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A Study on Blind Nonlinear Channel Equalization using Modified Fuzzy C-Means (개선된 퍼지 클러스터 알고리즘을 이용한 블라인드 비선형 채널등화에 관한 연구)

  • Park, Sung-Dae;Han, Soo-Whan
    • Journal of Korea Multimedia Society
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    • v.10 no.10
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    • pp.1284-1294
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    • 2007
  • In this paper, a blind nonlinear channel equalization is implemented by using a Modified Fuzzy C-Means (MFCM) algorithm. The proposed MFCM searches the optimal channel output states of a nonlinear channel from the received symbols, based on the Bayesian likelihood fitness function instead of a conventional Euclidean distance measure. Next, the desired channel states of a nonlinear channel are constructed with the elements of estimated channel output states, and placed at the center of a Radial Basis Function (RBF) equalizer to reconstruct transmitted symbols. In the simulations, binary signals are generated at random with Gaussian noise. The performance of the proposed method is compared with that of a hybrid genetic algorithm (GA merged with simulated annealing (SA): GASA), and the relatively high accuracy and fast searching speed are achieved.

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Correlation Power Analysis Attack on Lightweight Block Cipher LEA and Countermeasures by Masking (경량 블록암호 LEA에 대한 상관관계 전력분석 공격 및 마스킹 대응 기법)

  • An, Hyo-Sik;Shin, Kyung-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.7
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    • pp.1276-1284
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    • 2017
  • Lightweight Encryption Algorithm (LEA) that was standardized as a lightweight block cipher was implemented with 8-bit data path, and the vulnerability of LEA encryption processor to correlation power analysis (CPA) attack was analyzed. The CPA used in this paper detects correct round keys by analyzing correlation coefficient between the Hamming distance of the computed data by applying hypothesized keys and the power dissipated in LEA crypto-processor. As a result of CPA attack, correct round keys were detected, which have maximum correlation coefficients of 0.6937, 0.5507, and this experimental result shows that block cipher LEA is vulnerable to power analysis attacks. A masking method based on TRNG was proposed as a countermeasure to CPA attack. By applying masking method that adds random values obtained from TRNG to the intermediate data of encryption, incorrect round keys having maximum correlation coefficients of 0.1293, 0.1190 were analyzed. It means that the proposed masking method is an effective countermeasure to CPA attack.

Antibiotic Resistance and Genetic Diversity of Listeria monocytogenes Isolated from Chicken Carcasses in Korea

  • Jang Sung-Sik;Choo Eui-Young;Han Ki-Seon;Miyamoto Takahisa;Heu Sung-Gi;Ryu Sang-Ryeol
    • Journal of Microbiology and Biotechnology
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    • v.16 no.8
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    • pp.1276-1284
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    • 2006
  • Listeria monocytogenes is a well-known high-risk foodborne pathogen that grows at refrigeration temperature and is responsible for outbreaks of listeriosis. We report here the incidence of L. monocytogenes in fresh chicken carcasses and present genetic diversity of L. monocytogenes isolates. In this study, 25 g of chicken carcasses from markets in Korea were examined according to the FDA method, and presumptive isolates were confirmed by multiplex PCR assay. L. monocytogenes isolates were analyzed by Pulsed-Field Gel Electrophoresis using restriction enzymes, ApaI and AscI, to obtain strain-specific DNA fragments profiles. Antimicrobial resistance of L. monocytogenes strains against generally used antibiotics (Penicillin G, Kanamycin, Tetracycline, Vancomycin, Cephalothin, Rifampicin, Erythromycin, Ampicillin, Gentamicin, Streptomycin, and Chloramphenicol) were analyzed by NCCLS protocols to examine the presence of antimicrobial resistance in natural L. monocytogenes. Of a total 274 chicken samples, 81 samples (29.6%) were positive for L. monocytogenes. Listeria innocua (50.1%), Listeria welshimeri (6.9%), and Listeria grayi (11.3%) were also detected. PFGE analysis, using restriction enzymes ApaI and AscI, showed 27 pulsotypes of L. monocytogenes. Antimicrobial resistance analysis confirmed the existence of antimicrobial resistance for penicillin G and tetracycline in isolated L. monocytogenes strains.

