• Title/Summary/Keyword: multiple blocks

Search Result 258, Processing Time 0.024 seconds

Multiple Approaches and Participation Rate for a Community Based Smoking Cessation Intervention Trial in Rural Kerala, India

  • Jayakrishnan, Radhakrishnan;Mathew, Aleyamma;Uutela, Antti;Auvinen, Anssi;Sebastian, Paul
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.5
    • /
    • pp.2891-2896
    • /
    • 2013
  • Background: To illustrate multiple approaches and to assess participation rates adopted for a community based smoking cessation intervention programme in rural Kerala. Materials and Methods: Resident males in the age group 18-60 years who were 'current daily smokers' from 4 randomly allocated community development blocks of rural Thiruvananthapuram district, Kerala (2 intervention and 2 control groups) were selected. Smoking status was assessed through house-to-house survey using trained volunteers. Multiple approaches included awareness on tobacco hazards during baseline survey and distribution of multicolour anti-tobacco leaflets for intervention and control groups. Further, the intervention group received a tobacco cessation booklet and four sessions of counselling which included a one-time group counselling cum medical camp, followed by proactive counselling through face-to-face (FTF) interview and mobile phone. In the second and fourth session, motivational counselling was conducted. Results: Among 928 smokers identified, smokers in intervention and control groups numbered 474 (mean age: 44.6 years, SD: 9.66 years) and 454 respectively (44.5 years, SD: 10.30 years). Among the 474 subjects, 75 (16%) had attended the group counselling cum medical camp after completion of baseline survey in the intervention group, Among the remaining subjects (n=399), 88% were contacted through FTF and mobile phone (8.5%). In the second session (4-6 weeks time period), the response rate for individual counselling was 94% (78% through FTF and 16% through mobile phone). At 3 months, 70.4% were contacted by their mobile phone and further, 19.6% through FTF (total 90%) while at 6 months (fourth session), the response rate was 74% and 16.4% for FTF and mobile phone respectively, covering 90.4% of the total subjects. Overall, in the intervention group, 97.4% of subjects were being contacted at least once and individual counselling given. Conclusion: Proactive community centred intervention programmes using multiple approaches were found to be successful to increase the participation rate for intervention.

Opto-Digital Implementation of Multiple Information Hiding & Real-time Extraction System (다중 정보 은폐 및 실시간 추출 시스템의 광-디지털적 구현)

  • 김정진;최진혁;김은수
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.28 no.1C
    • /
    • pp.24-31
    • /
    • 2003
  • In this paper, a new opto-digital multiple information hiding and real-time extracting system is implemented. That is, multiple information is hidden in a cover image by using the stego keys which are generated by combined use of random sequence(RS) and Hadamard matrix(HM) and these hidden information is extracted in real-time by using a new optical correlator-based extraction system. In the experiment, 3 kinds of information, English alphabet of "N", "R", "L" having 512$\times$512 pixels, are formulated 8$\times$8 blocks and each of these information is multiplied with the corresponding stego keys having 64$\times$64 pixels one by one. And then, by adding these modulated data to a cover image of "Lena"having 512$\times$512 pixels, a stego image is finally generated. In this paper, as an extraction system, a new optical nonlinear joint transform correlator(NJTC) is introduced to extract the hidden data from a stego image in real-time, in which optical correlation between the stego image and each of the stego keys is performed and from these correlation outputs the hidden data can be asily exacted in real-time. Especially, it is found that the SNRs of the correlation outputs in the proposed optical NJTC-based extraction system has been improved to 7㏈ on average by comparison with those of the conventional JTC system under the condition of having a nonlinear parameter less than k=0.4. This good experimental results might suggest a possibility of implementation of an opto-digital multiple information hiding and real-time extracting system.

