bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Overview of H.264 Hardware Encoder Architectures Including Low-Power Features
Authors: Nguyen Ngoc-Mai , Bui Duy-Hieu , Dang Nam-Khanh , Beigne Edith , Lesecq Suzanne , Vivet Pascal , Tran Xuan-Tu 
Published: May 2016

H.264 is the most popular video coding standard with high potent coding performance. For its efficiency, the H.264 is expected to encode real-time and/or high-definition video. However, the H.264 standard also requires highly complex and long lasting computation. To overcome these difficulties, many efforts have been deployed to increase encoding speed. Besides, with the revolution of portable devices, multimedia chips for mobile environments are more and more developed. Thus, power-oriented design for H.264 video encoders is currently a tremendous challenge. This paper discusses these trends and presents an overview of the state of the art on power features for different H.264 hardware encoding architectures. We also propose the VENGME’s design, a particular hardware architecture of H.264 encoder that enables applying low-power techniques and developing power-aware ability. This low power encoder is a four-stage architecture with memory access reduction, in which, each module has been optimized. The actual total power consumption, estimated at Register-Transfer-Level (RTL), is only 19.1 mW.
Analysis and Simulation of MRC Diversity Reception in Correlated Composite Nakagami-Lognormal Fading Channels
Authors: Nguyen Dinh Thong , Nguyen Quoc Tuan , Lam Sinh Cong 
Published: May 2016

The physical meaning of the composite Nakagami-lognormal fading model is not well understood by many researchers using the model. The signal power transfer and transform at the interface between the global lognormal shadowing sub-channels and the local Nakagami multipath sub-channels in the presence of correlation between these diversity sub-channels is rather complex. This is the main reason why a thorough analysis or a simulation model is absent to date for the case of correlated composite Nakagami-lognormal diversity channels. This paper presents a novel technique for the estimation of the probability density function (PDF) of the signal-to-noise (SNR) at the output of a maximum ratio combining (MRC) receiver operating in correlated composite diversity fading channels. The PDF is estimated using the recently proposed two-point lossless moment generating function (MGF) matching technique and a closed-form expression for the bit-error rate (BER) for QPSK signal is consequently presented using the Gauss-Hermite polynomial approximation. The paper also presents the complex Monte-Carlo simulation model for the MRC reception and BER counting in correlated composite Nakagami-lognormal fading channels.
Noncoherent Receiver for Decode-and-Forward Cooperative Systems with Multi-Antenna Equipped Destination
Authors: Nguyen Ha X. , Ho Cuu V. , Thai Chan Dai Truyen 
Published: May 2016

This paper studies a maximum energy selection receiver for an adaptive decode-and-forward (DF) cooperative wireless system with multiple-antenna equipped destination. In particular, the destination selects the maximum output from all the outputs of the square-law detectors to perform the detection of the transmitted information. A close-form expression for the bit-error-rate (BER) is analytically derived when the system is deployed with binary frequency-shift keying (BFSK) modulation. The thresholds used at the relays to address the issue of error propagation are optimized to minimize the BER. While finding the optimal thresholds requires information on the average signal-to-noise ratios (SNRs) of all the transmission links in the system, the approximate thresholds at each relay that require only information on the average SNR of the source-corresponding relay are investigated. It is also derived that the system achieves a full diversity order with the approximate thresholds. Finally, both analytical and simulation results are provided to verify our analysis.
A Low Cost and Low Power Consumption Automatic Water Meter Reading System: Hardware Investigation and Network Design
Authors: Nguyen Lap-Luat , Huynh Huu-Tue , Nguyen Tuan-Duc 
Published: May 2016

This paper presents a low power consumption and low cost automatic data collection network for water meter application. Based on transmission performance and power consumption, several low cost sub-GHz wireless transceivers are analyzed and compared, and consequently a suitable hardware is chosen. The associated network protocol stack is also examined. To construct the automatic collecting data mechanism, we consider a cluster based wireless sensor network (WSN) where routers and a GPRS gateway are used to link each cluster to a data collection center. Advantages of this proposed configuration are the simple implementation, low cost and low power consumption. By using the Monte Carlo simulation technique, packet delivery ratio and power consumption for different topologies are investigated. Based on obtained results, the optimum network topology for automatic water meter reading in a typical urban environment is finally proposed.
Multiple-Symbol Differential Detection for Spatial Modulation
Authors: Nguyen Thu Phuong , Le Minh Tuan , Tran Xuan Nam 
Published: May 2016

