bluuebunny/crossref_metadata_2025 huggingface dataset:
Skill underutilization and collective turnover in a professional service firm
Authors: Mitchell Melissa , Zatzick Christopher D.
Published: July 2015

Purpose

– The purpose of this paper is to examine skill underutilization and collective turnover in a large professional service firm (PSF). The authors hypothesize that skill underutilization is positively related to collective turnover, that skill underutilization is greater among professionals than nonprofessionals, and that the positive relationship between skill underutilization and collective turnover is stronger for professionals than for nonprofessionals.

Design/methodology/approach

– Using survey data from a large PSF, the authors test these predictions across 191 groups (professional and nonprofessional) in 80 offices. Collective turnover rates were taken from company records one year after the survey was administered.

Findings

– The authors find support for the prediction that skill underutilization is positively related to collective turnover. In addition, skill underutilization is greater among professionals than nonprofessionals within a PSF. However, the relationship between skill underutilization and collective turnover did not differ between professionals and nonprofessionals.

Research limitations/implications

– While the authors find that skill underutilization is positively related to collective turnover, future research is needed to measure the group processes that occur among group members and lead to collective turnover. Limitations of this study include the inability to validate the aggregation of data from the individual level to the group level, and the generalizability of findings to other PSFs or to involuntary turnover situations.

Practical implications

– Understanding the antecedents of collective turnover is of particular concern to PSFs, as they are composed of highly skilled, intrinsically motivated professionals, who generate value for the firm. These findings are particularly timely, given the significant levels of underemployment in countries throughout the world.

Originality/value

– In addition to extending skill underutilization and collective turnover research to the occupational group level, the findings highlight the importance of providing development opportunities for employees during difficult economic conditions in order to minimize collective turnover.
Antecedents and outcomes of perceived organizational support: a literature survey approach
Authors: Ahmed Ishfaq , Nawaz Muhammad Musarrat
Published: July 2015

Purpose

– Riggle et al.’s (2009) and Rhoades and Eisenberger (2002) literature surveys are the latest available studies on antecedents and outcomes of perceived organizational support (POS). Riggle et al. work considered studies on outcomes of organizational support (1986-2006), while Rhoades and Eisenberger worked on both antecedents and consequences (1986-2002). There are seven years since no work has been done on the outcomes and almost 12 years since no work has been done on the antecedents of POS. Considering the gap, the paper aims to investigate the antecedents and outcomes of POS.

Design/methodology/approach

– In total, 170 studies were included in meta-analysis containing at least one of the antecedent or outcomes. Riggle et al. included 167 studies, while Rhoades and Eisenberger study covered 70 studies in their literature survey studies for the period of 1986-2006. This study adds value to the work of Riggle et al., by looking at the studies conducted from January 2007 to September 2013; and Rhoades and Eisenberger by investigating the antecedents of POS from January 2003 to September 2013.

Findings

– Findings of the study revealed that POS is largely influenced by justice, growth opportunities, supervisor support, and coworker support. While having a profound look at the outcomes it is evident that POS significantly influence employee engagement, job satisfaction, and organizational commitment; while its impact on organizational citizenship behavior and turnover intentions is moderate.

Practical implications

– This research endeavor leaves a valuable message for management as POS is noticed to have profound effects on employee attitudes and behaviors at work.

Originality/value

– This study adds value by offering meta-analysis of the antecedents and outcomes of POS for latest available literature (i.e. 2003-2013 for antecedents and 2007-2013 for outcomes).
Effective delegation among Hong Kong Chinese male managers: the mediating effects of LMX
Authors: Joiner Therese Anne , Leveson Lynne
Published: July 2015

Purpose

– With the continued expansion of Western organisations and their leadership personnel and practices across national boundaries there is a need for continued critical examination of assumptions about the transferability of these practices into other cultural settings. The purpose of this paper is to focus on one such practice, delegation, and explores its relationship to leader-member exchange (LMX) relationships and work outcomes in a non-Western organisation.

Design/methodology/approach

– Participants (186) were Chinese subordinate managers in a large transport company in Hong Kong. Data were collected via questionnaire and analysed using a path-analytic model.

Findings

– The data supported a direct and indirect path between delegation and job satisfaction and an indirect path only between delegation and job performance where LMX was the mediating variable. The results highlight the importance of LMX in the delegation-work outcomes relationship.

Research limitations/implications

– The limitations of using a single site for investigation, cross-sectional data and common method bias are discussed in relation to suggestions for future research.

Practical implications

– For the company in question, quality LMX relationships are seen as key for improving delegation-work outcome relationships particularly in terms of the potential to “soften” the autonomy requirements of the delegation process for Chinese subordinate managers.

Originality/value

– This research adds new knowledge to the literature about the conditions under which delegation may be effective in improving subordinate job satisfaction and performance through the agency of enhanced LMX relationships in a Chinese work context.
Debriefing a rescue mission during a terror attack
Authors: Firing Kristian , Johansen Linn Therece , Moen Frode
Published: July 2015

Purpose

– The purpose of this paper is to explore a better understanding of Holistic Debriefing processes from a learning perspective.

