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As software is getting more valuable, unauthorized users or malicious programmers illegally copies and distributes copyrighted software over online service provider (OSP) and P2P networks. To detect, block, and remove pirated software (illegal programs) on OSP and P2P networks, this paper proposes a new filtering approach using software birthmark, which is unique characteristics of program and can be used to identify each program. Software birthmark typically includes constant values, library information, sequence of function calls, and call graphs, etc. We target Microsoft Windows applications and utilize the numbers and names of DLLs and APIs stored in a Windows executable file. Using that information and each cryptographic hash value of the API sequence of programs, we construct software birthmark database. Whenever a program is uploaded or downloaded on OSP and P2P networks, we can identify the program by comparing software birthmark of the program with birthmarks in the database. It is possible to grasp to some extent whether software is an illegally copied one. The experiments show that the proposed software birthmark can effectively identify Windows applications. That is, our proposed technique can be employed to efficiently detect and block pirated programs on OSP and P2P networks. [ABSTRACT FROM AUTHOR]

The objective of this study is to design spacers using topology optimization in a two-dimensional (2D) crossflow reverse osmosis (RO) membrane channel in order to improve the performance of RO processes. This study is the first attempt to apply topology optimization to designing spacers in a RO membrane channel. The peiformance was evaluated based on the quantity of permeate flux penetrating both the upper and lower membrane sulfates. Here, Navier-Stokes and convection-diffusion equations were employed to calculate the permeate flux. The nine reference models, consisting of combinations of circle, rectangle, and triangle shapes and zig-zag, cavity, and submerged spacer configurations were then simulated using finite element method so that the peiformance of the model designed by topology optimization could be compared to the reference models. As a result of topology optimization with the allowable pressure drop changes in the channel, characteristics required of the spacer design were determined. The spacer design based on topology optimization was then simplified to consider manufacturability and peiformance. When the simplified design was compared to the reference models, the new design displayed a better peiformance in terms of permeate flux and wall concentration at the membrane surface. [ABSTRACT FROM AUTHOR]

Authenticated key exchange protocols are of fundamental importance in securing communications and are now extensively deployed for use in various real-world network applications. In this work, we reveal major previously unpublished security vulnerabilities in the password-based authenticated three-party key exchange protocol according to Lee and Hwang (2010): (1) the Lee-Hwang protocol is susceptible to a man-in-the-middle attack and thus fails to achieve implicit key authentication; (2) the protocol cannot protect clients' passwords against an offline dictionary attack; and (3) the indistinguishability-based security of the protocol can be easily broken even in the presence of a passive adversary. We also propose an improved password-based authenticated three-party key exchange protocol that addresses the security vulnerabilities identified in the Lee-Hwang protocol. [ABSTRACT FROM AUTHOR]

Drive-by-download attacks are client-side attacks that originate from web servers clients visit. High-interaction client honeypots identify malicious web pages by directly visiting the web pages and are very useful. However, they still have shortcomings that must be addressed: long inspection time and possibility of not detecting certain attacks such as time bombs. To address these problems, we propose a new detection method to identify web pages with time bombs. The proposed method introduces a pattern-based static analysis for detecting time bombs efficiently. A high-interaction client honeypot performs the static analysis before carrying out execution-based dynamic analysis. The static analysis classifies sample web pages into two groups, the first one assumed to be time-bombs and the second one assumed to be no time-bombs. We then perform dynamic analysis for the first using sequential visitation algorithm with long classification delay and for the second using divide-and-conquer visitation algorithm with short classification delay. Experimental results demonstrate that our method is more accurate and costs less than conventional methods. [ABSTRACT FROM AUTHOR]

Distributed operating systems are designed to run over a collection of computing nodes that are spatially disseminated and communicate through a computer network. The computing nodes interact collaboratively with each other in order to pursue a common purpose. Protecting group communication between the collaborating nodes against potential attacks is one of the major challenges faced by the designers of distributed operating systems. This challenge can be effectively addressed by a group key exchange (GKE) protocol which allows a group of communicating parties to build a secure multicast channel over an insecure network. In this work, we propose a scalable GKE protocol that achieves both constant round complexity and logarithmic computation complexity. Our GKE protocol achieves its scalability by employing a complete binary tree structure combined with a so-called "nonce-chained authentication technique". Besides the scalability, our protocol features provable security against active adversaries in a well-defined communication model. [ABSTRACT FROM AUTHOR]

