79 research outputs found
Enhancing the performance of energy harvesting wireless communications using optimization and machine learning
The motivation behind this thesis is to provide efficient solutions for energy harvesting communications. Firstly, an energy harvesting underlay cognitive radio relaying network is investigated. In this context, the secondary network is an energy harvesting network. Closed-form expressions are derived for transmission power of secondary source and relay that maximizes the secondary network throughput. Secondly, a practical scenario in terms of information availability about the environment is investigated. We consider a communications system with a source capable of harvesting solar energy. Two cases are considered based on the knowledge availability about the underlying processes. When this knowledge is available, an algorithm using this knowledge is designed to maximize the expected throughput, while reducing the complexity of traditional methods. For the second case, when the knowledge about the underlying processes is unavailable, reinforcement learning is used. Thirdly, a number of learning architectures for reinforcement learning are introduced. They are called selector-actor-critic, tuner-actor-critic, and estimator-selector-actor-critic. The goal of the selector-actor-critic architecture is to increase the speed and the efficiency of learning an optimal policy by approximating the most promising action at the current state. The tuner-actor-critic aims at improving the learning process by providing the actor with a more accurate estimation about the value function. Estimator-selector-actor-critic is introduced to support intelligent agents. This architecture mimics rational humans in the way of analyzing available information, and making decisions. Then, a harvesting communications system working in an unknown environment is evaluated when it is supported by the proposed architectures. Fourthly, a realistic energy harvesting communications system is investigated. The state and action spaces of the underlying Markov decision process are continuous. Actor-critic is used to optimize the system performance. The critic uses a neural network to approximate the action-value function. The actor uses policy gradient to optimize the policy\u27s parameters to maximize the throughput
The impact of internal service quality on job satisfaction in the hotel industry
Service quality is a key factor for success in any hotel. Many researchers have conducted studies on service quality, but only a few studies have been conducted on internal service quality (ISQ) in general, and in the hotel industry in particular. Since there is no general agreement among researchers on the measurement of ISQ, many studies have used SERVQUAL instrument to measure the employees’ perceptions of ISQ. The purpose of this study is to explore the influence of ISQ on employee’s job satisfaction in five-star hotels in Jordan. The current study was carried out by measuring the data gathered through a seven-point Likert scale. The quantitative survey method was applied, and therefore the SERVQUAL instrument was used to measure ISQ, and the Job Satisfaction Survey (JSS) was used to measure job satisfaction. Data obtained from a sample of 238 respondents drawn from 14 five-star hotels in Jordan were analysed with the SPSS software based on descriptive statistics. The study’s findings indicated that the ISQ of five-star hotels in Jordan has a significantly positive influence on an employee’s job satisfaction. These findings support the hypothesis that there is a positive relationship between ISQ in the hotel industry and industry employees’ job satisfaction.Keywords: hotels, internal service quality, job satisfactio
The Impact of Total Quality Management Implementation on Employees’ Service Recovery Performance in Five-Star Hotels in Jordan
The aim of this paper is to examine the impact of total quality management (TQM) implementations on employees’ service recovery performance in five-star hotels in Jordan. TQM implementations and service recovery performance have received significant attention in previous research. However, the impact of TQM on service recovery performance has remained unexplored research area. A 67-item questionnaire, measuring TQM implementations and service recovery, was distributed to 400 employees in 12 five-star hotels in Jordan with a 63.5 response rate. Principle Component Analysis was utilized to determine the factor structure for both TQM and service recovery and Regression Analysis to determine the impact of TQM implementations on service recovery performance. The result revealed that the TQM implementations in five-star hotels in Jordan was implemented effectively and thus, have a positive impact on employees’ service recovery performance. This result is attributed to be unique and this is due to the fact that previous studies have focused on manufacturing sector not on hotel sector in measuring either TQM implementations or service recovery performance. This paper suggests replicating the study in additional settings to determine if similar results will be obtained outside five-star-hotels in Jordan. Many of the previous studies on TQM and service recovery performance have been conducted in the context of western economies and very little research has been done in the Middle East in general and Jordan in particular. As such, there is a need to examine, from the employees’ perspective, the levels of implementing TQM that are being encouraged in the hospitality industry and it is effect on service recovery performance among employees towards their both employers and customers. The present paper contributes to filling the gap in the literature by measuring the TQM implementations and service recovery as a whole in a new context. Keywords: Total Quality Management (TQM), Service Failure, Service Recovery Performance, Hotels, Jordan
