• Title/Summary/Keyword: Data compression

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Design of 32-bit Floating Point Multiplier for FPGA (FPGA를 위한 32비트 부동소수점 곱셈기 설계)

  • Xuhao Zhang;Dae-Ik Kim
    • The Journal of the Korea institute of electronic communication sciences
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    • v.19 no.2
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    • pp.409-416
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    • 2024
  • With the expansion of floating-point operation requirements for fast high-speed data signal processing and logic operations, the speed of the floating-point operation unit is the key to affect system operation. This paper studies the performance characteristics of different floating-point multiplier schemes, completes partial product compression in the form of carry and sum, and then uses a carry look-ahead adder to obtain the result. Intel Quartus II CAD tool is used for describing Verilog HDL and evaluating performance results of the floating point multipliers. Floating point multipliers are analyzed and compared based on area, speed, and power consumption. The FMAX of modified Booth encoding with Wallace tree is 33.96 Mhz, which is 2.04 times faster than the booth encoding, 1.62 times faster than the modified booth encoding, 1.04 times faster than the booth encoding with wallace tree. Furthermore, compared to modified booth encoding, the area of modified booth encoding with wallace tree is reduced by 24.88%, and power consumption of that is reduced by 2.5%.

Fat Quantification in the Vertebral Body: Comparison of Modified Dixon Technique with Single-Voxel Magnetic Resonance Spectroscopy

  • Sang Hyup Lee;Hye Jin Yoo;Seung-Man Yu;Sung Hwan Hong;Ja-Young Choi;Hee Dong Chae
    • Korean Journal of Radiology
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    • v.20 no.1
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    • pp.126-133
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    • 2019
  • Objective: To compare the lumbar vertebral bone marrow fat-signal fractions obtained from six-echo modified Dixon sequence (6-echo m-Dixon) with those from single-voxel magnetic resonance spectroscopy (MRS) in patients with low back pain. Materials and Methods: Vertebral bone marrow fat-signal fractions were quantified by 6-echo m-Dixon (repetition time [TR] = 7.2 ms, echo time (TE) = 1.21 ms, echo spacing = 1.1 ms, total imaging time = 50 seconds) and single-voxel MRS measurements in 25 targets (23 normal bone marrows, two focal lesions) from 24 patients. The point-resolved spectroscopy sequence was used for localized single-voxel MRS (TR = 3000 ms, TE = 35 ms, total scan time = 1 minute 42 seconds). A 2 × 2 × 1.5 cm3 voxel was placed within the normal L2 or L3 vertebral body, or other lesions including a compression fracture or metastasis. The bone marrow fat spectrum was characterized on the basis of the magnitude of measurable fat peaks and a priori knowledge of the chemical structure of triglycerides. The imaging-based fat-signal fraction results were then compared to the MRS-based results. Results: There was a strong correlation between m-Dixon and MRS-based fat-signal fractions (slope = 0.86, R2 = 0.88, p < 0.001). In Bland-Altman analysis, 92.0% (23/25) of the data points were within the limits of agreement. Bland-Altman plots revealed a slight but systematic error in the m-Dixon based fat-signal fraction, which showed a prevailing overestimation of small fat-signal fractions (< 20%) and underestimation of high fat-signal fractions (> 20%). Conclusion: Given its excellent agreement with single-voxel-MRS, 6-echo m-Dixon can be used for visual and quantitative evaluation of vertebral bone marrow fat in daily practice.

