• Title/Summary/Keyword: Challenging work

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Large-Scale Integrated Network System Simulation with DEVS-Suite

  • Zengin, Ahmet
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.4
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    • pp.452-474
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    • 2010
  • Formidable growth of Internet technologies has revealed challenging issues about its scale and performance evaluation. Modeling and simulation play a central role in the evaluation of the behavior and performance of the large-scale network systems. Large numbers of nodes affect simulation performance, simulation execution time and scalability in a weighty manner. Most of the existing simulators have numerous problems such as size, lack of system theoretic approach and complexity of modeled network. In this work, a scalable discrete-event modeling approach is described for studying networks' scalability and performance traits. Key fundamental attributes of Internet and its protocols are incorporated into a set of simulation models developed using the Discrete Event System Specification (DEVS) approach. Large-scale network models are simulated and evaluated to show the benefits of the developed network models and approaches.

An Intelligent 2D Secret Share Construction using Visual Cryptography for Secure Transmission

  • Kumar, N. Rajesh;Krishnan, R. Bala;Manikandan, G.;Raajan, N.R.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.7
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    • pp.2862-2878
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    • 2020
  • Data Security is the most challenging area in Internet communication, where most of the secret sharing schemes are proposed for binary images. But still it lacks in providing security for data communication, especially in image transmission. Traditional visual cryptography scheme generate meaningless diwies and the reconstruction phase leads to quality degradation over the secret image. In this work, an intelligent two dimensional secret share construction scheme is proposed. A secret image is expanded into n diwies with the choice of scheme selection. By Stacking all the qualified diwies to revert the secret image without content loss and less than s* - 1 shares could not reveal any information about the secret image. The experimental results emphasize that the proposed secret share scheme is highly secured for image transmission.

Identification of neoantigens derived from alternative splicing and RNA modification

  • Park, Jiyeon;Chung, Yeun-Jun
    • Genomics & Informatics
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    • v.17 no.3
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    • pp.23.1-23.6
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    • 2019
  • The acquisition of somatic mutations is the most common event in cancer. Neoantigens expressed from genes with mutations acquired during carcinogenesis can be tumor-specific. Since the immune system recognizes tumor-specific peptides, they are potential targets for personalized neoantigen-based immunotherapy. However, the discovery of druggable neoantigens remains challenging, suggesting that a deeper understanding of the mechanism of neoantigen generation and better strategies to identify them will be required to realize the promise of neoantigen-based immunotherapy. Alternative splicing and RNA editing events are emerging mechanisms leading to neoantigen production. In this review, we outline recent work involving the large-scale screening of neoantigens produced by alternative splicing and RNA editing. We also describe strategies to predict and validate neoantigens from RNA sequencing data.

The Importance of Human Resource Management in New International Logistics Environment (신 국제물류환경과 인적관리의 중요성)

  • 김진환
    • Journal of Korea Port Economic Association
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    • v.17 no.1
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    • pp.113-128
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    • 2001
  • The modem world has brought a wave of changes, not the least of which is globalization or what is often referred to as the "borderless society." In recent times, changes in the global business environment, such as trade deregulation and advances in technology, are challenging us to find new ways of thinking about and coping with these new forces. The field of global logistics has encountered a host of paradigm shifts as well. Therefore, it is critical that managers involved in international logistics take into account perceptional swift or at least understand the value of fully utilizing information. The appropriate management of human resources is a key factor in dealing with not only new information technology, but also shifts in the business environment. In particular, it will be important for Korea's logistics managers at international logistics companies to continually work to develop themselves, as they must carry out a critical role in global supply chain management. If they fail to take heed of the demand's of the new environment, the competitiveness of Korean enterprises in international logistics will suffer severely.

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Product Family Design using Formal Concept Analysis and Ontology (정형적 개념 분석과 온톨로지를 활용한 제품계열 정보 설계)

  • Lee, Hee-Jung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.35 no.3
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    • pp.110-117
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    • 2012
  • A product family design has received much attention over the last several decades, since a product family-based development shortens lead-times and reduces cost, as well as increases efficiency and effectiveness of the product realization process. It is challenging work, however, to define the product family design in the heterogeneous product development environments, due to myriads of products related information described in different ways across products in any companies. In this paper, we provided a way of defining product family design framework using formal concept analysis and ontology language. Based on this, the specific product family can be derived by ontological reasoning, and the new product concept can be also expanded in the framework. The proposed framework is formalized using OWL (Web Ontology Language) and implemented in $Prot{\acute{e}}g{\acute{e}}$. Actual product family design algorithm is carried out using FaCT++ engine, a plug-in to $Prot{\acute{e}}g{\acute{e}}$, and the benefits of the proposed method are also demonstrated through a case study.

