Miracle-dz/UniFAR-FTUs huggingface dataset:
The Impact of Directional Antennas on MAC Layer Protocol for Ad-Hoc Networks

The application of directional antennas in the mobile devices of wireless ad hoc networks has the potential to increase the network connectivity and capacity. Previous research in ad hoc networks typically assumes the use of omnidirectional antennas at all nodes. With omnidirectional antennas, while two nodes are communicating using a given channel, MAC protocols such as IEEE 802.11 require all other nodes in the vicinity to remain silent. With directional antennas, two pairs of nodes located in each other’s vicinity may potentially communicate simultaneously, increasing spatial reuse of the wireless channel. Range extension due to higher gain of directional antennas can also be useful in discovering fewer hop routes. Directional antennas provide numerous benefits, such as higher gains, increased transmission range and low interferences at all nodes. However, new problems arise when using directional beams, that simple modifications to 802.11 may not be able to mitigate. This paper identifies these problems and mention the possible modification to MAC protocol for directional antennas.
Developing and implementing new safe practices: voluntary adoption through statewide collaboratives

Background: Disseminating new safe practices has proved challenging. In a statewide initiative we developed a framework for (1) selecting two safe practices, (2) developing operational details of implementation, (3) enlisting hospitals to participate, and (4) facilitating implementation. Methods: Potential topics were selected by a multistep process to identify candidate practices, review the evidence for efficacy and feasibility, and then select them on the basis of importance, efficacy, feasibility, and impact. A multi-stakeholder advisory group representing all constituencies selected two practices: reconciling medications (RM) and communicating critical test results (CTR). Operational details and strategies for implementation were then developed for each practice using a consensus process of discipline stakeholders led by content experts. Hospital CEOs were solicited to participate by the Massachusetts Hospital Association which made the project a “flagship” initiative. A collaborative model was used to facilitate implementation, following the IHI Model for Improvement. In addition to providing exposure to content and method experts, we gave teams a “toolkit” containing recommendations, a change package, and implementation strategies. Each collaborative met four times over an 18 month period. Results were assessed using the IHI team assessment scale and surveys of teams and hospital leaders. Results: Hospital participation rate was high with 88% of hospitals participating in one or both collaboratives. Partial implementation of the practices was achieved by 50% of RM teams and 65% of CTR teams. Full implementation was achieved by 20% of teams for each. Conclusions: Major factors leading to hospital participation included the intrinsic appeal of the practices, access to experts, and the availability of implementation strategies. Team success was correlated with active engagement of a senior administrator, engagement of physicians, increased use of PDSA cycles, and attendance at collaborative meetings. The prior development of subpractices, recommendations and implementation strategies was essential for the hospital teams. These should be well worked out before hospitals are required to implement any guideline.
Reversed items in Likert scales: Filtering out invalid responders

Likert type scales are commonly used in social sciences. Most of the Likert scales include both positivelyand negatively worded items. However, the use of negatively worded (reversed) items is supported by some researchers but not others. This study analyzes the reversed items in educational settings. The school age, self-rating version of the Dimensions of Mastery Questionnaire (DMQ 17) was used. The sample consisted of 7261 Hungarian students, age 10 to 16. An iteration method was developed and used to filter our presumably invalid responders. The analysis is based on the empirical inconsistency between the reversed and the positively worded items. The iteration eliminated step-by-step the possibly invalid questionnaires. The reliabilities of the scales were increased with the iteration process. After eliminating about 20% of the sample, the reliabilities were somewhat higher with all scales having acceptable alphas. If one would like to use this iteration method for eliminating the invalid responders, he or she needs to oversample the accessible population. Based on this results we eliminated the reversed items form the new DMQ persistence and pleasure scales.
And the Last Shall Be First: Heterochrony and Compensatory Marine Growth in Sea Trout (Salmo trutta)

Early juvenile growth is a good indicator of growth later in life in many species because larger than average juveniles tend to have a competitive advantage. However, for migratory species the relationship between juvenile and adult growth remains obscure. We used scale analysis to reconstruct growth trajectories of migratory sea trout (Salmo trutta) from six neighbouring populations, and compared the size individuals attained in freshwater (before migration) with their subsequent growth at sea (after migration). We also calculated the coefficient of variation (CV) to examine how much body size varied across populations and life stages. Specifically, we tested the hypothesis that the CV on body size would differ between freshwater and marine environment, perhaps reflecting different trade-offs during ontogeny. Neighbouring sea trout populations differed significantly in time spent at sea and in age-adjusted size of returning adults, but not on size of seaward migration, which was surprisingly uniform and may be indicative of strong selection pressures. The CV on body size decreased significantly over time and was highest during the first 8 months of life (when juvenile mortality is highest) and lowest during the marine phase. Size attained in freshwater was negatively related to growth during the first marine growing season, suggesting the existence of compensatory growth, whereby individuals that grow poorly in freshwater are able to catch up later at sea. Analysis of 61 datasets indicates that negative or no associations between pre- and post-migratory growth are common amongst migratory salmonids. We suggest that despite a widespread selective advantage of large body size in freshwater, freshwater growth is a poor predictor of final body size amongst migratory fish because selection may favour growth heterochrony during transitions to a novel environment, and marine compensatory growth may negate any initial size advantage acquired in freshwater.
Sim-min-hash: an efficient matching technique for linking large image collections

