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Comparisons between CRM and CCM PFC

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Energy and Power Engineering 2013年第4期5卷 864-868页

作者： Weiping Zhang Wei Zhang Jianbo Yang faris Al-Naemi Lab of Green Power & Energy System (GPES) North China University of Technology (NCUT) Beijing China Materials and Engineering Research Institute (MERI) Sheffield Hallam University (SHU) Sheffield UK

The paper presents detailed comparisons between CRM (critical conduction mode) and CCM (continuous conduction mode) control schemes used for Boost PFC converter. The two schemes are analyzed and compared under the chips of L6561 and UC 3854 which are commonly used for CRM and CCM respectively. Both schemes are based on multiplier;however, the CCM is more complex and needs more periphery components which increase the cost. The Boost PFC under CRM is easier to be implemented. Nevertheless, the variable switch frequency makes the system (including the power-stage inductor and capacitor) hard to design. It seems that the CRM PFC is more attractive in low power applications which only need to meet IEC61000-3-2 D standard. Some experiment results are also presented for the comparison.

关键词： CRM CCM PFC Boost

Impact of Internet Advertisement and Its Features on E-Commerce Retail Sales: Evidence from Europe

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Journal of Software Engineering and Applications 2013年第11期6卷 564-570页

作者： Osama Harfoushi Bader Alfawwaz Bader Obeidat Ruba Obiedat Hossam faris Department of Business Administration The University of Jordan Amman Jordan Department of Business Information Technology The University of Jordan Amman Jordan Department of Computer Information System Al-albayt University Mafraq Jordan

The stimulus to carry out this research is to investigate the relationship between internet advertisement and its features on the total E-commerce sales of the top five countries of Europe. The units of analysis are the individuals of UK, France, Italy, Germany and Netherland. Secondary data are collected from the reports of [1] (ADEX, 2010) and [2] (Eurostats, 2011). To empirically determine the relationship between independent variable and dependent variable in the European context, the study uses various statistical techniques, including OLS regression and correlation analysis techniques. The empirical findings indicate that the Internet advertisement features of search advertisement and classified advertisement have positive significant relationship with the E-commerce sales in Europe. The empirical findings indicate negative significant relationship of display advertisement with the E-commerce sales in Europe. However, this variable is also justified with the help of literature. Findings also demonstrate that search advertisement has strong positive relationship and it generates positive influence for the E-commerce sales as compared to the classified advertisement and display advertisement. Firms and marketers which are investing in online advertisement will find these results useful as they can get better sales and can use these features of online advertisement in order to maximize the sales of their products and services.

关键词： Features of Internet Advertisement Display Advertisement Search Advertisement Classified Advertisement E-Commerce Sales E-Commerce Sale in Europe

Evaluation of thalamus echogenicity by ultrasound as a marker of fetal lung maturity

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Open Journal of Obstetrics and Gynecology 2012年第3期2卷 270-275页

作者： faris A. Rasheed Zahraa’ M. Al-Sattam Saad A. Hussain Department of Obstetrics and Gynecology Al-Kindi Medical College University of Baghdad Baghdad Iraq Department of Obstetrics Al-Elwiya Maternity Teaching Hospital Baghdad Iraq Department of Pharmacology and Toxicology College of Pharmacy University of Baghdad Baghdad Iraq

The present study evaluated fetal thalamic echogenicity by ultrasound as a possible marker of fetal lung maturity in comparison with other ultrasound makers. A prospective longitudinal study performed in Al-Elwiya Maternity Teaching Hospital in Baghdad, Iraq during the period from April 2010 to March 2011. One hundred and forty two pregnant women (36 to 42 weeks of gestation) who were admitted for elective cesarean section and referred for an obstetric ultrasound scan at the same day of their elective cesarean section were included. Scanning with linear ultrasound with convex transducer frequency of 3.5 MHz was utilized to measure the biparietal diameter and the state of echogenicity was recorded as echogenic or echolucent, in addition to amniotic fluid vernix and the placental changes. The presence of echogenic thalamus as a sign of fetal lung maturity had a specificity of 86.53% which is higher than the three other signs of lung maturity;the positive predictive value was (89.6%) which is also higher than the three other signs, but the sensitivity was 63.33% and negative predictive value was 57.69% which is lower than the presence of vernix in the amniotic fluid, 86.66 and 67.56 respectively. In conclusion, evaluation of echogenic thalamus is beneficial, and can be considered as a new marker of fetal lung maturity;however, further studies are required to strengthen such idea.

