ppxscal/embedding_network huggingface dataset:
An ontology-based approach to project-based learning
Authors: Lam-for Kwok, Ching-hang Cheung
Venue: Proceedings of the 10th IASTED International Conference on Computers and Advanced Technology in Education (2007)

Project-based Learning (PBL) involves searching, understanding, organising and applying a large amount of learning resources in solving a problem. PBL for a team encourages the sharing of learning resources and peer communication within the project team. There are many PBL system implementations which lack centralized learning resources management. This paper proposes an ontological knowledge structure in managing the collected learning resources and a mechanism to help organising these learning resources into a structure representing the project domain knowledge in order to fulfill the learning objectives of the designated project.
Minimizing Power Consumption with Performance Efficiency Constraint in Web Server Clusters
Authors: Yan Yang, Naixue Xiong, Ailixier Aikebaier, Tomoya Enokido, Makoto Takizawa
Venue: Proceedings of the 2009 International Conference on Network-Based Information Systems (2009)

Energy efficiency has become a very important issue to reduce the consumption of resources on the Earth. We have to consider how to save the energy consumption anywhere and anytime, including a large set of servers, for example, servers in the Google company. Hence, power and energy consumption has recently become key concerns, especially huge number of servers are deployed in large cluster configurations as in data centers and Web hosting facilities. Even though we emphasize power saving as much as possible, the performance of servers should be ensured. So far, there have been some discussions about enhancing power conservation. However, with the best of our knowledge, a mathematical model about consumed power and server’s performance has not been discussed. Therefore, in this paper, we attempted to minimize the energy consumption with performance constraint of web servers. We know, the response time is the focus of the performance in web servers. Therefore, we first find the trade off value of load for each server based on optimized methods. With the trade off load, the performance of users can be satisfied at the same time the power consumption is minimized. Then, using the trade off load value, we propose a novel load allocation method and then discuss the effectiveness of our load allocation method by comparing with other two methods: random load allocation method and average load allocation method.
Study on an Advance Order Tactic in a Two-Echelon Supply Chain
Authors: Jian-hu Cai, Li-ping Wang, Zu-feng Shao
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 01 (2009)

With the development of the information and internet technology, Vendor-Managed-Inventory (VMI) has been adopted by more and more companies. In this paper, a two-echelon supply chain inventory decision model is discussed. The products are perishable and sold over a single selling season. First a VMI model is constructed, and the supply chain members' optimal decisions are gained. Under VMI, the supplier takes charge of all inventory decisions and bears all inventory risk. Now an advance order tactic is introduced, under which the supplier gives the retailer a chance to place an advance order before the selling season. There are two wholesale prices after introducing the advance order tactic, and the retailer's optimal advance order quantities are different under different wholesale prices. The supply chain is coordinated by adjusting two wholesale prices. All our findings are illustrated by a numerical example.
Automatic seed set expansion for trust propagation based anti-spamming algorithms
Authors: Xianchao Zhang, Bo Han, Wenxin Liang
Venue: Proceeding of the eleventh international workshop on Web information and data management (2009)

Seed sets are of significant importance for trust propagation based anti-spamming algorithms, e.g., TrustRank. Conventional approaches require manual evaluation to construct a seed set, which restricts the seed set to be small in size, since it would cost too much and may even be impossible to construct a very large seed set manually. The small-sized seed set can cause detrimental effect on the final ranking results. Thus, it is desirable to automatically expand an initial seed set to a much larger one. In this paper, we propose the first automatic seed set expansion algorithm (ASE), which expands a small seed set by selecting reputable seeds that are found and guaranteed to be reputable through a joint recommendation link structure. Experimental results on the WEBSPAM-2007 dataset show that with the same manual evaluation efforts, ASE can automatically obtain a large number of reputable seeds with high precision, thus significantly improving the performance of the baseline algorithm in terms of both reputable site promotion and spam site demotion.
Image Error Concealment and Quality Access Control Based on Data Hiding and Cryptography
Authors: Amit Phadikar, Santi P. Maity, Claude Delpha
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 01 (2009)

This paper proposes a scheme that integrates error concealment and quality access control of digital image(s) in a single platform. The objective is achieved by embedding some important information extracted from the original image itself, to introduce sufficient redundancy in the transmitted image. The data embedding is done by modulating integer wavelet coefficients using quantization index modulation (QIM). Before data embedding the important information is encrypted using chaotic logistic mapping. The necessary information in the form of the secret key (K) is further encrypted using a public key (P) cryptology for its secret transmission to the receiver. The user who has the knowledge of the secret key (K) can decrypt the hidden information for the concealment purpose, while the users having different partial knowledge of the key (K) enjoy relative qualities of the images by partial recovery of the damaged region. The simulation results have shown the validity of both the claims.
Combining heuristic procedures and simulation models for balancing a PC camera assembly line
Authors: Ana R. Mendes, Ana L. Ramos, Ana S. Simaria, Pedro M. Vilarinho
Venue: Computers and Industrial Engineering (2005)

