ppxscal/embedding_network huggingface dataset:
Binary Documents Recovery Based on Skeleton Extraction
Authors: Chu-Hsing Lin, Jung-Chun Liu, Lun-Yuen Cheng, Jung-Jung Chung
Venue: Proceedings of the 2009 Third International Conference on Multimedia and Ubiquitous Engineering (2009)

In the ubiquitous computing environment, digital media is widespread fast and interweaving into our everyday lives. As an effective method to achieve copyright protection of digital media, digital watermarking technology has been widely used in multimedia, such as images, videos, and audios, and other areas such as binary documents, which has been explored extensively in recent years. In this paper, we propose a new method to protect and recover binary document images from tampering. Black skeletons are calculated and then information is embedded in the host file. The embedded information can be extracted from the embedded file later to compare with the original black skeletons for file verification. The experimental results show that our proposed method is effective in detecting locations of tampered data and recovering binary document images.
A 2-D ESPO Algorithm and Its Application in Pedestrian Path Planning Considering Human Behavior
Authors: Zheng Pan, Lei Yan, Adam C. Winstanley, A. Stewart Fotheringham, Jianghua Zheng
Venue: Proceedings of the 2009 Third International Conference on Multimedia and Ubiquitous Engineering (2009)

A 2-D Euclidean shortest path with obstacles (ESPO) algorithm for pedestrian navigation is developed. ESPO is a classical algorithm in the field of computational geometry. We describe some common ESPO algorithms and discuss their application in pedestrian shortest path determination based on the generation of a network of paths within a polygon with interior obstacles. This algorithm can be applied to pedestrian navigation in open spaces, such as squares, parks and big halls. Path generation is based on the Dijkstra algorithm, which is extended to solve the path planning problem not only for path and road networks but also for open spaces. The algorithm takes human preferences based on walking conditions into account and can find different paths with minimum cost for different conditions. The results of this approach are illustrated through an experimental system. Further work to integrate the algorithm into a practical pedestrian navigation system is proposed.
Encoder Rate Control for Pixel-Domain Distributed Video Coding without Feedback Channel
Authors: Baoguo Du, Hong Shen
Venue: Proceedings of the 2009 Third International Conference on Multimedia and Ubiquitous Engineering (2009)

Distributed Video Coding (DVC) is a new video coding technique which has low encoder complexity and good error resilience. Rate control is one of the most important problems in DVC. In order to allocate an optimal number of parity bits for the current frame,most distributed video coders use a feedback channel(FC) to perform rate control at the decoder. However,using feedback channel can increase the decoding complexity and result in transmission delay. To solve these problems, we propose a novel encoder rate control (ERC) algorithm for pixel-domain distributed video (PDDV) coder without feedback channel at the cost of slightly increased encoder complexity. The experiment results show that the performance obtained using our ERC algorithm is comparable to that obtained using the decoder rate control (DRC)algorithm. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Spatial Characteristics of Walking Areas for Pedestrian Navigation
Authors: Jianghua Zheng, Adam Winstanley, Zheng Pan, Seamus Coveney
Venue: Proceedings of the 2009 Third International Conference on Multimedia and Ubiquitous Engineering (2009)

We consider how to handle open walking areas in pedestrian navigation applications. Walking areas are a key type of feature which is a major difference betweennetworks of pedestrian navigation and that of road vehiclenavigation. Up to recently, little work has been carried outon these features though they are important to routeplanning algorithm design and path representation forpedestrian navigation. Characteristics of walking areas are classified into three types with orthogonal attributes, including the character of boundaries and entrances, concavo-convex characteristics of shapes and the presence and numbers of islands. The possible combinations are identified and general solutions proposed. Future work including the extension to 3D navigation in buildings and trials in mobile applications are proposed.
A simple dual-mode limited feedback multiuser downlink system
Authors: Chun Kin Au-Yeung, Seung Young Park, David J. Love
Venue: IEEE Transactions on Communications (2009)

Generally limited feedback systems that multiplex multiple user signals are noise power limited in the low signal-to-noise-ratio (SNR) regime and interference power limited in the high SNR regime. If the amount of feedback does not grow with SNR, then there is a sum rate ceiling that increasing the transmit power alone cannot surpass. This paper proposes a simple dual mode system where the base station serves either one user or as many users as the number of transmit antennas. The switching mechanism is smooth and is based on instantaneous system conditions. The mobile determines its preferred transmission mode by using a very simple signal-to-interference-and-noise-ratio (SINR) threshold. Based on the mobiles' feedback, the base station chooses the method of signalling accordingly. With a finite number of feedback bits per mobile, it is shown that the proposed system achieves close to the maximum of the sum-rate for single user and multiuser modes. We identify the preferrable mode for an asymptotically large number of users and/or SNR. This proposed architecture is suitable for systems with moderate coherence time, a moderate to large number of users, and a moderate SNR that cannot afford complex processing at the base station or at the mobile.
Attitudes to the application of a Web-based learning system in a microbiology course
Authors: Italo Masiello, Robert Ramberg, Kirsti Lonka
Venue: Computers Education (2005)