关键词： Fetal Lung Maturity Thalamic Echogenicity Uultrasound

Design and Construction of Hot Wire-Probe Beam Displacement for Measurement Thermal Conductivity and Thermal Diffusivity of Chromium （Cr） Nanofluid in Distilled Water

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材料科学与工程（中英文B版） 2011年第1期1卷 22-27页

作者： faris Mohammed Ali W. Mahmood Mat Yunus Zainal Abidin Talib Department of Physics Faculty of Science University Putra Malaysia 43400 UPM Serdang Selangor Malaysia

This paper presents a new result of the thermal conductivity and thermal diffusivity of chromium (Cr) nanoparticle suspended in distilled water at different concentration of nanoparticles. All samples have been prepared using single step method. The thermal conductivity and thermal diffusivity were measured via hot wire-laser beam displacement technique. A numerical model of the heat conduction equation and probe beam deflection has been performed to determine the effective thermal conductivity and effective thermal diffusivity of chromium nanofluids. By fitting the experimental data to the numerical model, the thermal conductivity and thermal diffusivity of chromium nanofluid were obtained. The results show that the effective thermal conductivity and thermal diffusivity of chromium nanofluids increases with increasing of nanoparticles concentration in base fluid.

关键词：纳米流体位移测量热扩散蒸馏水热导率热线探针 Cr 铬

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冰雪消融日格陵兰岛转运时？

商业周刊（中文版） 2014年第11期 54-58,60页

作者： STEPHAN faris

现年49岁的农场主索福斯·弗雷德里克森（Sofus Frederiksen）住在格陵兰峡湾外延地带上方的一个小河谷里，每年冬天，这里巨大的浮冰都会融合成淡蓝色冰盖。拥有丹麦和因组特人血统的弗雷德里克森住在自建的房子里，他家养了10匹马、9... 详细信息

现年49岁的农场主索福斯·弗雷德里克森（Sofus Frederiksen）住在格陵兰峡湾外延地带上方的一个小河谷里，每年冬天，这里巨大的浮冰都会融合成淡蓝色冰盖。拥有丹麦和因组特人血统的弗雷德里克森住在自建的房子里，他家养了10匹马、95头牛和约500只羊，他的农场是纳萨克小镇上经营得最好的产业之一。

关键词：格陵兰岛冰雪转运德里克农场主

Improving Knowledge Based Spam Detection Methods: The Effect of Malicious Related Features in Imbalance Data Distribution

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International Journal of Communications, Network and System Sciences 2015年第5期8卷 118-129页

作者： Jafar Alqatawna Hossam faris Khalid Jaradat Malek Al-Zewairi Omar Adwan King Abdullah II School for Information Technology The University of Jordan Amman Jordan

Spam is no longer just commercial unsolicited email messages that waste our time, it consumes network traffic and mail servers’ storage. Furthermore, spam has become a major component of several attack vectors including attacks such as phishing, cross-site scripting, cross-site request forgery and malware infection. Statistics show that the amount of spam containing malicious contents increased compared to the one advertising legitimate products and services. In this paper, the issue of spam detection is investigated with the aim to develop an efficient method to identify spam email based on the analysis of the content of email messages. We identify a set of features that have a considerable number of malicious related features. Our goal is to study the effect of these features in helping the classical classifiers in identifying spam emails. To make the problem more challenging, we developed spam classification models based on imbalanced data where spam emails form the rare class with only 16.5% of the total emails. Different metrics were utilized in the evaluation of the developed models. Results show noticeable improvement of spam classification models when trained by dataset that includes malicious related features.

关键词： Spam E-Mail Malicious Spam Spam Detection Spam Features Security Mechanism Data Mining

Composition and Molecular Weight Distribution of Albumin and Globulin Protein Isolates from Durum Wheat Genotypes

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American Journal of Plant Sciences 2020年第2期11卷 137-147页

作者： Daniel Hailegiorgis Fikru Mekonnen faris Hailu Chong Ae Lee Song Joong Yun Department of Plant Science Wollo University Dessie Ethiopia Department of Biology Wollo University Dessie Ethiopia Institute of Agricultural and Life Sciences Jeonbuk National University Jeonju Republic of Korea Department of Crop Science and Biotechnology Jeonbuk National University Jeonju Republic of Korea