An Optimization Method for Hologram Generation on Multiple GPU-based Parallel Processing (다중 GPU기반 홀로그램 생성을 위한 병렬처리 성능 최적화 기법)

  • Kook, Joongjin
    • Smart Media Journal
    • /
    • v.8 no.2
    • /
    • pp.9-15
    • /
    • 2019
  • Since the computational complexity for hologram generation increases exponentially with respect to the size of the point cloud, parallel processing using CUDA and/or OpenCL library based on multiple GPUs has recently become popular. The CUDA kernel for parallelization needs to consist of threads, blocks, and grids properly in accordance with the number of cores and the memory size in the GPU. In addition, in case of multiple GPU environments, the distribution in grid-by-grid, in block-by-block, or in thread-by-thread is needed according to the number of GPUs. In order to evaluate the performance of CGH generation, we compared the computational speed in CPU, in single GPU, and in multi-GPU environments by gradually increasing the number of points in a point cloud from 10 to 1,000,000. We also present a memory structure design and a calculation method required in the CUDA-based parallel processing to accelerate the CGH (Computer Generated Hologram) generation operation in multiple GPU environments.

Globular clusters with multiple red giant branches as remaining nuclei of primeval dwarf galaxies

  • Lee, Young-Wook;Han, Sang-Il;Joo, Seok-Joo;Lim, Dongwook;Jang, Sohee;Na, Chongsam;Roh, Dong-Goo
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.38 no.2
    • /
    • pp.73.2-73.2
    • /
    • 2013
  • In the current ${\Lambda}CDM$ hierarchical merging paradigm, a galaxy like the Milky Way formed by numerous mergers of ancient subsystems. Most of the relics of these building blocks, however, are yet to be discovered or identified. Recent progress in the Milky Way globular cluster research is throwing new light on this perspective. The discoveries of multiple stellar populations having different heavy element abundances in some massive globular clusters are suggesting that they are most likely the remaining cores or relics of disrupted dwarf galaxies. In this talk, we will report our progress in the (1) narrow-band photometry, (2) low-resolution spectroscopy, and (3) population modeling for this growing group of peculiar globular clusters.

  • PDF

VLSI Architecture of General-purpose Memory Controller for Multiple Processing (다수의 프로세싱 유닛 처리를 위한 범용 메모리 제어기의 구조)

  • Lee, Yoon-Hyuk;Seo, Young-Ho;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.15 no.12
    • /
    • pp.2632-2640
    • /
    • 2011
  • In this paper, we implemented a memory controller which can accommodate data processing blocks. The memory controller is arbitrated by the internal arbiter which receives request signals from masters and sends grant and data signals to masters. The designed memory controller consists of Master Interface, Master Arbitrator, Memory Interface, Memory accelerator. It was designed using VHDL, and verified using the memory model of SAMSING Inc. For FPGA synthesis and verification, Quartus II of ATERA Inc. was used. The target device is Cyclone II. For simulation, ModelSim of Cadence Inc was used.

Digital Image Encryption Method Using Interleaving and Random Shuffling (인터리빙과 랜덤 셔플링을 이용한 디지털 영상의 암호화 방법)

  • Lee Ji-Bum;Ko Hyung-Hwa
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.31 no.5C
    • /
    • pp.497-502
    • /
    • 2006
  • In this paper, we propose a digital image encryption method using adaptive interleaving and multiple random shuffling table to improve the existing encryption methods which use a fixed random shuffling table. In order to withstand the plaintext attack, at first, we propose a interleaving method that is adaptive to the local feature of image. Secondly, using the proposed interleaving only shuffling method and multiple shuffling method that is combined interleaving with existing random shuffling method, we encrypted image by shuffled the DPCM processed $8^*8$ blocks. Experimental results show that, the proposed algorithm is very robust to plaintext attack and there is no overhead bit.

On the origin of Na-O anticorrelation in globular clusters

  • Kim, Jaeyeon;Lee, Young-Wook
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.42 no.1
    • /
    • pp.49.1-49.1
    • /
    • 2017
  • In order to investigate the origin of multiple stellar populations in the halo and bulge of the Milky Way, we have constructed chemical evolution models for the low-mass proto-Galactic subsystems such as globular clusters (GCs). Unlike previous studies, we assume that supernova blast waves undergo blowout without expelling the pre-enriched gas, while relatively slow winds of massive stars, together with the winds and ejecta from low and intermediate mass asymptotic giant branch stars, are all locally retained in these less massive systems. We first applied these models to investigate the origin of super-helium-rich red clump stars in the metal-rich bulge as recently suggested by Lee et al. (2015). We find that chemical enrichments by the winds of massive stars can naturally reproduce the required helium enhancement (dY/dZ = 6) for the second generation stars. Disruption of these "building blocks" in a hierarchical merging paradigm would have provided helium enhanced stars to the bulge field. Interestingly, we also find that the observed Na-O anticorrelation in metal-poor GCs can be reproduced, when multiple episodes of starbursts are allowed to continue in these subsystems. Specific star formation history with decreasing time intervals between the stellar generations, however, is required to obtain this result, as would be expected from the orbital evolution of these subsystems in a proto-Galaxy. The "mass budget problem" is also much alleviated by our models without ad-hoc assumptions on star formation efficiency and initial mass function.