Computer-based systems have great potential for delivering learning material. Here, a Web-based learning management system is employed by a medical university to support undergraduate courses. The objective was to help the university's staff to understand the readiness and attitudes of students to the use of information technology, their orientation to new learning environments, and the functionality of the system. The participants were a cohort of first-year medical students enrolled in an introductory microbiology course. Students' attitudes to information technology and learning styles were measured by a rearranged questionnaire, and a principal component analysis identified the students' orientations to information technology and the learning environment. The results of the study revealed that students showed readiness to and positive attitudes towards information technology in education and exposed a possible benefit from its use in the long run. However, they also conveyed negative opinions of the learning management system used in their coursework, suggesting a need for change of the technology. This study provides evidence that in order for computer-based system to be effective they must be designed and implemented with care, otherwise they may risk to lower students' interests and activation.
A GIS tool for hydrogeological water balance evaluation on a regional scale in semi-arid environments
Authors: I. Portoghese, V. Uricchio, M. Vurro
Venue: Computers Geosciences (2005)

A GIS tool to evaluate hydrogeological water balance based on a mass-balance model applied to surface and subsurface systems is discussed. The tool is designed for managers responsible for groundwater resource planning during conditions of water shortage. In developing the tool, the natural groundwater recharge was evaluated through the application of a soil water balance equation, and defined as the difference between the inflows (rainfall, irrigation) and the outflows (plant evapotranspiration, surface run-off). A distributed approach was used in the soil water balance equation to account for the spatial variability of climate and landscape features. Conversely the groundwater balance was calculated on a watershed or aquifer scale, using a lumped water balance equation, in which withdrawals for different uses were estimated together with inflows from other water bodies and coastal outflows. The model was implemented on a GIS platform with an automatic routine that manages all the data sets required and allows for the forecasting of groundwater storage volumes. Furthermore, the model was able to evaluate agricultural water demands under different climatic and management scenarios. A tool which provides a summary of the results and performs a statistical analysis for any portion of the study area was also implemented. The model was applied to a coastal region of Southern Italy. The averaged groundwater balance calculated by the model was in agreement with the piezometric head and chlorine concentration trends measured in selected monitoring wells.
The Simulation for the SIP DDoS Attack
Authors: Chung-Hsin Liu, Chun-Lin Lo
Venue: Proceedings of the 2009 Fifth International Joint Conference on INC, IMS and IDC (2009)

This study is focus on SIP of VoIP, and simulated and analysised by NS2. In addition, because of the security issues are the main factor to affect its popularization, and the DDOS attack has become one of the more serious issues in VoIP network security domain. Therefore this research carries on the simulation analysis to various types attack by NS2, and further discusses under the DDoS attack between each kind of Queue regarding the attack comparison of bearing capacity.
An approach for spherical harmonic analysis of non-smooth data
Authors: Hansheng Wang, Patrick Wu, Zhiyong Wang
Venue: Computers Geosciences (2006)

A method is proposed to evaluate the spherical harmonic coefficients of a global or regional, non-smooth, observable dataset sampled on an equiangular grid. The method is based on an integration strategy using new recursion relations. Because a bilinear function is used to interpolate points within the grid cells, this method is suitable for non-smooth data; the slope of the data may be piecewise continuous, with extreme changes at the boundaries. In order to validate the method, the coefficients of an axisymmetric model are computed, and compared with the derived analytical expressions. Numerical results show that this method is indeed reasonable for non-smooth models, and that the maximum degree for spherical harmonic analysis should be empirically determined by several factors including the model resolution and the degree of non-smoothness in the dataset, and it can be several times larger than the total number of latitudinal grid points. It is also shown that this method is appropriate for the approximate analysis of a smooth dataset. Moreover, this paper provides the program flowchart and an internet address where the FORTRAN code with program specifications are made available.
Multiclass, multistage, and multilevel fiber-optic CDMA signaling techniques based on advanced binary optical logic gate elements
Authors: Babak M. Ghaffari, Jawad A. Salehi
Venue: IEEE Transactions on Communications (2009)