Approximately 3 dB Signal-to-Noise Ratio (SNR) loss is always paid with conventional Differential Spatial Modulation (DSM) as compared to coherent Spatial Modulation (SM). In this paper, a Multiple-Symbol Differential Detection (MSDD) technique is proposed for DSM systems to mitigate the loss due to differential detection. The new scheme can greatly narrow the 3 dB performance gap by extending the observation interval for differential decoding. The technique uses maximum-likelihood sequence detection instead of traditional symbol-by-symbol detection, and is carried out on the slow, flat Rayleigh fading channel. A generalized decision metric is derived for an observation interval of arbitrary length. It is shown that for a moderate number of symbols, MSDD provides approximately 1.5 dB performance improvement over the conventional differential detection. In addition, a closed-form pairwise error probability and approximate bit error probability (BEP) are derived for multiple-symbol differential spatial modulation. Results show that the theoretical BEP matches well the simulated one. The BEP is shown to converge asymptotically with the number of symbols in the observation interval to that of the differential scheme with coherent detection.
Theoretical and bifurcation analysis of a flexible rotor supported by gas-lubricated bearing system with porous bushing
Authors: Wang Cheng-Chi , Hung Jui-Pin 
Published: May 2016

The bifurcation behaviors of a flexible rotor supported by gas-lubricated bearing system with porous bushing are analyzed by a novel numerical method combining the finite difference method and differential transformation method. The results obtained by proposed method are verified with traditional finite difference method, and the analytical results by these two methods are consistent and also in good agreement. Furthermore, the dynamic orbits, power spectra, bifurcation diagram, Poincaré maps and maximum Lyapunov exponent are used to confirm the changes of rotor behavior as the rotor mass is increased. The results show that the rotor center reveals complex dynamic behaviors including periodic, sub-harmonic and chaotic motions. Especially, the rotor bearing system behaves chaos over the ranges of rotor mass 10.7 ≤ms< 13.8 kg. The current results provide an effective means of the gas bearing systems and further understanding of the nonlinear dynamic behavior of bearing systems characterized by different rotor masses.
Temperature dependence of soft-doped / hard-doped PZT material properties under large signal excitation and impact on the design choice
Authors: Mangeot Charles 
Published: May 2016

Multilayer piezoelectric actuators operating in quasi-static conditions under high electrical field find more and more applications in demanding environments, such as in the field of aerospace. Naturally, increasing amounts of data are being published on the behavior of PZT materials under large signal conditions. However, the information is often incomplete and not directly usable by mechanical design engineers. Using a pragmatic approach, the present work aims at drawing a complete set of parameters for designers to use when selecting a piezoelectric actuator, in particular for applications at elevated temperature (up to 200 °C). For the design process, it is important to characterize apparent capacitance, apparent losses, free stroke, blocking force and height according to temperature. In addition, non-linear effects such as creep must be considered. The present paper focuses mostly on apparent capacitance, losses and displacement. The evolution of capacitance with field is not linear and strongly temperature dependent. Measurements on NCE51 (soft-doped) and NCE46 (hard-doped) indicate a very different behavior. As signal amplitude increases, capacitance increases, reaches a maximum then decreases. This maximum shifts with temperature, so that at 200 °C, NCE51 reaches a maximum at 0,8 kV/mm while NCE46 peaks at 1,8 kV/mm. Results are presented also for the apparent loss factor (tangent δ) and free displacement. At 200 °C, NCE51 and NCE46 provide respectively 23 % and 15 % additional free displacement. Furthermore, the loss factor at maximum field decreases for NCE51, so the basis for material choice (soft-doped or hard-doped) is challenged. Using these measurements, the operating envelope of the actuators can be calculated for different temperatures. The comparison of the two materials highlights the advantage of NCE51 at low frequency. At high frequency, NCE46 maintains an advantage, particularly for energy-intensive applications.
Research on the transmission loss of the floor aluminum profile for the high-speed train based on FE-SEA hybrid method
Authors: Lin Li-zong , Ding Zheng-yin , Zeng Jian-kui , Zhang Chang-xian 
Published: May 2016