Design/methodology/approach

– During a terror attack in which 69 people were killed and 66 were wounded, a Search and Rescue crew experienced “fear of death” while giving life-saving help to victims of the attack. Afterwards, the crew conducted a Holistic Debriefing. The crew participated in interviews to share their experience of this type of debriefing.

Findings

– The findings from the Holistic Debriefing sessions suggest that the debriefing process was experienced as positive in terms of social support, emotions and meaning. These experiences are further explained from a learning perspective.

Research limitations/implications

– This research was conducted on a small group of individuals experiencing an extreme situation, and findings may not readily generalize to other populations or situations.

Practical implications

– Holistic Debriefing has been adopted by an increasing number of squadrons in the Norwegian Air Force.

Social implications

– Holistic Debriefing has been implemented at the Norwegian Air Force Academy, and may be relevant for other units involved in similar operations.

Originality/value

– This study is unique when it comes to exploring Holistic Debriefing of rescue personnel in the aftermath of a terror attack. Moreover, Holistic Debriefing is also addressed as a reflection process in order to enhance individual and group learning processes.
Systematic vs intuitive decision making and the Pareto principle
Authors: Cervone H Frank
Published: July 2015

Purpose

– The purpose of this paper is to discuss some of the primary factors that inhibit efficient decision-making in teams and propose some methods to help facilitate the process more effectively. Teams often have a difficult time navigating the decision-making process. Even with a well-defined process, decision-making can be derailed by failing to set and maintain priorities or by ineffectively evaluating the significance of individual decisions that need to be made within the larger project scope.

Design/methodology/approach

– This article reviews some of the applicable literature related to decision-making and synthesizes it into an approach that can be used by teams to facilitate their decision-making processes.

Findings

– There are three major impediments to efficient and effective decision-making in teams. Using methods for diagnosing and triaging the nature of decisions, teams can become more effective and efficient in their decision-making processes.

Originality/value

– This article synthesizes a number of strands of research from various subdisciplines in management to develop an approach that can be used by project teams to more effectively facilitate their decision-making processes.
Streamlined request services: the integration of ILS, ILL and Consortia borrowing systems
Authors: Ye Gan (Grace) , Bryant Sally
Published: July 2015

Purpose

– This paper aims to study streamlined request services based on discrete systems’ integration in an academic library. The integration of discrete systems allows patrons to use the library’s online public access catalog to send requests and have the requests automatically transferred to the local integrated library system (ILS), the consortia borrowing system, and an interlibrary loan system. The integration of discrete systems also allows adding the consortia service without adding any library staff.

Design/methodology/approach

– The authors introduce library holdings behind the search interface, the discrete library systems and the authentication system. The paper illustrates how patron requests can be automatically transferred to discrete library systems.

Findings

– Resource sharing has become a hot topic in the library world where libraries are facing budget cuts, space limits and employee shortage challenges. Systems’ integration will help libraries to add new services without adding staff.

Practical implications

– The consortia borrowing system can be seamlessly integrated into discrete library systems and a campus authentication system. Pepperdine University’s experience can serve as an example for libraries which have a plan to implement consortia borrowing systems or want to streamline their workflows.

Originality/value

– This paper takes a fresh look at the traditional request services using cloud-based systems.
Day-Ahead Solar Irradiance Forecasting in a Tropical Environment
Authors: Aryaputera Aloysius W. , Yang Dazhi , Walsh Wilfred M.
Published: July 2015

Day-ahead solar irradiance forecasting is carried out using data from a tropical environment, Singapore. The performance of the weather research and forecasting (WRF) model is evaluated. We explore various combinations of physics configuration setups in the WRF model and propose a setup for the tropical regions. The WRF model is benchmarked using persistence and two seasonal time series models, namely, the exponential smoothing (ETS) and seasonal autoregressive integrated moving average (SARIMA) models. It is shown that the WRF model outperforms the SARIMA model and achieves accuracies comparable with persistence and ETS models. Persistence, ETS, and WRF models have relative root mean square errors (rRMSE) of about 55–57%. Furthermore, we find that by combining the forecasting outputs of WRF and ETS models, errors can be reduced to 49%.
Review of Buoyancy-Induced Flow in Rotating Cavities
Authors: Michael Owen J. , Long Christopher A.
Published: July 2015

Buoyancy-induced flow occurs in the cavity between two corotating compressor disks when the temperature of the disks and shroud is higher than that of the air in the cavity. Coriolis forces in the rotating fluid create cyclonic and anticyclonic circulations inside the cavity, and—as such flows are three-dimensional and unsteady—the heat transfer from the solid surfaces to the air is difficult either to compute or to measure. As these flows also tend to be unstable, one flow structure can change quasi-randomly to another. This makes it hard for designers of aeroengines to calculate the transient temperature changes, thermal stresses, and radial growth of the disks during engine accelerations and decelerations. This paper reviews published research on buoyancy-induced flow in closed rotating cavities and in open cavities with either an axial throughflow or a radial inflow of air. In particular, it includes references to experimental data that could be used to validate cfd codes and numerical models.
Numerical Shape Optimization of a Wind Turbine Blades Using Artificial Bee Colony Algorithm
Authors: Derakhshan Shahram , Tavaziani Ali , Kasaeian Nemat
Published: July 2015

