• Title/Summary/Keyword: 76회

Search Result 1,578, Processing Time 0.026 seconds

Improvement of Flexible Zerotree Coder by Efficient Transmission of Wavelet Coefficients (웨이블렛 계수의 효율적인 전송에 따른 가변제로트리코더의 성능개선)

  • Joo, Sang-Hyun;Shin, Jae-Ho
    • Journal of the Korean Institute of Telematics and Electronics C
    • /
    • v.36C no.9
    • /
    • pp.76-84
    • /
    • 1999
  • EZW proposed by Shapiro is based on a zerotree constructed in a way that a parent coefficient in a subband is related to four child coefficients in the next finer subband of similar orientation. This fixed treeing based on 1-to-4 parent-child is suitable to exploti hierachical correlations among subbands but not to exploit spatial correlations within a subband. A new treeing by Joo, et al. is suggested to simulatneously exploit those two correlatins by extending parent-child relationship in a flexible way. The flexible treeing leads to increasing the number of symbols and lowering entorpy comparing to the fixed treeing, and therefore a better compression can be resulted. In this paper, we suggest two techniques to suppress the increasing of symbols. First, a probing bit is generated to avoid redundant scan for insignivicant coefficients. Second, since all subbands do not always require the same kind of symbol-set, produced symbols are re-symbolized into binary codes according to a pre-defined procedure. Owing to those techniques, all symbols are generated as binary codes. The binary symbols can be entropy-coded by an adaptive arithmetic coding. Moerover, the binary symbol stream can give comparatively good performances without help of additional entropy coding. Our proposed coding scheme is suggested in two modes: binary coding mode and arithmetic coding mode. We evaluate the effectivenessof our modifications by comparing with the original EZW.

  • PDF

A 12b 1kS/s 65uA 0.35um CMOS Algorithmic ADC for Sensor Interface in Ubiquitous Environments (유비쿼터스 환경에서의 센서 인터페이스를 위한 12비트 1kS/s 65uA 0.35um CMOS 알고리즈믹 A/D 변환기)

  • Lee, Myung-Hwan;Kim, Yong-Woo;Lee, Seung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.45 no.3
    • /
    • pp.69-76
    • /
    • 2008
  • This work proposes a 12b 1kS/s 65uA 0.35um CMOS algorithmic ADC for sensor interface applications such as accelerometers and gyro sensors requiring high resolution, ultra-low power, and small size simultaneously. The proposed ADC is based on an algorithmic architecture with recycling techniques to optimize sampling rate, resolution, chip area, and power consumption. Two versions of ADCs are fabricated with a conventional open-loop sampling scheme and a closed-loop sampling scheme to investigate the effects of offset and 1/f noise during dynamic operation. Switched bias power-reduction techniques and bias circuit sharing reduce the power consumption of amplifiers in the SHA and MDAC. The current and voltage references are implemented on chip with optional of-chip voltage references for low-power SoC applications. The prototype ADC in a 0.35um 2P4M CMOS technology demonstrates a measured DNL and INL within 0.78LSB and 2.24LSB, and shows a maximum SNDR and SFDR of 60dB and 70dB in versionl, and 63dB and 75dB in version2 at 1kS/s. The versionl and version2 ADCs with an active die area of $0.78mm^2$ and $0.81mm^2$ consume 0.163mW and 0.176mW at 1kS/s and 2.5V, respectively.

The Scientific Analysis of Aged' Shoe for Health Promotion (노인 건강증진용 신발의 운동과학적 효과분석)

  • Jin, Young-Wan;Kwak, Yi-Sub
    • Journal of Life Science
    • /
    • v.21 no.9
    • /
    • pp.1336-1345
    • /
    • 2011
  • The purpose of this study was to analyze and compare the effects of exercise science of shoes for Aged' health promotion. Kinematic and kinetic data were collected using cinematography and the Zebris system (Zebris Emed Sensor Platform, GR-DVL9800) to analyze pressure of foot and ground reaction force. Subjects recruited were 20 healthy elderly men. They walked at 1.36m/sec velocity wearing type A (domestic), type B (foreign) and walking shoes (A company). One-way ANOVA was used to analyze statistics. The results were as following: no significant differences were observed in gait variables among the three groups (p<0.05). There was a significant difference in max pronation angle of heels examined among the three groups (p<0.05). There were no significant differences in kinetic variables (ground reaction force and max pressure) among the three groups (p<0.05). A physiology study was performed to analyze the effects of walking with shoes with silver added to them on percent body fat, resting metabolic rate and energy expenditure. Sixty adults males were recruited from the public health center. They were divided into four groups. C: control group (n=20), EY: elderly Y group (n=20), and EO: elderly O group (n=20). The results of this study were as follows: percent body fat was decreased following each exercise period, however, not all the groups showed a significant difference. The change of resting metabolic rate was significantly increased in HI (high intensity) and LI (low intensity) periods in the C and EY groups. However, there was no significant difference in the EO group. The mean energy expenditure during and after exercise were significantly lowered in all periods compared to the control group.