Firstly, FEM (Finite Element model) of the aluminum profile is built. The structural material parameters are then given to compute the free modals. After the comparison with the experimental results, the relative error of the modal frequency can be controlled within 5 %, which meets the requirements of CAE analysis. Secondly, pulse decay method is applied to measure damping loss factor of the aluminum profile. As shown from the results, its damping loss factor is 0.15 %-0.35 % within 0 Hz-1600 Hz, which can be used as the input parameter in the subsequent computation of the transmission loss. Thirdly, FE-SEA hybrid method is used to compute the transmission loss of the aluminum profile. As known from the computational results, the transmission loss troughs of the aluminum profile are appeared at 160 Hz, 400 Hz and 800 Hz, whose change trend is basically consistent with the experimental results. Therefore, the sound insulation performance of the aluminum profile at middle and low-frequency band can be reasonably predicted by the simulation model. Finally, based on the verified model of the aluminum profile, the optimization design is conducted on its acoustic-vibro performance from the following aspects such as sound-bridge, plate thickness and structural materials. As a result, a structure with relatively optimal acoustic-vibro performance is obtained.
A Randomized Controlled Trial on the Usefulness of Mobile Text Phone Messages to Improve the Quality of Care of HIV and AIDS Patients in Cameroon
Authors: Nsagha Dickson Shey , Lange Innocent , Fon Peter Nde , Nguedia Assob Jules Clement , Tanue Elvis Asangbeng 
Published: May 2016

Background:HIV and AIDS are major public health problems in the world and Africa. In Cameroon, the HIV prevalence is 5.1%. Cellphones have been found to be useful in the provision of modern health care services using short message services (SMS). This study assessed the effectiveness of SMS in improving the adherence of people living with HIV and AIDS to their treatment and care in Cameroon.Methods:This intervention study used a randomized controlled trial design. Ninety participants seeking treatment at the Nkwen Baptist Health Center were recruited between August and September 2011 using a purposive sampling method. They were randomly allocated into the intervention and control groups, each containing 45 participants. In the intervention group, each participant received four SMSs per week at equal intervals for four weeks. The patients were investigated for adherence to ARVs by evaluating the number of times treatment and medication refill appointments were missed. Data were collected using an interviewer-administered questionnaire before and after intervention and analysed on STATA.Results:The baseline survey indicated that there were 55(61.1%) females and 35(38.9%) males aged 23 - 62 years; the mean age was 38.77 ± 1.08. Most participants were teachers [12 (13.3%)], farmers [11 (12.2%)], and businessmen [24 (26.7%)]. Adherence to ARVs was 64.4% in the intervention group and 44.2% in the control group (p= 0.05). 2(4.4%) patients in the control group failed to respect their drug refill appointments while all the 45(100%) participants in the intervention group respected their drug refill appointments. 54.17% of married people and 42.9% of the participants with primary and secondary levels of education missed their treatment. Key reasons for missing treatment were late home coming (54%), forgetfulness (22.5%), and travelling out of station without medication (17.5%). Other factors responsible for non-adherence included involvement in outdoor business (60.87%), ARV stock out (37.8%), and not belonging to a support group (10.23%). Twenty eight (62.22%) subjects in the intervention group were able to take their treatment regularly and on time.Conclusion:SMS improved adherence to ARVs. Key constraints which affect adhere to ARV medication can be addressed using SMS.
Validating Machine Learning Algorithms for Twitter Data Against Established Measures of Suicidality
Authors: Braithwaite Scott R , Giraud-Carrier Christophe , West Josh , Barnes Michael D , Hanson Carl Lee 
Published: May 2016

Background
One of the leading causes of death in the United States (US) is suicide and new methods of assessment are needed to track its risk in real time.