Use of wind turbines is rapidly growing because of environmental impacts and daily increase in energy cost. Therefore, improving the wind turbines' characteristics is an important issue in this regard. This study has two objectives: one is investigating the aerodynamic performance of wind turbine blades and the other is developing an efficient approach for shape optimization of blades. The numerical solver of flow field was validated by phase VI rotor as a case study. First, flow field around the wind turbine blades was simulated using computational flow dynamics (CFD) and blade element momentum (BEM) methods, then obtained results were validated by available experimental data to show an appropriate conformity. Then for yielding the optimal answer, a shape optimization algorithm was used based on artificial bee colony (ABC) coupled by artificial neural networks (ANNs) as an approximate model. Effect of most important parameters in wind turbine, such as twist angle, chord line, and pitch angle, was changed till achieving the best performance. The flow characteristics of optimized and initial geometries were compared. The results of global optimization showed a value of 8.58% increase for output power. By using pitch power regulate, the maximum power was shifted to higher wind speed and results in a steady power for all work points.
Pair Selection Analysis in Differential RSSI Based Localization
Authors: Mehdi Dehghan S. M. , Moradi Hadi , Asghar Shahidian S. A.
Published: July 2015

Differential received signal strength indicator (DRSSI), in which two separate received signal strength indicator (RSSI) measurements are used to localize an radio frequency (RF) source with unknown transmitted power, has been proposed to eliminate the need for estimating the strength of the transmitted signal in localization. In this paper, the problem of choosing the best pair of measurements, which can lead to close-to-minimum localization error based on Cramer–Rao lower bound (CRLB) analysis, is addressed. The analysis shows that the root mean squared error (RMSE) of localization decreases monotonically with the increase of the angle between two pairing measurements, with respect to the target, up to 180 deg. In other words, it is shown that the best pair of measurements consists of the measurement points which are inline with the target opposing each other. The second best pairing angle is near 135 deg with respect to the target. To practically show the importance of this analysis, several Monte Carlo simulation scenarios were conducted which show that the RMSE of localization would be close-to-minimum using the proposed analysis.
A Multivariable Newton-Based Extremum Seeking Control for Condenser Water Loop Optimization of Chilled-Water Plant
Authors: Mu Baojie , Li Yaoyu , Seem John E. , Hu Bin
Published: July 2015

This paper presents a multivariable Newton-based extremum seeking control (ESC) scheme for efficient operation of a chilled-water plant. A modelica-based dynamic simulation model of the chilled-water plant consists of one screw chiller and one counter-flow cooling tower was adopted for evaluation of proposed two-input Newton-based ESC controller. The ESC controller takes the total power of the chiller compressor, the cooling-tower fan, and the condenser water (CW) pump as feedback signal and discovers the optimum outputs of cooling-tower fan speed and the condenser-loop water flow rate to maximize the power efficiency in real time with the cooling load being satisfied. Remarkable energy saving is observed for several testing conditions.
A multi‐institutional study to assess adherence to lung stereotactic body radiotherapy planning goals
Authors: Woerner Andrew , Roeske John C. , Harkenrider Matthew M. , Fan John , Aydogan Bulent , Koshy Matthew , Laureckas Robert , Vali Faisal , Campana Maria , Surucu Murat
Published: July 2015

Purpose:

A multi‐institutional planning study was performed to evaluate the frequency that current guidelines established by Radiation Therapy Oncology Group (RTOG) protocols and other literature for lung stereotactic body radiotherapy (SBRT) treatments are followed.

Methods:

A total of 300 patients receiving lung SBRT treatments in four different institutions were retrospectively reviewed. The treatments were delivered using Linac based SBRT (160 patients) or image guided robotic radiosurgery (140). Most tumors were located peripherally (250/300). Median fractional doses and ranges were 18 Gy (8–20 Gy), 12 Gy (6–15 Gy), and 10 Gy (5–12 Gy) for three, four, and five fraction treatments, respectively. The following planning criteria derived from RTOG trials and the literature were used to evaluate the treatment plans: planning target volumes, PTVV 100 ≥ 95% and PTVV 95 ≥ 99%; conformality indices, CI100% < 1.2 and CI50% range of 2.9–5.9 dependent on PTV; total lung‐ITV: V20Gy < 10%, V12.5Gy < 15%, and V5Gy < 37%; contralateral lung V5Gy < 26%; and maximum doses for spinal cord, esophagus, trachea/bronchus, and heart and great vessels. Populations were grouped by number of fractions, and dosimetric criteria satisfaction rates (CSRs) were reported.

Results:

Five fraction regimens were the most common lung SBRT fractionation (46%). The median PTV was 27.2 cm3 (range: 3.8–419.5 cm3). For all plans: mean PTVV 100 was 94.5% (±5.6%, planning CSR: 69.8%), mean PTVV 95 was 98.1% (±4.1%, CSR: 69.5%), mean CI100% was 1.14 (±0.21, CSR: 79.1%, and 16.5% within minor deviation), and mean CI50% was 5.63 (±2.8, CSR: 33.0%, and 28.0% within minor deviation). When comparing plans based on location, peripherally located tumors displayed higher PTVV 100 and PTVV 95 CSR (71.5% and 71.9%, respectively) than centrally located tumors (61.2% and 57.1%, respectively). Overall, the planning criteria were met for all the critical structure such as lung, heart, spinal cord, esophagus, and trachea/bronchus for at least 85% of the patients.