Genotype and Haplotype Analysis of ABCB1 at 1236, 2677 and 3435 among Jordanian Population
Purpose: To determine the frequencies of important allelic variants and their haplotype frequencies of the gene among Jordanian population and to compare findings with those reported for other ethnic groups.Methods: Genotyping of ABCB1 (C1236T, G2677T/A and C3435T) was carried out on unrelated healthy Jordanian subjects. Different allelic variants were determined using polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP). The haplotype frequencies of these three SNPs were analyzed and compared them with those of other reported populations. Haplotype frequencies were calculated using Golden Helix Tree software and Linkage disequilibrium was represented by D”.Results: ABCB1 C3435T allele frequencies for C allele and T allele were 0.57 and 0.43, respectively. For ABCB1 G2677T/A the allele frequencies for G allele, T allele, and A allele were 0.65, 0.32 and 0.0, respectively. As for ABCB C1236T, its allele frequencies were 0.65 for C allele and 0.35 for T allele. C1236T, G2677T/A, and C3435T SNPs were expected to be structured in 8 different haplotypes with GC- C (37.6.0 %), T-T-T (18.6 %), G-C-T (14.3 %) and T-T-C (12 %) that were most prominent. The haplotype frequency distribution of our study group was found to be significantly different from those of Chinese, Indian, Japanese, African and Caucasian (p < 0.0001) and resemble Ashkenazi Jewish and Slovenian populations (p > 0.05).Conclusion: In addition to earlier studies, the findings of the current study provide evidence that suggest the use of genetic polymorphisms of ABCB1 SNPs as markers for ethnicity and ancestral origin. The analysis of haplotype and genotype can be useful in identifying the relation between ABCB1 polymorphism, disease susceptibility and drug disposition.Keywords: Genotype, Allele, MDR1, ABCB1, Polymorphism, Haplotype frequencie
Food Safety Training: A Study of Food Handlers Working in Hotels in the North of Jordan
In spite of decenniums of advancement, a numerous foodborne outbreaks continue to occur each year; these were mostly happening due to malpractices of employees working in foodservices. This study aims to investigate the role of food safety training in improving food handlers' practices through the application of Knowledge, Attitude and Practices (KAP) model. Primary data were collected using a self-completed questionnaires that were collected from 100 Food and Beverage (F&B) employees working in hotels at the north of Jordan. Findings confirmed the role of food safety training in increasing F&B employees’ knowledge which positively correlates with their food handling practices. Furthermore, this study explored work environment elements affecting the transformation of learned knowledge into proper food handling practices; these include management motivation, availability of necessary resources and facilities and reinforcement programs. The study contributed to knowledge by employing the aforementioned variables to produce an adapted version of the KAP model
Adapting performance and emotional support feedback to cultural differences
This paper investigates adaptation of feedback to learners' cultural backgrounds. First, we investigate how to portray the cultural background of a learner. Second, we present a qualitative focus-group study, investigating how participants from different cultures believe culture affects the kind of feedback given to a learner. Finally, we present an empirical study on how humans adapt feedback based on the cultural background of learners to inspire an algorithm. Our investigations resulted in a set of stories which can be used to reliably portray a person's culture when investigating cultural adaptation in indirect experiments and user as wizard studies. They also provided insights into the adaptations people make to cultural differences
Sepsis outcomes in patients receiving statins prior to hospitalization for sepsis: comparison of in-hospital mortality rates between patients who received atorvastatin and those who received simvastatin
Design and characterization of a new hybrid peptide from LL-37 and BMAP-27
