• Title/Summary/Keyword: Factor Graph

Search Result 167, Processing Time 0.025 seconds

Enhanced Belief Propagation Polar Decoder for Finite Lengths (유한한 길이에서 성능이 향상된 BP 극 복호기)

  • Iqbal, Shajeel;Choi, Goangseog
    • Journal of Korea Society of Digital Industry and Information Management
    • /
    • v.11 no.3
    • /
    • pp.45-51
    • /
    • 2015
  • In this paper, we discuss the belief propagation decoding algorithm for polar codes. The performance of Polar codes for shorter lengths is not satisfactory. Motivated by this, we propose a novel technique to improve its performance at short lengths. We showed that the probability of messages passed along the factor graph of polar codes, can be increased by multiplying the current message of nodes with their previous message. This is like a feedback path in which the present signal is updated by multiplying with its previous signal. Thus the experimental results show that performance of belief propagation polar decoder can be improved using this proposed technique. Simulation results in binary-input additive white Gaussian noise channel (BI-AWGNC) show that the proposed belief propagation polar decoder can provide significant gain of 2 dB over the original belief propagation polar decoder with code rate 0.5 and code length 128 at the bit error rate (BER) of $10^{-4}$.

A Low Power Hardware Allocation Algorithm for Design Automation (설계 자동화를 위한 저전력 하드웨어 할당 알고리듬)

  • 최지영;인치호
    • The Journal of Information Technology
    • /
    • v.3 no.1
    • /
    • pp.117-124
    • /
    • 2000
  • This paper proposes a new heuristic algorithm of a low power hardware allocation for Design Automation. The proposed algorithm works on scheduled input graph and allocates functional units, interconnections and registers by considering interdependency between operations and storage elements in each control step, in order to share registers and interconnections connected to functional units, as much as possible. The low power factor of the capacitance is reduced during the allocation. As the resource number reduce maximal . This paper shows the effectiveness of the algorithm by comparing experiments of existing system of the non low power.

  • PDF

Electron Spin Resonance Investigation of Fe3+ in Crystalline LiNbO3 Under the Polarized External Radiation

  • Park, Jung-Il;Cheong, Hai-Du
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.17 no.2
    • /
    • pp.92-97
    • /
    • 2013
  • We study the electron spin resonance line-width (ESRLW) of $Fe^{3+}$ in crystalline $LiNbO_3$ ; the ESRLW is obtained using the projection operator method (POM) developed by Argyres and Sigel. The ESRLW is calculated to be axially symmetric about the c-axis and is analyzed by the spin Hamiltonian with an isotopic g factor at a frequency of 9.5 GHz. The ESRLW increases exponentially as the temperature increases, and the ESRLW is almost constant in the high-temperature region (T>8000 K). This kind of temperature dependence of the ESRLW indicates a motional narrowing of the spectrum when $Fe^{3+}$ ions substitute the $Nb^{5+}$ ions in an off-center position. It is clear from this feature that there are two different regions in the graph of the temperature dependence of the ESRLW.

A Study on Improvement of Low-power Memory Architecture in IoT/edge Computing (IoT/에지 컴퓨팅에서 저전력 메모리 아키텍처의 개선 연구)

  • Cho, Doosan
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.24 no.1
    • /
    • pp.69-77
    • /
    • 2021
  • The widely used low-cost design methodology for IoT devices is very popular. In such a networked device, memory is composed of flash memory, SRAM, DRAM, etc., and because it processes a large amount of data, memory design is an important factor for system performance. Therefore, each device selects optimized design factors such as function, performance and cost according to market demand. The design of a memory architecture available for low-cost IoT devices is very limited with the configuration of SRAM, flash memory, and DRAM. In order to process as much data as possible in the same space, an architecture that supports parallel processing units is usually provided. Such parallel architecture is a design method that provides high performance at low cost. However, it needs precise software techniques for instruction and data mapping on the parallel architecture. This paper proposes an instruction/data mapping method to support optimized parallel processing performance. The proposed method optimizes system performance by actively using hardware and software parallelism.

A Method to Evaluate Distance Efficiency of Seoul Metropolitan Subway by Estimating Subway Detour Factor (지하철 우회계수 산정을 통한 수도권 지하철의 거리 효율 평가 모형)

  • LEE, Jae Min;KIM, Nam Seok
    • Journal of Korean Society of Transportation
    • /
    • v.33 no.3
    • /
    • pp.304-314
    • /
    • 2015
  • Detour of metro (subway) in metropolitan area has been regarded as one of inherent elements that make entire metro system less competitive than passenger cars. However, factors affecting detour of metro line is not specified clearly when a new subway system is planned or an existing system is improved. Previous detour-related studies was reviewed for developing 'distance efficeincy evaluation model' for metro as well as its counterpart (i.e. road). Metro line 3 (orange line) of Seoul metropolitan area was applied as a case study. As a results, the most detoured OD segment is Daechi - Apgujeong and its detour factor is 1.93 which means that the distance of the metro is 1.93 times longer distance compared to the distance of the road. The metro line 3 has averagely 20% longer distance compared to road for the identical O/D pairs.

