ppxscal/embedding_network huggingface dataset:
Context-Aware Writing in Ubiquitous Learning Environments
Authors: Tzung-Shi Chen, Cheng-Sian Chang, Jeng-Shian Lin, Hui-Ling Yu
Venue: Proceedings of the Fifth IEEE International Conference on Wireless, Mobile, and Ubiquitous Technology in Education (2008)

With the popularization of the wireless network, and the progress of mobile computing technology, the efficiency of the hand-held device is better, and its applications are wider. Combining hand-held device and E-learning will be the main learning method in the future. This research employs wireless network, hand-held device, and RFID to build Context-Aware Writing System (C-Writing for short) in ubiquitous learning environments. After the learner using the C-Writing in the ubiquitous learning environment actually, we evaluate the result of learning by their works with/without C-Writing. We use the questionnaire to evaluate the learning situations; here the questionnaire contains the content of the users’ attitudes, system acceptance, system quality, content quality, and interactive with environment. The result of research shows most of the students approve this system’s benefit, and he/she is willing to use similar system in the future. Learners can efficient improve learning performance and attract attention of learners through this system.
Second-order symmetric duality with cone constraints
Authors: T. R. Gulati, S. K. Gupta, I. Ahmad
Venue: Journal of Computational and Applied Mathematics (2008)

Wolfe and Mond-Weir type second-order symmetric duals are formulated and appropriate duality theorems are established under @h-bonvexity/@h-pseudobonvexity assumptions. This formulation removes several omissions in an earlier second-order primal dual pair introduced by Devi [Symmetric duality for nonlinear programming problems involving @h-bonvex functions, European J. Oper. Res. 104 (1998) 615-621].
A Context-Aware Push-to-Talk Service
Authors: Jenq-Muh Hsu, Wei-Bin Lain, Jui-Chih Liang
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

Push-to-Talk (PTT) is a one-way voice group communication. It is very simple and easy to operate the PTT conversation. A talker presses the “talk” button of a PTT session to speak and the other group members in the same PTT session will simultaneously hear the talk at one time. The PTT has also been widely used in practical military, police, security, rescue, and emergency radio communications for many years. PTT service is also annunciated in mobile telecommunication, it is called Push-to-Talk over Cellular (PoC). Context-awareness is a mechanism to present the state information of users, devices, or environments according to their situations. Thus, a user can obtain a reasonable and proper service among these context-aware interactions. It is also extensively used in personal mobile communication for designing a ubiquitous communicating environment in many researches. In this paper we will combine the features of PTT and context-aware service to design a context-aware Push-to-Talk service. The PTT service can be aware to filter context information and to form an applicable PTT session according to the current contexts of PTT users.
Research on Context-Aware Mobile Computing
Authors: Li Han, Salomaa Jyri, Jian Ma, Kuifei Yu
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

Context-aware mobile computing belongs to the field of ubiquitous computing. It aims to enable device to provide better service for people through applying available context information. In this paper, context-aware mobile computing was elaborated. Firstly, the history of definition of context was summarized, and then the new classification of human-centric context was proposed. The acquiring and application of context information was generalized in the following part. On the basis, the issues in context-aware mobile computing were pointed out and finally the architecture of context-aware Q&A service was presented. Although the context-aware Q&A service can not solve all the issues introduced in this paper, it can be considered as an attempt to provide mobile service through mining of previously gathered context information sensed.
A transactional approach to lock scalability
Authors: Amitabha Roy, Keir Fraser, Steven Hand
Venue: Proceedings of the twentieth annual symposium on Parallelism in algorithms and architectures (2008)

