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Weina NIU Xiaosong ZHANG Guowu YANG Ruidong CHEN Dong WANG
Advanced Persistent Threat (APT) is one of the most serious network attacks that occurred in cyberspace due to sophisticated techniques and deep concealment. Modeling APT attack process can facilitate APT analysis, detection, and prediction. However, current techniques focus on modeling known attacks, which neither reflect APT attack dynamically nor take human factors into considerations. In order to overcome this limitation, we propose a Targeted Complex Attack Network (TCAN) model for APT attack process based on dynamic attack graph and network evolution. Compared with current models, our model addresses human factors by conducting a two-layer network structure. Meanwhile, we present a stochastic model based on states change in the target network to specify nodes involved in the procedure of this APT. Besides, our model adopts time domain to expand the traditional attack graph into dynamic attack network. Our model is featured by flexibility, which is proven through changing the related parameters. In addition, we propose dynamic evolution rules based on complex network theory and characteristics of the actual attack scenarios. Finally, we elaborate a procedure to add nodes by a matrix operation. The simulation results show that our model can model the process of attack effectively.
Andrew FINCH Keiji YASUDA Hideo OKUMA Eiichiro SUMITA Satoshi NAKAMURA
The contribution of this paper is two-fold. Firstly, we conduct a large-scale real-world evaluation of the effectiveness of integrating an automatic transliteration system with a machine translation system. A human evaluation is usually preferable to an automatic evaluation, and in the case of this evaluation especially so, since the common machine translation evaluation methods are affected by the length of the translations they are evaluating, often being biassed towards translations in terms of their length rather than the information they convey. We evaluate our transliteration system on data collected in field experiments conducted all over Japan. Our results conclusively show that using a transliteration system can improve machine translation quality when translating unknown words. Our second contribution is to propose a novel Bayesian model for unsupervised bilingual character sequence segmentation of corpora for transliteration. The system is based on a Dirichlet process model trained using Bayesian inference through blocked Gibbs sampling implemented using an efficient forward filtering/backward sampling dynamic programming algorithm. The Bayesian approach is able to overcome the overfitting problem inherent in maximum likelihood training. We demonstrate the effectiveness of our Bayesian segmentation by using it to build a translation model for a phrase-based statistical machine translation (SMT) system trained to perform transliteration by monotonic transduction from character sequence to character sequence. The Bayesian segmentation was used to construct a phrase-table and we compared the quality of this phrase-table to one generated in the usual manner by the state-of-the-art GIZA++ word alignment process used in combination with phrase extraction heuristics from the MOSES statistical machine translation system, by using both to perform transliteration generation within an identical framework. In our experiments on English-Japanese data from the NEWS2010 transliteration generation shared task, we used our technique to bilingually co-segment the training corpus. We then derived a phrase-table from the segmentation from the sample at the final iteration of the training procedure, and the resulting phrase-table was used to directly substitute for the phrase-table extracted by using GIZA++/MOSES. The phrase-table resulting from our Bayesian segmentation model was approximately 30% smaller than that produced by the SMT system's training procedure, and gave an increase in transliteration quality measured in terms of both word accuracy and F-score.
Mutsumi KOMURO Norihisa KOMODA
Through the analysis of Rayleigh model, an explanatory model for the quality effect of peer reviews is constructed. The review activities are evaluated by the defect removal rate at each phase. We made hypotheses on how these measurements are related to the product quality. These hypotheses are verified through regression analysis of actual project data, and concrete calculation formulae are obtained as a model. Making use of the mechanism to construct this model, we can develop a method for making concrete review plan and setting objective values to manage on-going review activities.
Youl-Kyu SUH Sung-Hong WIE Hyun-Ho CHOI Dong-Ho CHO
In this paper, we analyze the performance of a bulk handoff scheme for mixed traffic in integrated voice/data wireless mobile networks in which new and handoff voice/data calls are accepted based on prioritization of handoff requests. If fewer channels than handoff calls are available in the target cell, some handoff calls are terminated without queuing. A higher priority is given to voice handoff calls than to data handoff calls. A multidimensional birth-death process model is presented to analyze the bulk handoff performance of mixed traffic. A numerical analysis of system performance is presented to evaluate the blocking probabilities of new voice and data calls, handoff failure probabilities, and the forced termination probabilities of voice/data handoff calls.
Yoshiyuki SHINKAWA Masao J. MATSUMOTO
It is one of the difficulties in enterprise modeling that we must deal with many fragmented pieces of knowledge provided by various domain-experts, which are usually based on mutually different viewpoints of them. This paper presents a formal approach to integrate those pieces into enterprise-wide model units using Rough Set Theory (RST). We focus on business processes in order to recognize and identify the constituents or units of enterprise models, which would compose the model expressing the various aspects of the enterprise. We defined five model unit types of "resource," "organization," "task," "function," and "behavior. " The first three types represent the static aspect of the enterprise, whereas the last two types represent the dynamic aspect of it. Those units are initially elicited from each domain-expert as his/her own individual model units, then they are integrated into enterprise-wide units using RST. Our approach is methodology-free, and any methodologies can include it in their early stage to identify what composes the enterprise.
This paper reports the application results of the state-of-the-art advanced process/device modeling to the 0.13 [µm] CMOS design solution. It has been demonstrated that the S/D-extension junction depth, the well profile, the channel profile and the drive current of the 0.13 [µm] CMOS can be predicted with reasonable accuracy. Further model improvement is required to predict the ΔL and the Vt-Lg characteristics of the devices with the tilted pocket I/I more accurately. It is quite beneficial to construct several design maps by using the state-of-the-art advanced TCAD in a 'carpet bombing' way in the early stage of the development of new generation CMOS.
Yoshiyuki SHINKAWA Masao J. MATSUMOTO
Adaptability evaluation of software systems is one of the key concerns in both software engineering and requirements engineering. In this paper, we present a formal and systematic approach to evaluate adaptability of software systems to requirements in enterprise business applications. Our approach consists of three major parts, that is, the common modeling method for both business realms and software realms, functional adaptability evaluation between the models with Σ algebra and behavioral adaptability evaluation with process algebra. By our approach, one can rigorously and uniquely determine whether a software system is adaptable to the requirements, either totally or partially. A sample application from an order processing is illustrated to show how this approach is effective in solving the adaptability evolution problem.
Hajimu IIDA Yoshihiro OKADA Katsuro INOUE Koji TORII
Marc Kellner proposed an example problem intending to compare modeling and describing techniques of software process. In this paper, we will describe our approach to understanding and describing the problem, from a process/product relation view, and synchronization/concurrent view. Also, we will show that a description of the problem is translated for execution and its correctness is validated.