In this paper we introduce and propose novel signaling methods and receiver structures based on advanced binary optical logic gates for fiber-optic code division multiple access (FO-CDMA) systems using all-optical signal processing. In the proposed system the users of the network are categorized into multiple classes. Users of each class transmit at the same power level but different from the levels of the other classes' users. Using a combination of optical OR, AND and XNOR logic gates for the receiver structure we show that such a network not only takes the full advantages of all-optical signal processing but also demonstrates a considerable throughput efficiency when compared to ordinary FO-CDMA systems. The proposed receiver structure mitigates the effect of interfering users from the other classes by rejecting some specified power level combinations from the other classes. The depth of interference cancellation is a function of the corresponding number of power levels and the number of stages applied to the optical logic gates in use. In our analysis we choose the generalized form of optical orthogonal codes (OOC), i.e., OOCs with cross-correlation value greater than one, as the signature sequence. We begin by emphasizing on two-level systems, that is, when the users can select one out of two power levels for signal transmission. However, for multilevel FO-CDMA we obtain a closed-form relation for the upper bound on the probability of error. We will show that under the ideal case the increase in throughput resulting from the proposed multilevel system is proportional to the number of classes or power levels in use. Our analytical results are compared to the results of an extensive system simulation. The numerical closeness between, the analytical and system simulation, indicates the accuracy with which we have modeled mathematically our proposed signaling using advanced binary optical logic gates in FO-CDMA.
An object oriented approach to the description and simulation of watershed scale hydrologic processes
Authors: Jun Wang, James M. Hassett, Theodore A. Endreny
Venue: Computers Geosciences (2005)

An object-oriented design (OOD) approach is used to describe watershed scale hydrologic processes. Individual objects (or processes) at multiple levels are described using the 'inheritance' concept, while the interactions of objects (or processes) are described using the 'aggregation' concept. This design methodology is applied to create the new watershed based hydrological model OBJTOP (OBJect oriented, TOPographic based model). In OBJTOP, the watershed (top level object) is composed of five sub-objects: precipitation, evapotranspiration, vegetation, soil and channel. These objects are further subdivided, such as soil into four sub-objects: surface, and root, unsaturated and saturated zones. Each sub-object, designed using the inheritance concept, has its own distinct attributes and behaviors and works independently to represent different individual processes such as soil processes, channel processes, etc. The sub-objects, designed using the aggregation principle, are interconnected and interact with each other within the higher level objects and thus constitute the hydrological process simulation. OBJTOP presents a description of hydrologic processes in a direct and concise manner. OBJTOP's model structure should benefit model coding, maintenance, and future modification efforts, and therefore the program design strategies should be of interest to other program designers.
Detection of Image Region Duplication Forgery Using Model with Circle Block
Authors: Junwen Wang, Guangjie Liu, Hongyuan Li, Yuewei Dai, Zhiquan Wang
Venue: Proceedings of the 2009 International Conference on Multimedia Information Networking and Security - Volume 01 (2009)

Due to the widespread use of sophisticated imaging tools, digital image forgeries have already become a serious social problem. In this paper, we proposes an efficient and robust algorithm for detection of a specific category of digital image forgery known as region duplication forgery, which is done by copying a block of an image and pasting it on to some other block of the same image. The image is first reduced in dimension by Gaussian pyramid, and four features are adopted for each circle block. The feature vectors are lexicographically sorted. Then similar vectors will be matched by a certain threshold value. Finally, the area threshold value is proposed to remove the wrong similar blocks. Experimental results show that our method is robust to not only the post processing including noise adding, blurring, lossy compression, but also the copy region rotation. Meanwhile, the proposed method reduces the total number of blocks to narrow block-matching searching space, which can improve the efficiency comparing with the exiting methods.
Design of low-rate irregular LDPC codes using trellis search
Authors: Sang Hyun Lee, Kwang Soon Kim
Venue: IEEE Transactions on Communications (2009)

A simple design method using trellis search is proposed for good low-density parity-check (LDPC) codes with relatively low code rates. By applying a trellis search technique to the design of a pre-assigned part of the parity-check matrix that allows a simple encoding, we improve the distribution of cycles formed by the entries contained in the parity-check part of the parity-check matrix. In addition, we extend the proposed algorithm to a class of structured LDPC codes, which have been recently preferred in many practical applications. Simulation results show that the codes designed by the proposed method outperform those constructed by conventionally used greedy design algorithms.
Buffer allocation plan for a remanufacturing cell
Authors: Hasan Kivanc Aksoy, Surendra M. Gupta
Venue: Computers and Industrial Engineering (2005)