Most software transactional memory implementations execute code using fine-grained optimistic concurrency control. This does not perform well with low contention data structures where fine grained conflict detection means manipulating metadata for every object touched and optimistic concurrency control imposes the overhead of making thread private shadow copies. Also, a purely optimistic approach does not coexist naturally with legacy code that is either already concurrent using locks or does IO operations that cannot be revoked. We try to address these problems by presenting a new form of the reader writer locks used by the vast majority of concurrent code today. Along with the traditional lock/unlock operations, these new locks support STM-like management of shadow versions that can be used when desired by the programmer. We show how existing lock based code can be scaled to perform as well as an STM, with few changes to the existing code base. We also show as a corollary that our design allows construction of data structures that retain strict fairness between threads, while simultaneously allowing disjoint access parallelism.
Positive solutions for nonlinear first-order periodic boundary value problems of impulsive dynamic equations on time scales
Authors: Da-Bin Wang
Venue: Computers Mathematics with Applications (2008)

In this paper, existence criteria of positive solutions to a class of nonlinear first-order periodic boundary value problems of impulsive dynamic equations on time scales are obtained. The main tool used in this paper is the well-known Guo-Krasnoselskii fixed-point theorem.
Scalable regular expression matching on data streams
Authors: Anirban Majumder, Rajeev Rastogi, Sriram Vanama
Venue: Proceedings of the 2008 ACM SIGMOD international conference on Management of data (2008)

Regular Expression (RE) matching has important applications in the areas of XML content distribution and network security. In this paper, we present the end-to-end design of a high performance RE matching system. Our system combines the processing efficiency of Deterministic Finite Automata (DFA) with the space efficiency of Non-deterministic Finite Automata (NFA) to scale to hundreds of REs. In experiments with real-life RE data on data streams, we found that a bulk of the DFA transitions are concentrated around a few DFA states. We exploit this fact to cache only the frequent core of each DFA in memory as opposed to the entire DFA (which may be exponential in size). Further, we cluster REs such that REs whose interactions cause an exponential increase in the number of states are assigned to separate groups -- this helps to improve cache hits by controlling the overall DFA size. To the best of our knowledge, ours is the first end-to-end system capable of matching REs at high speeds and in their full generality. Through a clever combination of RE grouping, and static and dynamic caching, it is able to perform RE matching at high speeds, even in the presence of limited memory. Through experiments with real-life data sets, we show that our RE matching system convincingly outperforms a state-of-the-art Network Intrusion Detection tool with support for efficient RE matching.
Fully strained Si0.75Ge0.25 epitaxial films with HfSiO gate dielectrics for high mobility channel metal-oxide semiconductor devices
Authors: Jungwoo Oh, Prashant Majhi, Raj Jammy, Raymond Joe, Takuya Sugawara, Yasushi Akasaka, Takanobu Kaitsuka, Tsunetoshi Arikado, Masayuki Tomoyasu
Venue: Microelectronic Engineering (2008)

The authors report on fully strained Si"0"."7"5Ge"0"."2"5 metal-oxide-semiconductor capacitors with HfSiO"2 high-k gate dielectric and TaN metal gate fabricated on Si substrates. Fully strained Si"0"."7"5Ge"0"."2"5 films are directly grown on Si substrates below the critical thickness. HfSiO"2 high-k gate dielectrics exhibit an equivalent oxide thickness of 13-18A with a permittivity of 17.7 and gate leakage current density lower than SiO"2 gate oxides by >100x. Interfacial oxide of the HfSiO"2/Si"0"."7"5Ge"0"."2"5 stack consists primarily of SiO"2 with a small amount of Ge and Hf. High performance SiGe field effect transistors are highly manufacturable with excellent electrical characteristics afforded by the fully strained HfSiO"2/SiGe gate stack.
Safety and Dependability Analysis of Self-Adaptive Systems
Authors: Matthias Güdemann, Frank Ortmeier, Wolfgang Reif
Venue: Proceedings of the Second International Symposium on Leveraging Applications of Formal Methods, Verification and Validation (2006)