Adaptive Data Hiding Techniques for Secure Communication of Images (영상 보안통신을 위한 적응적인 데이터 은닉 기술)

  • 서영호;김수민;김동욱
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.5C
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    • pp.664-672
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    • 2004
  • Widespread popularity of wireless data communication devices, coupled with the availability of higher bandwidths, has led to an increased user demand for content-rich media such as images and videos. Since such content often tends to be private, sensitive, or paid for, there exists a requirement for securing such communication. However, solutions that rely only on traditional compute-intensive security mechanisms are unsuitable for resource-constrained wireless and embedded devices. In this paper, we propose a selective partial image encryption scheme for image data hiding , which enables highly efficient secure communication of image data to and from resource constrained wireless devices. The encryption scheme is invoked during the image compression process, with the encryption being performed between the quantizer and the entropy coder stages. Three data selection schemes are proposed: subband selection, data bit selection and random selection. We show that these schemes make secure communication of images feasible for constrained embed-ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of ded devices. In addition we demonstrate how these schemes can be dynamically configured to trade-off the amount of data hiding achieved with the computation requirements imposed on the wireless devices. Experiments conducted on over 500 test images reveal that, by using our techniques, the fraction of data to be encrypted with our scheme varies between 0.0244% and 0.39% of the original image size. The peak signal to noise ratios (PSNR) of the encrypted image were observed to vary between about 9.5㏈ to 7.5㏈. In addition, visual test indicate that our schemes are capable of providing a high degree of data hiding with much lower computational costs.

Geological Structure of the Metamorphic Rocks in the Muju-Seolcheon Area, Korea: Consideration on the Boundary of Ogcheon Belt and Ryeongnam Massif (무주-설천 지역 변성암류의 지질구조: 옥천벨트와 영남육괴의 경계부 고찰)

  • Kang, Ji-Hoon
    • The Journal of the Petrological Society of Korea
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    • v.28 no.1
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    • pp.25-38
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    • 2019
  • The Muju-Seolcheon area, which is known to be located in the boundary of Ogcheon Belt and Ryeongnam Massif (OB-RM), consists of age unknown or Precambrian metamorphic rocks (MRs) [banded biotite gneiss, metasedimentary rocks (black phyllite, mica schist, crystalline limestone, quartzite), granitic gneiss, hornblendite], Mesozoic sedimentary and igneous rocks. In this paper are researched the structural characteristics of each deformation phase from the geometric and kinematic features and the developing sequence of multi-deformed rock structures of the MRs, and is considered the boundary location of OB-RM with the previous geochemical, radiometric, structure geological data. The geological structure of this area is at least formed through four phases (Dn-1, Dn, Dn+1, Dn+2) of deformation. The Dn-1 is the deformation which took place before the formation of Sn regional foliation and formed Sn-1 foliation folded by Fn fold. The Dn is that which formed the Sn regional foliation. The predominant Sn foliation shows a NE direction which matches the zonal distribution of MRs. A-type or sheath folds, in which the Fn fold axis is parallel to the direction of stretching lineation, are often observed in the crystalline limestone. The Dn+1 deformation, which folded the Sn foliation, took place under compression of NNW~NS direction and formed Fn+1 fold of ENE~EW trend. The Sn foliation is mainly rearranged by Fn+1 folding, and the ${\pi}$-axis of Sn foliation, which is dispersed, shows the nearly same direction as the predominant Fn+1 fold axis. The Dn+2 deformation, which folded the Sn and Sn+1 foliations, took place under compression of E-W direction, and formed open folds of N-S trend. And the four phases of deformation are recognized in all domains of the OB-RM, and the structural characteristics and differences to divide these tectonic provinces can not be observed in this area. According to the previous geochemical and radiometric data, the formation or metamorphic ages of the MRs in and around this area were Middle~Late Paleproterozoic. It suggests that the crystalline limestone was at least deposited before Middle Paleproterozoic. This deposition age is different in the geologic age of Ogcheon Supergroup which was recently reported as Neoproterozoic~Late Paleozoic. Therefore, the division of OB-RM tectonic provinces in this area, which regards the metasedimentary rocks containing crystalline limestone as age unknown Ogcheon Group, is in need of reconsideration.