Conclusions:

Among the various parameters that were used to evaluate the SBRT plans, the CI100% and CI50% were the most challenging criteria to meet. Although the CSRs of organs at risk were higher among all cases, their proximity to the PTV was a significant factor.
Effects of vocal fold epithelium removal on vibration in an excised human larynx model
Authors: Tse Justin R. , Zhang Zhaoyan , Long Jennifer L.
Published: July 2015

This study investigated the impact of selective epithelial injury on phonation in an excised human larynx apparatus. With intact epithelium, the vocal folds exhibited a symmetrical vibration pattern with complete glottal closure during vibration. The epithelium was then enzymatically removed from one, then both vocal folds, which led to left-right asymmetric vibration and a decreased closed quotient. Although the mechanisms underlying these vibratory changes are unclear, these results demonstrate that some component of an intact surface layer may play an important role in achieving normal symmetric vibration and glottal closure.
Psychometric and Physiological Responses to a Preseason Competitive Camp in the Heat With a 6-Hour Time Difference in Elite Soccer Players
Authors: Buchheit Martin , Cholley Yannick , Lambert Philippe
Published: July 2015

Purpose:

To examine in elite soccer players after traveling across 6 time zones some psychometric and physiological responses to a competitive camp in the heat.

Methods:

Data from 12 elite professional players (24.6 ± 5.3 y) were analyzed. They participated in an 8-d preseason summer training camp in Asia (heat index 34.9°C ± 2.4°C). Players’ activity was collected during all training sessions and the friendly game using 15-Hz GPS. Perceived training/playing load was estimated using session rating of perceived exertion (RPE) and training/match duration. Psychometric measures of wellness were collected on awakening before, during, and after the camp using simple questionnaires. Heart-rate (HR) response to a submaximal 4-min run (12 km/h) and the ratio between velocity and force-load (accelerometer-derived measure, a marker of neuromuscular efficiency) response to four ~60-m runs (22–24 km/h) were collected before, at the end of, and after the camp.

Results:

After a large increase, the RPE:m/min ratio decreased substantially throughout the camp. There were possible small increases in perceived fatigue and small decreases in subjective sleep quality on the 6th day. There were also likely moderate (~3%) decreases in HR response to the submaximal run, both at the end of and after the camp, which were contemporary to possible small (~8%) and most likely moderate (~19%) improvements in neuromuscular efficiency, respectively.

Conclusions:

Despite transient increases in fatigue and reduced subjective sleep quality by the end of the camp, these elite players showed clear signs of heat acclimatization that were associated with improved cardiovascular fitness and neuromuscular running efficiency.
Maximal Velocity as a Discriminating Factor in the Performance of Loaded Squat Jumps
Authors: Jiménez-Reyes Pedro , Pareja-Blanco Fernando , Rodríguez-Rosell David , Marques Mario C. , González-Badillo Juan José
Published: July 2015

Purpose:

To determine what variables determine the differences in performance on 2 tests of squat jump (SJ) performed under light load in highly trained athletes using maximal velocity (Vmax) or flight time (FT) as the discriminating factor of SJ performance.

Methods:

Thirty-two participants performed 2 maximal weighted SJs using a force platform synchronized with a linear transducer. Mean force (Fmean), mean and maximal power (Pmean, Pmax), peak force (PF), maximal rate of force development (RFDmax), and time required to attain PF (TPF) and RFDmax (TRFDmax) were analyzed. SJs were divided into 2 segments: from the initiation of force application to PF1 and from the moment after PF1 to Vmax.

Results:

Traditional significance statistics revealed significant differences in the same variables between best and worst SJs using both FT and Vmax. However, to use an approach based on the magnitude of the effect, the best SJ showed greater Pmax (83/17/0%), Pmean (85/15/0%), Fmean (71/29/0%), RFDmax1 (73/27/0%), and PF1 (53/47/0%) and lower TPF2 (0/61/39%) than the worst SJ when Vmax was used to discriminate SJ performance. However, using FT to differentiate SJ performance, no difference was observed between best and worst.

Conclusions:

Although jump height assessed through FT is a valid measure, these results suggest that Vmax is a more sensitive variable than FT to detect differences in loaded-SJ performance.
Randomized Control Trial Investigating the Effects of Kinesiology Tape on Shoulder Proprioception
Authors: Burfeind Sean M. , Chimera Nicole
Published: July 2015

Context:

Athletes participating in upper-extremity-dominant sports such as softball and volleyball are at increased risk for glenohumeral-joint pain and injury. For these athletes, an integral part of many injuryprevention and -rehabilitation programs includes improving joint proprioception. One way to measure joint proprioception is through the reproduction of joint angles, or joint-reposition sense (JRS). Kinesiology tape is purported to enhance neuromuscular feedback; therefore, it may influence JRS. However, conflicting findings and the lack of research in the upper extremity warrant further investigation.

