Structure's base design for earthquake protection numerical and experimental study

Alsaif, K.,Kaplan, H. Techno-Press 2003 Structural Engineering and Mechanics, An Int'l Jou Vol.16 No.1

A base isolation system is proposed for earthquake protection of structures. The system incorporates spherical supports for the base, a specially designed spring-cam system to keep the base rigidly supported under normal condition and to allow it to move for the duration of the earthquake under the constraint of a spring with optimized non-linear characteristics. A single-story model is constructed to investigate the feasibility of the concept. Numerical simulations of the system as well as experimental results show that 95% reduction of the transmitted force to the structure can be achieved. To demonstrate the effectiveness of this isolation mechanism, the maximum dynamic bending stress developed at predetermined critical points within the frame of the structure is measured. Significant reduction of the dynamic stresses is obtained.

Structure's base design for earthequake protection numerical and experimental study

K.Alsaif,H.Kaplan 국제구조공학회 2003 Structural Engineering and Mechanics, An Int'l Jou Vol.16 No.1

Does the quality of orthodontic studies influence their Altmetric Attention Score?

Thamer Alsaif,Nikolaos Pandis,Martyn T. Cobourne,Jadbinder Seehra 대한치과교정학회 2023 대한치과교정학회지 Vol.53 No.5

Objective: The aim of this study was to determine whether an association between study quality, other study characteristics, and Altmetric Attention Scores (AASs) existed in orthodontic studies. Methods: The Scopus database was searched to identify orthodontic studies published between January 1, 2017, and December 31, 2019. Articles that satisfied the eligibility criteria were included in this study. Study characteristics, including study quality were extracted and entered into a pre-pilot data collection sheet. Descriptive statistics were calculated. On an exploratory basis, random forest and gradient boosting machine learning algorithms were used to examine the influence of article characteristics on AAS. Results: In total, 586 studies with an AAS were analyzed. Overall, the mean AAS of the samples was 5. Twitter was the most popular social media platform for publicizing studies, accounting for 53.7%. In terms of study quality, only 19.1% of the studies were rated as having a high level of quality, with 41.8% of the studies deemed moderate quality. The type of social media platform, number of citations, impact factor, and study type were among the most influential characteristics of AAS in both models. In contrast, study quality was one of the least influential characteristics on the AAS. Conclusions: Social media platforms contributed the most to the AAS for orthodontic studies, whereas study quality had little impact on the AAS.

Eye Blink Detection and Alarm System to Reduce Symptoms of Computer Vision Syndrome

Atheer K. Alsaif,Abdul Rauf Baig International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.5

In recent years, and with the increased adoption of digital transformation and spending long hours in front of these devices, clinicians have observed that the prolonged use of visual display units (VDUs) can result in a certain symptom complex, which has been defined as computer vision syndrome (CVS). This syndrome has been affected by many causes, such as light refractive errors, poor computer design, workplace ergonomics, and a highly demanding visual task. This research focuses on eliminating one of CVSs, which is the eye dry syndrome caused by infrequent eye blink rate while using a smart device for a long time. This research attempt to find a limitation on the current tools. In addition, exploring the other use cases to utilize the solution based on each vertical and needs.

Synthesis, structural characterization, and optical properties of PVA/MnO2 materials for optoelectronics applications

Norah A. M. Alsaif,A. Atta,E. Abdeltwab,M. M. Abdel‑Hamid 한국고분자학회 2024 Macromolecular Research Vol.32 No.1