Case Study on the Instability of the Slopes in Unsaturated Residual Soils Considering the Rainfall Characteristics (강우특성을 고려한 불포화 잔적토 비탈면의 붕괴사례 연구)

  • Nam, Samheon;Lee, Younghuy;Oh, Seboong
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.1
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    • pp.45-53
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    • 2015
  • This study has obtained Soil Water Retention Curve (SWRC) of the unsaturated soil from the volumetric pressure plate extractor test and the triaxial compression tests was also conducted. By using the rainfall data measured in the site the seepage analysis of unsteady flow was performed with the program of SEEP/W in Geostudio 2007 and stability of the slope was analyzed with SLOPE/W program. Results of analyses show that shear strength of the unsaturated soil increases with the increase of matric suction. And it was also found that the net volumetric stress and the apparent cohesion increased with the matric suction. The seepage analysis of rainfall represents that the increasing rate of negative pore pressure at the zone of large negative pore pressure is appeared to be high even though lower rainfall intensity, but this tendency declines with ground depth. The stability analysis of slope was carried out for the actual plane of failure with the data representing the field condition. The factor of safety thus calculated was about unity (1.0) or just below, which means that the adopted method of analysis is in good agreement with the field condition.

Research on Planning and Design of Smart Fitness Wear for Personal Training Improvement (퍼스널 트레이닝 효과 향상을 위한 스마트 피트니스웨어의 상품기획 및 디자인 방향 연구)

  • Jung, Chanwoong;Kwak, Yonghoo;Park, Seoyeon;Lee, Joohyeon
    • Science of Emotion and Sensibility
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    • v.20 no.3
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    • pp.97-108
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    • 2017
  • The purpose of this study was to propose a product planning and design direction for smart fitness wear that will improve the impact of personal training based on researching the requirements of smart fitness wear and its acceptance level, as well as the functional demand. The study conducted in-depth interviews with professional fitness trainers and derived five categories and thirteen keywords by analyzing the categorical data analysis using the interview data. In addition, we surveyed general consumers to measure the acceptance level of smart fitness wear and the functional demand for product development. The results revealed that the difference in the acceptance level of smart fitness wear generally depended on the characteristics related to exercise involvement and exercise-related culture rather than on the demographic characteristics. With regard to the difference in the functional demand of smart fitness wear, the results showed that professional trainers focused on the scientific improvement of the effect of exercise while general consumers focused on the function that considers the sustainability of exercise. Based on the results, we proposed product planning and design directions such as 'mounting of heart rate sensing, muscle activity sensing, motion angle or posture sensing, and motion sensing', 'development of concepts and contents for expert line, ordinary line', 'compression wear design', and 'differentiation of product development according to exercise areas'.

The effects on fatigue and accuracy of cardiopulmonary resuscitation of the verbal-order method based on different time intervals (3, 4 minutes) (시간 (3분, 4분)에 따른 구령방법이 심폐소생술의 피로도와 정확도에 미치는 영향)

  • Lee, Mi Kyoung;Yang, Jeong Ok;Jung, Joo Ha;Lee, Kyeong Jun;Cho, Youngseuk
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.2
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    • pp.409-417
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    • 2016
  • The purpose of this study was to demonstrate the effect on the degree of fatigue and accuracy of cardiopulmonary resuscitation according to the different time delays (3 minutes, 4 minutes). Carrying out repeated measures of variance (repeated ANOVA), we have shown that time effect (F = 7.835, p <.01) and group effect (F = 8.695, p<.01) and the interaction effect between time and group (F = 12.582, p<.001) were all statistically significant. It means, in the test of the main effect of group and time (3 minutes, 4 minutes) using the Bonferroni method, it turned out that the amount of lactic acid of the experimental group was larger than that of the control group (p<.01), and there was no difference until 3 minutes, but the difference of the amount of lactic acid was shown between before the experiment and after 4 minutes, and between 3 minutes and 4 minutes (p <.05), respectively. Then, in the result of the corresponding sample t-test, for comparing the according to the measurement time, the accuracy after 3 minutes became higher than the case of 4 minutes (t = 4.584, p <.001). Therefore, before 119 arrives performing cardiopulmonary resuscitation for emergency, rescuers need to perform cardiopulmonary resuscitation alternating with others before 3 minutes.

