• Environmental Engineering Research
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• v.14 no.4
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• pp.200-210
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• 2009

The modern era of water quality modeling in the United States began in the 1960s. Pushed by advances in computer technology as well as environmental sciences, water quality modeling evolved through five broad periods: (1) initial model development with mainframe computers (1960s - mid 1970s), (2) model refinement and generalization with minicomputers (mid 1970s - mid 1980s), (3) model standardization and support with microcomputers (mid 1980s - mid 1990s), (4) better model access and performance with faster desktop computers running Windows and local area networks linked to the Internet (mid 1990s - early 2000s), and (5) model integration and widespread use of the Internet (early 2000s - present). Improved computer technology continues to drive improvements in water quality models, including more detailed environmental analysis (spatially and temporally), better user interfaces and GIS software, more accessibility to environmental data from on-line repositories, and more robust modeling frameworks linking hydrodynamics, water quality, watershed and atmospheric models. Driven by regulatory needs and advancing technology, water quality modeling will continue to improve to better address more complicated water bodies and pollutant types, and more complicated management questions. This manuscript describes historical trends in water quality model development in the United States, reviews current efforts, and projects promising future directions.

• International Journal of Internet, Broadcasting and Communication
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• v.9 no.4
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• pp.1-7
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• 2017

Clipart is artificial visual contents that are created using various tools such as Illustrator to highlight some information. Here, the style of the clipart plays a critical role in determining how it looks. However, previous studies on clipart are focused only on the object recognition [16], segmentation, and retrieval of clipart images using hand-craft image features. Recently, some clipart classification researches based on the style similarity using CNN have been proposed, however, they have used different CNN-models and experimented with different benchmark dataset so that it is very hard to compare their performances. This paper presents an experimental analysis of the clipart classification based on the style similarity with two well-known CNN-models (Inception Resnet V2 [13] and VGG-16 [14] and transfers learning with the same benchmark dataset (Microsoft Style Dataset 3.6K). From this experiment, we find out that the accuracy of Inception Resnet V2 is better than VGG for clipart style classification because of its deep nature and convolution map with various sizes in parallel. We also find out that the end-to-end training can improve the accuracy more than 20% in both CNN models.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.5
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• pp.2186-2203
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• 2020

Security administrators of companies and organizations need to come up with proper countermeasures against cyber-attacks considering infrastructures and security policies in their possession. In order to develop and verify such countermeasures, the administrators should be able to reenact both cyber-attacks and defenses. Simulations can be useful for the reenactment by overcoming its limitations including high risk and cost. If the administrators are able to design various scenarios of cyber-attacks and to develop simulation models from their viewpoints, they can simulate desired situations and observe the results more easily. It is challenging to simulate cyber-security issues, because there is lack of theoretical basis for modeling a wide range of the security field as well as pre-defined basic components used to model cyber-attacks. In this paper, we propose a modeling method for cyber-security simulations by developing a basic component and a composite model, called Abstracted Cyber-Security Unit Model (ACSUM) and Abstracted Cyber-security SIMulation model (ACSIM), respectively. The proposed models are based on DEVS(Discrete Event systems Specification) formalism, a modeling theory for discrete event simulations. We develop attack scenarios by sequencing attack behaviors using ACSUMs and then model ACSIMs by combining and abstracting the ACSUMs from a security perspective. The concepts of ACSUM and ACSIM enable the security administrators to simulate numerous cyber-security issues from their viewpoints. As a case study, we model a worm scenario using ACSUM and simulate three types of simulation models based on ACSIM from a different security perspective.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.83-92
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• 2013

Software globalization is the supporting process of adapting computer software to different country and culture. Most efforts for software globalization have been focused on the development of software implementation techniques or tools. However, global software sold worldwide has different requirements implied by different contexts, and the difference of requirements may derive different architectural design. In this paper, we define such architectural design knowledge as knowledge models and propose a method for developing and using the knowledge models for software globalization. Also we use set-top box middleware systems for digital data broadcast to validate the applicability of the proposed models and methods.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.3
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• pp.1034-1051
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• 2016