One of the most successful method to link all similar images within a large collection is min-Hash, which is a way to significantly speed-up the comparison of images when the underlying image representation is bag-of-words. However, the quantization step of min-Hash introduces important information loss. In this paper, we propose a generalization of min-Hash, called Sim-min-Hash, to compare sets of real-valued vectors. We demonstrate the effectiveness of our approach when combined with the Hamming embedding similarity. Experiments on large-scale popular benchmarks demonstrate that Sim-min-Hash is more accurate and faster than min-Hash for similar image search. Linking a collection of one million images described by 2 billion local descriptors is done in 7 minutes on a single core machine.
Endomorphisms of B(H)

The unital endomorphisms of B(H) of (Powers) index n are classified by certain U(n)-orbits in the set of non-degenerate representations of the Cuntz algebra O_n on H. Using this, the corre- sponding conjugacy classes are identified, and a set of labels is given. This set is given as P modulo a certain non-smooth equivalence, where P is a set of pure state on the UHF algebra of Glimm type n^infinity. Several subsets of P, giving concrete examples of non- conjugate shifts, are worked out in detail, including sets of product states, and a set of nearest neighbor states.
The scrum-down on brain damage effects of cumulative mild head injury in rugby: a comparison of group mean scores between national rugby players and non-contact sport controls

The present study comprises the second phase of a larger and ongoing research study investigating the brain damage effects of cumulative mild head injury in rugby. The purpose of this study was to determine whether cumulative mild head injury sustained in the game of rugby would cause brain injury as evidenced by impaired performance on sensitive neuropsychological tests. Participants were Springbok professional rugby players (n = 26), Under 21 rugby players (n = 19), and a non-contact sport control of national hockey players (n = 21). Comparisons of performance were carried out across a spectrum of neuropsychological tests for the three rugby groups (Total Rugby, Springbok Rugby, and Under 21 Rugby) versus the performance of the non-contact sport control group (Hockey Control), as well as comparisons of performance f9r the subgroups of Rugby Forwards versus Rugby Backs. Comparisons revealed a consistent pattern of poorer performance across all rugby groups relative to the performance of the controls on tests highly sensitive to the effects of diffuse brain damage. Within rugby group comparisons (Forwards versus Backs) showed significantly poorer performance for Total Rugby Forwards and Springbok Rugby Forwards relative to the performance of the respective Total Rugby Backs and Springbok Rugby Backs \ on sensitive, as well as on somewhat less sensitive, neuropsychological tests. J The performance of Under 21 Rugby Forwards relative to Under 21 Rugby Backs demonstrated similar trends. Brain reserve capacity theory was used as a conceptual basis for discussing the implications of these findings.
Improving SDRAM access energy efficiency for low-power embedded systems

DRAM (dynamic random-access memory) energy consumption in low-power embedded systems can be very high, exceeding that of the data cache or even that of the processor. This paper presents and evaluates a scheme for reducing the energy consumption of SDRAM (synchronous DRAM) memory access by a combination of techniques that take advantage of SDRAM energy efficiencies in bank and row access. This is achieved by using small, cachelike structures in the memory controller to prefetch an additional cache block(s) on SDRAM reads and to combine block writes to the same SDRAM row. The results quantify the SDRAM energy consumption of MiBench applications and demonstrate significant savings in SDRAM energy consumption, 23%, on average, and reduction in the energy-delay product, 44%, on average. The approach also improves performance: the CPI is reduced by 26%, on average.
Decentralized estimation and control of algebraic connectivity of random ad-hoc networks

In this paper, we propose a decentralized algorithm for the estimation and control of connectivity of random ad hoc networks. First, we introduce a novel stochastic power iteration method that allows each node to estimate and track the expected algebraic connectivity of a random graph. The proposed method is then used to adapt the power transmitted by each node in order to drive the network connectivity toward a desired value. Numerical results illustrate the main features of the algorithm and its robustness to fluctuations of the network graph due to the presence of random link failures.
Optimization of Soft Handover Parameters for UMTS Network in Indoor

