bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPLEXITY AND THE MULTIPLE IMPACTS ON NEW PRODUCT DEVELOPMENT: RESULTS FROM A FIELD STUDY
Authors: KIM JONGBAE , WILEMON DAVID
Published: April 2013

Most technology-based product development programs are becoming more complex and difficult to manage. New technologies, increasingly knowledgeable customers, partnered development projects, differentiated global markets, and more sophisticated product development practices make corporate innovation initiatives especially challenging. The factors that make new product development (NPD) projects complex can impact both NPD processes and performance. Unfortunately, the relationships between complexity and NPD processes and performance are not well-understood. Our study is based on 32 in-depth field interviews with NPD project participants regarding their experiences dealing with complexity. Our interviews were specifically aimed at understanding the consequences to NPD projects when complexity issues arise; whether complexity affects interpersonal relationships within development teams; and what complexity issues, if any, are created when development teams work with alliances and partners. Our research also seeks to understand if significant competitive advantages can be attained by firms from their ability to effectively manage complex new products. After presenting our findings, we construct a comprehensive model to help explain complexity and its potential impacts on NPD. We then develop several implications for product development managers and their teams regarding how to manage complexity. We posit that for technology-based organizations, "managing development complexity", is a critical core competency. We conclude our work with suggestions for future research.
DEVELOPMENT OF MAGNETICALLY RESPONSIVE Fe3O4@C CORE/SHELL MICROSPHERES AS POTENTIAL VECTORS FOR DRUG-DELIVERY APPLICATIONS
Authors: YUAN WENJING , ZHU LING , CHEN PING , XIE ANJIAN , ZHANG HUI , WANG CUIPING , SHEN YUHUA
Published: March 2013

The Fe3O4@C core/shell microspheres were fabricated via a two-step process. Fe3O4 microspheres were firstly prepared, and Fe3O4@C core/shell microspheres were subsequently fabricated using glucose as a carbon source by a hydrothermal route, in which the thickness of the carbon coating was about 20 nm. The resulting products were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR). The Nitrogen adsorption–desorption isotherms reveal their mesoporous structure and larger BET surface area (62.3 m2g-1). The Fe3O4@C core/shell microspheres possess ferromagnetism and high saturation magnetization (39.2 emu ⋅ g-1). Bovine hemoglobin (BHb) was used as a model protein to test the adsorption and desorption properties of the Fe3O4@C core/shell microspheres. The capacity for BHb adsorption was more than 71.3 mg/g. According to the values obtained in the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay the Fe3O4@C core/shell microspheres show a low toxicity. Therefore, the prepared Fe3O4@C core/shell microspheres are of great significance for guided site-specific drug delivery.
EFFECTS OF ULTRASONIC RADIATION INTENSITY ON THE OXIDATION OF SINGLE-WALLED CARBON NANOTUBES IN A MIXTURE OF SULFURIC AND NITRIC ACIDS
Authors: HE RUI , PEI XIBO , PAN LANLAN , TIAN LINGYANG , LUO FENG , SUI LEI , WAN QIANBING , WANG JIAN
Published: April 2013

One of the most commonly used techniques for purification and eventual dispersion of single-wall carbon nanotubes (SWNTs) is oxidation using strong acid and ultrasonication. Literature review reveals that ultrasonication of varying radiation intensities have been used during the acid oxidation, but few have reported whether ultrasonication of different intensities would have different effects on the structure and properties of SWNTs and how the effects are. An investigation of the effects of ultrasonic radiation intensity on SWNTs during oxidation in a mixture of sulfuric and nitric acids was conducted. Ultrasonication using different intensities (50 W, 100 W, 200 W and 300 W) was used. The acid-treated SWNTs were characterized by scanning and transmission electron microscopy, Fourier transform infrared spectroscopy, zeta potential test Boehm titration test and Raman spectrum analysis. Data from these experiments showed that high intensities provided stronger oxidizing conditions than lower ones. As ultrasonic intensity increased, larger number of SWNTs were destroyed and consumed to produce carbonaceous impurities, and more defects appeared in the tube walls.
FLEXIBLE ORGANIC/INORGANIC MOISTURE BARRIER USING PLASMA-POLYMERIZED LAYER
Authors: SEO SEUNG-WOO , CHUNG HO KYOON , CHAE HEEYEOP , SEO SANG JOON , CHO SUNG MIN
Published: March 2013

We report a multilayer moisture barrier structure comprised of alternating inorganic aluminum oxide and plasma-polymerized organic layers. The inorganic and organic layers were grown by atomic layer deposition (ALD) and plasma polymerization in vacuum, respectively. The inclusion of plasma-polymerized layers in the multilayer barrier structure enhanced the moisture barrier performance by around 15% for as-deposited samples. After being subjected to 10 000 bending cycles with a bending radius of 2 cm, however, the moisture barrier performance of the multilayer structure was improved by 50% from that of pure inorganic counterpart.
VARIABLE SELECTION FOR PARTIALLY LINEAR VARYING COEFFICIENT QUANTILE REGRESSION MODEL
Authors: DU JIANG , ZHANG ZHONGZHAN , SUN ZHIMENG
Published: April 2013