  • PDF

Rotationally Invariant Space-Time Trellis Codes with 4-D Rectangular Constellations for High Data Rate Wireless Communications

  • Sterian, Corneliu Eugen D.;Wang, Cheng-Xiang;Johnsen, Ragnar;Patzold, Matthias
    • Journal of Communications and Networks
    • /
    • v.6 no.3
    • /
    • pp.258-268
    • /
    • 2004
  • We demonstrate rotationally invariant space-time (ST) trellis codes with a 4-D rectangular signal constellation for data transmission over fading channels using two transmit antennas. The rotational invariance is a good property to have that may alleviate the task of the carrier phase tracking circuit in the receiver. The transmitted data stream is segmented into eight bit blocks and quadrature amplitude modulated using a 256 point 4-D signal constellation whose 2-D constituent constellation is a 16 point square constellation doubly partitioned. The 4-D signal constellation is simply the Cartesian product of the 2-D signal constellation with it-self and has 32 subsets. The partition is performed on one side into four subsets A, B, C, and D with increased minimum-squared Euclidian distance, and on the other side into four rings, where each ring includes four points of equal energy. We propose both linear and nonlinear ST trellis codes and perform simulations using an appropriate multiple-input multiple-output (MIMO) channel model. The 4-D ST codes constructed here demonstrate about the same frame error rate (FER) performance as their 2-D counterparts, having however the added value of rotational invariance.

A Method of Statistical Randomness Test for Key Derivation Functions (키유도함수의 통계적 난수성 평가 방법)

  • Kang, Ju-Sung;Yi, Ok-Yeon;Youm, Ji-Sun;Cho, Jin-Woong
    • The KIPS Transactions:PartC
    • /
    • v.17C no.1
    • /
    • pp.47-60
    • /
    • 2010
  • Randomness is a basic security evaluation item for the most cryptographic algorithms. NIST has proposed a statistical test suit for random number generators for cryptographic applications in the process of AES project. However the test suit of NIST is customized to block ciphers which have the same input and output lengths. It needs to revise NIST's test suit for key derivation functions which have multiple output blocks. In this paper we propose a revised method of NIST's statistical randomness test adequate to the most key derivation functions and some experimental results for key derivation functions of 3GSM and NIST.

Delay Tolerant Information Dissemination via Coded Cooperative Data Exchange

  • Tajbakhsh, Shahriar Etemadi;Sadeghi, Parastoo
    • Journal of Communications and Networks
    • /
    • v.17 no.2
    • /
    • pp.133-144
    • /
    • 2015
  • In this paper, we introduce a system and a set of algorithms for disseminating popular content to a large group of wireless clients spread over a wide area. This area is partitioned into multiple cells and there is a base station in each cell which is able to broadcast to the clients within its radio coverage. Dissemination of information in the proposed system is hybrid in nature: Each base station broadcasts a fraction of information in the form of random linear combinations of data blocks. Then the clients cooperate by exchanging packets to obtain their desired messages while they are moving arbitrarily over the area. In this paper, fundamental trade-offs between the average information delivery completion time at the clients and different parameters of the system such as bandwidth usage by the base stations, average energy consumption by the clients and the popularity of the spread information are studied. Moreover different heuristic algorithms are proposed to control and maintain a balance over these trade-offs. Also, the more complicated case of multiple sessions where each client is interested in an arbitrary subset of sessions is considered and two variants of the basic dissemination algorithm are proposed. The performance of all the proposed algorithms is evaluated via extensive numerical experiments.