• Title/Summary/Keyword: regular rules

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Efficient Regular Expression Matching Using FPGA (FPGA를 이용한 효율적 정규표현매칭)

  • Lee, Jang-Haeng;Lee, Seong-Won;Park, Neung-Soo
    • The KIPS Transactions:PartC
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    • v.16C no.5
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    • pp.583-588
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    • 2009
  • Network intrusion detection system (NIDS) monitors all incoming packets in the network and detects packets that are malicious to internal system. The NIDS should also have ability to update detection rules because new attack patterns are unpredictable. Incorporating FPGAs into the NIDS is one of the best solutions that can provide both high performance and high flexibility comparing with other approaches such as software solutions. In this paper we propose and design a novel approach, prefix sharing parallel pattern matcher, that can not only minimize additional resources but also maximize the processing performance. Experimental results showed that the throughput for 16-bit input is twice larger than for 8-bit input but the used LEs/Char in FPGA increases only 1.07 times.

A Study on the Driving Regulation of the Urban Railway Vehicles with Block Systems (폐색방식에 따른 도시철도차량운전 분류기준에 관한 연구 - 용어의 합리적인 개정을 중심으로 -)

  • Jeon, Y.S.;Lee, H.S.;Kim, C.S.
    • Journal of the Korean Society for Railway
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    • v.13 no.1
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    • pp.92-98
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    • 2010
  • Block system has been used to protect trains from occupying the same section of track at the same time so that only one train is permitted in each block at a time. Domestic driving regulations on the block system is divided into two classifications, such as regular block and substitute block. If it is impossible to use this regulation, the block applied method can be applied. However, domestic urban railway administrator has established his own operation rule within the regulation. Therefore, in order to assure continuous safety of train in operation, it is necessary to strengthen the regulation as can cope with the various block systems. In this study, domestic urban railway administration's own rules are examined and the appropriate driving regulation on the block system is proposed.

A Study on the Marine Accidents' Prevention of Korean Fishing Vessel which Foreign Seafarers are on board (외국인선원 승선 한국어선의 해양사고 예방에 관한 고찰)

  • Chong, Dae-Yul
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.1
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    • pp.57-63
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    • 2015
  • Foreign seafarers have embarked on the fishing vessels as industrial trainees since 1990s and the total number of foreign seafarers on merchant ships and fishing vessels marked 21,327 as of the end of 2013. Especially, in case of deep-sea fishing vessels and coastal/inshore fishing vessels, although the number of fishing vessels decreased, the number of foreign seafarers nearly doubled during recent 5 years. Looking at the marine accidents occurred to fishing vessels, after multinational seafarers are joining on board fishing vessels, difficulties in communication among seafarers has become a major issue. And the safety rules which could be understandable by foreign seafarers are not provided and the education and training for foreign seafarers are not properly conducted either. Consequently, the risk of marine accidents during fishing operation on fishing vessels has increased and emergency response under the captain's control was not effective enough to cope with such emergency situation. Several forced labour issues were also reported resulting from abusive words and assault committed by Korean seafarers. Therefore, This study aims first to review the cases of marine accidents on board fishing vessels which foreign seafarers are working and, the problems concerning employment and education for those foreign seafarers, and then to point out the necessity of conducting training on the safety rules and regular emergency drills for the foreign seafarers in order to prevent marine accidents.

Hybrid Behavior Evolution Model Using Rule and Link Descriptors (규칙 구성자와 연결 구성자를 이용한 혼합형 행동 진화 모델)