Bale Location Effects on Nutritive Value and Fermentation Characteristics of Annual Ryegrass Bale Stored in In-line Wrapping Silage

  • Han, K.J.;McCormick, M.E.;Derouen, S.M.;Blouin, D.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.9
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    • pp.1276-1284
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    • 2014
  • In southeastern regions of the US, herbage systems are primarily based on grazing or hay feeding with low nutritive value warm-season perennial grasses. Nutritious herbage such as annual ryegrass (Lolium multiflorum Lam.) may be more suitable for preserving as baleage for winter feeding even with more intensive production inputs. Emerging in-line wrapped baleage storage systems featuring rapid wrapping and low polyethylene film requirements need to be tested for consistency of storing nutritive value of a range of annual ryegrass herbage. A ryegrass storage trial was conducted with 24-h wilted 'Marshall' annual ryegrass harvested at booting, heading and anthesis stages using three replicated in-line wrapped tubes containing ten round bales per tube. After a six-month storage period, nutritive value changes and fermentation end products differed significantly by harvest stage but not by bale location. Although wilted annual ryegrass exhibited a restricted fermentation across harvest stages characterized by high pH and low fermentation end product concentrations, butyric acid concentrations were less than 1 g/kg dry matter, and lactic acid was the major organic acid in the bales. Mold coverage and bale aroma did not differ substantially with harvest stage or bale location. Booting and heading stage-harvested ryegrass baleage were superior in nutritive value to anthesis stage-harvested herbage. Based on the investigated nutritive value and fermentation characteristics, individual bale location within in-line tubes did not significantly affect preservation quality of ryegrass round bale silages.

An Analysis of the Vulnerability of SSL/TLS for Secure Web Services (안전한 웹 서비스를 위한 SSL/TLS 프로토콜 취약성 분석)

  • 조한진;이재광
    • Journal of the Korea Computer Industry Society
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    • v.2 no.10
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    • pp.1269-1284
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    • 2001
  • The Secure Sockets Layer is a protocol for encryption TCP/IP traffic that provides confidentiality, authentication and data integrity. Also the SSL is intended to provide the widely applicable connection-oriented mechanism which is applicable for various application-layer, for Internet client/server communication security. SSL, designed by Netscape is supported by all clients' browsers and server supporting security services. Now the version of SSL is 3.0. The first official TLS vl.0 specification was released by IETF Transport Layer Security working group in January 1999. As the version of SSL has had upgraded, a lot of vulnerabilities were revealed. SSL and TLS generate the private key with parameters exchange method in handshake protocol, a lot of attacks may be caused on this exchange mechanism, also the same thing may be come about in record protocol. In this paper, we analyze SSL protocol, compare the difference between TLS and SSL protocol, and suggest what developers should pay attention to implementation.

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Bioconversion of Sugarcane Bagasse with Japanese Koji by Solid-state Fermentation and Its Effects on Nutritive Value and Preference in Goats

  • Ramli, M.N.;Imura, Y.;Takayama, K.;Nakanishi, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.9
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    • pp.1279-1284
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    • 2005
  • The effects of 3 different strains of Japanese koji (Aspergillus oryzae, A. sojae and A. awamori) in the solid-state fermentation (SSF) of sugarcane bagasse mixed with wheat bran on chemical composition, energy, in vivo digestibility and preference of the fermented bagasse feeds (FBF) in goats were investigated. Diets consisted of lucerne hay cube (basal diet) and unfermented bagasse feed (control), FBF with A. oryzae (O), FBF with A. sojae (S) or FBF with A. awamori (A), which were mixed in a total ration of 7:3 (w/w DM). Three Nubian does were fed each of the diets, i.e. control, O, S and A in the 4 consecutive periods for digestion trials (21-day each). The goats were also used for preference trials (30-min each) of O, S and A. The O was significantly higher in CP content than others (p<0.05). The crude fiber (CF), ADF and cellulose contents of control were significantly lower than those of other diets (p<0.05). The S had significantly higher CF digestibility than control (p<0.05), and it revealed the largest value of all. Digestibilities of NDF, ADF and cellulose in S were significantly higher than those of control (about 10, 18 and 18%, respectively, p<0.05). The DE of S was significantly higher than that of others (p<0.05), though there were no significant differences in DCP and TDN between control and S. The results of preference trials demonstrated that the average intake rate was not significantly different among diets, but O and S are likely to be preferable to A (p<0.1). It was concluded that the SSF of bagasse feeds by Japanese koji can improve the fiber digestion, especially NDF, ADF or cellulose in goats, and there is a marked effect in the feed containing A. sojae, which may lead to the improvement of DE.