In this paper, we propose a variable selection procedure for partially linear varying coefficient model under quantile loss function with adaptive Lasso penalty. The functional coefficients are estimated by B-spline approximations. The proposed procedure simultaneously selects significant variables and estimates unknown parameters. The major advantage of the proposed procedures over the existing ones is easy to implement using existing software, and it requires no specification of the error distributions. Under the regularity conditions, we show that the proposed procedure can be as efficient as the Oracle estimator, and derive the optimal convergence rate of the functional coefficients. A simulation study and a real data application are undertaken to assess the finite sample performance of the proposed variable selection procedure.
REMARKS ABOUT ORTHOGONAL MATCHING PURSUIT ALGORITHMS
Authors: XU ZHIQIANG
Published: April 2013

The orthogonal matching pursuit (OMP) is a popular decoder to recover sparse signal in compressed sensing. Our aim is to investigate the theoretical properties of OMP. In particular, we show that the OMP decoder can give (p, q) instance optimality for a large class of encoders with 1 ≤ p ≤ q ≤ 2 and (p, q) ≠ (2, 2).
ETHANOL SENSOR OF CdO/Al2O3/CeO2 OBTAINED FROM Ce-DOPED LAYERED DOUBLE HYDROXIDES WITH HIGH RESPONSE AND SELECTIVITY
Authors: XU DONGMEI , GUAN MEIYU , XU QINGHONG , GUO YING , WANG YAO
Published: April 2013

In this paper, Ce -doped CdAl layered double hydroxide (LDH) was first synthesized and the derivative CdO/Al2O3/CeO2 composite oxide was prepared by calcining Ce -doped CdAl LDH. The structure, morphology and chemical state of the Ce doped CdAl LDH and CdO/Al2O3/CeO2 were also investigated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), solid state nuclear magnetic resonance (SSNMR), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The gas sensing properties of CdO/Al2O3/CeO2 to ethanol were further studied and compared with CdO/Al2O3 prepared from CdAl LDH, CeO2 powder as well as the calcined Ce salt. It turns out that CdO/Al2O3/CeO2 sensor shows best performance in ethanol response. Besides, CdO/Al2O3/CeO2 possesses short response/recovery time (12/72 s) as well as remarkable selectivity in ethanol sensing, which means composite oxides prepared from LDH are very promising in gas sensing application.
COMBINATORIAL PREPARATION AND FERROELECTRIC PROPERTIES OF COMPOSITIONALLY GRADIENT PZT THIN FILMS
Authors: HE GANG , PENG CHAO , HE MINGZHONG , HONG JIANHE , LI HAIFENG , GONG YANSHENG
Published: March 2013

Using a combinatorial synthesis process, compositionally gradient PZT thin films were conveniently prepared by a chemical solution decomposition (CSD) method. The thin films showed a perovskite structure with (111)-preferred orientation and a thickness of around 450 nm. The surface morphology and ferroelectric properties were significantly different, depending on the direction of compositional gradient. The detailed composition and gradient of the composition was seen to affect the property of compositionally gradient PZT thin films. The gradient thin film PZT654, with a Zr:Ti ratio of 6:4 at the bottom of the film nearest to the substrate, and with an total composition around the morphotropic phase boundary (MPB, x = 0.52) showed favorable ferroelectric properties. However, no typical offset of the hysteresis loops was observed in our work.
J-TYPE DIPOLE STACKING AND STRONG π-π INTERACTIONS IN THE CRYSTALS OF DISTYRYLBENZENE DERIVATIVES: THE CRYSTAL STRUCTURES, HIGH LUMINESCENCE PROPERTIES AND PREDICTION OF HIGH MOBILITY
Authors: XIE ZENGQI , YANG BING , LIU LINLIN , MA YUGUANG
Published: March 2013

The crystal structures of three analogs of trans-DPDSB (2,5-diphenyl-1,4-distyrylbenzene with two trans double bonds) are very similar to that of rubrene, which have face-to-face molecular packing mode with relative displacement along the molecular long axis. The very strong intermolecular π-π interactions enable the crystal to have the potential of high charge-carrier mobility predicted by the theoretical calculations. Most important, the crystals of these materials have very high photoluminescence (PL) efficiency of about 50% due to the J-type dipole stacking, which is different from the crystal of rubrene. The crystal structures give the prediction of combining both high luminescence and high mobility in one crystal by constructing J-type dipole stacking with strong π-π interactions.
AGGREGATION-ENHANCED EMISSION OF DIBLOCK COPOLYMER CONTAINING TETRAPHENYLTHIOPHENE-QUINOLINE PENDANT FLUORPHORES BY SELECTIVE SOLVENT PAIRS
Authors: YANG CHIH-MIN , LAI CHUNG-TIN , CHEN TAI-LIN , CHIEN WEI-LUN , HONG JIN-LONG
Published: March 2013