  • Park, Sa Joon
    • Journal of Intelligence and Information Systems
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    • v.12 no.3
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    • pp.67-82
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    • 2006
  • We propose the HBEM(Hybrid Behavior Evolution Model) composed of rule classification and evolutionary neural network using rule descriptor and link descriptor for evolutionary behavior of virtual robots. In our model, two levels of the knowledge of behaviors were represented. In the upper level, the representation was improved using rule and link descriptors together. And then in the lower level, behavior knowledge was represented in form of bit string and learned adapting their chromosomes by the genetic operators. A virtual robot was composed by the learned chromosome which had the best fitness. The composed virtual robot perceives the surrounding situations and they were classifying the pattern through rules and processing the result in neural network and behaving. To evaluate our proposed model, we developed HBES(Hybrid Behavior Evolution System) and adapted the problem of gathering food of the virtual robots. In the results of testing our system, the learning time was fewer than the evolution neural network of the condition which was same. And then, to evaluate the effect improving the fitness by the rules we respectively measured the fitness adapted or not about the chromosomes where the learning was completed. In the results of evaluating, if the rules were not adapted the fitness was lowered. It showed that our proposed model was better in the learning performance and more regular than the evolutionary neural network in the behavior evolution of the virtual robots.

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A Proposal for the Invigoration of Maritime Arbitration (해사중재 활성화를 위한 전제조건에 관한 논의)

  • Lee, Jung-Won
    • Journal of Arbitration Studies
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    • v.22 no.3
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    • pp.141-163
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    • 2012
  • In Korea, although nearly all maritime arbitration cases are dealt with by the Korean Commercial Arbitration Board (KCAB), the total number of cases that are referred to the KCAB is relatively small compared with the total number of maritime cases that occur in Korea. There may be reasons why maritime arbitration is not utilized more in Korea. However, of the above reasons, the superseding one may be that there is still a lack of confidence in the credibility and foreseeability of maritime arbitration in Korea. To expand the use of maritime arbitration in Korea, it is essential that the base surrounding maritime arbitration be expanded. In addition, it is also necessary that specialists receivetraining in maritime law. In this context, it is strongly recommended that maritime and admiralty law be taught in law schools and be included as a regular subject on the Korean bar exam. Additionally, to promote maritime arbitration, a rule should be introduced allowing for shortened arbitration proceedings in Korea. Although Chapter 8 of the KCAB Arbitration Rules provide for "Expedited Procedure," this process alone is not because the rules for Expedited Procedure generally apply in arbitration cases where both parties have agreed in a separate agreement to follow the procedures provided or in any domestic arbitration valued atless than 100,000,000 Korean won. Therefore, the KCAB Arbitration Rules for Expedited Procedure must be reformed to encompass international arbitrations. Additionally, experts who are experienced in the maritime sector should be elected as arbitrators. Given the factthat a fair number of arbitration cases can be characterized as international, it is important that businesspersons who are very fluent in English be appointed as arbitrators in order to increase the reliability of maritime arbitration in Korea and save costs. Meanwhile, because lawyers and scholars constitute a considerable portion of KCAB arbitrators, commercial persons from relevant industries should be enlisted as arbitrators. Even though there are arguments for the establishment of an independent maritime arbitration board in Korea, establishment of a separate maritime arbitration board will not directly guarantee the prosperity of maritime arbitration in Korea. Instead of instituting a new maritime arbitration board, it is better that a reorganized KCAB modify existing arbitration proceedings to make them faster and more economical if maritime arbitration is to prosper. In this regard, ad-hoc arbitration would be an option for speedy and thrifty maritime arbitration. Finally, to gain the confidence of domestic and foreign parties, we cannot ignore the importance of advertising the specialties and qualifications of the KCAB and its personnel among business entities.

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Hardware Approach to Fuzzy Inference―ASIC and RISC―

  • Watanabe, Hiroyuki
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.975-976
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    • 1993
  • This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}

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Multi-Beams modelling for high-rise buildings subjected to static horizontal loads