In this paper we present a technique for safety analysis of self-adaptive systems with formal methods. Self-adaptive systems are characterized by the ability to dynamically (self-)adapt and reorganize. The aim of this approach is to make the systems more dependable. But in general it is unclear how big the benefit is compared to a traditional design. We propose a dependability analysis based on the results of safety analysis to measure the quality of self-x capabilities of an adaptive system with formal methods. This is important for unbiased and evidence-based decision making in early design phases. To illustrate the results we show the application of the method to a case study from the domain of production automation.
Instantaneous frequency estimation of FM signals using the T - class of time-frequency distributions
Authors: Zahir M. Hussain
Venue: Proceedings of the 4th WSEAS International Conference on Signal Processing, Computational Geometry & Artificial Vision (2004)

Recently we have proposed the T-class of time-frequency distributions (TFD's) with time-only kernels to provide high-resolution and considerable cross-terms reduction for multicomponent FM signals. In this work we investigate the instantaneous frequency (IF) properties of two members of this class: the hyperbolic and the exponential T-distributions in the presence of noise. A comparison with two well-known TFD's, Wigner-Ville and Choi-Williams distributions, is also considered.
Return to Babel: Emergent Diversity, Digital Resources, and Local Knowledge
Authors: Robin Boast, Michael Bravo, Ramesh Srinivasan
Venue: The Information Society (2007)

Information system research that recognizes, supports, and enables access of diverse knowledge communities online has become a major concern. Of particular concern is how these digital resources can support and preserve local identities and promote grass-roots involvement in creating the infrastructure of devolved governance. The aim of this article is to expose some of the conceptual obstacles to programs of devolved and local knowledge resources, and to provide an account of agency that recognizes that online communities, and community identity, are essential for eliciting, managing, and sharing local knowledges. Further, this article demonstrates how the implications of these issues impact institutions for managing knowledge that may be extended to all sorts of knowledge communities.
ICA mixture model algorithm for unsupervised classification of remote sensing imagery
Authors: C. A. Shah, P. K. Varshney, M. K. Arora
Venue: International Journal of Remote Sensing (2007)

Conventional remote sensing classification algorithms assume that the data in each class can be modelled using a multivariate Gaussian distribution. As this assumption is often not valid in practice, conventional algorithms do not perform well. In this paper, we present an independent component analysis (ICA)-based approach for unsupervised classification of multi/hyperspectral imagery. ICA used for a mixture model estimates the data density in each class and models class distributions with non-Gaussian (sub-and super-Gaussian) probability density functions, resulting in the ICA mixture model (ICAMM) algorithm. Independent components and the mixing matrix for each class are found using an extended information-maximization algorithm, and the class membership probabilities for each pixel are computed. The pixel is allocated to the class having maximum class membership probability to produce a classification. We apply the ICAMM algorithm for unsupervised classification of images obtained from both multispectral and hyperspectral sensors. Four feature extraction techniques are considered as a preprocessing step to reduce the dimensionality of the hyperspectral data. The results demonstrate that the ICAMM algorithm significantly outperforms the conventional K-means algorithm for land cover classification produced from both multi-and hyperspectral remote sensing images.
Artificial boundary method for two-dimensional Burgers' equation
Authors: Xiaonan Wu, Jiwei Zhang
Venue: Computers Mathematics with Applications (2008)

The numerical solution of the two-dimensional Burgers equation in unbounded domains is considered. By introducing a circular artificial boundary, we consider the initial-boundary problem on the disc enclosed by the artificial boundary. Based on the Cole-Hopf transformation and Fourier series expansion, we obtain the exact boundary condition and a series of approximating boundary conditions on the artificial boundary. Then the original problem is reduced to an equivalent problem on the bounded domain. Furthermore, the stability of the reduced problem is obtained. Finally, the finite difference method is applied to the reduced problem, and some numerical examples are given to demonstrate the feasibility and effectiveness of the approach.
The Adaptive Heartbeat Design of High Availability RAID Dual-Controller
Authors: Yaping Wan, Dan Feng, Tianming Yang, Ze Deng, Li Liu
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