The aim of this paper is to present the impact of different SHO parameters on UMTS network performance in indoor environment. The measurement results of th e impact of the most important SHO parameters, i.e., the thresholds for add and drop events and their time t o trigger values are presented on UMTS indoor network performance in terms of average downlink SIR target , downlink transmit power, SHO probability, and observed BER values. Due to indoor propagation channel, which causes smaller delay spread and hence less multipat h diversity, a UMTS signal becomes inherently “narrowband”. Therefore, the gain of SHO against fast and slow fading would be crucial. Moreover, the charact eristics of indoor radio channel enforce to apply different SHO parameter settings than for outdoor network. In the frame of this paper, the analysis is based on the downlin k as it is seen more crucial from SHO point of view due to add itional link required for SHOs. The measurement results indicate that relatively large thresholds for add and drop events simultaneously with a long time to trigger for drop event are the most suitable for UMTS indoor environment due to the lack of multipath diversity, and to combat fast and deep fluctuations of the indoor radio channel.
Automatic Incrementalization of Static Analyses

Modern development environments integrate various static analyses into the build process. But, analyses that analyze the whole project whenever the project changes are impractical in this context. We present an approach to automatic incrementalization of analyses that are specified as tabled logic programs and evaluated using incremental tabled evaluation, a technique for efficiently updating memo tables in response to changes in facts and rules. The approach has been implemented and integrated into the Eclipse IDE. Our measurements show that this technique is effective for automatically incrementalizing a broad range of static analyses.
Harmonicity-Based Blind Dereverberation for Single-Channel Speech Signals

The distant acquisition of acoustic signals in an enclosed space often produces reverberant artifacts due to the room impulse response. Speech dereverberation is desirable in situations where the distant acquisition of acoustic signals is involved. These situations include hands-free speech recognition, teleconferencing, and meeting recording, to name a few. This paper proposes a processing method, named Harmonicity-based dEReverBeration (HERB), to reduce the amount of reverberation in the signal picked up by a single microphone. The method makes extensive use of harmonicity, a unique characteristic of speech, in the design of a dereverberation filter. In particular, harmonicity enhancement is proposed and demonstrated as an effective way of estimating a filter that approximates an inverse filter corresponding to the room impulse response. Two specific harmonicity enhancement techniques are presented and compared; one based on an average transfer function and the other on the minimization of a mean squared error function. Prototype HERB systems are implemented by introducing several techniques to improve the accuracy of dereverberation filter estimation, including time warping analysis. Experimental results show that the proposed methods can achieve high-quality speech dereverberation, when the reverberation time is between 0.1 and 1.0 s, in terms of reverberation energy decay curves and automatic speech recognition accuracy
MIL at ImageCLEF 2013: Personal Photo Retrieval

In this paper, we describe our methods for ImageCLEF 2013 Personal Photo Retrieval Task. We devote our attention to making our system efficient in retrieving documents which have the similar topic with few query data. We train a ranking function using rankSVM. We extract Fisher Vectors (FVs) from several local descriptors as visual features, and use Bag-of-Words (BoW) as metadata features. The final similarity score is the weighted average of the visual similarities and the metadata similarities, where the weights are determined by relevance feedback. Results have shown that our system achieves the best performance in the Personal Photo Retrieval Task.
Approximate Bayesian Computation Estimator for Respondent-Driven Sampling

Respondent-driven sampling is a network-based technique to collect information and make estimation about behavior and composition of social groups in hidden population. The non-randomly selected samples prohibit the use of the sample mean as a statistically valid estimator. Researchers have proposed several asymptotically unbiased estimators, but many fail to realize that the high variance of these estimators inevitably leads to attenuated performance. We propose to use a Bayesian estimator in the hope of achieving better precision by reducing variance of the estimator.
Traceable Technique to Calibrate Clamp Meters in AC Current From 100 to 1500 A

A measurement technique to calibrate current clamp meters in ac current in the measurement range from 100 to 1500 A at 50 Hz has been developed at the National Institute of Metrological Research (INRIM) in addition to the primary reference measurement systems for ac current calibrations at INRIM. This technique is traceable to the national standards of dc resistance, dc voltage, and ac current ratio. It is based on a standard current transformer (CT), on a 50-mΩ standard shunt, and on a 61/2-digit digital voltmeter (DVM) that measures the voltage on the standard shunt inserted in a conductor, to which also the clamp meter is applied, whose current is supplied by a CT that can generate currents up to 1500 A. The CT is controlled by a variable transformer. The clamp meter is applied to a copper wire and placed on a tilting support simulating the actual operating mode of the meter. This measurement technique is applicable in industrial metrological laboratories and is an alternative to measurement practices of accredited secondary laboratories involving digital calibrators and turn current coils. This measurement technique was also tested utilizing an 81/2-digit high-accuracy DVM. The results of the evaluation are presented and discussed. The expanded (k = 2) uncertainties of the technique span from 1.0 × 10-2 at 100 A to 2.0 ×10-3 at 1500 A.
Using Nested Surfaces to Detect Structures in Databases