Stress Analysis of an Edge-Cracked Plate by using Photoelastic Fringe Phase Shifting Method (광탄성프린지 위상이동법을 이용한 에지균열판의 응력 해석)

  • Baek, Tae-Hyun;Kim, Myung-Soo;Cho, Sung-Ho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.20 no.3
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    • pp.213-220
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    • 2000
  • The method of photoelasticity allows one to obtain principal stress differences and principal stress directions in a photoelastic model. In the classical approach, the photoelastic parameters are measured manually point by point. The previous methods require much time and skill in the identification and measurement of photoelastic data. Fringe phase shifting method has been recently developed and widely used to measure and analyze fringe data in photo-mechanics. This paper presents the test results of photoelastic fringe phase shifting technique for the stress analysis of a circular disk under compression and an edge-cracked plate subjected to tensile load. The technique used here requires four phase stepped photoelastic images obtained from a circular polariscope by rotating the analyzer at $0^{\circ}$, $45^{\circ}$, $90^{\circ}$ and $135^{\circ}$. Experimental results are compared with those or FEM. Good agreement between the results can be observed. However, some error may be included if the technique is used to general direction which is not parallel to isoclinic fringe.

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Bone Mineral Density of Normal Korean Adult Using QCT (적량적 전산화단층촬영을 이용한 한국인의 골밀도)

  • Lee Jong Deok
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.6
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    • pp.1918-1926
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    • 2004
  • Osteoporosis is defined as a progressive systemic skeletal disorder characterized by low bone mineral density, microarchitectual deteriorations of bone and susceptibility to fracture. numerous methods have been used for quantitative assessment of the skeleton in osteoporosis. QCT has been shown to measure changes in trabecular mineral content in the spine with great sensitivity and precision. To provide the normal reference values and changes of lumbar spinal bone mineral density in korean adult spinal bone mineral density was evaluated in 451 women (229 premenopausal and 222 postmenopausal women) and 206 men, aged 20 to 74 years old in Wonkwang hospital from 2000 to 2004, which was carried out by using QCT. women with oophorectomy, vertebral compression fracture, any history of endocrine disease and use of drugs that alter bone metabolism were excluded. According to the WHO definition, a patient is osteoporotic based on a bone mineral density(BMD) measurement that is 2.5 standard deviations (SDs) below typical peak bone mass of young healthy white women. This measurement of standard deviation from peak mass is called the T score. BMD values of normal women in their 20-24 years, 25-29 years, 30-34 years, 35-39 years, 40-44 years, 45-49 years, 50-54 years, 55-59 years, 60-64 years, 65-69 years, over 70 years were 168.95㎎/㏄ K₂PHO₄, 155.41㎎/㏄ K₂PHO₄, 166.87㎎/㏄ K₂PHO₄, 160.67㎎/㏄ K₂PHO₄, 154.06㎎/㏄ K₂PHO₄, 132.04㎎/㏄ K₂PHO₄, 114.05㎎/㏄ K₂PHO₄, 91.78㎎/㏄ K₂PHO₄, 78.61 ㎎/㏄ K₂PHO₄, 61.35㎎/㏄ K₂PHO₄, 50.53㎎/㏄ K₂PHO₄ Mean bone density of normal women was 115.77K₂PHO₄ K₂PHO₄. BMD values of normal men in their 20-24 years, 25-29 years, 30-34 years, 35-39 years, 40-44 years, 45-49 years, 50-54 years, 55-59 years, 60-64 years, 65-69 years, over 70 years were 171.46㎎/㏄ K₂PHO₄, 162.19㎎/㏄ K₂PHO₄, 155.62㎎/㏄ K₂PHO₄, 147.28㎎/㏄ K₂PHO₄, 137.56㎎/㏄ K₂PHO₄, 137.56㎎/㏄ K₂PHO₄, 101.25㎎/㏄ K₂PHO₄, 109.00㎎/㏄ K₂PHO₄, 103.32㎎/㏄ K₂PHO₄, 91.53㎎/㏄ K₂PHO₄, 88.35㎎/㏄ K₂PHO₄ Mean density of normal men was 115.77㎎/㏄ K₂PHO₄. Peak bone density of women and men was in the age group of 20-24 years and 168.95㎎/㏄ K₂PHO₄, 171.46㎎/㏄ K₂PHO₄, respectively. Bone loss was increased with aging and was accelerated in postmenopausal women than that of premenopausal women. The total loss of BMD for women and men was 70.09% and 48.47%, respectively. Postmenopausal women(mean BMD : 85.83㎎/㏄ K₂PHO₄) had significantly lower BMD than premenopausal women(meand BMD : 144.80㎎/㏄ K₂PHO₄)(p<0.001). The annual loss of BMD of women and men was 2.702㎎/㏄ K₂PHO₄ and 1.795㎎/㏄ K₂PHO₄, respectively. This study provided the BMD reference data for normal korean adult. further studies on BMD in healthy adult and comparison with published data are needed.