Designing storage systems to provide high availability in the face of failures needs the use of various data protection techniques, such as dual-controller RAID. The failure of RAID controller may cause RAID storage system to fail to respond to ongoing requests and to no longer be available to new requests. Heartbeat is used to detect controllers whether survival. So, the heartbeat cycle’s impact on the high availability of a dual-controller hot–standby system has become the key of current research. To address the problem of fixed setting heartbeat in building high availability system currently, a self-adaptive heartbeat model of dual-controller which can adjust heartbeat cycle based on the frequency of data read-write request, is designed to improve the high availability of dual-controller RAID storage system. Based on this model, the high availability stochastic Petri net model of fault detection was established and used to evaluate the effect of the availability. In addition, we define a SHA (Self-adaptive Heart Ability) parameter to scale the ability of system heartbeat cycle to adapt to the environment when high availability system is at a changing environment of read and write requests. The results show that, relatively speaking with fixed configuration, the design can enhance dual controller RAID system high availability.
Modeling and Analyzing of a Time-Triggered Protocol for Automotive Systems
Authors: Bo Zhang
Venue: Proceedings of the Third International Conference on Systems (2008)

One of the distinguished features of a time-triggered communication protocol is that activities in the system are triggered by the passage of time, and the system time schedule is deterministic. Motivated by this property of a time-triggered protocol, we propose the synchronous timed streams concept, which can be viewed as an extension of the timed streams concept in the FOCUS modeling language. We show how the synchronous timed streams concept can effectively capture the essential communication mechanism of the FlexRay communication protocol -- a time-triggered communication protocol for automotive systems.
Scalable locking and recovery for network file systems
Authors: Peter J. Braam
Venue: Proceedings of the 2nd international workshop on Petascale data storage: held in conjunction with Supercomputing '07 (2007)

Petascale computing systems pose serious scalability challenges for any data storage system. Lustre is a scalable, secure, robust, highly-available cluster file system that has been successfully deployed on some of the largest supercomputing systems in the world, including the BlueGene/L supercomputer at the Lawrence Livermore National Laboratory (LLNL), the Red Storm supercluster at Sandia National Laboratories and the Jaguar supercomputer at the Oak Ridge National Laboratory. This paper provides file system developers with insight into how network file system scalability is addressed in the Lustre file system through policies and algorithms that support distributed lock management and options for facilitating recovery after a compute node failure in a large scale cluster. These design approaches can be applied to the scaling of other file systems to support large clusters.
Incident-Driven Memory Snapshot for Full-Virtualized OS Using Interruptive Debugging Techniques
Authors: Ruo Ando, Youki Kadobayashi, Youichi Shinoda
Venue: Proceedings of the 2008 International Conference on Information Security and Assurance (isa 2008) (2008)

Memory forensics is growing concern. For effective evidence retrieval, it is important to take snapshot timely. With proper modification of guest OS, VMM is powerful tool for timely snapshot. In this paper, we propose anincident-driven memory snapshot for full-virtualized OS using interruptive debugging techniques. We modify debug register handler to invoke snapshot facility of VMM. Software interrupt or signal are generated in register handler. Then, we can take snapshot asynchronously when debug register is changed. On guest OS, we apply three kinds of interruptive debugging techniques: driver supplied callback function, DLL injection. IDT (interruption descriptor table) is modified by driver supplied callback function, which makes it possible to cope with vulnerability exploitation. DLL injection is applied to insert security check function into a resource access function. Proposed system is implemented XEN virtual machine monitor and KVM (KernelVirtual machine).
Cooperative transmit-power estimation under wireless fading
Authors: Murtaza Zafer, Bongjun Ko, Ivan Wang-Hei Ho
Venue: Proceedings of the 9th ACM international symposium on Mobile ad hoc networking and computing (2008)

