• Title/Summary/Keyword: population decoding

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Principles and Current Trends of Neural Decoding (뉴럴 디코딩의 원리와 최신 연구 동향 소개)

  • Kim, Kwangsoo;Ahn, Jungryul;Cha, Seongkwang;Koo, Kyo-in;Goo, Yong Sook
    • Journal of Biomedical Engineering Research
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    • v.38 no.6
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    • pp.342-351
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    • 2017
  • The neural decoding is a procedure that uses spike trains fired by neurons to estimate features of original stimulus. This is a fundamental step for understanding how neurons talk each other and, ultimately, how brains manage information. In this paper, the strategies of neural decoding are classified into three methodologies: rate decoding, temporal decoding, and population decoding, which are explained. Rate decoding is the firstly used and simplest decoding method in which the stimulus is reconstructed from the numbers of the spike at given time (e. g. spike rates). Since spike number is a discrete number, the spike rate itself is often not continuous and quantized, therefore if the stimulus is not static and simple, rate decoding may not provide good estimation for stimulus. Temporal decoding is the decoding method in which stimulus is reconstructed from the timing information when the spike fires. It can be useful even for rapidly changing stimulus, and our sensory system is believed to have temporal rather than rate decoding strategy. Since the use of large numbers of neurons is one of the operating principles of most nervous systems, population decoding has advantages such as reduction of uncertainty due to neuronal variability and the ability to represent a stimulus attributes simultaneously. Here, in this paper, three different decoding methods are introduced, how the information theory can be used in the neural decoding area is also given, and at the last machinelearning based algorithms for neural decoding are introduced.

Scalable Fingerprinting Scheme based on Angular Decoding for LCCA Resilience (선형결합 공모공격에 강인한 각도해석 기반의 대용량 핑거프린팅)

  • Seol, Jae-Min;Kim, Seong-Whan
    • The KIPS Transactions:PartD
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    • v.15D no.5
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    • pp.713-720
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    • 2008
  • Fingerprinting scheme uses digital watermarks to trace originator of unauthorized or pirated copies, however, multiple users may collude and escape identification by creating an average or median of their individually watermarked copies. Previous research works are based on ACC (anti-collusion code) for identifying each user, however, ACC are shown to be resilient to average and median attacks, but not to LCCA and cannot support large number of users. In this paper, we propose a practical SACC (scalable anti-collusion code) scheme and its angular decoding strategy to support a large number of users from basic ACC (anti-collusion code) with LCCA (linear combination collusion attack) robustness. To make a scalable ACC, we designed a scalable extension of ACC codebook using a Gaussian distributed random variable, and embedded the resulting fingerprint using human visual system based watermarking scheme. We experimented with standard test images for colluder identification performance, and our scheme shows good performance over average and median attacks. Our angular decoding strategy shows performance gain over previous decoding scheme on LCCA colluder set identification among large population.

Model Development for Lactic Acid Fermentation and Parameter Optimization Using Genetic Algorithm

  • LIN , JIAN-QIANG;LEE, SANG-MOK;KOO, YOON-MO
    • Journal of Microbiology and Biotechnology
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    • v.14 no.6
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    • pp.1163-1169
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    • 2004
  • An unstructured mathematical model is presented for lactic acid fermentation based on the energy balance. The proposed model reflects the energy metabolic state and then predicts the cell growth, lactic acid production, and glucose consumption rates by relating the above rates with the energy metabolic rate. Fermentation experiments were conducted under various initial lactic acid concentrations of 0, 30, 50, 70, and 90 g/l. Also, a genetic algorithm was used for further optimization of the model parameters and included the operations of coding, initialization, hybridization, mutation, decoding, fitness calculation, selection, and reproduction exerted on individuals (or chromosomes) in a population. The simulation results showed a good fit between the model prediction and the experimental data. The genetic algorithm proved to be useful for model parameter optimization, suggesting wider applications in the field of biological engineering.