Design and Implementation of An I/O System for Irregular Application under Parallel System Environments (병렬 시스템 환경하에서 비정형 응용 프로그램을 위한 입출력 시스템의 설계 및 구현)

  • No, Jae-Chun;Park, Seong-Sun;;Gwon, O-Yeong
    • Journal of KIISE:Computer Systems and Theory
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    • v.26 no.11
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    • pp.1318-1332
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    • 1999
  • 본 논문에서는 입출력 응용을 위해 collective I/O 기법을 기반으로 한 실행시간 시스템의 설계, 구현 그리고 그 성능평가를 기술한다. 여기서는 모든 프로세서가 동시에 I/O 요구에 따라 스케쥴링하며 I/O를 수행하는 collective I/O 방안과 프로세서들이 여러 그룹으로 묶이어, 다음 그룹이 데이터를 재배열하는 통신을 수행하는 동안 오직 한 그룹만이 동시에 I/O를 수행하는 pipelined collective I/O 등의 두 가지 설계방안을 살펴본다. Pipelined collective I/O의 전체 과정은 I/O 노드 충돌을 동적으로 줄이기 위해 파이프라인된다. 이상의 설계 부분에서는 동적으로 충돌 관리를 위한 지원을 제공한다. 본 논문에서는 다른 노드의 메모리 영역에 이미 존재하는 데이터를 재 사용하여 I/O 비용을 줄이기 위해 collective I/O 방안에서의 소프트웨어 캐슁 방안과 두 가지 모형에서의 chunking과 온라인 압축방안을 기술한다. 그리고 이상에서 기술한 방안들이 입출력을 위해 높은 성능을 보임을 기술하는데, 이 성능결과는 Intel Paragon과 ASCI/Red teraflops 기계 상에서 실험한 것이다. 그 결과 응용 레벨에서의 bandwidth는 peak point가 55%까지 측정되었다.Abstract In this paper we present the design, implementation and evaluation of a runtime system based on collective I/O techniques for irregular applications. We present two designs, namely, "Collective I/O" and "Pipelined Collective I/O". In the first scheme, all processors participate in the I/O simultaneously, making scheduling of I/O requests simpler but creating a possibility of contention at the I/O nodes. In the second approach, processors are grouped into several groups, so that only one group performs I/O simultaneously, while the next group performs communication to rearrange data, and this entire process is pipelined to reduce I/O node contention dynamically. In other words, the design provides support for dynamic contention management. Then we present a software caching method using collective I/O to reduce I/O cost by reusing data already present in the memory of other nodes. Finally, chunking and on-line compression mechanisms are included in both models. We demonstrate that we can obtain significantly high-performance for I/O above what has been possible so far. The performance results are presented on an Intel Paragon and on the ASCI/Red teraflops machine. Application level I/O bandwidth up to 55% of the peak is observed.he peak is observed.