In this paper, a mixed-model PC camera assembly line balancing case study is presented. The aim of the study is to establish different line configurations, for varying levels of demand. In the first stage of the study, a heuristic procedure previously developed by some of the authors, based on the simulated annealing meta-heuristic, is used to derive line configurations with a minimum number of workstations and a smooth workload balance between and within the workstations. In the second stage, the solutions provided by the heuristic are used as an input to discrete event simulation models in which certain manufacturing parameters that analytical procedures have difficulty to accommodate, namely, stochastic times, machine breakdowns, rework, etc. are introduced. These simulation models derive different performance measures (e.g. flow times and resources utilization) that provide operational support and help fine-tune the line configurations. This paper reports on the collaborative study between the Department of Economics, Management and Industrial Engineering of University of Aveiro and a major manufacturer of electronic consumer goods.
The Strategy of Java Class File's Modification
Authors: Qing Su, Yongfeng Cao, Guoda Liang
Venue: Proceedings of the 2009 Second International Workshop on Computer Science and Engineering - Volume 01 (2009)

A modification strategy is given Java class file. It does not disobey the Java class file’s format, so the modified class files can be interpret any Java Virtual Machine products. It denotes the way how to add extra information into class file, which make common Java Virtual Machine products ignore them, but special Java Virtual Machine products may recognized them. Experimentation has put up to inspect the strategy.
Finding Your True IT Transformation
Authors: Peter Kraynak
Venue: IT Professional (2009)

If you want to transform your business and cause a dramatic improvement for the enterprise, you'll need to start by truly transforming your IT life cycle. It's easy to believe that IT is truly reinventing itself by hiring new people, installing new tools, or preaching a new methodology. However, providing transformational leadership starts with the leadership itself along with the development of the three core competencies of strategy, solutions, and implementation. Your job in IT leadership is to develop all three competencies in your organization by cultivating the necessary skills and techniques, and then to cause each of them to happen continuously and concurrently. When these changes become the organization's new habits, you're on the path to true transformation.
Ellipsis 3D: A particle-in-cell finite-element hybrid code for modelling mantle convection and lithospheric deformation
Authors: Craig O'Neill, Louis Moresi, Dietmar Müller, Rich Albert, Frédéric Dufour
Venue: Computers Geosciences (2006)

We have extended the two-dimensional geodynamics finite-element code ''Ellipsis'' to three-dimensions. Ellipsis uses a hybrid particle in a cell scheme, which combines a fixed mesh of computational points and a dense arrangement of mobile material points. The fixed Eulerian mesh allows very fast computation, performed in Ellipsis via a multigrid iteration method, while the Lagrangian particle reference frame allows the tracking of material interfaces and history-dependent properties such as strain history for strain-softening materials. The method is exceptionally useful in very large deformation analyses, where purely Lagrangian approaches would be severely hampered by the need for remeshing to minimize element distortion. The Gnu Public Licensed Ellipsis3D code lends itself to combined 2D/3D model prototyping, and has proven to be an excellent geodynamics teaching tool for modelling, covering mantle convection, lithospheric extension and plume-lithosphere interaction.
Modeling on integrated platform for logistics planning
Authors: Xiangdong Hu
Venue: Proceedings of the IASTED Asian Conference on Modelling and Simulation (2007)

Efficient and economical transportation and delivery operations are necessary and urgent for modern logistics service, the integrated platform for logistics planning is an important way out, which brings digital identity of cargos and optimized routing and scheduling plan together, the platform gives logistics planners an approach to make better decision faster and further to reach more revenue. The digitization method of cargos identity by two-dimensional barcode technology was introduced, hierarchical model for generating transportation plan was initially proposed, which is separated into routing, scheduling and cargo-loading three steps. The integrated platform for logistics planning can be computerized and an optimized plan of transportation and delivery operations can be automatically generated by it, and it can offer significant potential for cost decreases and productivity gains, the method is proved to be feasible and reliable.
Using inheritance in a metadata based approach to data quality assessment
Authors: José Farinha, Maria José Trigueiros, Orlando Belo
Venue: Proceeding of the first international workshop on Model driven service engineering and data quality and security (2009)