Objective:

To determine the effects of kinesiology tape on shoulder-joint proprioception by actively reproducing joint angles, or measurement of JRS.

Design:

Randomized controlled trial.

Setting:

College laboratory.

Participants:

9 men and 7 women 24 ± 3 y old.

Intervention:

SpiderTech kinesiology tape precut Shoulder Spider was applied to the shoulder of participants block randomized to the experimental group, following product-specific instructions, to measure its influence on JRS compared with a control group.

Main Outcome Measurement:

JRS-error scores in shoulder flexion, extension, internal rotation, and external rotation (ER).

Results:

There was a significant interaction between groups pre- to postintervention resulting in decreased JRS errors in flexion (P = .04) and ER (P = .03) in the experimental compared with the control group. The 95% confidence intervals suggest a clinically relevant difference in the variability of JRS errors between postintervention movements for the experimental group in flexion and ER, such that the control group demonstrated much more variability in JRS errors than the experimental group.

Conclusions:

After the application of kinesiology tape the JRS errors were smaller in flexion and ER. This may be of clinical significance in improving proprioception and thus improving joint stability. Additional research should determine the effectiveness of kinesiology tape in reducing joint injury.
Biomechanical Analysis of the Closed Kinetic Chain Upper-Extremity Stability Test
Authors: Tucci Helga T. , Felicio Lilian R. , McQuade Kevin J. , Bevilaqua-Grossi Debora , Camarini Paula Maria Ferreira , Oliveira Anamaria S.
Published: July 2015

Context:

The closed kinetic chain upper-extremity stability (CKCUES) test is a functional test for the upper extremity performed in the push-up position, where individuals support their body weight on 1 hand placed on the ground and swing the opposite hand until touching the hand on the ground, then switch hands and repeat the process as fast as possible for 15 s.

Objective:

To study scapular kinematic and kinetic measures during the CKCUES test for 3 different distances between hands.

Design:

Experimental.

Setting:

Laboratory.

Participants:

30 healthy individuals (15 male, 15 female).

Main Outcome Measures:

Participants performed 3 repetitions of the test at 3 distance conditions: original (36 in), interacromial, and 150% interacromial distance between hands. Participants completed a questionnaire on pain intensity and perceived exertion before and after the procedures. Scapular internal/external rotation, upward/downward rotation, and posterior/anterior tilting kinematics and kinetic data on maximum force and time to maximum force were measured bilaterally in all participants. Percentage of body weight on upper extremities was calculated. Data analyses were based on the total numbers of hand touches performed for each distance condition, and scapular kinematics and kinetic values were averaged over the 3 trials. Scapular kinematics, maximum force, and time to maximum force were compared for the 3 distance conditions within each gender. Significance level was set at α = .05.

Results:

Scapular internal rotation, posterior tilting, and upward rotation were significantly greater in the dominant side for both genders. Scapular upward rotation was significantly greater in original distance than interacromial distance in swing phase. Time to maximum force in women was significantly greater in the dominant side.

Conclusion:

CKCUES test kinematic and kinetic measures were not different among 3 conditions based on distance between hands. However, the test might not be suitable for initial or mild-level rehabilitation due to its challenging requirements.
ClC-3 chloride channel functions as a mechanically sensitive channel in osteoblasts
Authors: Wang Huan , Wang Rong , Wang Zhe , Liu Qian , Mao Yong , Duan Xiaohong
Published: July 2015

Mechanical stimulation usually causes the volume changes of osteoblasts. Whether these volume changes could be sensed by the ClC-3 chloride channel, a volume-sensitive ion channel, and further promote the osteodifferentiation in osteoblasts has not been determined. In this study, we applied persistent static compression on MC3T3-E1 cells to detect the expression changes of ClC-3, osteogenic markers, as well as some molecules related with signaling transduction pathway. We tested the key role of ClC-3 in transferring the mechanical signal to osteoinduction by ClC-3 overexpressing and siRNA technique. We found that ClC-3 level was up-regulated by mechanical stimulation in MC3T3-E1 cells. Mechanical force also up-regulated the mRNA level of osteogenic markers such as alkaline phosphatase (Alp), bone sialoprotein (Bsp), and osteocalcin (Oc), which could be blocked or strengthened by Clcn3 siRNA or overexpressing, and Alp expression was more sensitive to the changes of ClC-3 level. We also found that runt-related transcription factor 2 (Runx2), transforming growth factor beta 1 (TGF-β1), and Wnt pathway might be involved in ClC-3 mediated mechanical transduction in osteoblasts. The data from the current study suggest that the ClC-3 chloride channel acts as a mechanically sensitive channel to regulate osteodifferentiation in osteoblasts.
Determination of epinephrine in human serum using a Pt electrode modified by polyaniline–poly(3-methylthiophene)–poly(3,3′-diaminobenzidine)
Authors: Ülker Emine , Kavanoz Muammer
Published: July 2015