Mobility models are invaluable for determining the performance of routing protocols in opportunistic networks. The movement of nodes has a significant influence on the topological structure and data transmission in networks. In this paper, we propose a new mobility model called the campus-based community mobility model (CBCNM) that closely reflects the daily life pattern of students on a real campus. Consequent on a discovery that the pause time of nodes in their community follows a power law distribution, instead of a classical exponential distribution, we abstract the semi-Markov model from the movement of the campus nodes and analyze its rationality. Then, using the semi-Markov algorithm to switch the movement of the nodes between communities, we infer the steady-state probability of node distribution at random time points. We verified the proposed CBCNM via numerical simulations and compared all the parameters with real data in several aspects, including the nodes' contact and inter-contact times. The results obtained indicate that the CBCNM is highly adaptive to an actual campus scenario. Further, the model is shown to have better data transmission network performance than conventional models under various routing strategies.

• Journal of Internet Computing and Services
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• v.5 no.1
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• pp.41-49
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• 2004

Analytical performance evaluation is crucial for justifying the merit of the design of Multistage Interconnection Networks(MINs) in different operational conditions. While several analytical models have been proposed for the performance evaluation of MlNs, they are mainly for uniform traffics. Even the models for nonuniform traffics have various shortcomings. In this paper, an accurate model for the performance evaluation of multi buffered banyan-type MIN's under nonuniform traffic condition is obtained. The accuracy of proposed models are conformed by comparing with the results from simulation.

• Journal of Internet Computing and Services
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• v.19 no.2
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• pp.43-48
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• 2018

Various artifacts that are produced as software R&D project progresses contain research plan, research report, software requirements and design descriptions, etc. When conducting a software R&D project, it is necessary to confirm that the developed system has implemented its research requirements well. However, various research results make it difficult to design appropriate tests. So, there is a practical need for us to comprehensively handle the planning, execution, and reporting of software test for finding and verifying information related to the research. In this paper, we propose a useful method for software test process in R&D project which supports model based software testing. The proposed method supports automation of test design and generation of test data by explicitly separating each step of System Under Test (SUT). The method utilizes the various models representing the control flow of the function to extract the information necessary for testing the system. And it supports a systematic testing process based on TMMi and ISO 29119. Finally, we show the validity of the method by implementing a prototype with basic functionality to generate test data from software behavioral models.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.10
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• pp.4042-4059
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• 2020

The development of new multimedia techniques such as 3D printing is increasingly attracting the public's attention towards 3D objects. An optimized robust and imperceptible watermarking method based on Ant Colony Optimization (ACO) and Weber Law is proposed for 3D polygonal models. The proposed approach partitions the host model into smaller sub meshes and generates a secret watermark from the sub meshes using Weber Law. ACO based optimized strength factor is identified for embedding the watermark. The secret watermark is embedded and extracted on the wavelet domain. The proposed scheme is robust against geometric and photometric attacks that overcomes the synchronization problem and authenticates the secret watermark from the distorted models. The primary characteristic of the proposed system is the flexibility achieved in data embedding capacity due to the optimized strength factor. Extensive simulation results shows enhanced performance of the recommended framework and robustness towards the most common attacks like geometric transformations, noise, cropping, mesh smoothening, and the combination of such attacks.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.113-118
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• 2011

Sequence homology analysis in the substances in the phenomenon of life is to create database by sorting and indexing and to demonstrate the usefulness of informatics. In this paper, Markov models are used in GenScan program to convert the pattern of complex eukaryotic protein sequences. It becomes impossible to navigate the minimum distance, complexity increases exponentially as the exact calculation. It is used scorecard in amino acid substitutions between similar amino acid substitutions to have a differential effect score, and is applied the Markov models sophisticated concealment of the transition probability model. As providing superior method to translate sequences homologous sequences in analysis using blast p, Markov models. is secreted protein structure of sequence translations.

• Journal of Internet Computing and Services
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• v.4 no.5
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• pp.43-49
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• 2003

Analytical performance evaluation is crucial for justifying the merit of the design in different operational conditions. While several analytical models have been proposed for the performance evaluation of Multistage Interconnection Networks(MINs), they are mainly for uniform traffics. Even models for nonuniform traffics have several shortcomings such as they only consider output buffered structure or do not consider blocking conditions. In this paper the mere accurate models than any other ones so far have been proposed for the performance evaluation of banyan-type MIN's under nonuniform traffic condition is obtained. The accuracy of proposed model is conformed by comparing with the results from simulation.