PSQu-PBS in THF/hexane increase with the increasing hexane content. Copolymer micelles formed in THF/hexane mixtures are supposed to have higher extent of aggregation, leading to more pronounced AEE effect than micelles formed in THF/ H 2 O . Time-resolved fluorescence spectroscopy was conducted on PSQu-PBS and PSQu solutions to evaluate the respective lifetimes involved in the excited monomer and aggregated species and to compare the extent of aggregation in all sample solutions. Solid PSQu-PBS samples prepared from 80 vol.%- H 2 O and –hexane solutions of PSQu-PBS were then inspected by TEM to reveal their morphological difference and its influence on the extent of aggregation leading to the AIE effect.
Minimum transmission power configuration in real-time sensor networks with overlapping channels
Authors: Wang Xiaodong , Wang Xiaorui , Xing Guoliang , Yao Yanjun
Published: April 2013

Multi-channel communications can effectively reduce channel competition and interference in a wireless sensor network and thus achieve increased throughput and improved end-to-end delay guarantees with reduced power consumption. However, existing work relies only on a small number of orthogonal channels, resulting in degraded performance when a large number of data flows need to be transmitted on different channels. In this article, we conduct empirical studies to investigate interferences among overlapping channels. Our results show that overlapping channels can also be utilized for improved real-time performance if the node transmission power is carefully configured. In order to minimize the overall transmission power consumption of a network with multiple data flows under end-to-end delay constraints, we formulate a constrained optimization problem to configure the transmission power level of every node and assign overlapping channels to different data flows. Since the optimization problem has an exponential computational complexity, we then present a heuristic algorithm designed based on simulated annealing to find a suboptimal solution. Our extensive empirical results on a 33-mote testbed demonstrate that our algorithm achieves better real-time performance and less power consumption than two baselines, including a scheme using only orthogonal channels.
Energy-efficient data redistribution in sensor networks
Authors: Tang Bin , Jaggi Neeraj , Wu Haijie , Kurkal Rohini
Published: April 2013

We address the energy-efficient data redistribution problem in data-intensive sensor networks (DISNs). In a DISN, a large volume of data gets generated, which is first stored in the network and is later collected for further analysis when the next uploading opportunity arises. The key concern in DISNs is to be able to redistribute the data from data-generating nodes into the network under limited storage and energy constraints at the sensor nodes. We formulate the data redistribution problem where the objective is to minimize the total energy consumption during this process while guaranteeing full utilization of the distributed storage capacity in the DISNs. We show that the problem is APX-hard for arbitrary data sizes; therefore, a polynomial time approximation algorithm is unlikely. For unit data sizes, we show that the problem is equivalent to the minimum cost flow problem, which can be solved optimally. However, the optimal solution's centralized nature makes it unsuitable for large-scale distributed sensor networks. Thus, we design a distributed algorithm for the data redistribution problem which performs very close to the optimal, and compare its performance with various intuitive heuristics. The distributed algorithm relies on potential function-based computations, incurs limited message and computational overhead at both the sensor nodes and data generator nodes, and is easily implementable in a distributed manner. We analytically study the convergence and performance of the proposed algorithm and demonstrate its near-optimal performance and scalability under various network scenarios. In addition, we implement the distributed algorithm in TinyOS, evaluate it using TOSSIM simulator, and show that it outperforms EnviroStore, the only existing scheme for data redistribution in sensor networks, in both solution quality and message overhead. Finally, we extend the proposed algorithm to avoid disproportionate energy consumption at different sensor nodes without compromising the solution quality.
Optimizing sensor network reprogramming via in situ reconfigurable components
Authors: Taherkordi Amir , Loiret Frederic , Rouvoy Romain , Eliassen Frank
Published: April 2013

Wireless reprogramming of sensor nodes is a critical requirement in long-lived wireless sensor networks (WSNs) addressing several concerns, such as fixing bugs, upgrading the operating system and applications, and adapting applications behavior according to the physical environment. In such resource-poor platforms, the ability to efficiently delimit and reconfigure the necessary portion of sensor software—instead of updating the full binary image—is of vital importance. However, most existing approaches in this field have not been adopted widely to date due to the extensive use of WSN resources or lack of generality. In this article, we therefore consider WSN programming models and runtime reconfiguration models as two interrelated factors and we present an integrated approach for addressing efficient reprogramming in WSNs. The middleware solution we propose, <scp<RemoWare</scp<, is characterized by mitigating the cost of post-deployment software updates on sensor nodes via the notion of in situ reconfigurability and providing a component-based programming abstraction in order to facilitate the development of dynamic WSN applications. Our evaluation results show that <scp<RemoWare</scp< imposes a very low energy overhead in code distribution and component reconfiguration and consumes approximately 6% of the total code memory on a <scp<TelosB</scp< sensor platform.
Surface-level path loss modeling for sensor networks in flat and irregular terrain
Authors: Chong Poh Kit , Kim Daeyoung
Published: April 2013