This paper attempts to evaluate the banding patterns of non-gluten protein isolates from the grain of durum wheat varieties. Under reduced condition, polyacrylamide-gel electrophoresis has revealed a number of different sized albumin and globulin protein bands. The electrophoretic pattern of globulin showed more polymorphisms than that of albumin. High polymorphism, both in band intensity and occurrence, was observed between 15 kDa and 35 kDa. Most of the protein bands were scored in the range of 10 kDa and 85 kDa in the two protein fractions. At a cutoff point 2.5, cluster analysis based on the SDS-PAGE of globulin proteins classified the durum wheat varieties into three major family groups. Generally, the experiment showed the suitability and usefulness of globulin protein fractions as a genetic marker in discriminating durum wheat genotypes.

关键词： Albumin Durum Wheat Globulin Polymorphism Seed Protein

Optimizing Software Effort Estimation Models Using Firefly Algorithm

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Journal of Software Engineering and Applications 2015年第3期8卷 133-142页

作者： Nazeeh Ghatasheh Hossam faris Ibrahim Aljarah Rizik M. H. Al-Sayyed Department of Business Information Technology The University of Jordan Aqaba Jordan Department of Business Information Technology The University of Jordan Amman Jordan

Software development effort estimation is considered a fundamental task for software development life cycle as well as for managing project cost, time and quality. Therefore, accurate estimation is a substantial factor in projects success and reducing the risks. In recent years, software effort estimation has received a considerable amount of attention from researchers?and became a challenge for software industry. In the last two decades, many researchers and practitioners proposed statistical and machine learning-based models for software effort estimation. In this work, Firefly Algorithm is proposed as a metaheuristic optimization method for optimizing the parameters of three COCOMO-based models. These models include the basic COCOMO model and other two models proposed in the literature as extensions of the basic COCOMO model. The developed estimation models are evaluated using different evaluation metrics. Experimental results show high accuracy and significant error minimization of Firefly Algorithm over other metaheuristic optimization algorithms including Genetic Algorithms and Particle Swarm Optimization.

关键词： Software Quality Effort Estimation Metaheuristic Optimization Firefly Algorithm

The Association between Dry Eye Disease and Depression, Anxiety, and Stress among Saudi Arabian Adults

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Open Journal of Ophthalmology 2021年第4期11卷 266-281页

作者： Danah Alrajhi Rahaf Almutairi Basma Alturki Atheer Almutairi faris Binyousef Shahad Alruwaili Dalal Alessa College of Medicine Imam Mohammad Lbn Saud Islamic University Riyadh Saudi Arabia Unaizah College of Medicine Qassim University Buraydah Saudi Arabia Ophthalmology Department College of Medicine Imam Mohammad Lbn Saud Islamic University Riyadh Saudi Arabia

Background: Dry eye disease (DED) is a multifactorial chronic ophthalmic disease. Its symptoms include blurry vision, foreign body sensation, pain, grittiness, ocular dryness and discomfort. Multiple studies have revealed that DED has a negative impact on patients’ quality of life, as well as their physical and mental health. In line with such findings, other research projects have indicated that depression, anxiety and stress share common risk factors associated with DED. Objective: We aimed to investigate the association between DED and depression, anxiety and stress among Saudi Arabian adults. Methods: This is a cross-sectional study conducted on 335 Saudi Arabian patients aimed to assess the prevalence of DED among individuals with depression, anxiety and stress. Data were collected using a self-administered questionnaire with the Depression Anxiety Stress Scales-21 (DASS-21) to assess the severity of stress, depression and anxiety, and the Ocular Surface Disease Index (OSDI) to assess DED symptoms. Results: The final number of participants was 448. Furthermore, 72.3% of them were aged 18 - 30 years, and 69.6% of them were females. The prevalence of depression, anxiety, and stress among patients with DED was 62.1%, 66.1%, 54%, and 77.9% respectively. Furthermore, we found that there were no significant differences between participants regarding the severity of DED based on different age groups (P = 0.889). Females with depression, anxiety, and stress, on the other hand, were significantly more likely to have severe DED than males with similar conditions. Conclusions: We confirmed a high prevalence of depression, anxiety, stress and DED in Saudi Arabian patients. There was a significant correlation between the four studied variables in which the greatest correlation was between anxiety and DED.

关键词： Anxiety Depression Dry Eye Disease Saudi Arabia