An Integrated Planning of Production and Distribution in Supply Chain Management using a Multi-Level Symbiotic Evolutionary Algorithm (다계층 공생 진화알고리듬을 이용한 공급사슬경영의 생산과 분배의 통합계획)

  • 김여근;민유종
    • Journal of the Korean Operations Research and Management Science Society
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    • v.28 no.2
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    • pp.1-15
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    • 2003
  • This paper presents a new evolutionary algorithm to solve complex multi-level integration problems, which is called multi-level symbiotic evolutionary algorithm (MEA). The MEA uses an efficient feedback mechanism to flow evolution information between and within levels, to enhance parallel search capability, and to improve convergence speed and population diversity. To show the MEA's applicability, It is applied to the integrated planning of production and distribution in supply chain management. The encoding and decoding methods are devised for the integrated problem. A set of experiments has been carried out, and the results are reported. The superiority of the algorithm's performance is demonstrated through experiments.

Nutritional Biochemistry of Selenium (셀레늄의 영양생화학)

  • Choi, Yong-Soon;Hesketh, John E.
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.5
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    • pp.661-670
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    • 2006
  • Selenium (Se) obtained from dietary sources including cereals, grains and vegetables is an essential micronutrient for normal function of the body. Plants convert Se into selenomethionine and incorporate it into proteins in place of methionine, while higher animals synthesize selenoproteins containing selenocysteine. Excessive Se in the body is methylated stepwise to methylated selenium metabolites from selenide. Both inorganic and organic forms of selenium can be the nutritional sources in human, and they are transformed to selenide and then the amino acid selenocysteine attached to a specific $tRNA^{ser(sec)}$. The selenocysteine (Sec) is incorporated into selenoprotein sequences by the UGA codon. The decoding of UGA as Sec requires specific mechanisms because UGA is normally read as a stop codon: cis-acting sequences in the mRNA (the selenocysteine insertion sequence, SECIS, within the 3'untranslated region) and trans -acting factors dedicated to Sec incorporation are required for incorporation of Sec during translation of selenoprotein mRNAs. Approximately 25 selenoproteins have been identified in mammals. Several of these, including glutathione peroxidases, thioredoxin reductases and selenoprotein P, have been purified or cloned, allowing further characterization of their biological function. The antioxidant properties of selenoproteins help prevent cellular damage from free radicals which may contribute to the development of chronic disease such as cancer and heart disease. Other selenoproteins have important roles in regulation of thyroid function and play a role in the immune system. Daily selenium iatake was reported to be $42.0{\pm}16.9{\mu}g/day$ in Korean adult women. This review focuses on the metabolism and biological functions of selenium, and the nutritional status of selenium in the Korean population.

Latest Information Technologies in the UK Adults Education System

  • Tverezovska, Nina;Bilyk, Ruslana;Rozman, Iryna;Semerenko, Zhanna;Orlova, Nataliya;Vytrykhovska, Oksana;Oros, Ildiko
    • International Journal of Computer Science & Network Security
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    • v.22 no.8
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    • pp.25-34
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    • 2022
  • Today, further education of adults in the UK is one of the developing areas of continuing education. The Open University with distance learning, in the process of which innovative forms and methods based on computer and telecommunication technologies are used, is particularly successful in the organization of additional education of the adult population. The advantages of distance learning, multimedia - the latest information technologies, which provide the combination of graphic images, video, sound with the help of modern computer tools, are noted. The basic principles and forms underlying the technologies and forms of work with the elderly are defined. The international experience of implementing "Universities of the Third Age" is summarized. The most widespread approach in adult education in Great Britain is informational. The use of computer technologies motivates a new paradigm in educational methods and strategies, which requires new approaches, forms of learning, and innovative ways of delivering educational materials to adult learners. Information technologies have gained great popularity in such activities as distance learning, online learning, assistance in the education management system, development of programs and virtual textbooks in various subjects, online search for information for the educational process, computer testing of students' knowledge, creation of electronic libraries, formation of a single scientific electronic environment, publication of virtual magazines and newspapers on pedagogical topics, teleconferences, expansion of international cooperation in the field of Internet education. The information technology of synchronous distance learning "online" has gained considerable popularity in the educational process today. A promising direction is the use of multimedia technologies in educational activities to create a design of a virtual computer environment by decoding audiovisual information.