A Pt electrode modified by polyaniline–poly(3-methylthiophene)–poly(3,3′-diaminobenzidine) was used for amperometric determination of epinephrine in a solution of NaHSO4/Na2SO4 (pH 2.0). For these studies, potentials between 0.40 and 0.50 V were applied, and the best response was obtained at 0.45 V. The limit of detection, limit of quantification, and the linear dynamic range were 1.23 × 10−4, 4.10 × 10−4, and 4.10 × 10−4 to 100.0 mmol L−1, respectively. These results were compared with determinations using Pt electrodes that were coated and uncoated with homopolymers. To check the accuracy of the developed method and the matrices interference, determination of epinephrine was performed in human serum samples using this modified electrode. The epinephrine concentrations were adjusted to 1.0 and 5.0 mmol L−1, and recovery values were calculated as 100.4% and 96.8%, respectively. It is significant that the determination of epinephrine was carried out at a lower potential (0.45 V) than the oxidation potential of epinephrine (0.65 V) without any matrix effect.
A new cobalt(II)-containing coordination polymer composed of dinuclear metal units: synthesis, crystal structure, and magnetic properties with DFT calculations
Authors: Liu Xiangyu , Liu Huaixian , Zhou Huiliang , Cen Peipei , Jin Xiaoyong , Song Weiming , Luo Shuchang , Hu Qilin
Published: July 2015

A new Co(II)-based compound with a 3-phenyl-5-(pyridin-4-yl)-1,2,4-triazole (4-Hppt) and isophthalic acid (H2ip) mixed ligand, [Co(4-Hppt)2(ip)] (1), has been synthesized and structurally and magnetically characterized. The structure of compound 1 consists of one-dimensional coordination chains based on the Co2 units bridged by dual carboxylate groups, where the pyridyl nitrogen atoms in 4-Hppt ligands are located in the axial coordination sites of the octahedral Co(II) nodes. Magnetic investigation suggests that the magnetic coupling derived from the dinuclear Co(II) ions is a moderately antiferromagnetic exchange in the title compound. Moreover, DFT calculations have been performed on the compound to offer a qualitatively theoretical explanation of the magnetic behavior.
Multi-indexed extensions of soliton potential and extended integer solitons of KdV equation
Authors: Ho Choon-Lin , Lee Jen-Chi
Published: July 2015

We calculate infinite set of initial profiles of higher integer Korteweg–de Vries (KdV) solitons, which are both exactly solvable for the Schrödinger equation and for the Gel’fand–Levitan–Marchenko (GLM) equation in the inverse scattering transform (IST) method of KdV equation. The calculation of these higher integer soliton solutions is based on the recently developed multi-indexed extensions of the reflectionless soliton potential.
Application of robust estimation methods to simple models of nucleon separation energies
Authors: Baselga S.
Published: July 2015

Some works have recently shown the usefulness of simple models of nucleon separation energies in terms of neutron and proton numbers. However, the customary use of least squares in the process of parameter estimation turns out to be extremely sensible to the accuracy of the model and the extent and quality of data (e.g. highly vulnerable to the sample size or the possible existence of undesired errors in the experimental values). We will show how robust estimation by global optimization instead of least squares estimation improves on both the stability of the estimated parameters and the extrapolation to unknown energies. Comparison against recently determined experimental data will show a level of agreement comparable to the predictions made by the best and much more complex models.
Improved fD(s)∗, fB(s)∗ and fBc from QCD Laplace sum rules
Authors: Narison Stephan
Published: July 2015

Anticipating future precise measurements of the D- and B-like (semi)leptonic and hadronic decays for alternative determinations of the CKM mixing angles, we pursue our program on the D- and B-like mesons by improving the estimates of [Formula: see text] and [Formula: see text] (analogue to [Formula: see text]) by using the well-established (inverse) Laplace sum rules (LSR) and/or their suitable ratios less affected by the systematics, which are known to N2LO pQCD and where the complete [Formula: see text] nonperturbative condensate contributions are included. The convergence of the PT series is analyzed by an estimate of the N3LO terms based on geometric growth of the coefficients. In addition to the standard LSR variable [Formula: see text] and the QCD continuum threshold [Formula: see text] stability criteria, we extract our optimal results by also requiring stability on the variation of the arbitrary QCD subtraction point [Formula: see text] which reduces the errors in the analysis. We complete the study of the open bottom states by an estimate of [Formula: see text]. Our results summarized in Tables 3 and 4 are compared with some other recent sum rules and lattice estimates.
Weak magnetic field effects on chiral critical temperature in a nonlocal Nambu–Jona-Lasinio model
Authors: Loewe M. , Marquez F. , Villavicencio C. , Zamora R.
Published: July 2015

In this paper we study the nonlocal Nambu–Jona-Lasinio model with a Gaussian regulator in the chiral limit. Finite temperature effects and the presence of a homogeneous magnetic field are considered. The magnetic evolution of the critical temperature for chiral symmetry restoration is then obtained. Here, we restrict ourselves to the case of low magnetic field values, being this a complementary discussion to the existing analysis in nonlocal models in the strong magnetic field regime.
Scattering states of Dirac equation in the presence of cosmic string for Coulomb interaction
Authors: Hosseinpour M. , Hassanabadi H.
Published: July 2015

