• 제목/요약/키워드: data locality

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Feature Extraction via Sparse Difference Embedding (SDE)

  • Wan, Minghua;Lai, Zhihui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권7호
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    • pp.3594-3607
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    • 2017
  • The traditional feature extraction methods such as principal component analysis (PCA) cannot obtain the local structure of the samples, and locally linear embedding (LLE) cannot obtain the global structure of the samples. However, a common drawback of existing PCA and LLE algorithm is that they cannot deal well with the sparse problem of the samples. Therefore, by integrating the globality of PCA and the locality of LLE with a sparse constraint, we developed an improved and unsupervised difference algorithm called Sparse Difference Embedding (SDE), for dimensionality reduction of high-dimensional data in small sample size problems. Significantly differing from the existing PCA and LLE algorithms, SDE seeks to find a set of perfect projections that can not only impact the locality of intraclass and maximize the globality of interclass, but can also simultaneously use the Lasso regression to obtain a sparse transformation matrix. This characteristic makes SDE more intuitive and more powerful than PCA and LLE. At last, the proposed algorithm was estimated through experiments using the Yale and AR face image databases and the USPS handwriting digital databases. The experimental results show that SDE outperforms PCA LLE and UDP attributed to its sparse discriminating characteristics, which also indicates that the SDE is an effective method for face recognition.

제주지역 현대건축의 배치계획특성에 관한 연구 -국내 및 제주의 문화·집회시설에 관한 비교분석을 중심으로- (A Study on the Site Plan of the Contemporary Architecture in Jeju -Focused on the Comparative Study of Culture and Meeting Facilities in Domestic and Jeju-)

  • 홍광택;박정근
    • 한국농촌건축학회논문집
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    • 제12권2호
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    • pp.117-124
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    • 2010
  • This study has the purpose to examine the elements of deducing site plan of contemporary architecture in Jeju by looking into the mainly used measures and value in establishing the site plan of contemporary architecture of Jeju. Being the initial decision making stage that serves as basis in creating design alternative and completes overall designing alternative frame, Site plan is the core stage of initial architectural planning. In addition, analysis of site plan concept the central overall idea for site plan offers the perspective to access the problem for solution in site plan. Therefore, through the analysis of elements to deduce the site plan concept of the contemporary architecture in Jeju, the characteristics of site plan concept that considered the placement and locality of Jeju can be objectively examined in planning out the site plan of contemporary architecture in Jeju, and such analysis results may become objective basic data in planning out the site plan of the contemporary architecture in Jeju.

개선된 가역 워터마킹 알고리즘 (An Advanced Watermarking Algorithm with Reversibility)

  • 정수목
    • 한국융합학회논문지
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    • 제9권2호
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    • pp.151-156
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    • 2018
  • 본 논문에서는 효율적인 가역 워터마킹 알고리즘을 제안하였다. 제안된 기법을 사용하여, 커버 이미지에 은닉할 수 있는 저작권관련 정보의 양을 증가시킬 수 있다. 공간적 지역성과 표면 특성에 따라, 주변 픽셀들을 사용하여 픽셀 값을 정밀하게 예측할 수 있다. 예측된 픽셀 값과 커버 이미지의 원본 픽셀 값이 거의 같게 되면, 커버 이미지의 원본 픽셀 값과 예측 픽셀 값의 차이가 매우 적게 된다. 그러므로 차분 시퀀스에 대한 히스토그램의 피크 포인트에서의 빈도수가 크게 증가하게 된다. 따라서 커버 이미지에 은닉할 수 있는 기밀 데이터의 양이 크게 증가하게 된다. 실험 결과를 통하여 제안된 워터마킹 알고리즘이 기존의 알고리즘보다 우수함을 확인 할 수 있다.

국내 지역성을 고려한 전단파속도와 대표지층의 상관관계 분석 (Analysis of Local Correlation between Shear Wave Velocity and Geo-layer in Korea)

  • 김한샘;최승호;정충기
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.687-698
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    • 2010
  • Borehole drilled depend on the point is bound to be limited to obtain the 2-D or 3-D layer information for entire targer area. On the other hand, SASW and MASW provide the sectional form of layer information through the shear wave velocity($V_s$). Therefore the useful information of the target area can be derived from SASW, MASW and borehole data. In this research, the correlation reflected locality and nationwide between sectional geo-layer and $V_s$ was investigated and analyzed. The target areas are westside of Pyeongtaek and Incheon. The shear wave velocity($V_s$) obtained from SASW, MASW and borehole data conducted within the scope of crossline for survey was utilized in each region. In the 2D distribution of $V_s$ from SASW, MASW, $V_s$ tend to continually increase deeper and deeper. By the target area, the depth of each representative geo-layer was nested on the sectional distribution map of $V_s$ to suggest the range of $V_s$ in accordance of strata by using borehole data. The 2D sectional geo-layer distribution map is presented based on the range of $V_s$. In addition the correlation between measured and calculated $V_s$ according to the empirical equation was analyzed.