Currently available data quality tools provide development environments that significantly decrease the effort in dealing with common data problems, such as those related with attribute domain validation, syntax checking, or value matching against a reference master data repository. On the contrary, more complex and specific data quality functionalities, whose requirements usually derive from application domain business rules, have to be developed from scratch, usually leading to high costs of development and maintenance. This paper introduces the concept of inheritance in a metadata-driven approach to simplified data quality rule management. The approach is based on the belief that even complex data quality rules very often adhere to recurring patterns that can be encoded and encapsulated as reusable, abstract templates. The approach is supported by a metamodel developed on top of OMG's Common Warehouse Metamodel, herein extended with the ability to derive new rule patterns from existing ones, through inheritance. The inheritance metamodel is presented in UML and its application is illustrated with a running example.
GA-Based LSB-Matching Steganography to Hold Second-Order Statistics
Authors: Guangjie Liu, Zhan Zhang, Yuewei Dai, Zhiquan Wang
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 01 (2009)

How to design more secure steganographical algorithms all along is the hot topic. In this paper, a modified LSB-matching method is proposed to hold second-order statistics described by Markov Chain distance. To achieve it, the genetic algorithm is used to find the optimum tuning vector to match LSBs of image pixels and message bits. Experiments show the proposed algorithm has better security in K-L and M-C distance meanings, and the blind steanalysis tests also show that our new algorithm is more secure than LSB and LSB-matching methods
Scheduling in dynamic assembly job-shops to minimize the sum of weighted earliness, weighted tardiness and weighted flowtime of jobs
Authors: S. Thiagarajan, Chandrasekharan Rajendran
Venue: Computers and Industrial Engineering (2005)

In many manufacturing systems, jobs that are completed early are held as finished-goods inventory until their due-dates, and hence we incur earliness costs. Similarly, jobs that are completed after their due-dates incur penalty. The objective in such situations would, therefore, be to meet the due-dates of the respective jobs as closely as possible, and consequently minimize the sum of earliness and tardiness of jobs because earliness and tardiness of jobs greatly influence the performance of a schedule with respect to cost. In addition, a job incurs holding cost from the time of its arrival until its completion. Most studies on scheduling in such manufacturing systems assume unit earliness cost, unit tardiness cost and unit holding cost of a job. However, in reality such an assumption need not always hold and it is quite possible that there exist different costs of earliness, tardiness and holding for different jobs. In addition, most studies on job-shop scheduling assume that jobs are independent and that no assembly operations exist. The current study addresses the problem of scheduling in dynamic assembly job-shops (i.e. shops that manufacture multi-level jobs) with the consideration of jobs having different earliness, tardiness and holding costs. An attempt is made in this paper to present dispatching rules by incorporating the relative costs of earliness, tardiness and holding of jobs in the form of scalar weights. In the first phase of the study, relative costs (or weights for) earliness and tardiness of jobs are considered, and the dispatching rules are presented in order to minimize the sum of weighted earliness and weighted tardiness of jobs. In the second phase of the study, the objective considered is the minimization of the sum of weighted earliness, weighted tardiness and weighted flowtime of jobs, and the dispatching rules are presented by incorporating the relative costs of earliness, tardiness and flowtime of jobs. Simulation studies have been conducted separately for both phases of the current study, the performance of the scheduling rules have been observed independently, and the results of the simulation study have been reported. The proposed rules are found to be effective in minimizing the mean and maximum values of the measures of performance.
Performance analysis of transmit beamforming for MISO systems with imperfect feedback
Authors: Yogananda Isukapalli, Ramesh Annavajjala, Bhaskar D. Rao
Venue: IEEE Transactions on Communications (2009)

In this paper, we analyze the performance of transmit beamforming on multiple-antenna Rayleigh fading channels with imperfect channel feedback. We characterize the feedback imperfections in terms of noisy channel estimation, feedback delay, and finite-rate channel quantization. We develop a general framework, that is valid for an arbitrary two-dimensional linear modulation, to capture the aforementioned imperfections and derive the symbol and bit error probability expressions for both M-PSK and M-ary rectangular QAM constellations with Gray code mapping. We show that the proposed analytical formulation is valid for a frequency-domain duplexing system with/without finite-rate channel quantization and a time-domain duplexing system. We validate the accuracy of the analysis through simulations, and assess the relative effects of channel estimation inaccuracy, feedback delay, and finite-rate quantization on the symbol and bit error performances for various constellations.
Fingerprinting with minimum distance decoding
Authors: Shih-Chun Lin, Mohammad Shahmohammadi, Hesham El Gamal
Venue: IEEE Transactions on Information Forensics and Security (2009)