In this study, polyvinyl alcohol (PVA) was mixed with concentration of 5%, 7.5%, and 10% of manganese dioxide ( MnO2) to form PVA/MnO2 films using solution cast approach method. The X-ray diffraction (XRD) verified that the nanomaterials films were successfully fabricated. The scanning electron microscope (SEM) illustrates the uniform MnO2 dispersion within the PVA host matrix. Additionally, the influence of MnO2 on the optical properties is recorded. The refractive index (n0) is improved by adding MnO2, from 1.29 for PVA to 1.87 for PVA/5%MnO2 and 2.86 for PVA/10%MnO2. The PVA had a dispersion energy of 2.53 eV, while PVA with 5% MnO2 had 4.86 eV, PVA with 7.5% MnO2 had 5.74 eV, and PVA with 10%MnO2 had 7.12 eV. In addition, the oscillation energy E0 decreased from 3.79 for PVA to 1.94, 1.72, and 0.99 eV, respectively for PVA/5%MnO2, PVA/7.5%MnO2, and PVA/10%MnO2. It is evident from the data that the incorporation of MnO2 to the PVA polymer alters its optical properties. This proved the existence of strong interactions of PVA and MnO2 due to the modification of the PVA/MnO2 electronic structure. Moreover, the plasma frequency W p value increased from 0.79 × 1013 s− 1 for PVA to 2.06 × 1013 s− 1 for PVA/10%MnO2. These shifts in W p provided the polarization is modified for the PVA/MnO2. The results obtained in this study provide evidence of the advantages associated with the utilization of MnO2 nanoparticles as a filler of improved polymeric structures. These findings also propose the potential suitability of MnO2 nanoparticles for application in the field of optics and electronic devices.

Lack of Association of BRCA1 and BRCA2 Variants with Breast Cancer in an Ethnic Population of Saudi Arabia, an Emerging High-Risk Area

Hasan, Tarique Noorul,Shafi, Gowhar,Syed, Naveed Ahmed,Alsaif, Mohammed Abdullah,Alsaif, Abdulaziz Abdullah,Alshatwi, Ali Abdullah Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Incidence of breast cancer shows geographical variation, even within areas of ethnic homogeneity. Saudi Arabia has witnessed an increase in occurrence of breast cancer in its unexplored ethnic populations over the past few years. We aimed at determining whether any association exists between single nucleotide polymorphisms in breast cancer associated gene 1 (BRCA1) and breast cancer associated gene 2 (BRCA2) and the risk of breast cancer. TaqMan based Real Time Polymerase chain reaction genotyping assays were used to determine the frequency of single nucleotide polymorphisms in BRCA1 (rs799917) and BRCA2 (rs144848) in a group of 100 breast cancer patients and unaffected age matched controls of Saudi Arabian origin. The present data revealed that neither BRCA1 nor the BRCA2 studied variant show any significant association with the disease. This study failed to find any role of the concerned variants in breast cancer either as risk or as prognostic factors. The small number of patients registered was one of the limitations of this study. In summary, comparison of mutation profile with other ethnic populations and regions reflected both differences and similarities indicating co-exposure to a unique set of risk factors. The differences could be due to exposure to particular environmental carcinogens; different lifestyle, reproductive pattern; dietary or cultural practices of Saudi Arabian women that need further investigations.

Vibration mitigation of composite laminated satellite solar panels using distributed piezoelectric patches

Foda, M.A.,Alsaif, K.A. Techno-Press 2012 Smart Structures and Systems, An International Jou Vol.10 No.2

Satellites with flexible lightweight solar panels are sensitive to vibration that is caused by internal actuators such as reaction or momentum wheels which are used to control the attitude of the satellite. Any infinitesimal amount of unbalance in the reaction wheels rotors will impose a harmonic excitation which may interact with the solar panels structure. Therefore, quenching the solar panel's vibration is of a practical importance. In the present work, the panels are modeled as laminated composite beam using first-order shear deformation laminated plate theory which accounts for rotational inertia as well as shear deformation effects. The vibration suppression is achieved by bonding patches of piezoelectric material with suitable dimensions at selected locations along the panel. These patches are actuated by driving control voltages. The governing equations for the system are formulated and the dynamic Green's functions are used to present an exact yet simple solution for the problem. A guide lines is proposed for determining the values of the driving voltage in order to suppress the induced vibration.