An Efficient Dynamic Network Status Update Mechanism for QoS Routing (QoS 라우팅을 위한 효율적인 동적 네트워크 상태 정보 갱신 방안)

  • Kim, Jee-Hye;Lee, Mee-Jeong
    • Journal of KIISE:Information Networking
    • /
    • v.29 no.1
    • /
    • pp.65-76
    • /
    • 2002
  • QoS routing is a routing technique for finding feasible path that satisfies QoS requirements required by application programs. Since QoS routing determines such paths in terms of dynamic network state, it satisfies the requirement of applications and increases the utilization of the network. The overhead is, however, generated by routers to exchange the information of the dynamic state of network. In order to reduce this protocol overhead, a timer based update mechanism is proposed in which router checks the change of the network status periodically and network state information is exchanged if the change is greater than a certain value. Using large update period makes, though, routing performance irresponsive to the parameters which determine the update of the network state of the router. In addition to this, large update period may result in inaccurate network state information at routers and cause resource reservation failure. The resource reservation failure generates additional overhead to cancel the resource reservation of the part of the path. In this paper, we propose mechanisms enhancing the existing network state update policy with respect to these two problems. Performance of the proposed schemes are evaluated through a course of simulation.

Ticks Collected from Selected Mammalian Hosts Surveyed in the Republic of Korea During 2008-2009

  • Kim, Heung-Chul;Han, Sang-Hoon;Chong, Sung-Tae;Klein, Terry A.;Choi, Chang-Yong;Nam, Hyun-Young;Chae, Hee-Young;Lee, Hang;Ko, Sung-Jin;Kang, Jun-Gu;Chae, Joon-Seok
    • Parasites, Hosts and Diseases
    • /
    • v.49 no.3
    • /
    • pp.331-335
    • /
    • 2011
  • A tick survey was conducted to determine the relative abundance and distribution of ticks associated with selected mammals in the Republic of Korea (ROK) during 2008-2009. A total of 918 ticks were collected from 76 mammals (6 families, 9 species) captured at 6 provinces and 3 Metropolitan Cities in ROK. Haemaphysalis longicornis (54.4%) was the most frequently collected tick, followed by Haemaphysalis flava (28.5%), Ixodes nipponensis (7.6%), Ixodes pomerantzevi (4.8%), Ixodes persulcatus (4.6%), and Haemaphysalis japonica (0.1%). Adults (57.0%) and nymphs (28.7%) of Ixodes and Haemaphysalis spp. were collected most frequently from medium or large mammals in this survey, while few larvae (14.3%) were collected. Hydropotes inermis was the most frequently captured mammal (52.6%), with a 16.4 tick index and 5 of 6 species of ticks collected during this survey. H. longicornis (69.7%) was the predominant tick collected from H. inermis, followed by H. flava (22.2%), I. persulcatus (6.1%), I. nipponensis (1.8%), and H. japonica (0.2%).

A Cluster-based Power-Efficient Routing Protocol for Sensor Networks (센서 네트워크를 위한 클러스터 기반의 에너지 효율적인 라우팅 프로토콜)

  • Kweon, Ki-Suk;Lee, Seung-Hak;Yun, Hyun-Soo
    • Journal of KIISE:Information Networking
    • /
    • v.33 no.1
    • /
    • pp.76-90
    • /
    • 2006
  • Sensor network consists of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it. The life time of each node in the sensor network significantly affects the life time of whole sensor network. A node which drained out its battery may incur the partition of whole network in some network topology The life time of each node depends on the battery capacity of each node. Therefore if all sensor nodes in the network live evenly long, the life time of the network will be longer. In this paper, we propose Cluster-Based Power-Efficient Routing (CBPER) Protocol which provides scalable and efficient data delivery to multiple mobile sinks. Previous r(luting protocols, such as Directed Diffusion and TTDD, need to flood many control packets to support multiple mobile sinks and many sources, causing nodes to consume their battery. In CBPER, we use the fact that sensor nodes are stationary and location-aware to construct and maintain the permanent grid structure, which makes nodes live longer by reducing the number of the flooding control packets. We have evaluated CBPER performance with TTDD. Our results show that CBPER is more power-efficient routing protocol than TTDD.

Counter Measures by using Execution Plan Analysis against SQL Injection Attacks (실행계획 분석을 이용한 SQL Injection 공격 대응방안)

  • Ha, Man-Seok;Namgung, Jung-Il;Park, Soo-Hyun
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.53 no.2
    • /
    • pp.76-86
    • /
    • 2016
  • SQL Injection attacks are the most widely used and also they are considered one of the oldest traditional hacking techniques. SQL Injection attacks are getting quite complicated and they perform a high portion among web hacking. The big data environments in the future will be widely used resulting in many devices and sensors will be connected to the internet and the amount of data that flows among devices will be highly increased. The scale of damage caused by SQL Injection attacks would be even greater in the future. Besides, creating security solutions against SQL Injection attacks are high costs and time-consuming. In order to prevent SQL Injection attacks, we have to operate quickly and accurately according to this data analysis techniques. We utilized data analytics and machine learning techniques to defend against SQL Injection attacks and analyzed the execution plan of the SQL command input if there are abnormal patterns through checking the web log files. Herein, we propose a way to distinguish between normal and abnormal SQL commands. We have analyzed the value entered by the user in real time using the automated SQL Injection attacks tools. We have proved that it is possible to ensure an effective defense through analyzing the execution plan of the SQL command.