We study blind estimation of transmission power of a node based on received power measurements obtained under wireless fading. Specifically, the setup consists of a set of monitors that measure the signal power received from the transmitter, and the goal is to utilize these measurements to estimate the transmission power in the absence of any prior knowledge of the transmitter's location or any statistical distribution of its power. Towards this end, we exploit spatial diversity in received-power measurements and cooperation among the multiple monitoring nodes; based on theoretical analysis we obtain the Maximum Likelihood (ML) estimate, derive fundamental geometrical insights and show that this estimate is asymptotically optimal. Finally, we provide numerical results comparing the performance of the estimators through simulations and on a data-set of field measurements.
A Novel License Distribution Mechanism in DRM System
Authors: Qingcheng Li, Jin Zhang, Xiaoli Gong, Zhenhua Zhang
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

Recently, distribution is required in many DRM systems. However current distribution mechanisms appear to use restriction for distribution. In this paper, we propose a distribution mechanism based on using different licenses for different distributions. Particularly, we focus on taking interference to replace restriction and using degressive secret keys chain to control superdistribution. Advertisements are introduced as interference for compensation. More and more advertisements are shown as the distribution process furthers. And this mechanism can work in both off-line and on-line situations since secret keys in licenses are transformed directly.
Semantic-supported and agent-based decentralized grid resource discovery
Authors: Liangxiu Han, Dave Berry
Venue: Future Generation Computer Systems (2008)

One of the open issues in grid computing is efficient resource discovery. In this paper, we propose a novel semantic-supported and agent-based decentralized grid resource discovery mechanism. Without overhead of negotiation, the algorithm allows individual resource agents to semantically interact with neighbour agents based on local knowledge and to dynamically form a resource service chain to complete a task. The algorithm ensures the resource agent's ability to cooperate and coordinate on neighbour knowledge requisition for flexible problem solving. The developed algorithm is evaluated by investigating the relationship between the success probability of resource discovery and semantic similarity under different factors. The experiments show the algorithm could flexibly and dynamically discover resources and therefore provide a valuable addition to the field.
Quantum Arthur---Merlin games
Authors: Chris Marriott, John Watrous
Venue: Computational Complexity (2005)

This paper studies quantum Arthur---Merlin games, which are Arthur---Merlin games in which Arthur and Merlin can perform quantum computations and Merlin can send Arthur quantum information. As in the classical case, messages from Arthur to Merlin are restricted to be strings of uniformly generated random bits. It is proved that for one-message quantum Arthur---Merlin games, which correspond to the complexity class QMA, completeness and soundness errors can be reduced exponentially without increasing the length of Merlin's message. Previous constructions for reducing error required a polynomial increase in the length of Merlin's message. Applications of this fact include a proof that logarithmic length quantum certificates yield no increase in power over BQP and a simple proof that $$ {\text{QMA}} \subseteq {\text{PP}}. $$ Other facts that are proved include the equivalence of three (or more) message quantum Arthur---Merlin games with ordinary quantum interactive proof systems and some basic properties concerning two-message quantum Arthur---Merlin games.
Maximin D-optimal designs for binary longitudinal responses
Authors: Fetene B. Tekle, Frans E. S. Tan, Martijn P. F. Berger
Venue: Computational Statistics Data Analysis (2008)

Optimal design problems for logistic mixed effects models for binary longitudinal responses are considered. A function of the approximate information matrix under the framework of the Penalized Quasi Likelihood (PQL) and a generalized linear mixed model with autocorrelation is optimized. Locally D-optimal designs are computed. Maximin D-optimal designs are considered to overcome the problem of parameter value dependency of the D-optimal designs. The results show that the optimal number of repeated measurements depends on the number of regression parameters in the model. The performance of the maximin D-optimal designs in terms of the maximin efficiency (MME) is high for a range of parameter values that is common in practice. The design locations for mixed-effects logistic models generally shift to the left as compared to the design locations for general linear mixed-effects models known in the literature.