Many wireless sensor network applications require sensor nodes to be deployed on the ground or other surfaces. However, there has been little effort to characterize the large- and small-scale path loss for surface-level radio communications. We present a comprehensive measurement of path loss and fading characteriztics for surface-level sensor nodes in the 400 MHz band in both flat and irregular outdoor terrain in an effort to improve the understanding of surface-level sensor network communications performance and to increase the accuracy of sensor network modeling and simulation. Based on our measurement results, we characterize the spatial small-scale area fading effects as a Rician distribution with a distance-dependent K-factor. We also propose a new semi-empirical path loss model for outdoor surface-level wireless sensor networks called the Surface-Level Irregular Terrain (SLIT) model. We verify our model by comparing measurement results with predicted values obtained from high-resolution digital elevation model (DEM) data and computer simulation for the 400 MHz and 2.4 GHz band. Finally, we discuss the impact of the SLIT model and demonstrate through simulation the effects when SLIT is used as the path loss model for existing sensor network protocols.
Object tracking in the presence of occlusions using multiple cameras
Authors: Ercan Ali O. , Gamal Abbas El , Guibas Leonidas J.
Published: April 2013

This article describes a sensor network approach to tracking a single object in the presence of static and moving occluders using a network of cameras. To conserve communication bandwidth and energy, we combine a task-driven approach with camera subset selection. In the task-driven approach, each camera first performs simple local processing to detect the horizontal position of the object in the image. This information is then sent to a cluster head to track the object. We assume the locations of the static occluders to be known, but only prior statistics on the positions of the moving occluders are available. A noisy perspective camera measurement model is introduced, where occlusions are captured through occlusion indicator functions. An auxiliary particle filter that incorporates the occluder information is used to track the object. The camera subset selection algorithm uses the minimum mean square error of the best linear estimate of the object position as a metric, and tracking is performed using only the selected subset of cameras.

Using simulations and preselected subsets of cameras, we investigate (i) the dependency of the tracker performance on the accuracy of the moving occluder priors, (ii) the trade-off between the number of cameras and the occluder prior accuracy required to achieve a prescribed tracker performance, and (iii) the importance of having occluder priors to the tracker performance as the number of occluders increases. We find that computing moving occluder priors may not be worthwhile, unless it can be obtained cheaply and to high accuracy. We also investigate the effect of dynamically selecting the subset of camera nodes used in tracking on the tracking performance. We show through simulations that a greedy selection algorithm performs close to the brute-force method and outperforms other heuristics, and the performance achieved by greedily selecting a small fraction of the cameras is close to that of using all the cameras.
Secure ad hoc trust initialization and key management in wireless body area networks
Authors: Li Ming , Yu Shucheng , Guttman Joshua D. , Lou Wenjing , Ren Kui
Published: April 2013

The body area network (BAN) is a key enabling technology in e-healthcare. An important security issue is to establish initial trust relationships among the BAN devices before they are actually deployed and generate necessary shared secret keys to protect the subsequent wireless communications. Due to the ad hoc nature of the BAN and the extreme resource constraints of sensor devices, providing secure as well as efficient and user-friendly trust initialization is a challenging task. Traditional solutions for wireless sensor networks mostly depend on key predistribution, which is unsuitable for a BAN in many ways. In this article, we propose
group device pairing
(GDP), a user-aided multi-party authenticated key agreement protocol. Through GDP, a group of sensor devices that have no pre-shared secrets establish initial trust by generating various shared secret keys out of an unauthenticated channel. Devices authenticate themselves to each other with the aid of a human user who performs visual verifications. The GDP supports fast batch deployment, addition and revocation of sensor devices, does not rely on any additional hardware device, and is mostly based on symmetric key cryptography. We formally prove the security of the proposed protocols, and we implement GDP on a sensor network testbed and report performance evaluation results.
Packet-level attestation (PLA)
Authors: Kamal Abu Raihan M. , Bleakley Chris , Dobson Simon
Published: April 2013