Criticality effect according to axial burnup profiles in PWR burnup credit analysis

  • Kim, Kiyoung;Hong, Junhee
    • Nuclear Engineering and Technology
    • /
    • v.51 no.6
    • /
    • pp.1708-1714
    • /
    • 2019
  • The purpose of the critical evaluation of the spent fuel pool (SFP) is to verify that the maximum effective multiplication factor ($K_{eff}$) is less than the critical safety limit at 100% stored condition of the spent fuel with the maximum reactivity. At nuclear power plants, the storage standard of spent fuel, ie, the loading curve, is established to prevent criticality from being generated in SFP. Here, the loading curve refers to a graph showing the minimum discharged burnup versus the initial enrichment of spent fuel. Recently, US NRC proposed the new critical safety assessment guideline (DSS-ISG-2010-01, Revision 0) of PWR SFPs and most of utilities in US is following it. Of course, the licensed criterion of the maximum effective multiplication factor of SFP remains unchanged and it should be less than 0.95 from the 95% probability and the 95% confidence level. However, the new guideline is including the new evaluation methodologies like the application of the axial burnup profile, the validation of depletion and criticality code, and trend analysis. Among the new evaluation methodologies, the most important factor that affects $K_{eff}$ is the axial burnup profile of spent fuel. US NRC recommends to consider the axial burnup profiles presented in NUREG-6801 in criticality analysis. In this paper, criticality effect was evaluated considering three profiles, respectively: i) Axial burnup profiles presented in NUREG-6801. ii) Representative PWR axial burnup profile. iii) Uniform axial burnup profile. As the result, the case applying the axial burnup profiles presented in NUREG-6801 showed the highest $K_{eff}$ among three cases. Therefore, we need to introduce a new methodology because it can be issued if the axial burnup profiles presented in NUREG/CR-6801 are applied to the domestic nuclear power plants without any other consideration.

Studies on the Anodic Oxidation Behavior of Methanol and L-Ascorbic Acid by Using Glassy Carbon Electrodes Modified with Inorganic-Metal Polymeric Films (무기 금속 고분자 막을 도포시킨 유리질 탄소전극을 이용한 메탄올과 L-ascorbic acid의 양극 산화 거동에 관한 연구)

  • Yoo, Kwang-Sik;Woo, Sang-Beom
    • Analytical Science and Technology
    • /
    • v.11 no.5
    • /
    • pp.347-352
    • /
    • 1998
  • A study was carried out on the elelctrochemical characteristics of chemically modified electrodes (CMEs) by cyclic voltammetry. Fabrication of CMEs was made by coating with mixed valence (mv) inorganic-metal polymeric films on the glassy carbon electrode surface by potential cycling. Anodic oxidation behavior of methanol and L-ascorbic acid was studied by using CMEs working electrode. Deposition of films such as mv ruthenium oxo/ruthenium cyanide film (mv Ru-O/CN-Ru), mv ruthenium oxo/ferrocyanide film (mv Ru-O/$Fe(CN)_6$), and mv ruthenium oxo/ruthenium cyanide/Rhodium film (mv Ru-O/CN-Ru/Rh) was obtained to coat by scan rate of 50 mV/sec within the specified potential range (-0.5V ~ +1.2V). Film thickness was controlled by the repeat of the potential cycling. Anodic oxidation behavior of methanol was as follow. Calibration graph by using mv Ru-O/CN-Ru film showed linearly from 10 mM to 80 mM MeOH with slope factor of $-7.552{\mu}A/cm^2$. Although slope factor by using mv Ru-O/$Fe(CN)_6$ film was $-5.13{\mu}A/cm^2$, yet linear range of calibration graph could be extended from 10 mM to 100 mM MeOH. Anodic oxidation behavior of L-ascorbic acid was studied by mv Ru-O/CN-Ru film on the glassy carbon electrode and the glassy carbon electrode with Rh film, Glassy carbon electrode modified with Ru polymeric film was showed better sensitivity than the Rh-glassy carbon modified electrode (mv Ru-O/CN-Ru/Rh). Calibration graph was linear from 0.1 mM to 5 mM L-ascorbic acid by using glassy carbon electrode modified with Ru polymeric film. Solpe factor and relative coefficient are $-84.78{\mu}A/mM$ and 0.998, respectively.

  • PDF

Determination of Cr(Ⅵ) by Glassy Carbon and Platinum Electrodes Modified With Polypyrrole Film (폴리피롤 막으로 변성시킨 유리질 탄소 및 백금 전극에서 Cr(Ⅵ) 이온의 정량)