  • Sgambi, Luca
    • Structural Engineering and Mechanics
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    • v.75 no.3
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    • pp.283-294
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    • 2020
  • In general, the study of a high-rise building's behaviour when subjected to a horizontal load (wind or earthquake) is carried out through numerical modelling with finite elements method. This paper proposes a new, original approach based on the use of a multi-beams model. By redistributing bending and axial stiffness of horizontal elements (beams and slabs) along vertical elements, it becomes possible to produce a system of differential equations able to represent the structural behaviour of the whole building. In this paper this approach is applied to the study of bending behaviour in a 37-storey building (Torre Pontina, Latina, Italy) with a regular reinforced concrete structure. The load considered is the wind, estimated in accordance with Italian national technical rules and regulations. To simplify the explanation of the approach, the wind load was considered uniform on the height of building with a value equal to the average value of the wind load distribution. The system of differential equations' is assessed numerically, using Matlab, and compared with the obtainable solution from a finite elements model along with the obtainable solutions via classical Euler-Bernoulli beam theory. The comparison carried out demonstrates, in the case study examined, an excellent approximation of structural behaviour.

Low Luminosity AGNs at the center of the Perseus Cluster

  • Park, Songyoun;Yang, Jun;Oonk, Raymond;Paragi, Zsolt
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.44.1-44.1
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    • 2013
  • We investigate the origin of radio emission in nearby early-type galaxies using the European VLBI Network (EVN) at 1.4 GHz. The sample included NGC 1277, which was found to have an over-massive black hole of $1.7{\times}10^{10}M_{\odot}$, and four other early-type galaxies in the Perseus cluster. All the sources were detected above $5{\sigma}$. They show compact radio cores and high brightness temperatures, $10^7{\sim}10^9K$, which implies that radio emission in these objects is non-thermal. While the observed radio luminosities could be consistent with star formation (${\sim}1M_{\odot}yr^{-1}$), the small source size would imply a specific star formation rate (sSFR) of ${\sim}10^6M_{\odot}yr^{-1}kpc^{-2}$. Such a high sSFR rules out ongoing star formation. Supernovae (SNe) are ruled out as well because it is unlikely that we see SNe in all galaxies at the same time, and there is no significant radio variability either. The most plausible scenario is that these galaxies show low luminosity AGN activity in the radio, although there is no sign of AGN activity in other bands. If our interpretation is correct, then regular early-type galaxies may harbor active AGN more often than suspected from observations at other wavelengths.

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Preventive Measures of Battery Explosion in Lifeboat (구명정 배터리의 폭발사고 예방을 위한 대안)

  • Im, Myeong-Hwan;Ahn, Byong-Won
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.6
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    • pp.849-855
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    • 2011
  • Emergency batteries on board are used for stairs, pathway lights, and emergency communications during alternator black-out. In addition, there are engine start-up batteries in lifeboats. Typically, these batteries are installed under the Classification Rules. However, Since batteries inside life boats are installed in a confined narrow space, it is difficult to perform regular maintenances. Also, even though there are air vents in the life boat, the temperature inside the life boat often reaches above $65^{\circ}C$, which is much higher than the regulation temperature, $45^{\circ}C$. In this paper, we will summarize the accident of battery explosion occurred in MMU training ship, and possible causes. We will propose preventive measures of battery explosions as well as the revision of the regulation.

A Study on the Automated Process Planning System for Cold Forging of Non-axisymmetric Parts (비축대칭 제품의 냉간단조 공정설계시스템에 관한 연구)

  • Lee, Bong-Gyu;Jo, Hae-Yong;Gwon, Hyeok-Hong
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.2
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    • pp.195-202
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    • 2002
  • An automated process planning system for cold forging of non-axisymmetric parts of comparatively simple shape was developed in this study. Programs for the system have been written with Visual LISP in the AutoCAD using a personal computer and are composed of four main modules such as input module, shape cognition and shape expression module, material diameter determination module and process planning module. The design rules and knowledges for the system are extracted from the plasticity theories, handbook, relevant reference and empirical knowledge of field experts. Generally, in forging, only front view is needed for expression of axisymmetric parts, but non-axisymmetric parts need front and plane view. At the plane, this system cognizes the external shape of non-axisymmetric, parts - number of sides of regular polygon and radius of a circle circumscribing the polygon of n sides. At the front view, the system perceives diameter of axisymmetric portions and height of primitive geometries such as polygon, cylinder, cone, concave, convex, etc.