Wireless sensor networks (WSN) show enormous potential for collection and analysis of physical data in real-time. Many papers have proposed methods for improving the network reliability of WSNs. However, real WSN deployments show that sensor data-faults are very common. Several server-side data reliability techniques have been proposed to detect these faults and impute missing or erroneous data. Typically, these techniques reduce the lifetime of the network due to redundant data transmission, increase latency, and are computation and storage intensive. Herein, we propose Packet-Level Attestation (PLA), a novel framework for sensor data reliability assessment. It exploits the spatial correlation of data sensed at nearby sensors. The method does not incur additional transmission of control message between source and sink; instead, a verifier node sends a validation certificate as part of the regular data packet. PLA was implemented in TinyOS on TelosB motes and its performances was assessed. Simulations were performed to determine its scalability. It incurs only an overhead of 1.45% in terms of packets transmitted. Fault detection precision of the framework varied from 100% to 99.48%. Comparisons with existing methods for data reliability analysis showed a significant reduction in data transmission, prolonging the network lifetime.
A low-bandwidth camera sensor platform with applications in smart camera networks
Authors: Chen Phoebus , Hong Kirak , Naikal Nikhil , Sastry S. Shankar , Tygar Doug , Yan Posu , Yang Allen Y. , Chang Lung-Chung , Lin Leon , Wang Simon , Lobatón Edgar , Oh Songhwai , Ahammad Parvez
Published: April 2013

Smart camera networks have recently emerged as a new class of sensor network infrastructure that is capable of supporting high-power in-network signal processing and enabling a wide range of applications. In this article, we provide an exposition of our efforts to build a low-bandwidth wireless camera network platform, called CITRIC, and its applications in smart camera networks. The platform integrates a camera, a microphone, a frequency-scalable (up to 624 MHz) CPU, 16 MB FLASH, and 64 MB RAM onto a single device. The device then connects with a standard sensor network mote to form a wireless camera mote. With reasonably low power consumption and extensive algorithmic libraries running on a decent operating system that is easy to program, CITRIC is ideal for research and applications in distributed image and video processing. Its capabilities of in-network image processing also reduce communication requirements, which has been high in other existing camera networks with centralized processing. Furthermore, the mote easily integrates with other low-bandwidth sensor networks via the IEEE 802.15.4 protocol. To justify the utility of CITRIC, we present several representative applications. In particular, concrete research results will be demonstrated in two areas, namely, distributed coverage hole identification and distributed object recognition.
On mobile sensor assisted field coverage
Authors: Wang Dan , Liu Jiangchuan , Zhang Qian
Published: April 2013

Providing field coverage is a key task in many sensor network applications. With unevenly distributed static sensors, quality coverage with acceptable network lifetime is often difficult to achieve. Fortunately, recent advances on embedded and robotic systems make mobile sensors possible, and we suggest that a small set of mobile sensors can be leveraged toward a cost-effective solution for field coverage. There are, however, a series of fundamental questions to be answered in such a hybrid network of static and mobile sensors: (1) Given the expected coverage quality and system lifetime, how many mobile sensors should be deployed? (2) What are the necessary coverage contributions from each type of sensors? (3) What working and moving patterns should the sensors adopt to achieve the desired coverage contributions?

In this article, we offer an analytical study on these problems, and the results lead to a practical system design. Specifically, we present an optimal algorithm for calculating the contributions from different types of sensors, which fully exploits the potentials of the mobile sensors and maximizes the network lifetime. We then present a random walk model for the mobile sensors. The model is distributed with very low control overhead. Its parameters can be fine-tuned to match the moving capability of different mobile sensors and the demands from a broad spectrum of applications. A node collaboration scheme is then introduced to further enhance the system performance.

We demonstrate through analysis and simulation that, in our mobile assisted design, a small set of mobile sensors can effectively address the uneven distribution of the static sensors and significantly improve the coverage quality.
SenseCode
Authors: Keller Lorenzo , Atsan Emre , Argyraki Katerina , Fragouli Christina
Published: April 2013

Designing a communication protocol for sensor networks often involves obtaining the right trade-off between energy efficiency and end-to-end packet error rate. In this article, we show that network coding provides a means to elegantly balance these two goals. We present the design and implementation of SenseCode, a collection protocol for sensor networks—and, to the best of our knowledge, the first such implemented protocol to employ network coding. SenseCode provides a way to gracefully introduce a configurable amount of redundant information into the network, thereby decreasing end-to-end packet error rate in the face of packet loss. We compare SenseCode to the best (to our knowledge) existing alternative and show that it reduces end-to-end packet error rate in highly dynamic environments, while consuming a comparable amount of network resources. We have implemented SenseCode as a TinyOS module and evaluate it through extensive TOSSIM simulations.
Business Process Model Merging
Authors: La Rosa Marcello , Dumas Marlon , Uba Reina , Dijkman Remco
Published: April 2013

This article addresses the problem of constructing consolidated business process models out of collections of process models that share common fragments. The article considers the construction of unions of multiple models (called
merged models
) as well as intersections (called
digests
). Merged models are intended for analysts who wish to create a model that subsumes a collection of process models -- typically representing variants of the same underlying process -- with the aim of replacing the variants with the merged model. Digests, on the other hand, are intended for analysts who wish to identify the most recurring fragments across a collection of process models, so that they can focus their efforts on optimizing these fragments. The article presents an algorithm for computing merged models and an algorithm for extracting digests from a merged model. The merging and digest extraction algorithms have been implemented and tested against collections of process models taken from multiple application domains. The tests show that the merging algorithm produces compact models and scales up to process models containing hundreds of nodes. Furthermore, a case study conducted in a large insurance company has demonstrated the usefulness of the merging and digest extraction operators in a practical setting.
Personalized Reliability Prediction of Web Services
Authors: Zheng Zibin , Lyu Michael R.
Published: April 2013