We study the covariant Dirac equation in the space–time generated by a cosmic string in presence of vector and scalar potentials of electromagnetic field. We obtain the solution of the radial part of Dirac equation. We consider the scattering states under the Coulomb potential and obtain the phase shifts.
Electroweak scale invariant models with small cosmological constant
Authors: Foot Robert , Kobakhidze Archil
Published: July 2015

We consider scale invariant models where the classical scale invariance is broken perturbatively by radiative corrections at the electroweak scale. These models potentially offer an elegant and simple solution to the hierarchy problem. If we further require the cosmological constant to be small then such models are also highly predictive. Indeed, the minimal such model, comprizing a Higgs doublet and a real singlet, has the same number of parameters as the standard model. Although this minimal model is disfavored by recent LHC data, we show that two specific extensions incorporating neutrino masses and dark matter are fully realistic. That is, consistent with all experiments and observations. These models predict a light pseudo-Goldstone boson, h, with mass around 10 GeV or less. A fermionic-bosonic mass relation is also predicted. The specific models considered, as well as more generic scale invariant models, can be probed at the LHC.
Self-similarity of hadron production in pp and AA collisions at high energies
Authors: Artemenkov D. A. , Lykasov G. I. , Malakhov A. I.
Published: July 2015

We analyze the self-similarity approach applied to study the hadron production in pp and AA collisions. This approach allows us to describe rather well the ratio of the proton to antiproton yields in AA collisions as a function of the energy at a wide range from a few GeV to a few TeV. We suggest a modification of this approach to describe rather well the inclusive spectra of hadrons produced in pp collisions at different initial energies from the AGS to LHC.
A stochasticity threshold in holography and the instability of AdS
Authors: Basu Pallab , Krishnan Chethan , Saurabh Ayush
Published: July 2015

We give strong numerical evidence that a self-interacting probe scalar field in AdS, with only a few modes turned on initially, will undergo fast thermalization only if it is above a certain energetic threshold. Below the threshold the energy stays close to constant in a few modes for a very long time instead of cascading quickly. This indicates the existence of a Strong Stochasticity Threshold (SST) in holography. The idea of SST is familiar from certain statistical mechanical systems, and we suggest that it exists also in AdS gravity. This would naturally reconcile the generic nonlinear instability of AdS observed by Bizon and Rostworowski, with the Fermi–Pasta–Ulam–Tsingou-like quasiperiodicity noticed recently for some classes of initial conditions. We show that our simple setup captures many of the relevant features of the full gravity-scalar system.
Computational investigations of mechanical and vibrational properties of quaternary semiconductor alloys MgxZn1-xSySe1-y
Authors: Jivani A. R. , Jani A. R.
Published: July 2015

Physical properties like elastic constants, pressure derivative of bulk modulus, pressure derivative of elastic constants and acoustic wave velocities in different directions for Mg x Zn 1-x S , Mg x Zn 1-x Se and ZnS y Se 1-y semiconductor ternary alloys and Mg x Zn 1-x S y Se 1-y quaternary alloys with different concentrations of x and y are studied using our previously proposed potential based on the pseudopotential formalism. It is noticed from the present study that the physical properties under investigations depend on concentrations x and y of constitute compounds. The present results of various physical quantities of compounds presented here are compared with the available experimental data and other theoretical estimations and showed roughly reasonable agreement. The numerical values of same quantities for ternary alloys and MgZnSSe quaternary alloys were reported first time and hence such results may be useful for comparison purpose in future with either the experimental or the theoretical work.
Analysis of experimental data for two-band superconductors at T ≈ Tc using the GL theory in the presence of a self-consistent vortex line
Authors: Macias-M Alfredo , Rodríguez-Núñez J. J. , Bonalde Ismardo , Schmidt A. A.
Published: July 2015

We study the two-component Ginzburg–Landau (GL) theory, in the presence of a self-consistent vortex line, to obtain the penetration depth (λ) and the effective healing length (ξ), in the asymptotic limit r → ∞. All these parameters versus T/Tc are analyzed for the materials MgB 2, V 3 Si and LiFeAs in the interval 0.88 ≤ T/Tc ≤ 1.0, where the GL theory is assumed to be valid. We find that κ ≡ λ/ξ, which is another parameter not related to the GL parameter, is T-independent for V 3 Si and LiFeAs , while is T-dependent for the compound MgB 2. This result suggests that even though all these three materials display two-gap superconductivity overall, near Tc superconductivity in V 3 Si and LiFeAs seems to be different from the one in MgB 2. The use of this parameter, κ, as a new way to "study" the superconducting materials, under the presence of a single vortex, is valid for 0.88Tc≲ T ≤ Tc, namely, in the GL formalism.
Fingertip Detection and Gesture Recognition Based on Contour Approximation
Authors: Wang Mei , Lin Jzau-Sheng , Meng Guo Qing
Published: July 2015