Background: Among the Solanaceae plants, the pepper genome is three times larger than that of tomato. Although the gene repertoire and gene order of both species are well conserved, the cause of the genome-size difference is not known. To determine the causes for the expansion of pepper euchromatic regions, we compared the pepper genome to that of tomato. Results: For sequence-level analysis, we generated 35.6 Mb of pepper genomic sequences from euchromatin enriched 1,245 pepper BAC clones. The comparative analysis of orthologous gene-rich regions between both species revealed insertion of transposons exclusively in the pepper sequences, maintaining the gene order and content. The most common type of the transposon found was the LTR retrotransposon. Phylogenetic comparison of the LTR retrotransposons revealed that two groups of Ty3/Gypsy-like elements (Tat and Athila) were overly accumulated in the pepper genome. The FISH analysis of the pepper Tat elements showed a random distribution in heterochromatic and euchromatic regions, whereas the tomato Tat elements showed heterochromatinpreferential accumulation. Conclusions: Compared to tomato pepper euchromatin doubled its size by differential accumulation of a specific group of Ty3/Gypsy-like elements. Our results could provide an insight on the mechanism of genome evolution in the Solanaceae family. [ABSTRACT FROM AUTHOR]

Trichomes are present on nearly all land plants and protect plants against insect herbivores, drought and UV radiation. The trichome-bearing phenotype is conferred by the dominant allele of the pepper trichome locus 1 ( Ptl1) in Capsicum annuum, Mexican ‘Criollo de Morelos-334’ (CM334). A genetic analysis using simple sequence repeats from pepper cDNA identified the HpmsE031 marker as tightly linked to Ptl1 in 653 individuals of an F2 population derived from a cross between CM334 and Chilsungcho varieties. A bacterial artificial chromosome (BAC) library from CM334 covering 12× of the genome was screened using the HpmsE031 SSR marker as a probe and three BAC clones were identified. The Ptl1 region was covered by one 80 kb BAC clone, TT1B7. Fluorescence in situ hybridization (FISH) confirmed that TT1B7 localized to pepper chromosome 10. One co-dominant marker, Tco, and one dominant marker, Tsca, were successfully developed from the TT1B7 BAC sequence. Tco mapped 0.33 cM up from Ptl1 and Tsca mapped 0.75 cM down from Ptl1. Analysis of the BAC sequence predicts the presence of 14 open reading frames including 60S ribosomal protein L21-like protein ( Solanum demissum), protein kinase 2 ( Nicotiana tabacum), hypothetical proteins, and unnamed protein products. These results will provide not only useful information for map-based cloning of Ptl1 in Capsicum but also the starting points for analysis of R-gene cluster inked with Ptl1. [ABSTRACT FROM AUTHOR]

Recovery and salt rejection rate, which are directly related to the membrane properties and operating conditions (i.e., feed flow rate, pressure, temperature, and TDS concentration), are two main indicators for evaluating the performance of a reverse osmosis (RO) membrane process. A simple and rapid test with minimum data is inevitably requested to diagnose membrane performance at a certain operating conditions, because experiments at all operating conditions are inefficient and consumable work in the view of cost as well as man-hour. In this study, permeate flow rate and TDS concentration of three kinds of commercial RO membranes were carefully examined under various operating conditions [i.e., feed pressure (45-65 kgf/cm2) and temperature (5-30°C)]. Based on the experimental data, membrane resistance models including temperature and pressure correction factors were developed for the rapid diagnosis of SWRO membrane performances. As a result, the models developed in this study have good agreements between observed and simulated data. Based on the procedure in this study, the performance of any type of RO membranes can be rapidly examined by simple model parameter inputs. Furthermore, the developed diagnosis tool for performance test of SWRO membranes can be practically applied to build database of membrane performance for designing the SWRO process with minimum data as well as to reduce the cost and effort for data acquisition. [ABSTRACT FROM AUTHOR]