We define, compute, and evaluate nested surfaces for the purpose of visual data mining. Nested surfaces enclose the data at various density levels, and make it possible to equalize the more and less pronounced structures in the data. This facilitates the detection of multiple structures, which is important for data mining where the less obvious relationships are often the most interesting ones. The experimental results illustrate that surfaces are fairly robust with respect to the number of observations, easy to perceive, and intuitive to interpret. We give a topology-based definition of nested surfaces and establish a relationship to the density of the data. Several algorithms are given that compute surface grids and surface contours, respectively.
A QoS aware Routing Protocol in Wireless Sensor Networks with Mobile Base Stations

Wireless Sensor Networks (WSNs) are deployed in different applications such as environmental monitoring, surveillance, healthcare, habitat monitoring, industrial monitoring etc. for monitoring, gathering and sending data to a control station called sink or base station. It is an emerging area of research and provision of Quality of Service (QoS) is a challenging problem in many such applications mentioned above. Delay is an important QoS parameter for timely delivery of event information in delay sensitive applications of wireless sensor networks. In this paper, we propose a delay aware routing protocol for wireless sensor networks with mobile base stations. We have also taken reliability into our consideration by keeping the provision of transmitting data to multiple base stations. The performance of the proposed works is evaluated by simulation using NS-2 simulator.
Residents’ impact perceptions of and attitudes towards tourism development: a meta-analysis

ABSTRACT Applying a meta-analysis approach, this study examines the applicability of SET on explaining residents’ impact perceptions of and attitudes toward tourism development. Findings confirm the applicability of SET in tourism impact studies when assessing the impacts of perceived benefits (positive impacts) on support. Findings reveal that perceived benefits produce substantial effects on support while perceived costs (negative impacts) have trivial effects, which suggest that measures and indicators used to assess residents perceptions of perceived costs (negative impacts) may have validity problems. Moreover, a closer examination of the mean effects of five exogenous determinants of impact perceptions reveal that none of those variables have significant effects on the perceptions of negative impacts further suggesting possible problems with the operationalization of negative impact perceptions. Findings clearly suggest that a closer examination of the measurement items used to assess the negative impact perceptions of tourism impacts is needed.
High Speed Power Factor Measurement by ASIC

A country's economy depends upon the power generation and consumption, so to deploy it (power) is a topic of interest and importance. Today power factor measurement devices are implemented so as to reduce the power wastage as it is one of the sources of energy. All the electrical transmission system that are designed for power transmission must have the ability to transfer the complete power to the load (destination), the system mainly emphasis on the maximum power transmission, but practically it is not achievable, because of presence of passive components (inductors, capacitors) present in the system. "Power factor" is the term that describes the measurement of power transfer.
High-efficiency logarithmic number unit design based on an improved cotransformation scheme

The logarithmic number system (LNS) has always been an interesting alternative for floating point calculations since the implementation of several arithmetic operations such as divisions, exponentiations and square-roots, which are required for computationally intensive nonlinear functions, is greatly simplified in the logarithmic space. However, additions and subtractions become nonlinear operations that have to be approximated using polynomials for area efficient realizations. A particular challenge is the accuracy within the so-called critical region which is encountered for subtractions where the difference between the operands is close to zero. In the literature, several arithmetic cotransformations that reduce the overhead of approximating these operations have been presented. Even so, the main problem with practical LNS realizations is the area overhead when compared to standard FPUs with comparable accuracy. In this paper, we propose a highly hardware-efficient novel cotransformation concept that not only reduces the area requirements by up to 35% when compared to the state-of-the-art, but also allows the LNU to calculate single cycle logarithms and exponentiations within the same datapath. We present comprehensive results for a complete processing system that includes the LNU and an OpenRISC based core in 65nm, and 28nm technologies. We compare this implementation with a system using a standard IEEE compliant FPU and show that the LNS based system can outperform its FP counterpart by up to 4.35× in speed. The final, pipelined LNU system when implemented in 65nm occupies an area of 54.3 kGE, allows 89 MFLOP per second and consumes 15.9-136.7 pJ per operation at 1.2V under typical conditions and 25°C.