Objective
Our objective is to validate the use of machine learning algorithms for Twitter data against empirically validated measures of suicidality in the US population.

Methods
Using a machine learning algorithm, the Twitter feeds of 135 Mechanical Turk (MTurk) participants were compared with validated, self-report measures of suicide risk.

Results
Our findings show that people who are at high suicidal risk can be easily differentiated from those who are not by machine learning algorithms, which accurately identify the clinically significant suicidal rate in 92% of cases (sensitivity: 53%, specificity: 97%, positive predictive value: 75%, negative predictive value: 93%).

Conclusions
Machine learning algorithms are efficient in differentiating people who are at a suicidal risk from those who are not. Evidence for suicidality can be measured in nonclinical populations using social media data.
Assessment of vertical changes during maxillary expansion using quad helix or bonded rapid maxillary expander
Authors: Conroy-Piskai Cara , Galang-Boquiren Maria Therese S. , Obrez Ales , Viana Maria Grace Costa , Oppermann Nelson , Sanchez Flavio , Edgren Bradford , Kusnoto Budi 
Published: May 2016

ABSTRACT
Objective: To determine if there is a significantly different effect on vertical changes during phase I palatal expansion treatment using a quad helix and a bonded rapid maxillary expander in growing skeletal Class I and Class II patients.
Materials and Methods: This retrospective study looked at 2 treatment groups, a quad helix group and a bonded rapid maxillary expander group, before treatment (T1) and at the completion of phase I treatment (T2). Each treatment group was compared to an untreated predicted growth model. Lateral cephalograms at T1 and T2 were traced and analyzed for changes in vertical dimension.
Results: No differences were found between the treatment groups at T1, but significant differences at T2 were found for convexity, lower facial height, total facial height, facial axis, and Frankfort Mandibular Plane Angle (FMA) variables. A comparison of treatment groups at T2 to their respective untreated predicted growth models found a significant difference for the lower facial height variable in the quad helix group and for the upper first molar to palatal plane (U6-PP) variable in the bonded expander group.
Conclusion: Overall, both the quad helix expander and the bonded rapid maxillary expander showed minimal vertical changes during palatal expansion treatment. The differences at T2 suggested that the quad helix expander had more control over skeletal vertical measurements. When comparing treatment results to untreated predicted growth values, the quad helix expander appeared to better maintain lower facial height and the bonded rapid maxillary expander appeared to better maintain the maxillary first molar vertical height.
Validation of a Food Frequency Questionnaire for Bone Nutrients in Pregnant Women
Authors: Perreault Maude , Xu Victoria Y. Y. , Hamilton Suzanne , Wright Deslyn , Foster Warren , Atkinson Stephanie A. 
Published: May 2016

Purpose: The aim was to validate a food frequency questionnaire (FFQ) against a 3-day food record (3DFR) for pregnant women with a focus on nutrients important for bone health from food and supplements. Methods: The FFQ and 3DFR were administered to pregnant women (n = 42) aged 18–45 years in their third trimester of pregnancy in Hamilton, Ontario. Nutrient analysis of intakes was conducted using an FFQ calculator and Nutritionist-Pro software. The average daily serving consumption of Milk and alternatives group and Vegetable subgroup from Canada’s Food Guide were also compared. Results: There was a high positive correlation between methods for total dietary vitamin D (r = 0.83). Low positive associations were observed for total protein (r = 0.37), calcium (r = 0.36), vitamin K (r = 0.41), and servings of Milk and alternatives (r = 0.36). A cross-classification analysis using participants’ intake quartiles revealed no major misclassifications. Bland–Altman analysis showed that the FFQ mildly underestimated the intake for protein, whereas it grossly overestimated the intake of vitamin K, and daily servings of Milk and alternatives and Vegetable. Conclusions: This FFQ can serve as a useful tool in clinical and research settings to assess key bone nutrients from foods and supplement sources in pregnant women.
Assessment of Registered Dietitians’ Beliefs and Practices for a Nutrition Counselling Approach
Authors: Taylor Lorian M. , Moriartey Stephanie , Stadnyk Janet , Basualdo-Hammond Carlota 
Published: May 2016

