Miracle-dz/UniFAR-FTUs huggingface dataset:
Square-Rooting Algorithms for High-Speed Digital Circuits

Two binary algorithms for the square rooting of a number or of a sum of two numbers are presented. They are based on the classical nonrestoring method. The main difference lies in the replacement of subtractions and additions by a parallel reduction f three summands, which may be positive and negative, to two summands to eliminate the carry propagation. Two of three summands form the successive partial remainder. Their most significant bit triples, sometimes together with a sign bit of the earlier partial remainder, are used to determine digits -1,0, +1 of a redundant square-root notation. These digits are transformed during the square-rooting process into the conventional notation square-root bits which are next used in further square-rooting steps to form the third reduced summands.
Detection of TeV Gamma-Rays from the BL Lac 1ES 1959+650 in its low states and during a major outburst in 2002 ⋆

TeV γ-rays from the BL Lac object 1ES 1959+650 have been measured during the years 2000 and 2001 with a significance of 5.2 σ at a value of 5.3% of the Crab flux and in May 2002 during strong outbursts with >23 σ at a flux level of up to 2.2 Crab, making 1ES 1959+650 the TeV Blazar with the third best event statistics. The deep observation of 197.4 h has been performed with the HEGRA stereoscopic system of 5 imaging atmospheric Cherenkov telescopes (IACT system). 1ES 1959+650 is located at a redshift of z = 0.047, providing an intermediate distance between the nearby Blazars Mkn 421 and Mkn 501, and the much more distant object H1426+428. This makes 1ES 1959+650 an important member of the class of TeV Blazars in view of the absorption of TeV photons by the diffuse extragalactic background radiation (DEBRA). The differential energy spectrum of 1ES 1959+650 during the flares can be fitted by a power law with a spectral index of 2.83 ± 0.14stat ± 0.08sys or by a power law with an exponential cut-off at (4.2 +0.8 −0.6 stat ± 0.9sys) TeV and a spectral index of 1.83 ± 0.15stat ± 0.08sys. The low state differential energy spectrum obtained with lower statistics can be described by a pure power law with a spectral index of 3.18 ± 0.17stat ± 0.08sys.
Flow-centric Visibility Tools for OF@TEIN OpenFlow-based SDN Testbed

One key challenge in operating virtualized Future Internet testbed is how to monitor various experiments running on the top of it. Among multiple visibility levels for resources, flows, and services, flow-centric visibility is becoming crucial. In this paper, in order to monitor lifecycle experiments over OF@TEIN OpenFlow-based SDN testbed, we are working on flow-centric visibility. The main idea behind flow-centric visibility is duplicating specific packets from OpenFlow-enabled switches and redirecting those packets via a visibility fabric. The duplicated and redirected packets are processed to provide basic visualization about flow information. The flow tapping, implemented for the virtual switches of OF@TEIN SmartX Boxes, is preliminary verified by utilizing it to monitor the targeted lifecycle experiments.
Structure learning of antiferromagnetic Ising models

In this paper we investigate the computational complexity of learning the graph structure underlying a discrete undirected graphical model from i.i. d. samples. Our first result is an unconditional computational lower bound of Ω(pd/2) for learning general graphical models on p nodes of maximum degree d, for the class of so-called statistical algorithms recently introduced by Feldman et al. [1]. The construction is related to the notoriously difficult learning parities with noise problem in computational learning theory. Our lower bound suggests that the O(pd+2) runtime required by Bresler, Mossel, and Sly's [2] exhaustive-search algorithm cannot be significantly improved without restricting the class of models. Aside from structural assumptions on the graph such as it being a tree, hypertree, tree-like, etc., many recent papers on structure learning assume that the model has the correlation decay property. Indeed, focusing on ferromagnetic Ising models, Bento and Montanari [3] showed that all known low-complexity algorithms fail to learn simple graphs when the interaction strength exceeds a number related to the correlation decay threshold. Our second set of results gives a class of repelling (antiferromagnetic) models that have the opposite behavior: very strong interaction allows efficient learning in time O(p2). We provide an algorithm whose performance interpolates between O(p2) and O(pd+2) depending on the strength of the repulsion.
The Influence of Synchrony and Sensory Modality on the Person Perception Process in Computer-Mediated Groups