Service Oriented Architecture (SOA) is a business-centric IT architectural approach for building distributed systems. Reliability of service-oriented systems heavily depends on the remote Web services as well as the unpredictable Internet connections. Designing efficient and effective reliability prediction approaches of Web services has become an important research issue. In this article, we propose two personalized reliability prediction approaches of Web services, that is, neighborhood-based approach and model-based approach. The neighborhood-based approach employs past failure data of similar neighbors (either service users or Web services) to predict the Web service reliability. On the other hand, the model-based approach fits a factor model based on the available Web service failure data and use this factor model to make further reliability prediction. Extensive experiments are conducted with our real-world Web service datasets, which include about 23 millions invocation results on more than 3,000 real-world Web services. The experimental results show that our proposed reliability prediction approaches obtain better reliability prediction accuracy than other competing approaches.
Verification across Intellectual Property Boundaries
Authors: Chaki Sagar , Schallhart Christian , Veith Helmut
Published: April 2013

In many industries, the importance of software components provided by third-party suppliers is steadily increasing. As the suppliers seek to secure their intellectual property (IP) rights, the customer usually has no direct access to the suppliers’ source code, and is able to enforce the use of verification tools only by legal requirements. In turn, the supplier has no means to convince the customer about successful verification without revealing the source code. This article presents an approach to resolve the conflict between the IP interests of the supplier and the quality interests of the customer. We introduce a protocol in which a dedicated server (called the “amanat”) is controlled by both parties: the customer controls the verification task performed by the amanat, while the supplier controls the communication channels of the amanat to ensure that the amanat does not leak information about the source code. We argue that the protocol is both practically useful and mathematically sound. As the protocol is based on well-known (and relatively lightweight) cryptographic primitives, it allows a straightforward implementation on top of existing verification tool chains. To substantiate our security claims, we establish the correctness of the protocol by cryptographic reduction proofs.
An Information Foraging Theory Perspective on Tools for Debugging, Refactoring, and Reuse Tasks
Authors: Fleming Scott D. , Scaffidi Chris , Piorkowski David , Burnett Margaret , Bellamy Rachel , Lawrance Joseph , Kwan Irwin
Published: April 2013

Theories of human behavior are an important but largely untapped resource for software engineering research. They facilitate understanding of human developers’ needs and activities, and thus can serve as a valuable resource to researchers designing software engineering tools. Furthermore, theories abstract beyond specific methods and tools to fundamental principles that can be applied to new situations. Toward filling this gap, we investigate the applicability and utility of Information Foraging Theory (IFT) for understanding information-intensive software engineering tasks, drawing upon literature in three areas: debugging, refactoring, and reuse. In particular, we focus on software engineering tools that aim to support information-intensive activities, that is, activities in which developers spend time seeking information. Regarding applicability, we consider whether and how the mathematical equations within IFT can be used to explain why certain existing tools have proven empirically successful at helping software engineers. Regarding utility, we applied an IFT perspective to identify recurring
design patterns
in these successful tools, and consider what opportunities for future research are revealed by our IFT perspective.
Domain-Independent Entity Coreference for Linking Ontology Instances
Authors: Song Dezhao , Heflin Jeff
Published: April 2013

The objective of entity coreference is to determine if different mentions (e.g., person names, place names, database records, ontology instances, etc.) refer to the same real word object. Entity coreference algorithms can be used to detect duplicate database records and to determine if two Semantic Web instances represent the same underlying real word entity. The key issues in developing an entity coreference algorithm include how to locate context information and how to utilize the context appropriately. In this article, we present a novel entity coreference algorithm for ontology instances. For scalability reasons, we select a neighborhood of each instance from an RDF graph. To determine the similarity between two instances, our algorithm computes the similarity between comparable property values in the neighborhood graphs. The similarity of distinct URIs and blank nodes is computed by comparing their outgoing links. In an attempt to reduce the impact of distant nodes on the final similarity measure, we explore a distance-based discounting approach. To provide the best possible domain-independent matches, we propose an approach to compute the discriminability of triples in order to assign weights to the context information. We evaluated our algorithm using different instance categories from five datasets. Our experiments show that the best results are achieved by including both our discounting and triple discrimination approaches.
Indeterministic Handling of Uncertain Decisions in Deduplication
Authors: Panse Fabian , van Keulen Maurice , Ritter Norbert
Published: April 2013