Vibration mitigation of composite laminated satellite solar panels using distributed piezoelectric patches

M.A. Foda,K.A. Alsaif 국제구조공학회 2012 Smart Structures and Systems, An International Jou Vol.10 No.2

Satellites with flexible lightweight solar panels are sensitive to vibration that is caused by internal actuators such as reaction or momentum wheels which are used to control the attitude of the satellite. Any infinitesimal amount of unbalance in the reaction wheels rotors will impose a harmonic excitation which may interact with the solar panels structure. Therefore, quenching the solar panel’s vibration is of a practical importance. In the present work, the panels are modeled as laminated composite beam using first-order shear deformation laminated plate theory which accounts for rotational inertia as well as shear deformation effects. The vibration suppression is achieved by bonding patches of piezoelectric material with suitable dimensions at selected locations along the panel. These patches are actuated by driving control voltages. The governing equations for the system are formulated and the dynamic Green’s functions are used to present an exact yet simple solution for the problem. A guide lines is proposed for determining the values of the driving voltage in order to suppress the induced vibration.

Network Forensics and Intrusion Detection in MQTT-Based Smart Homes

Lama AlNabulsi,Sireen AlGhamdi,Ghala AlMuhawis,Ghada AlSaif,Fouz AlKhaldi,Maryam AlDossary,Hussian AlAttas,Abdullah AlMuhaideb International Journal of Computer ScienceNetwork S 2023 International journal of computer science and netw Vol.23 No.4

The emergence of Internet of Things (IoT) into our daily lives has grown rapidly. It's been integrated to our homes, cars, and cities, increasing the intelligence of devices involved in communications. Enormous amount of data is exchanged over smart devices through the internet, which raises security concerns in regards of privacy evasion. This paper is focused on the forensics and intrusion detection on one of the most common protocols in IoT environments, especially smart home environments, which is the Message Queuing Telemetry Transport (MQTT) protocol. The paper covers general IoT infrastructure, MQTT protocol and attacks conducted on it, and multiple network forensics frameworks in smart homes. Furthermore, a machine learning model is developed and tested to detect several types of attacks in an IoT network. A forensics tool (MQTTracker) is proposed to contribute to the investigation of MQTT protocol in order to provide a safer technological future in the warmth of people's homes. The MQTT-IOT-IDS2020 dataset is used to train the machine learning model. In addition, different attack detection algorithms are compared to ensure the suitable algorithm is chosen to perform accurate classification of attacks within MQTT traffic.

b-Sitosterol Prevents Lipid Peroxidation and Improves Antioxidant Status and Histoarchitecture in Rats with 1,2-Dimethylhydrazine-Induced Colon Cancer

Arul Albert Baskar,Khalid S. Al Numair,Micheal Gabriel Paulraj,Mohammed A. Alsaif,May Al Muamar,Savarimuthu Ignacimuthu 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.4

Oxidative stress has become widely viewed as an underlying condition in diseases such as ischemia/reperfusion disorders, central nervous system disorders, cardiovascular disease, cancer, diabetes, etc. The role that antioxidants play in the process of carcinogenesis has recently gained considerable attention. b-Sitosterol, a naturally occurring sterol molecule, is a relatively mild to moderate antioxidant and exerts beneficial effects in vitro by decreasing the level of reactive oxygen species. The present study evaluated the antioxidant potential of b-sitosterol in 1,2-dimethylhydrazine (DMH)-induced colon carcinogenesis. The enzymatic and nonenzymatic antioxidants and lipid peroxides in colonic and hepatic tissues were evaluated. Generation of reactive oxygen species, beyond the body’s endogenous antioxidant capacity, causes a severe imbalance of cellular antioxidant defense mechanisms. Elevated levels of liver lipid peroxides by DMH induction were effectively decreased by b-sitosterol supplementation. b-Sitosterol also exhibited a protective action against DMH-induced depletion of antioxidants such as catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione Stransferase,and reduced glutathione in colonic and hepatic tissues of experimental animals. Supplementation with b-sitosterol restored the levels of nonenzymatic antioxidants (vitamin C, vitamin E, and glutathione). Histopathological alterations in DMH-induced animals were restored to near normal in rats treated with b-sitosterol. Thus, b-sitosterol by virtue of its antioxidant potential may be used as an effective agent to reduce DMH-induced oxidative stress in Wistar rats and may be an effective chemopreventive drug for colon carcinogenesis.