This study examined the effects of synchrony and the number of cues on the person perception process in computer-mediated communication. One hundred and forty-two participants in groups of three or four engaged in collaboration over five weeks to develop oral reports, using alternate versions of communication systems or meeting face-to-face. Consistent with the hyperpersonal model, those using low cue media felt their partners were more credible, and reported more social attraction, less uncertainty, and more involvement in the interaction than those using high cue media. People interacting with synchronous media felt increased social attraction, self-reported involvement, and certainty. They also felt that their conversations were more effective, although this effect appeared mainly in low cue groups. Results of an exploratory path analysis suggest that future research should focus on causal chains rather than direct effects, and that intervening variables (such as involvement) may be central to our understanding of the effects of communication technology systems.
Desensitization of the actin polymerization response in human neutrophils at low cell density

Many chemoattractant‐activated responses in neutrophils show transient kinetics, suggesting that rapid desensitization occurs during the time course of the response. We found that desensitization of the actin polymerization response to N‐formyl peptides is, in a large part, due to inhibition by adenosine released from cells to the medium and depletion or a chemical inactivation of the agonist. To reduce the influence of these factors, we stimulated neutrophils in a very diluted suspension, sometimes with continuous replacement of the medium. The actin polymerization response to a high agonist concentration was greatly enhanced and prolonged under these conditions, often without any tendency to subside within 10 min at 25°C. It has previously been shown that the N‐formyl peptide receptor converts from a rapidly dissociating to a slowly dissociating and presumably inactive form during activation. Under the conditions of low cell concentration, the conversion to a slowly dissociating receptor still occurred. Thus the prolonged response was not due to prolonged presence of rapidly dissociating receptors. We conclude either that a low number of rapidly dissociating receptors, which we failed to see, is sufficient to maintain actin polymerization or that slowly dissociating receptors can support the actin response. In contrast to responses stimulated by high agonist concentrations, the responses to low concentrations of the agonists were transient. The results of other authors indicate that low concentrations of N‐formyl peptides do not desensitize the receptors. Other mechanisms, which are specific for the actin polymerization response, must be involved in response termination to low concentrations of N‐formyl peptides. Activation at low cell density will be a useful approach for studying other processes (Ca2+ elevation, oxidant production, etc.) and chemoattractants (leukotriene B4, interleukin 8, etc.) for which an understanding of the kinetics due to desensitization of the components of the receptor‐mediated activation pathway is desired.
Linking e-mails and source code artifacts

E-mails concerning the development issues of a system constitute an important source of information about high-level design decisions, low-level implementation concerns, and the social structure of developers. Establishing links between e-mails and the software artifacts they discuss is a non-trivial problem, due to the inherently informal nature of human communication. Different approaches can be brought into play to tackle this trace-ability issue, but the question of how they can be evaluated remains unaddressed, as there is no recognized benchmark against which they can be compared. In this article we present such a benchmark, which we created through the manual inspection of a statistically significant number of e-mails pertaining to six unrelated software systems. We then use our benchmark to measure the effectiveness of a number of approaches, ranging from lightweight approaches based on regular expressions to full-fledged information retrieval approaches.
Prevalence of Psychiatric Disorders Among Unaccompanied Asylum-Seeking Adolescents in Norway

Unaccompanied asylum-seeking children (UASC) are known to be subjected to several potentially traumatic life events, risking more mental health problems than other populations of same age. In this study, we aimed to explore the prevalence of psychiatric morbidity at an early stage after arrival to the host country. We performed structured clinical interviews (CIDI) with 160 male UASC from different countries (Afghanistan, Somalia, Iran), after four months in Norway. Most of the participants had experienced life threatening events (82%), physical abuse (78%), or loss of a close relative (78%) in their former life. Altogether 41.9% of the participants fulfilled diagnostic criteria for a current psychiatric disorder. The most prevalent diagnosis was PTSD (30, 6%), followed by MDD (9, 4%), Agoraphobia (4, 4%) and GAD (3, 8%). Implications of this vulnerability call for more mental health resources in the early stages of the asylum process. Increased awareness of psychiatric morbidity in UASC may improve the prognosis, give more appropriate care, and ease the integration process on all levels of society.
Automated GUI Testing of Android Apps: From Research to Practice

The last decade has seen tremendous proliferation of mobile computing in our society. Billions of users have access to millions of mobile apps that can be installed directly on their mobile devices, electrical appliances, and watches. Factors such as new monetization/revenue models, programming models, and distribution infrastructures contribute to an "attractive" movement that captivates new and traditional developers, as well as a crowd of other professionals that explore, design, and implement mobile apps. Also, the need for "enterprise apps" that support start-ups or serve as a new front-end for traditional companies is pushing software-related professionals to embrace mobile technologies. However, the nature of the economy (devices, apps, markets) imposes new challenges on how mobile apps are envisioned, designed, implemented, tested, released, and maintained. This technology briefing aims to help address the challenges of testing and maintaining mobile apps by providing participants from both academic and industrial backgrounds with information on the state-of-art and state-of-practice mobile testing techniques. Specifically, we aim to (i) highlight new techniques and methodologies for making effective automated testing of mobile apps practical and accessible to developers, and (ii) discuss open academic research questions related to such technology transfer.
Effect of static compression on proteoglycan biosynthesis by chondrocytes transplanted to articular cartilage in vitro