  • Yoo, Kwang Sik;Woo, Sang Beom;Jyoung, Jy Young
    • Journal of the Korean Chemical Society
    • /
    • v.43 no.4
    • /
    • pp.407-411
    • /
    • 1999
  • Studies have been carried out on the fabrication of PPy/GC and PPy/Pt electrode modified with polypyrrole film and determination of Cr(VI) by using 3-electrode system with modified electrodes. Modified electrodes were able to easily fabricated by cyclic voltammetry scanned from +1.0V to -1.0V(vs. Ag/AgCl) at 50 mV/sec. Film thickness could be controlled at same condition by the number of cycling up to 26 times. Reduction behaviour of Cr(VI) at PPy/GC electrode could be seen at wide potential ranges from +0.6V to -0.5V(vs. Ag/AgCl), and maximum reduction peak potential of the ion was observed at -0.25V(vs.Ag/AgCl). Calibration graph at its potential was linear from 0.1 ppm to 80.O ppm. Slope factor and relative coefficient were 1.75 mA/ppm and 0.998, respectively. Reduction behaviour of Cr(VI) at PPy/Pt electrode was similar to PPy/GC electrode, Calibration graph was linear from l.0 ppm to 60.0 ppm. Slope factor and relative coefficient were 0.5mA/ppm and 0.923, respectively. But PPy/GC modified electrode had about 3 times higher sensitivity than PPy/Pt modified electrode. Reduction behaviour of Cu(II), As(IlI), Pb(II), and Cd(II) couldn't be seen at PPy/GC electrode,Its metals had not lnterfered with Cr (VI) determination.

  • PDF

A Study on Skin Resistance Variability(SRV) over the Period of Ovarian Cycle of Women in their 20's and 30's with Normal and Regular Menstrual Cycles (정상월경주기를 가진 20-30대 여성의 난소주기에 따른 피부저항변이도 연구)

  • Ie, Jae-Eun;Cho, Hyun-Ju
    • The Journal of Korean Obstetrics and Gynecology
    • /
    • v.21 no.4
    • /
    • pp.183-193
    • /
    • 2008
  • Purpose: To research the changes of Skin Resistance Variability(SRV) over the period of ovarian cycle of healthy young women with normal and regular menstrual cycles using Oriental Medical Diagnose Autonomic system-3000 (OMD-3000). Methods: We measured SRV of 15 women who were working at O O Oriental Hospital from July to Oct. 2008. Each woman took the OMD-3000 test 8 times during 2 menstrual cycles. Each cycle consists of 4 phases-follicular phase, ovulation, luteal phase and menstruation. We analyse the data by SPSS 12.0 for windows. the one-way ANOVA by Repeated Measure(p<0.05). Results: 1. (1) The Factor AA means at zone 1 were 0.77$\pm$0.40, at zone 2 were 1.07$\pm$0.68, at zone 3 were 0.77$\pm$0.35, at zone 4 were 0.68$\pm$0.32, at zone 5 were 0.74$\pm$0.29, at zone 6 were 0.85$\pm$0.30, and at zone 7 were 0.74$\pm$0.29. The Factor AA means were lower than normal range at zone 1,3,4,5,6 and 7. The graph pattern of M shape was caused by the Factor AA means at zone 2 and zone 6 were higher than others. (2) The Factor AA means at zone 1 and zone 3 show abnormal regulation state. 2. During the menstruation. the Factor AA means were higher at zone 1,2 and 3 than other zones. During the ovulation, the Factor AA means were higher at zone 4,5,6 and 7 than other zones. Especially at the menstruation phase in zone 2 and at the ovulation phase in zone 6 tend to be highest means than other phases respectively. 3. However there were no significant difference of means during 4 ovarian phases in 7 zones except ovulation phase to luteal phase at zone 4(p = 0.013). Conclusion: The results suggest that changes of SRV during 4 menstrual cycles are not variables in reading 7-zone-diagnostic system. Further study will be needed.

  • PDF

The Development of Stretch Sensors for Measuring the Wrist Movements for People Using Fishing Lures (루어낚시 참여자의 손목 움직임 측정을 위한 스트레치 센서 개발)

  • Choi, Yoon-Seung;Park, Jin-hee;Kim, Joo-yong
    • Science of Emotion and Sensibility
    • /
    • v.25 no.3
    • /
    • pp.77-90
    • /
    • 2022
  • This study seeks to develop a stretch sensor for measuring the wrist movements of people using fishing lures. In order to confirm wrist movement, a stretch sensor was attached to the wrist band, and measurements of the dorsiflexion, plantar flexion, and fishing landing motion were measured using a scale to gauge factor, tensile strength, and elongation recovery rate. A conductive sensor using CNT dispersion was developed and applied to the E-band under the same conditions. A total of 15 sensors of the same size and five types of impregnation once, twice, and three times each were used to measure the gauge factor using UTM. The sensor that was impregnated twice had the best gauge rate, and the prototypes were manufactured with three sensors with high gauge rates and tensile strength. The results of the operation test conducted by connecting to the Arduino showed that Sample 1, which had the highest tensile strength and gauge factor, had a stable graph wavelength in three operations. Samples 2 and 3 showed stable wavelengths in the dorsiflexion and the plantar flexion; however, signal noise appeared in the fishing landing motion. This showed stable wavelengths in the two motions, but the wavelengths of the graphs differ depending on the tensile strength and gauge factor in the fishing landing motion. As a result, it was possible to identify the conditions necessary for manufacturing a stretch sensor for measuring wrist movement. This study will contribute to the development of smart wearable products for lure fishing.