The Restorer-of-fertility ( Rf) gene is used for efficient hybrid seed production in chili pepper. Although molecular markers linked to Rf in pepper are available, their applications have been limited by lack of agreement between marker genotype and phenotype. To overcome this limitation, we developed new molecular markers using an Rf-segregating population for which most of previously developed markers are not suitable, because of lack of polymorphism. The petunia Rf gene was used as a candidate for marker development. First of all, a pepper bacterial artificial chromosome (BAC) library was screened using a pepper homolog of the petunia Rf gene. The 52 selected BAC clones were classified into three contig groups and each contig group was mapped to chromosome 6. Three markers were developed using the three groups; their genetic distances from the Rf locus were 1.4, 3.2 and 14 cM, respectively. In the second place, an Rf-linked marker was developed from the sequence of a tomoto BAC clone containing three genes which are homologous to petunia Rf gene. Genetic distance between this marker and Rf gene was 1.4 cM. When newly-, and previously-developed molecular markers linked to Rf were applied to 55 pepper breeding lines, one marker named CRF-SCAR was found to be the most broadly applicable, based on correct determination of phenotypes. In the present study, we demonstrate that previously cloned Rf genes can be used as candidate genes for development of new markers for the reliable detection of restorer lines. We expect that the newly-developed markers and information obtained from application of markers will be useful for reliable detection of restorer lines. [ABSTRACT FROM AUTHOR]

Parameters of earthquake sequences, for instance location and timing of foreshocks and aftershocks, are critical for understanding dynamics of mid-ocean ridge and transform faults. Whole sequences including small earthquakes in the ocean cannot be well recorded by land-based seismometers due to large epicentral distances. Recent hydroacoustic studies have demonstrated that T waves are very effective in detecting small submarine earthquakes because of little energy loss during propagation in Sound Fixing and Ranging channel. For example, an (2006 March 6, 40.11°S/78.49°E) transform-fault earthquake occurred at the Southeastern Indian Ocean Ridge, but National Earthquake Information Center only reported three aftershocks in the first following week. We applied cross-correlation method to hydroacoustic data from the International Monitoring System arrays in the Indian Ocean to examine the whole earthquake sequence. We detected 14 aftershocks and none foreshock for the earthquake and locations of these aftershocks show an irregular pattern. From the observation, we suggest that the feature could be caused by complicated transcurrent plate-boundary dynamics between two overlapped spreading ridges that is possibly explained by the bookshelf faulting model. [ABSTRACT FROM AUTHOR]

Phytophthora capsici Leonian, an oomycete pathogen, is a serious problem in pepper worldwide. Its resistance in pepper is controlled by quantitative trait loci (QTL). To detect QTL associated with P. capsici resistance, a molecular linkage map was constructed using 100 F2 individuals from a cross between Capsicum annuum ‘CM334’ and C. annuum ‘Chilsungcho’. This linkage map consisted of 202 restriction fragment length polymorphisms (RFLPs), 6 WRKYs and 1 simple sequence repeat (SSR) covering 1482.3 cM, with an average interval marker distance of 7.09 cM. QTL mapping of Phytophthora root rot and damping-off resistance was performed in F2:3 originated from a cross between resistant Mexican landrace C. annuum ‘CM334’ and susceptible Korean landrace C. annuum ‘Chilsungcho’ using composite interval mapping (CIM) analysis. Four QTL explained 66.3% of the total phenotypic variations for root rot resistance and three 44.9% for damping-off resistance. Of these QTL loci, two were located close to RFLP markers CDI25 on chromosome 5 (P5) and CT211A on P9. A bacterial artificial chromosome (BAC) library from C. annuum ‘CM334’ was screened with these two RFLP probes to obtain sequence information around the RFLP marker loci for development of PCR-based markers. CDI25 and CT211 probes identified seven and eight BAC clones, respectively. Nine positive BAC clones containing probe regions were sequenced and used for cytogenetic analysis. One single-nucleotide amplified polymorphism (SNAP) for the CDI25 locus, and two SSRs and cleaved amplified polymorphic sequence (CAPS) for CT211 were developed using sequences of the positive BAC clones. These markers will be valuable for rapid selection of genotypes and map-based cloning for resistance genes against P. capsici. [ABSTRACT FROM AUTHOR]

We investigate the effects of dielectric environments on the transition levels of Re and Nb dopants in monolayer MoS2 through density functional theory calculations. The inherently weakly screened Coulomb interaction in free-standing monolayer MoS2 makes the dopant electrons and holes strongly bound, and the Re and Nb impurities are found to produce deep levels. It is shown that when the monolayer MoS2 is placed near high permittivity dielectrics the screened Coulomb interaction induces carrier derealization with generating shallow levels. [ABSTRACT FROM AUTHOR]