Transplantation of chondrocytes by injection or within carrier matrices has shown promise for augmenting the repair of articular cartilage defects. In vivo, transplanted chondrocytes are exposed to mechanical forces. This in vitro study examined the effect of a step application of compressive load to chondrocytes after the cells had been seeded onto a cartilage surface. Bovine chondrocytes were transplanted onto bovine cartilage disks, allowed to attach for 1 hour or 4 days, and subjected to compression through overlying cartilage disks in a confined compression configuration. Before use, the disks were lyophilized to lyse the endogenous chondrocytes and thereby allow assessment of the metabolic activity of the transplanted cells. During a 16‐hour application of compressive stress of 0‐24‐0.72 MPa, proteoglycan synthesis, assessed as [35S]sulfate incorporation into macromolecules. was inhibited by approximately 68% after the 1‐hour attachment and by approximately 45% after the 4‐day attachment. Cell retention after the application of load was assessed by use of [3H]thymidine‐tagged chondrocytes and quantitation of the displacement of radioactivity. After the 1‐hour seeding period, loading induced a dose‐dependent dislodgment of [3H]radioactivity (as much as 35%) from the tissue bilayer. In contrast, after the 4‐day seeding period, there was no detectable effect of loading on chondrocyte dislodgment with an 8–12% release of radioactivity. The inhibitory effect of a 16‐hour compression of 0.48 MPa applied after the 4‐day seeding period was studied further. This protocol did not appear to have an irreversible effect on chondrocyte metabolism; at 2 days after the release of load, proteoglycan synthesis by the loaded cells was stimulated by 41% compared with transplanted cells that were not subjected to loading. These results suggest that the application of static compressive stress to chondrocytes at a cartilage surface may affect biosynthesis by these cells and thus subsequent integrative cartilage repair. Such an effect may have implications for optimization of the tightness of the press fit of a cell‐laden cartilaginous construct into an articular defect.
Traffic Analysis with Off-the-Shelf Hardware: Challenges and Lessons Learned

In recent years, the progress in both hardware and software allows user-space applications to capture packets at 10 Gb/s line rate or more, with cheap COTS hardware. However, processing packets at such rates with software is still far from being trivial. In the literature, this challenge has been extensively studied for network intrusion detection systems, where per-packet operations are easy to parallelize with support of hardware acceleration. Conversely, the scalability of statistical traffic analyzers (STAs) is intrinsically complicated by the need to track per-flow state to collect statistics. This challenge has received less attention so far, and it is the focus of this work. We present and discuss design choices to enable a STA to collects hundreds of per-flow metrics at a multi-10-Gb/s line rate. We leverage a handful of hardware advancements proposed over the last years (e.g., RSS queues, NUMA architecture), and we provide insights on the trade-offs they imply when combined with state-of-the-art packet capture libraries and the multi-process paradigm. We outline the principles to design an optimized STA, and we implement them to engineer DPDKStat, a solution combining the Intel DPDK framework with the traffic analyzer Tstat. Using traces collected from real networks, we demonstrate that DPDKStat achieves 40 Gb/s of aggregated rate with a single COTS PC.
Growth kinetics of titanium boride layers on the surface of Ti6Al4V

Growth kinetics of titanium boride layers on the surface of Ti6Al4V Fenghua LI 1)∗, Xiaohong YI , Jinglei ZHANG , Zhanguo FAN , Dianting GONG 2) and Zhengping XI 3) 1) School of Material & Metallurgy, Northeastern University, Shenyang 110819, China 2) Vocational Technology College, Liaoning Shihua University, Fushun 113001, China 3) Northwest Institute for Non-ferrous Metal Research, Xi′an 710016, China Manuscript received 31 December 2009; in revised form 1 April 2010
Tailwinds and Headwinds: How Does Growth in the BRICs Affect Inflation in the G7?