In current research and practice, deduplication is usually considered as a deterministic approach in which database tuples are either declared to be duplicates or not. In ambiguous situations, however, it is often not completely clear-cut, which tuples represent the same real-world entity. In deterministic approaches, many realistic possibilities may be ignored, which in turn can lead to false decisions. In this article, we present an indeterministic approach for deduplication by using a probabilistic target model including techniques for proper probabilistic interpretation of similarity matching results. Thus, instead of deciding for one of the most likely situations, all realistic situations are modeled in the resultant data. This approach minimizes the negative impact of false decisions. Moreover, the deduplication process becomes almost fully automatic and human effort can be largely reduced. To increase applicability, we introduce several semi-indeterministic methods that heuristically reduce the set of indeterministically handled decisions in several meaningful ways. We also describe a full-indeterministic method for theoretical and presentational reasons.
Constitutive and regulative specifications of commitment protocols
Authors: Baldoni Matteo , Baroglio Cristina , Marengo Elisa , Patti Viviana
Published: April 2013

Interaction protocols play a fundamental role in multiagent systems. In this work, after analyzing the trends that are emerging not only from research on multiagent interaction protocols but also from neighboring fields, like research on workflows and business processes, we propose a novel definition of commitment-based interaction protocols, that is characterized by the decoupling of the
constitutive
and the
regulative
specifications and that explicitly foresees a representation of the latter based on constraints among commitments. A clear distinction between the two representations has many advantages, mainly residing in a greater openness of multiagent systems, and an easier reuse of protocols and of action definitions. A language, named 2CL, for writing regulative specifications is also given together with a designer-oriented graphical notation.
Stereotypical trust and bias in dynamic multiagent systems
Authors: Burnett Chris , Norman Timothy J. , Sycara Katia
Published: April 2013

Large-scale multiagent systems have the potential to be highly dynamic. Trust and reputation are crucial concepts in these environments, as it may be necessary for agents to rely on their peers to perform as expected, and learn to avoid untrustworthy partners. However, aspects of highly dynamic systems introduce issues which make the formation of trust relationships difficult. For example, they may be short-lived, precluding agents from gaining the necessary experiences to make an accurate trust evaluation. This article describes a new approach, inspired by theories of human organizational behavior, whereby agents generalize their experiences with previously encountered partners as
stereotypes
, based on the observable
features
of those partners and their behaviors. Subsequently, these stereotypes are applied when evaluating new and unknown partners. Furthermore, these stereotypical opinions can be communicated within the society, resulting in the notion of
stereotypical reputation
. We show how this approach can complement existing state-of-the-art trust models, and enhance the confidence in the evaluations that can be made about trustees when direct and reputational information is lacking or limited. Furthermore, we show how a stereotyping approach can help agents detect unwanted biases in the reputational opinions they receive from others in the society.
Intelligent systems and technology for integrative and predictive medicine
Authors: Wang Fei-Yue , Wong Pak Kin
Published: April 2013

One of the principal goals in medicine is to determine and implement the best treatment for patients through fastidious estimation of the effects and benefits of therapeutic procedures. The inherent complexities of physiological and pathological networks that span across orders of magnitude in time and length scales, however, represent fundamental hurdles in determining effective treatments for patients. Here we argue for a new approach, called the ACP-based approach, that combines
artificial (societies), computational (experiments), and parallel (execution)
methods in intelligent systems and technology for integrative and predictive medicine, or more generally, precision medicine and smart health management. The advent of artificial societies that collect the clinically relevant information in prognostics and therapeutics provides a promising platform for organizing and experimenting complex physiological systems toward integrative medicine. The ability of computational experiments to analyze distinct, interactive systems such as the host mechanisms, pathological pathways, and therapeutic strategies, as well as other factors using the artificial systems, will enable control and management through parallel execution of real and arficial systems concurrently within the integrative medicine context. The development of this framework in integrative medicine, fueled by close collaborations between physicians, engineers, and scientists, will result in preventive and predictive practices of a personal, proactive, and precise nature, including rational combinatorial treatments, adaptive therapeutics, and patient-oriented disease management.
A fully online and unsupervised system for large and high-density area surveillance
Authors: Song Xuan , Shao Xiaowei , Zhang Quanshi , Shibasaki Ryosuke , Zhao Huijing , Cui Jinshi , Zha Hongbin
Published: April 2013

For reasons of public security, an intelligent surveillance system that can cover a large, crowded public area has become an urgent need. In this article, we propose a novel laser-based system that can simultaneously perform tracking, semantic scene learning, and abnormality detection in a fully online and unsupervised way. Furthermore, these three tasks cooperate with each other in one framework to improve their respective performances. The proposed system has the following key advantages over previous ones: (1) It can cover quite a large area (more than 60×35m), and simultaneously perform robust tracking, semantic scene learning, and abnormality detection in a high-density situation. (2) The overall system can vary with time, incrementally learn the structure of the scene, and perform fully online abnormal activity detection and tracking. This feature makes our system suitable for real-time applications. (3) The surveillance tasks are carried out in a fully unsupervised manner, so that there is no need for manual labeling and the construction of huge training datasets. We successfully apply the proposed system to the JR subway station in Tokyo, and demonstrate that it can cover an area of 60×35m, robustly track more than 150 targets at the same time, and simultaneously perform online semantic scene learning and abnormality detection with no human intervention.
A conformant planner based on approximation
Authors: Tran Vien , Nguyen Khoi , Son Tran Cao , Pontelli Enrico
Published: April 2013