Purpose: This study describes registered dietitians’ (RDs) perceptions and use of a nutrition counselling approach (NCA) as defined by the American Academy of Nutrition and Dietetics Nutrition Care Process terminology (NCPT). Methods: A cross-sectional online survey was administered to approximately 500 RDs in Alberta, Canada. Items included demographics, job characteristics, perceived knowledge, competence, use of an NCA, training experience, and theory of planned behaviour salient beliefs. Descriptive analyses compared RDs who counselled “all or most” of their clients with those who counselled “some or none.” Salient beliefs were analyzed using content analysis. Results: Of the 349 RDs who completed the survey, 64.2% provided an NCA to “all or most” of their patients. RDs were supportive of using an NCA (mean = 8.7/10, SD = 1.9) and most RDs (84.5%) had received training on an NCA. Salient beliefs included advantages (e.g., improved behaviour change in patients) and disadvantages (e.g., inadequate time). Normative referents included colleagues (e.g., multidisciplinary team), managers, patients/clients, College of RDs of Alberta, and counsellors. The barriers and enablers were related to patients’ situations, infrastructure, and RD supports. Conclusions: These results may enable decision makers to more effectively design and target training and implementation programs to improve RDs’ NCA.
Factors Associated with the Intention of Registered Dietitians to Discuss Nutrigenetics with their Patients/Clients
Authors: Bouchard-Mercier Annie , Desroches Sophie , Robitaille Julie , Vohl Marie-Claude 
Published: May 2016

Purpose: The objective of this study was to investigate factors affecting the intention of Registered Dietitians (RDs) to discuss nutrigenetics with their patients/clients. Methods: A survey based on the theory of planned behaviour (TPB; attitude, subjective norm, and perceived behavioural control) was developed and sent by email to RD members of the Ordre professionnel des diététistes du Québec. Multiple regression analyses were performed to examine the determinants of intention and behaviour. Results: A total of 141 RDs completed the questionnaire (5.8% response rate). On a scale from −2 to 2 (from strongly disagree to strongly agree), the intention of discussing nutrigenetics with patients/clients was neutral (mean of −0.07 ± 0.92). The TPB construct of attitude was the most strongly associated with intention (β = 0.66, P < 0.0001) followed by perceived behavioural control (β = 0.33, P < 0.0001) and subjective norm (β = 0.21, P = 0.03). Finally, 13 out of 141 RDs (~9%) actually practiced the behaviour, which was to have discussed nutrigenetics with their patients/clients in the last 3 months. Only perceived behavioural control contributed to explain the behaviour (β = 0.17, P < 0.0001). Conclusions: Main determinants of the intention of RDs to discuss nutrigenetics with their patients/clients were determined. This knowledge will help inform the design of future educational content about nutrigenetics.
HABITABLE ZONES OF POST-MAIN SEQUENCE STARS
Authors: Ramirez Ramses M. , Kaltenegger Lisa 
Published: May 2016

ABSTRACT
Once a star leaves the main sequence and becomes a red giant, its Habitable Zone (HZ) moves outward, promoting detectable habitable conditions at larger orbital distances. We use a one-dimensional radiative-convective climate and stellar evolutionary models to calculate post-MS HZ distances for a grid of stars from 3700 to 10,000 K (∼M1 to A5 stellar types) for different stellar metallicities. The post-MS HZ limits are comparable to the distances of known directly imaged planets. We model the stellar as well as planetary atmospheric mass loss during the Red Giant Branch (RGB) and Asymptotic Giant Branch (AGB) phases for super-Moons to super-Earths. A planet can stay between 200 million years up to 9 Gyr in the post-MS HZ for our hottest and coldest grid stars, respectively, assuming solar metallicity. These numbers increase for increased stellar metallicity. Total atmospheric erosion only occurs for planets in close-in orbits. The post-MS HZ orbital distances are within detection capabilities of direct imaging techniques.