Nanolithography Using Haptic Interface in a Nanoscale Virtual Surface (햅틱인터페이스를 이용한 나노스케일 가상표면에서의 나노리소그래피)

  • Kim Sung-Gaun
    • Journal of Surface Science and Engineering
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    • v.39 no.2
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    • pp.64-69
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    • 2006
  • Nanoscale task such as nanolithography and nanoindenting is a challenging work that is beyond the capabilities of human sensing and precision. Since surface forces and intermolecular forces dominate over gravitational and other more intuitive forces of the macro world at the nanoscale, a user is not familiar with these novel nanoforce effects. In order to overcome this scaling barrier, haptic interfaces that consist of visual and force feedback at the macro world have been used with an Atomic Force Microscope (AFM) as a manipulator at the nanoscale. In this paper, a nanoscale virtual coupling (NSVC) concept is introduced and the relationship between performance and impedance scaling factors of velocity (or position) and force are explicitly represented. Experiments have been performed for nanoindenting and nanolithography with different materials in the nanoscale virtual surface. The interaction forces (non contact and contact nanoforces) between the AFM tip and the nano sample are transmitted to the operator through the haptic interface.

Extended Trigger Modelling for the Workflow Analysis and Design: Case of Telecommunication Company (워크플로 분석/설계를 위한 확장 트리거 모델링: 전화국 사례)

  • Han, Dong-Il;Park, Sei-Kwon
    • IE interfaces
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    • v.9 no.3
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    • pp.236-248
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    • 1996
  • Most of business enterprises today struggle with the coordination of work which is one of the most challenging problems in the business environment. And the situation becomes worse by the increasing complexity and uncertainty. In this paper, suitability of workflow technology for the modelling, optimization, and automation in the complex business structures is discussed. Also, in the abscence of a fully fledged method for analysis and design of workflow systems, this paper proposes a method, ETM(Extended Trigger Modelling), which can solve several problems in other methods. The proposed ETM approach consists of three stages such as situation analysis stage, activity coordination stage and implementation preparation stage. A modelling case of the proposed procedure is also presented.

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Potential of regression models in projecting sea level variability due to climate change at Haldia Port, India

  • Roshni, Thendiyath;K., Md. Sajid;Samui, Pijush
    • Ocean Systems Engineering
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    • v.7 no.4
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    • pp.319-328
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    • 2017
  • Higher prediction efficacy is a very challenging task in any field of engineering. Due to global warming, there is a considerable increase in the global sea level. Through this work, an attempt has been made to find the sea level variability due to climate change impact at Haldia Port, India. Different statistical downscaling techniques are available and through this paper authors are intending to compare and illustrate the performances of three regression models. The models: Wavelet Neural Network (WNN), Minimax Probability Machine Regression (MPMR), Feed-Forward Neural Network (FFNN) are used for projecting the sea level variability due to climate change at Haldia Port, India. Model performance indices like PI, RMSE, NSE, MAPE, RSR etc were evaluated to get a clear picture on the model accuracy. All the indices are pointing towards the outperformance of WNN in projecting the sea level variability. The findings suggest a strong recommendation for ensembled models especially wavelet decomposed neural network to improve projecting efficiency in any time series modeling.

Aggregation multigrid method for schur complement system in FE analysis of continuum elements

  • Ko, Jin-Hwan;Lee, Byung Chai
    • Structural Engineering and Mechanics
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    • v.30 no.4
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    • pp.467-480
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    • 2008
  • An aggregation multigrid method (AMM) is a leading iterative solver in solid mechanics. Recently, AMM is applied for solving Schur Complement system in the FE analysis of shell structures. In this work, an extended application of AMM for solving Schur Complement system in the FE analysis of continuum elements is presented. Further, the performance of the proposed AMM in multiple load cases, which is a challenging problem for an iterative solver, is studied. The proposed method is developed by combining the substructuring and the multigrid methods. The substructuring method avoids factorizing the full-size matrix of an original system and the multigrid method gives near-optimal convergence. This method is demonstrated for the FE analysis of several elastostatic problems. The numerical results show better performance by the proposed method as compared to the preconditioned conjugate gradient method. The smaller computational cost for the iterative procedure of the proposed method gives a good alternative to a direct solver in large systems with multiple load cases.

A Survey of QoS Based Routing Protocols for Wireless Sensor Networks

  • Sumathi, R.;Srinivas, M.G.
    • Journal of Information Processing Systems
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    • v.8 no.4
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    • pp.589-602
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    • 2012
  • With the increasing demand for real time applications in the Wireless Senor Network (WSN), real time critical events anticipate an efficient quality-of-service (QoS) based routing for data delivery from the network infrastructure. Designing such QoS based routing protocol to meet the reliability and delay guarantee of critical events while preserving the energy efficiency is a challenging task. Considerable research has been focused on developing robust energy efficient QoS based routing protocols. In this paper, we present the state of the research by summarizing the work on QoS based routing protocols that has already been published and by highlighting the QoS issues that are being addressed. The performance comparison of QoS based routing protocols such as SAR, MMSPEED, MCMP, MCBR, and EQSR has also been analyzed using ns-2 for various parameters.