This article describes the planner C
p
A(
H
), the recipient of the
Best Nonobservable Nondeterministic Planner Award
in the “Uncertainty Track” of the 6

th

International Planning Competition (IPC), 2008. The article presents the various techniques that help C
p
A(
H
) to achieve the level of performance and scalability exhibited in the competition. The article also presents experimental results comparing C
p
A(
H
) with state-of-the-art conformant planners.
A flexible approach for abstracting and personalizing large business process models
Authors: Kolb Jens , Reichert Manfred
Published: April 2013

In process-aware information systems (PAISs), usually, different user groups have distinguished perspectives on the business processes supported and on related business data. Hence, personalized views and proper abstractions on these business processes are needed. However, existing PAISs do not provide adequate mechanisms for creating and visualizing process views and process model abstractions. Usually, process models are displayed to users in exactly the same way as originally modeled. This paper presents a flexible approach for creating personalized views based on parameterizable operations. Respective view creation operations can be flexibly composed to either hide non-relevant process information or to abstract it. Depending on the parameterization of the selected view creation operations, one obtains process views with more or less relaxed properties, e.g., regarding the degree of information loss or the soundness of the resulting model abstractions. Altogether, the realized view concept allows for a more flexible abstraction and visualization of large business process models satisfying the needs of different user groups.
Fairness scheduler for virtual machines on heterogonous multi-core platforms
Authors: Shih Chi-Sheng , Wei Jie-Wen , Hung Shih-Hao , Chen Joen , Chang Norman
Published: April 2013

Heterogeneous multi-core processors are now widely deployed to meet computation requirements for multimedia applications on embedded mobile devices. However, due to the difference on computation capability of heterogeneous multi-cores, it is challenging to share the load among cores and to better utilize the cores on the processor. In this work, we develop a fairness scheduler to share the load among cores to meet the above challenge. The developed framework ensures that each virtual machine receives its proportional share of computation time over different processing elements. To fairly schedule the tasks on the platform, VM-aware fair scheduler (VMAFS) takes into account the preemptibility of processes on co-processors. A family of algorithms is designed to schedule tasks on preemptive and non-preemptive processing elements. We define fairness on such architectures and use this metric to efficiently drive VMAFS algorithm so as to fairly manage non-preemptive computing resources. Performance evaluations result show that when VMAFS algorithm is used, scheduling fairness is not sensitive to the amount of computation time of non-preemptive tasks. In addition, VMAFS algorithm greatly outperforms credit-based scheduling algorithm, which is deployed in existing virtualization environment.
Robust and flexible tunnel management for secure private cloud
Authors: Lu Yung-Feng , Kuo Chin-Fu
Published: April 2013

Private cloud is cloud infrastructure operated solely for a single organization, whether managed internally or by a third-party and hosted internally or externally. It provides a flexible way to extend the working environment. Since the business process that working on them could be critical, it is important to provide a secure environment for organizations to execute those processes. While user mobility has become an important feature for many systems, technologies that provide users a lower cost and flexible way in joining a secure private cloud are in a strong demand. This paper exploits the key management mechanisms to have secured tunnels with private cloud for users who might move around dynamically without carrying the same machine. A strong authentication with a key agreement scheme is proposed to establish the secure tunnel. Furthermore, the proposed framework also provides mutual authentication, session key renewal between the users and the cloud server. Several related security properties of the proposed mechanism are also presented.
An on-line hot data identification for flash-based storage using sampling mechanism
Authors: Park Dongchul , Nam Young Jin , Debnath Biplob , Du David H. C. , Kim Youngkyun , Kim Youngchul
Published: April 2013

Efficient hot and cold data identification in computer systems has been a fundamental issue. However, it has been least investigated. In this paper, we propose a novel on-line hot data identification scheme for flash-based storage named HotDataTrap. The main idea is to maintain a working set of potential hot data items in a cache based on a sampling mechanism. This sampling-based scheme enables HotDataTrap to early discard some of the cold items so that it can reduce runtime overheads as well as a waste of memory spaces. Moreover, our two-level hash indexing scheme helps HotDataTrap directly look up a requested item in the cache and save a memory space further by exploiting spatial localities. Both our sampling approach and hierarchical hash indexing scheme empower HotDataTrap to precisely and efficiently identify hot data with a even less memory. Our extensive experiments with various realistic workloads demonstrate that our HotDataTrap outperforms the state-of-the-art scheme by an average of 335% and our two-level hash indexing scheme considerably improves further HotDataTrap performance up to 50.8%.