In this paper, we analyse the impact of a persistent productivity increase in a set of countries – which we think of as the BRIC economies – on inflation in their trading partners, the G7. In particular we want to understand conditions under which this shock can lead to tailwinds or headwinds in the economies of trading partners. We build a three-country DSGE model in which there are two oil-importing countries (home and foreign) and one oil-exporting country. We perform several experiments where we try to disentangle the importance of different factors that can shape inflation dynamics in the home country when the foreign country is hit by a persistent productivity shock. These factors are wage stickiness, the role of the oil sector and its share in both consumption and production, foreign monetary policy and the degree of completeness of financial markets. We find that the tailwinds effect, lowering inflation in the home economy, dominates the headwinds effect as long as there is scope for borrowing and lending across countries and the foreign country’s production is not too oil intensive.
Dissociation of rugose‐dependent short‐term memory component from memory consolidation in Drosophila

Extensive investigations show several molecular and neuroanatomical mechanisms underlying short‐lived and long‐lasting memory in Drosophila. At the molecular level, the genetic pathway of memory formation, which was obtained through mutant research, seems to occur sequentially. So far, studies of Drosophila mutants appear to support the idea that mutants defective in short‐term memory (STM) are always associated with long‐term memory (LTM) impairment. At the neuroanatomical level, distinct memory traces are partially independently distributed. However, whether memory phase dissociation also exists at the molecular level remains unclear. Here, we report on molecular separation of STM and consolidated memory through genetic dissection of rugose mutants. Mutants in the rugose gene, which encodes an evolutionarily conserved A‐kinase anchor protein, show immediate memory defects as assayed through aversive olfactory conditioning. Intriguingly, two well‐defined consolidated memory components, anesthesia‐resistant memory and protein synthesis‐dependent LTM, are both normal in spite of the defective immediate memory after 10‐session massed and spaced training. Moreover, rugose genetically interacts with cyclic AMP‐protein kinase A signaling during STM formation. Considering our previous study that AKAP Yu specifically participates in LTM formation, these results suggest that there exists a molecular level of memory phase dissociation with distinct AKAPs in Drosophila.
Kernel Mechanisms for Service Differentiation in Overloaded Web Servers

The increasing number of Internet users and innovativenew services such as e-commerce are placing new demands on Web servers. It is becoming essential for Web servers to provide performance isolation, have fast recovery times, and provide continuous service during overload at least to preferred customers. In this paper, we present the design and implementation of a kernel-based architecture that protects Web servers against overload by controlling the amount and rate of work entering the system. We present three mechanisms that provide admission control and service differentiation based on connection and application level information. Our basic admission control mechanism, TCP SYN policing, limits the acceptance rate of new requests based on the connection attributes. The second mechanism,prioritized listen queue, supports different service classes by reordering the listen queue of a server socket based on the priorities of the incoming connection requests. Third, we present URL-based connection control that uses application-level information such as URLs and cookies to define priorities and rate control policies. We have implemented these mechanisms in AIX 5.0. Through numerous experiments we demonstrate the effectiveness of these mechanisms in achieving the desired degree of service differentiation during overload. We also show that the kernel mechanisms are more efficient and scalable than application level controls implemented in the Web server.
Diagnosing Memory Provisioning in IaaS Clouds

Infrastructure-as-a-service (IaaS) clouds enable customers to allocate computing resources in a flexible manner to satisfy their needs, and pay only for the allocated resources. One of the challenges for IaaS customers is the correct provisioning of their resources. Many users end up under provisioning, hurting application performance, or over provisioning, paying for resources that are not really necessary. Memory is an essential resource for any computing system, and is frequently a performance-limiting factor in cloud environments. Our work uses monitoring to enable a cloud customer to determine if the memory allocated to his virtual machines is correctly provisioned, under provisioned, or over provisioned. Experimental results with the Xen platform demonstrate the effectiveness of the proposed approach.
A query suggestion method based on random walk and topic concepts

Related query suggestion is very important for search engines. Users could find required information more quickly and accurately with the help of query suggestions, which could greatly improve users' search experience. Thus, query suggestion technology has become a research hotspot in the field of the search engine. Most of existing methods focused on the query log data to mine related queries. However, some of the query log data exist relatively sparse characteristics and have some interferential noise data. Besides, the method that only focus on query log trend to fail to consider the user's initial query intention. These shortages would reduce the accuracy of the recommendation. Thus, this paper proposes a query suggestion method based on random walk and topic concepts (QuS-RWTC). The method is based on the query log data and suggestions from other mature search engines, which could make the suggestions more comprehensive and obtain a higher coverage. In addition, the paper further executes procedures of topic concepts to re-order the candidate queries, which make the suggestions more accurate, since they are more satisfied to the user's initial intention. The results prove the excellent performance of QuS-RWTC method compared with traditional methods and validate the importance of topic concepts.