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여름철 한반도 강수의 시·공간적 특성 연구 (Study on Temporal and Spatial Characteristics of Summertime Precipitation over Korean Peninsula)

  • 인소라;한상옥;임은순;김기훈;심재관
    • 대기
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    • 제24권2호
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    • pp.159-171
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    • 2014
  • This study investigated the temporal and spatial characteristics of summertime (June-August) precipitation over Korean peninsula, using Korea Meteorological Administration (KMA)is Automated Synoptic Observing System (ASOS) data for the period of 1973-2010 and Automatic Weather System (AWS) data for the period of 1998-2010.The authors looked through climatological features of the summertime precipitation, then examined the degree of locality of the precipitation, and probable precipitation amount and its return period of 100 years (i.e., an extreme precipitation event). The amount of monthly total precipitation showed increasing trends for all the summer months during the investigated 38-year period. In particular, the increasing trends were more significant for the months of July and August. The increasing trend of July was seen to be more attributable to the increase of precipitation intensity than that of frequency, while the increasing trend of August was seen to be played more importantly by the increase of the precipitation frequency. The e-folding distance, which is calculated using the correlation of the precipitation at the reference station with those at all other stations, revealed that it is August that has the highest locality of hourly precipitation, indicating higher potential of localized heavy rainfall in August compared to other summer months. More localized precipitation was observed over the western parts of the Korean peninsula where terrain is relatively smooth. Using the 38-years long series of maximum daily and hourly precipitation as input for FARD2006 (Frequency Analysis of Rainfall Data Program 2006), it was revealed that precipitation events with either 360 mm $day^{-1}$ or 80 mm $h^{-1}$ can occur with the return period of 100 years over the Korean Peninsula.

A Locality-Aware Write Filter Cache for Energy Reduction of STTRAM-Based L1 Data Cache

  • Kong, Joonho
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권1호
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    • pp.80-90
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    • 2016
  • Thanks to superior leakage energy efficiency compared to SRAM cells, STTRAM cells are considered as a promising alternative for a memory element in on-chip caches. However, the main disadvantage of STTRAM cells is high write energy and latency. In this paper, we propose a low-cost write filter (WF) cache which resides between the load/store queue and STTRAM-based L1 data cache. To maximize efficiency of the WF cache, the line allocation and access policies are optimized for reducing energy consumption of STTRAM-based L1 data cache. By efficiently filtering the write operations in the STTRAM-based L1 data cache, our proposed WF cache reduces energy consumption of the STTRAM-based L1 data cache by up to 43.0% compared to the case without the WF cache. In addition, thanks to the fast hit latency of the WF cache, it slightly improves performance by 0.2%.

프로세싱 인 메모리 시스템에서의 PolyBench 구동에 대한 동작 성능 및 특성 분석과 고찰 (Performance Analysis and Identifying Characteristics of Processing-in-Memory System with Polyhedral Benchmark Suite)

  • 김정근
    • 반도체디스플레이기술학회지
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    • 제22권3호
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    • pp.142-148
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    • 2023
  • In this paper, we identify performance issues in executing compute kernels from PolyBench, which includes compute kernels that are the core computational units of various data-intensive workloads, such as deep learning and data-intensive applications, on Processing-in-Memory (PIM) devices. Therefore, using our in-house simulator, we measured and compared the various performance metrics of workloads based on traditional out-of-order and in-order processors with Processing-in-Memory-based systems. As a result, the PIM-based system improves performance compared to other computing models due to the short-term data reuse characteristic of computational kernels from PolyBench. However, some kernels perform poorly in PIM-based systems without a multi-layer cache hierarchy due to some kernel's long-term data reuse characteristics. Hence, our evaluation and analysis results suggest that further research should consider dynamic and workload pattern adaptive approaches to overcome performance degradation from computational kernels with long-term data reuse characteristics and hidden data locality.

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LAN 환경에서의 트래픽 해석에 관한 연구 (A study on the traffic analysis in LAN environment)

  • 이종영;오영환
    • 한국통신학회논문지
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    • 제21권8호
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    • pp.1970-1975
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    • 1996
  • The characteristics of data traffic on the Ethernet LAN are investigated on the basis of measurements. The analysis on the arrival pattern of packets on the network is found not to be a Poission process but to be Weibull distributions. An analysis of network traffic, packet arrivals are found to exhibit a 'source locality'. It is observed that file transfers are reponsible for about 92% of the traffic on the network. Our results will be useful for modelling purposes.

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제주도근해의 한국 미기록 흑갯민숭이류 4종에 관한 종내색채변이와 분포범위 (Unrecorded Phyllidiid Nudibranchs from Cheju Island Waters in Korea with Remarks on New Locality Data and Intraspecific Color Variations)

  • Choe, Byung-Lae;Lee, Jongrak
    • 한국패류학회지
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    • 제13권1호
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    • pp.37-42
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    • 1997
  • 1990년 12월부터 1997년 7월까지 제주도의 8개 지점에서 4종(Phyllidia ocellata, Fryeria menindie, Phyllidiella pustulosa, Phyllidiella cooraburrama)의 혹갯민숭이과가 채집되어 이들의 색채변이 및 분포범위에 대하여 논하였다. 또한 원색 사진과 함께 재기재를 하였다. 혹갯민숭이류는 한국해역에서 새로이 기록되는 과이다.

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A Sector-Labeling for generating the Hilbert Space-filling Curve and Its Intention

  • Slamet, Santosa;Naoi, Tohru
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -1
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    • pp.38-41
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    • 2002
  • Many scientifc applications include manipulation of data points tying in a space. We describe a method, based on sector labeling to generate a space-filling curve for partitioning such given data points. Our method is straightforward and flexible, equipping a one-one correspondence between point-values on the curve and data points in space in more efficient than designated methods found in the literature. It is widely believed that the Hilbert curve achieves the desired properties on linear mappings due to the locality between data points. Therefore we focus on the Hilbert curve since, later on, we identify it as the most suitable for our application. We demonstrate on using our method for the data particles of an n-body simulation that based on Barnes-Hut algorithm.

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