In this paper, a new recognition algorithm was developed based on the skin color model and the fingertip structure detection to improve the hand gesture recognition accuracy based on the traditional Hu's moment features. Firstly, the geometric features and the areas of skin were adopted to segment the skin region from the background. The Douglas–Peucker (D–P) algorithm was utilized to conduct the contour approximation to get a polygonal in the process of feature detection. Then the convexity point inspections were conducted in the polygonal. Secondly, we developed two rules for locating and numbering the fingertips. After that, we built a seven-dimensional feature vector. Finally, the hand gesture was recognized by using the distance matching criterion. The developed recognition algorithm improved the recognition accuracy by 2.7% compared with the traditional Hu's moment features. Additionally, it has good robustness in several manners such as shifting, plane rotation and scaling.
A Hierarchical Regression Approach for Unconstrained Face Analysis
Authors: Liu Yuanyuan , Chen Jingying , Shan Cunjie , Su Zhiming , Cai Pei
Published: July 2015

Head pose and facial feature detection are important for face analysis. However, many studies reported good results in constrained environment, the performance could be decreased due to the high variations in facial appearance, poses, illumination, occlusion, expression and make-up. In this paper, we propose a hierarchical regression approach, Dirichlet-tree enhanced random forests (D-RF) for face analysis in unconstrained environment. D-RF introduces Dirichlet-tree probabilistic model into regression RF framework in the hierarchical way to achieve the efficiency and robustness. To eliminate noise influence of unconstrained environment, facial patches extracted from face area are classified as positive or negative facial patches, only positive facial patches are used for face analysis. The proposed hierarchical D-RF works in two iterative procedures. First, coarse head pose is estimated to constrain the facial features detection, then the head pose is updated based on the estimated facial features. Second, the facial feature localization is refined based on the updated head pose. In order to further improve the efficiency and robustness, multiple probabilitic models are learned in leaves of the D-RF, i.e. the patch’s classification, the head pose probabilities, the locations of facial points and face deformation models (FDM). Moreover, our algorithm takes a composite weight voting method, where each patch extracted from the image can directly cast a vote for the head pose or each of the facial features. Extensive experiments have been done with different publicly available databases. The experimental results demonstrate that the proposed approach is robust and efficient for head pose and facial feature detection.
An ANN Model to Estimate the Impact of Tea Process Parameters on Tea Quality
Authors: Saikia Debashis , Sarma Diganta Kumar , Boruah P. K. , Sarma Utpal
Published: July 2015

Present study deals with the development of an artificial neural network (ANN)-based technique for tea quality quantification by monitoring fermentation and drying condition of the tea processing stages. An RS485 network-based instrumentation system has been developed and implemented for data collection for these two stages. Three calibrated sensor nodes are installed in the fermentation room due to its larger floor area to collect temperature and relative humidity (RH). Dryer inlet temperature is recorded using a calibrated thermocouple-based sensor node. From seven input parameters and target quality data obtained from tea taster, the ANN model has been developed to find the correlation between the process condition and the tea quality. From the correlation study, more than 90% classification rate is obtained from the model. The model is also validated with some independent data showing more than 60% correlation. Error in terms of root mean square error (RMSE) is about 0.17. This model will be helpful for improvement of tea quality.
Timing Analysis of TTEthernet Traffic
Authors: Kermia Omar
Published: July 2015

Over time, more and more systems are becoming mixed-criticality systems. As the complexity and size of these systems grow, computation/communication resources should be more efficient than with traditional systems. Time-triggered (TT) Ethernet is a communication infrastructure that enables the use of a single physical communication infrastructure for distributed mixed-criticality applications while providing timely determinism. TTEthernet distinguishes between two traffic categories: The standard event-triggered (ET) traffic and the TT traffic. The latter, for which higher priority is granted, is subject to strong timing guarantees because of strict-periodicity constraint which fixes start-time cycles of TT messages. In addition, messages in an ET Ethernet traffic, which are of lower priority, have a minimum time interval between their transmission. The focus of this paper is on the timing analysis of a TTEthernet traffic by proposing: (i) A feasibility condition allowing to assess the timing requirements of TT messages. (ii) A schedulability condition allowing to check the schedulability of ET messages by taking into account of TT messages scheduling and idle times.
ECOLOGICAL SUSTAINABILITY OF AN OPTIMAL CONTROLLED SYSTEM INCORPORATING PARTIAL CLOSURE FOR THE POPULATIONS
Authors: CHAKRABORTY KUNAL , HALDAR SAMADYUTI , KAR T. K.
Published: July 2015

This paper describes a prey–predator fishery model incorporating partial closure for the populations. It is assumed that the predator population partially dependent on a logistically growing resource with Beddington–De Angelis type functional response. The proposed system also reflects the dynamic interaction between the net economic revenue and the fishing effort used to harvest the populations. The steady states of the system are determined and the dynamic behavior of the system is discussed. The existence of Hopf bifurcation phenomenon is examined at the interior equilibrium point of the proposed system. We have adopted partial closure for the populations as a controlling instrument to regulate the harvesting of the populations. A dynamic framework towards the optimal utilization of the resource is developed using Pontryagin's maximum principle. The optimal system is numerically solved using an iterative method with Runge–Kutta fourth-order scheme. Simulation results show that the optimal control scheme can achieve a sustainable ecosystem. Results are analyzed with the help of graphical illustrations.