This paper adopts an information-theoretic framework for the design of collusion-resistant coding/decoding schemes for digital fingerprinting. More specifically, the minimum distance decision rule is used to identify 1 out of t pirates. Achievable rates, under this detection rule, are characterized in two scenarios. First, we consider the averaging attack where a random coding argument is used to show that the rate 1/2 is achievable with t = 2 pirates. Our study is then extended to the general case of arbitrary t highlighting the underlying complexity-performance tradeoff. Overall, these results establish the significant performance gains offered by minimum distance decoding compared to other approaches based on orthogonal codes and correlation detectors which can support only a subexponential number of users (i.e., a zero rate). In the second scenario, we characterize the achievable rates, with minimum distance decoding, under any collusion attack that satisfies the marking assumption. For t = 2 pirates, we show that the rate 1 - H (0.25) ≅ 0.188 is achievable using an ensemble of random linear codes. For t ≥ 3, the existence of a nonresolvable collusion attack, with minimum distance decoding, for any nonzero rate is established. Inspired by our theoretical analysis, we then construct coding/decoding schemes for fingerprinting based on the celebrated belief-propagation framework. Using an explicit repeat-accumulate code, we obtain a vanishingly small probability of misidentification at rate 1/3 under averaging attack with t = 2. For collusion attacks, which satisfy the marking assumption, we use a more sophisticated accumulate repeat accumulate code to obtain a vanishingly small misidentification probability at rate 1/9 with t = 2. These results represent a marked improvement over the best available designs in the literature.
A Survey of Security Middleware for Pervasive and Ubiquitous Systems
Authors: Jameela Al-Jaroodi, Alyaziyah Al-Dhaheri, Fatmah Al-Abdouli, Nader Mohamed
Venue: Proceedings of the 2009 International Conference on Network-Based Information Systems (2009)

Recently, pervasive and ubiquitous computing evolved tremendously and has become an integral part of many fields. This is widely attributed to their efficiency in integrating with everyday components and handling tasks in a faster and better way. As a result, technologies to facilitate their development, integration and security also evolved. Middleware is an essential component in this field and recently more emphasis has been put on security middleware as an enabling component for pervasive and ubiquitous applications. This is due to the high levels of personal and private data sharing in these systems. In this paper we survey some representative security middleware approaches and highlight their various properties and characteristics. We also discuss and compare these approaches in terms of their design, target environments, and main features. The review reveals that several options are available; however, there are still many issues and problems to be addressed to achieve more efficient security middleware.
Application of optimal control theory to product pricing and warranty with free replacement under the influence of basic lifetime distributions
Authors: Pei-Chun Lin, Li-Yen Shue
Venue: Computers and Industrial Engineering (2005)

This study investigates optimal policies for determining price and warranty length when free replacement of defective items is the business policy and the demand is dependent on price, warranty, and cumulative sales. We apply optimal control theory to a profit-maximization model that takes into consideration the expected warranty cost per item. The maximization of market values is based on a pre-determined life cycle and spans across both expansion and saturation phases of the market. We further investigate the optimal policies for a number of basic lifetime distributions, when the demand function is under the setting of separable and logistic growth. We found that as the growth of a product enters different phases of the market, optimal decision policies are characterized by simultaneously increasing or reducing both price and warranty length.
Lock step: an algorithm to reduce Wi-Fi Jitter
Authors: Hong Lin, David McDonald
Venue: IEEE Communications Letters (2009)

The exponential backoff algorithm used in IEEE 802.11 does not guarantee short term fairness between flows. We propose an algorithm based on IdleSense where each of N flows tries to transmit every W = 8N slots; i.e. 8 slots per flow with 7 idle. Each flow adaptively adjusts its contention window W based on the observed proportion of empty slots. One key aspect of Lock Step is setting a deterministic backoff after a successful transmission so that, for persistent flows, eventually all users are in lock step and transmit every 8N slots. Another key aspect is forcing a second collision between colliding users so all users can better estimate the proportion of idle slots per transmission thus allowing users to estimate N and hence the optimal backoff. This second collision can also be engineered to assist the ZigZag algorithm to decode the colliding packets. Even with transient flows Lock Step reduces jitter and can substantially increase the number of flows carrying Voice over IP traffic through a single access point.
Potential collaboration discovery using document clustering and community structure detection
Authors: Cristian Klen dos Santos, Alexandre Gonçalves Evsukoff, Beatriz S.L.P. de Lima, Nelson Francisco Favilla Ebecken
Venue: Proceeding of the 1st ACM international workshop on Complex networks meet information & knowledge management (2009)

Complex network analysis is a growing research area in a wide variety of domains and has recently become closely associated with data, text and web mining. One of the most active areas in the study of complex networks is the detection of community structure, which can be related to the clustering problem in data mining. This paper employs a community structure detection algorithm for document clustering in order to discover potential relationships in a social network. The proposed approach is explored in a case study of potential collaboration discovery among the research staff in the Graduate Civil Engineering Department of the Federal University of Rio de Janeiro, Brazil. The results show that the combined use of both techniques provides useful insights on the relationships, both existent and potential, among individuals in the social network.