Effect of Plant Fibre on the Solubility of Mineral Elements

  • Ibrahim, M.N.M.;Zemmelink, G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.8
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    • pp.1277-1284
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    • 1999
  • Eight feeds and their residues left after washing with tap water (water residue) or incubation in the rumen (rumen residues) were treated with hydrochloric acid, neutral detergent solution without EDTA (NDS) or both, and the release or sorption of minerals (Ca, Mg, P, Na, K, Cu and Zn) assessed. Six of the feeds were from Sri Lanka (Panicum maximum ecotype Guinea A, Glyricidia maculate, Artocarpus heterophyllus (jak leaves), untreated and urea-treated rice straw, and rice bran) and two from the Netherlands (maize silage and wheat straw). The initial concentration of mineral elements, the concentration of neutral detergent fibre (NDF) and the type of feed significantly influenced (p<0.01). The proportion of the mineral elements released or sorbed. In general, feeds with high NDF content (straws and guinea grass) sorbed Ca from tap water, or released less in the rumen, and within these feeds the extent of sorption varied with source of fibre. Acid or NDS treatment removed little of the sorbed Ca, but they removed much of the Mg from both water and rumen residues. Fibres of wheat straw and jak leaves showed an affinity for Mg in the rumen. All feeds and their water and rumen residues sorbed P and Na from NDS, and the extent of sorption varied with the initial concentrations of these elements and with the type of fibre. Acid treatment removed part of the sorbed Na, but not the P. The solubility of K was not affected by the content of NDF, the type of fibre or the initial concentration of K. All feeds and their residues, except for the rumen residues of rice bran sorbed Cu from tap water and in the rumen. The recovery of Cu in rumen residues declined from 353% to 147% after NDS treatment, and with some feeds (glyricidia and jak leaves) the recovery was below 100%. Acid treatment removed part of the Zn sorbed by the water and rumen residues, but the capacity of residues to retain Zn varied with the type of feed.

Biodiesel Production: Utilization of Loofah Sponge to Immobilize Rhizopus chinensis CGMCC #3.0232 Cells as a Whole-Cell Biocatalyst

  • He, Qiyang;Xia, Qianjun;Wang, Yuejiao;Li, Xun;Zhang, Yu;Hu, Bo;Wang, Fei
    • Journal of Microbiology and Biotechnology
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    • v.26 no.7
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    • pp.1278-1284
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    • 2016
  • Rhizopus chinensis cells immobilized on loofah (Luffa cylindrica) sponges were used to produce biodiesel via the transesterification of soybean oil. In whole-cell immobilization, loofah sponge is considered to be a superior alternative to conventional biomass carriers because of its biodegradable and renewable properties. During cell cultivation, Rhizopus chinensis mycelia can spontaneously and firmly adhere to the surface of loofah sponge particles. The optimal conditions for processing 9.65 g soybean oil at 40℃ and 180 rpm using a 3:1 methanol-to-oil molar ratio were found to be 8% cell addition and 3-10% water content (depending on the oil's weight). Under optimal conditions, an over 90% methyl ester yield was achieved after the first reaction batch. The operational stability of immobilized Rhizopus chinensis cells was assayed utilizing a 1:1 methanol-to-oil molar ratio, thus resulting in a 16.5-fold increase in half-life when compared with immobilized cells of the widely studied Rhizopus oryzae. These results suggest that transesterification of vegetable oil using Rhizopus chinensis whole cells immobilized onto loofah sponge is an effective approach for biodiesel production.

Classification of Client-side Application-level HTTP Traffic (HTTP 트래픽의 클라이언트측 어플리케이션별 분류)

  • Choi, Mi-Jung;Jin, Chang-Gyu;Kim, Myung-Sup
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.11B
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    • pp.1277-1284
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    • 2011
  • Today, many applications use 80 port, which is a basic port number of HTTP protocol, to avoid a blocking of firewall. HTTP protocol is used in not only Web browsing but also many applications such as the search of P2P programs, update of softwares and advertisement transfer of nateon messenger. As HTTP traffics are increasing and various applications transfer data through HTTP protocol, it is essential to identify which applications use HTTP and how they use the HTTP protocol. In order to prevent a specific application in the firewall, not the protocol-level, but the application-level traffic classification is necessary. This paper presents a method to classify HTTP traffics based on applications of the client-side and group the applications based on providing services. We developed an application-level HTTP traffic classification system and verified the method by applying the system to a small part of the campus network.

Detection of Subcarrier-Multiplexed Optical Label Using Optical interleave (광 인터리버를 이용한 부반송파 다중화된 광 레이블 검출)

  • Shin Jong Dug;Lee Moon Hwan;Kim Boo Gyoun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.12A
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    • pp.1279-1284
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    • 2004
  • In this paper, we propose a novel and simple optical technique for the detection of subcarrier-multiplexed(SCM) labels using optical interleavers. Optical-baseband packet signals with suppressed subcarriers appear at the through-pass port of the optical interleaver and SCM labels with suppressed optical carrier exit from the optical SCM extraction port. Since it does not require optical circulators, this structure shows less insertion loss than the previously proposed optical label detectors. The periodic nature of the interleaver transfer function makes it possible to detect multiple SCM channels simultaneously from an incoming wavelength-multiplexed signal stream. Detection of a 155-Mb/s ASK modulated 9.79-GHz subcarrier using a 10-GHz SCM optical label detector has been performed successfully and verified through optical spectra and bi t-error-rate measurements.