Yara Al Tall,1 Ahmad Abualhaijaa,1 Mohammad Alsaggar,1 Ammar Almaaytah,1 Majed Masadeh,1 Karem H Alzoubi21Department of Pharmaceutical Technology; 2Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, JordanBackground and purpose: The world is heading to a post-antibiotic era where the treatment of bacterial infections will not be possible even with well-known last-line antibiotics. Unfortunately, the emergence of multidrug resistant bacterial strains is uncontrollable, and the humanity will face a life-threatening fate unless new antimicrobial agents with new bacterial target sites are promptly developed. Herein, we design a hybrid antimicrobial peptide (B1) from helical parts taken from the parent peptides: LL-37 and BMAP-27. The purpose of this design is to improve the potency and enhance the toxicity profile of the parent peptides.Methods: Rational design was used to hybridize two antimicrobial peptides, in which two helical parts from the bovine analog BMAP-27, and the human cathelicidin LL-37 were used to generate a novel peptide (B1). The physicochemical properties were checked using in silico methods. The antimicrobial activities were tested against nine control and resistant strains of Gram-positive and Gram-negative bacteria. On the other hand, the antibiofilm activities were tested against four resistant strains. The cytotoxicity on mammalian cells was tested using HEK293, and the hemolysis activity was also investigated on human blood. Finally, synergistic studies were performed with four conventional antibiotics against four resistant strains of Gram-positive and Gram-negative bacteria.Results: The new peptide B1 exhibited broad-spectrum activities against all tested strains. The concentration against planktonic cells ranged between 10 and 20 μM. However, 40–60 μM were needed to eradicate the biofilms. B1 showed reduced toxicity toward mammalian cells with minimal hemolysis risk. On the other hand, the synergistic studies showed improved activities for the combined conventional antibiotics with a huge reduction in their minimum inhibitory concentration values. The concentrations of B1 peptide combined with the tested antibiotics were also decreased markedly down to 0.5 μM in some cases.Conclusion: B1 is a hybrid peptide from two cathelicidin peptides. It showed an improved activity compared to parent peptides. The hybridization was successful in this study. It generated a new potent broad-spectrum antimicrobial. The toxicity profile was improved, and the synergism with the convention antibiotics showed promising results.Keywords: antimicrobial peptides, rational design, hybridization, antimicrobial resistance, antibiofilm activity, synergis
Lograr la recuperación del servicio a través de la innovación del servicio: El papel crítico del empoderamiento del empleado
Research in service recovery and service innovation has
attracted significant attention in recent years but few studies
have focused on achieving service recovery through service
innovation. The current study aims to bridge this gap in
research – to investigate the effect of service innovation on
service recovery. Additional emphasis is also given to examining whether employee empowerment serves as a
mediator between service innovation and service recovery in
the hotel industry. A quantitative survey method was applied
by using a 60-item questionnaire and data collected from a
sample of 381 employees from five-star hotels in Jordan. The
findings confirmed the hypotheses, revealing a direct effect of
service innovation on employee empowerment which, in turn,
had a significant influence on service recovery. Additionally,
this study proposed a model of influence of service innovation
in service recovery, whereby employee empowerment fully
mediates this relationship. The current study contributes to the
existing literature on service innovation and service recovery
as it identifies the role of service innovation in enhancing
service recovery performance in hotelsLa investigación en recuperación de servicios e innovación de servicios ha atraído una atención significativa en los últimos años, pero pocos estudios se han centrado en lograr la recuperación de servicios a través de la innovación de servicios. El presente estudio tiene como objetivo cerrar esta brecha en la investigación, para investigar el efecto de la innovación de servicios en la recuperación de servicios. También se hace hincapié en examinar si el empoderamiento de los empleados sirve como mediador entre la innovación y la recuperación del servicio en la industria hotelera. Se aplicó un método de encuesta cuantitativa utilizando un cuestionario de 60 ítems y datos recopilados de una muestra de 381 empleados de hoteles de cinco estrellas en Jordania. Los hallazgos confirmaron las hipótesis, revelando un efecto directo de la innovación en el servicio sobre el empoderamiento de los empleados que, a su vez, tuvo una influencia significativa en la recuperación del servicio. Adicionalmente, este estudio propuso un modelo de influencia de la innovación en el servicio en la recuperación del servicio, en el que el empoderamiento de los empleados media plenamente en esta relación. El estudio actual contribuye a la literatura existente sobre innovación de servicios y recuperación de servicios, ya que identifica el papel de la innovación de servicios en la mejora del desempeño de recuperación de servicios en hotele
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