Common Services Platform for M2M Supporting Security Standards (보안 표준 지원 M2M 공통 서비스 플랫폼)

  • Vakkosov, Sardorjon;Namgung, Jung-Il;Park, Soo-Hyun
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.53 no.3
    • /
    • pp.76-88
    • /
    • 2016
  • Machine to Machine (M2M) is a technology that presents communication between two or more devices with or without human intervention. M2M communications can be applied for various use cases such as environmental monitoring, health care, smart metering and etc. In most use cases, M2M utilizes sensor nodes to collect data from the intended environment and the data is transmitted back to M2M application through other devices (gateways, sink nodes). In some use cases, M2M devices are being designed to store and process sensor data for improving the reliability of the service; Gateways and sink nodes are also intended to store and process the gathered data from sensor nodes. This kind of approach is very challenging for both academy and industry. In order to enhance the performance of this approach, in this paper, we propose our Common Service Security Platform (CSSP) for M2M devices and gateways. CSSP platform presents solutions for the devices and gateways by making them operate more accurately and efficiently. Besides, we present a comparative analysis of communication protocols and present their performance in accordance with selected metrics.

The Motion Estimator Implementation with Efficient Structure for Full Search Algorithm of Variable Block Size (다양한 블록 크기의 전역 탐색 알고리즘을 위한 효율적인 구조를 갖는 움직임 추정기 설계)

  • Hwang, Jong-Hee;Choe, Yoon-Sik
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.46 no.11
    • /
    • pp.66-76
    • /
    • 2009
  • The motion estimation in video encoding system occupies the biggest part. So, we require the motion estimator with efficient structure for real-time operation. And for motion estimator's implementation, it is desired to design hardware module of an exclusive use that perform the encoding process at high speed. This paper proposes motion estimation detection block(MED), 41 SADs(Sum of Absolute Difference) calculation block, minimum SAD calculation and motion vector generation block based on parallel processing. The parallel processing can reduce effectively the amount of the operation. The minimum SAD calculation and MED block uses the pre-computation technique for reducing switching activity of the input signal. It results in high-speed operation. The MED and 41 SADs calculation blocks are composed of adder tree which causes the problem of critical path. So, the structure of adder tree has changed the most commonly used ripple carry adder(RCA) with carry skip adder(CSA). It enables adder tree to operate at high speed. In addition, as we enabled to easily control key variables such as control signal of search range from the outside, the efficiency of hardware structure increased. Simulation and FPGA verification results show that the delay of MED block generating the critical path at the motion estimator is reduced about 19.89% than the conventional strukcture.

Analysis of the Influence of Holding Pharmacist Specialization for Professionalism and Job Satisfaction (전문약사 자격 보유여부에 따른 전문성 및 직무만족도 영향 분석)

  • Jung, Sun Hoi;Choi, Kyung Hee;Kwon, Kyeng Hee;Rhew, Kiyon
    • Journal of Korean Society of Health-System Pharmacists
    • /
    • v.35 no.4
    • /
    • pp.441-452
    • /
    • 2018
  • Background : The prevalence of the chronic metabolic disease is increasing due to the aging society. Therefore, Korean Society of Health-system Pharmacists (KSHP) has a specialty pharmacist system to improve the professionalism of pharmacists. The purpose of this study is to suggest the difference between specialty pharmacist and non-specialty pharmacist with regards to their knowledge, delivery of information on medication, service provision, and job satisfaction. Methods : An online survey research was conducted for hospital pharmacists. The reliability of the questionnaire items was presented using Cronbach's ${\alpha}$ test. The t-test or ANOVA analysis was used for evaluating differences in continuous variables. Results : A total of 171 pharmacists responded to the questionnaire, and 87.7% of the respondents were aged less than 30 years (76.6%) and four-year graduates (86.0%). Typically, 108 (63.2%) were candidates for the pharmacist's specialty certificate, and the remaining 63 (36.8%) were not enrolled. Considering the field of specialty with overlapping, the total number of certificated patients was 140 (26.3% of the total of 532 in 2016). The results of the reliability analysis of the specific questionnaire showed that the Cronbach's ${\alpha}$ value was over 0.78. There was no significant difference in customer directionality between the two groups. However, there was a significant difference (p<0.05) with respect to overall knowledge about the treatment process, drug efficacy, and side effects, information about medicines and adverse drug reactions, and in providing appropriate information to medical staff including patients and physicians. Conclusions : The pharmacist with specialization showed a positive result of self-evaluation of items such as knowledge about drugs, communication of information on medications, and service provision, compared to other pharmacists, and the result was in correlation with the numbers of specialization. There was no difference in job satisfaction related to working environment. Henceforth, it is hypothesized that there is a necessity for continuous improvement in the working environment to suit the purpose of the pharmacy specialist system.