스케줄링을 통한 Coarse-Grained 재구성 구조의 맵핑 알고리즘 개발)

  • Kim, Hyun-Jin;Hong, Hye-Jeong;Kim, Hong-Sik;Kang, Sung-Ho
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.6
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    • pp.58-64
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    • 2009
  • For the success of the reconfigurable computing, the algorithm for mapping operations onto coarse-grained reconfigurable architecture is very important. This paper proposes a resource-aware mapping system for the coarse-grained reconfigurable architecture and its own underlying heuristic algorithm. The operation assignment and the routing path allocation are simultaneously performed with a cycle-accurate time-exclusive resource model. The proposed algorithm minimizes the communication resource usage and the global memory access with the list scheduling heuristic. The operation to be mapped are prioritized with general properties of data flow. The evaluations of the proposed algorithm show that the performance is significantly enhanced in several benchmark applications.

A Low Memory Bandwidth Motion Estimation Core for H.264/AVC Encoder Based on Parallel Current MB Processing (병렬처리 기반의 H.264/AVC 인코더를 위한 저 메모리 대역폭 움직임 예측 코어설계)

  • Kim, Shi-Hye;Choi, Jun-Rim
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.48 no.2
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    • pp.28-34
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    • 2011
  • In this paper, we present integer and fractional motion estimation IP for H.264/AVC encoder by hardware-oriented algorithm. In integer motion engine, the reference block is used to share for consecutive current macro blocks in parallel processing which exploits data reusability and reduces off-chip bandwidth. In fractional motion engine, instead of two-step sequential refinement, half and quarter pel are processed in parallel manner in order to discard unnecessary candidate positions and double throughput. The H.264/AVC motion estimation chip is fabricated on a MPW(Multi-Project Wafer) chip using the chartered $0.18{\mu}m$ standard CMOS 1P5M technology and achieves high throughput supporting HDTV 720p 30 fps.

A Study on Fault Tolerance System for Flight Control Computer and Memory of Small Drones (소형 드론용 비행 제어기 및 메모리를 위한 고장 감내 시스템 연구)

  • Lee, Jeongdu;Cho, Doosan
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.1
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    • pp.425-431
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    • 2020
  • The market for small unmanned aerial vehicles (SUAVs) is growing rapidly as technology advances and makes it possible to use them in various fields. However, due to the rapid increase in small drones, breakdowns, collisions and falls are also increasing year by year, and technologies for reducing accident and securing safety are being actively researched. In particular, the application of a fault tolerance system to cope with unexpected failures during flight is essential. According to data released by the US Department of Defense, accidents caused by errors in flight control computers account for about 28% of all accidents. This paper describes the proposal of flight control computer system's dual structure design to tolerate flight control system failure.