We present a near optimal buffer allocation plan (NOBAP) specifically developed for a remanufacturing cell with finite buffers and unreliable servers. A remanufacturing cell is a self-reliant entity within which a variety of activities such as disassembly, inspection, material processing, remanufacturing, assembly and transportation are performed. The remanufacturing cell considered in this paper consists of three modules, viz. the disassembly and testing module for returned products, the disposition module for non-reusable returns and the remanufacturing module. We propose an algorithm that uses an open queueing network, decomposition principle and expansion methodology to analyze the remanufacturing cell. The buffer allocation algorithm distributes a given number of available buffer slots among the various stations (across the various modules) to optimize the cell's performance. The algorithm has been rigorously tested for both balanced and unbalanced cells. The results show that the performance of the algorithm is consistent, robust and produces excellent results in a variety of experimental conditions.
Sentence Similarity Computation Based on POS and Semantic Nets
Authors: Ming Che Lee, Jia Wei Zhang, Wen Xiang Lee, Heng Yu Ye
Venue: Proceedings of the 2009 Fifth International Joint Conference on INC, IMS and IDC (2009)

This paper presents a novel sentence similarity computation algorithm. The proposed algorithm is based on the concepts of part-of-speech (POS) and the WordNet semantic nets. Unlike other related researches that focused only on short sentences, our algorithm is applicable to short (4-5 words), medium (8-12 words), and even long sentences (over 12 words). The experiment demonstrates that the proposed algorithm has outstanding performance in handling with long sentences with complex syntax. The significance of this research lies in the semantic similarity extracting of word sets with different part-of-speeches. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
On the performance of selection decode-and-forward relay networks over Nakagami-m fading channels
Authors: Trung Q. Duong, Vo Nguyen Quoc Bao, Hans-Jürgen Zepernick
Venue: IEEE Communications Letters (2009)

In this paper, we present the performance of fixed decode-and-forward cooperative networks with relay selection over independent but not identically distributed Nakagamim fading channels, with integer values of the fading severity parameter m. Specifically, closed-form expressions for the symbol error probability and the outage probability are derived using the statistical characteristic of the signal-to-noise ratio. We also perform Monte-Carlo simulations to verify the analytical results.
Scalability of indexing structures in a production systems testbed for computational research
Authors: Scott Moses, Le Gruenwald
Venue: Computers and Industrial Engineering (2005)

This paper analyzes the scalability of indexing structures in a production systems testbed for large-scale computational research on discrete build-to-order environments. The testbed consists of five integrated services that interoperate for order entry, order promising, production planning, execution, and control. The service-based architecture is Java-based, object-oriented, event-driven, memory-resident, and multi-threaded. Services in the testbed very frequently need to rapidly locate specified elements in their large data models during algorithmic computations, and in that regard a number of indexing structures have been designed by computer scientists with the purpose of increasing the efficiency of data access. We explore the tradeoff between improved application scalability and increased implementation complexity of indexing structures by comparing the B+-tree, T-tree, and R-tree indexing structures to a simple and widely used linear structure in the context of an application to real-time order promising. Scalability is evaluated by measuring space requirements and the computational time as a function of the size of the system.
Improved quality of e-learning at lower cost
Authors: Paul Kawachi
Venue: Proceedings of the 10th IASTED International Conference on Computers and Advanced Technology in Education (2007)

Many students in developing regions have poor infrastructure and narrow bandwidth unsuitable for most new high-end technological developments. Here we report improved quality of learning and distributed knowledge construction achieved using only the most rudimentary internet. We have converted free blog software and service into a networked synchronous discussion board. which allows multi-user connectivity and interactivity either in small groups in class (using peer-review and tutor guidance, commentary, negotiated syllabus and assessment) or in distance education linking together any number of users simultaneously or asynchronously in a shared learning context. High-end learning management systems at preventive high cost, and occasional sudden downtown for servicing, are obsolescent, and email service is redundant. Students, teachers, administrators, other stakeholders, and invited (or uninvited) experts can collaborate to generate new shared knowledge -- not unlike wikis, but by far simpler, with clear authoring capabilities to allow immediate feedback online assessment. We have combined this with student annotations in any number of languages to suit the learner alongside the pre-constructed content -- as well as for the shared content under construction - delivered online to develop a system for three-times better quality of learning at a reduced cost to the institution, teacher and student.
On the Mutual information distribution of MIMO rician fading channels
Authors: Yonglan Zhu, Pooi-Yuen Kam, Yan Xin
Venue: IEEE Transactions on Communications (2009)

In a fading environment, the statistical distribution of the mutual information of a multiple-input multiple-output (MIMO) system depends on the joint distribution of the eigenvalues of a Wishart matrix, and is quite complex in general. We obtain here simple expressions for the distributions of the determinant and the trace of a Wishart matrix. Based on the obtained distributions, we derive some simple and tight bounds on the complementary cumulative distribution function (CCDF) of the mutual information of a MIMO system in Rician fading environments. The bounds obtained on the CCDF of mutual information provide further insights into the channel mutual information, and show the effects of the system parameters on the mutual information distribution explicitly. In addition, results for the Rayleigh channels are obtained as a special case.