Seismic analysis of transmission tower under low to moderate earthquake loading

In Malaysia, even though the country can be considered as a low seismic area, the structural safety under seismic load has not been studied. Therefore, seismic vulnerability assessment is needed to be performed, especially for the towers. The objectives of this study are to investigate the capacity of tower members, failure mode, determine seismic capacity, and to derive seismic fragility curve for towers in Malaysia when subjected to far-field earthquake. The numerical models of three different heights towers were established in non-linear FE software, namely SAP2000. Equivalent static and response spectrum analysis, Pushover analysis and time history analysis were performed to determine the capacity of the towers members, capacity and fragility of towers, respectively. Totally, 6 far-field earthquake records, which were scaled from 0.05g up to 0.6g, were used in an incremental dynamic analysis in order to obtain fragility curves. Result from this study revealed that plastic hinge formation occurred near the tower base. Capacity curve was proved that the capacity of the studied tower decreases when the height of tower increases, as the length of tower member increases. The result of fragility curves showed that the most vulnerable tower due to far-field earthquake was tower with tallest (63.33m) height, and the probability of damage has significantly increased for the peak ground acceleration (PGA) larger than 0.2g

Challenges and Their Practices in Adoption of Hybrid Cloud Computing: An Analytical Hierarchy Approach

Cloud computing adoption provides various advantages for companies. In particular, hybrid cloud shares the advantages of both the public and private cloud technologies because it combines the private in-house cloud with the public on-demand cloud. In order to obtain benefits from the opportunities provided by the hybrid cloud, organizations want to adopt or develop novel capabilities. Maturity models have proved to be an exceptional and easily available method for evaluating and improving capabilities. However, there is a dire need for a robust framework that helps client organizations in the adoption and assessment of hybrid cloud. Therefore, this research paper aims to present a taxonomy of the challenging factors faced by client organizations in the adoption of hybrid cloud. Typically, such a taxonomy is presented on the basis of obtained results from the empirical analysis with the execution of analytical hierarchy process (AHP) method. From the review of literature and empirical study, in total 13 challenging factors are recognized and plotted into four groups: "Lack of Inclination,""Lack of Readiness,""Lack of Adoption,"and "Lack of Satisfaction."The AHP technique is executed to prioritize the identified factors and their groups. By this way, we found that "Lack of Adoption"and "Lack of Satisfaction"are the most significant groups from the identified challenging factors. Findings from AHP also show that "public cloud security concern"and "achieving QoS"are the upper ranking factors confronted in the adoption of hybrid cloud mechanism by client organizations because their global weight (0.201) is greater than those of all the other reported challenging factors. We also found out 46 practices to address the identified challenges. The taxonomy developed in this study offers a comprehensive structure for dealing with hybrid cloud computing issues, which is essential for the success and advancement of client and vendor organizations in hybrid cloud computing relationships.Qatar University Internal Grant No. IRCC-2021-010

A study of sharp coefficient bounds for a new subfamily of starlike functions

AbstractIn this article, by employing the hyperbolic tangent function tanhz, a subfamily$\mathcal{S}_{\tanh }^{\ast }$Stanh∗of starlike functions in the open unit disk$\mathbb{D}\subset \mathbb{C}$D⊂C:$$\begin{aligned} \mathbb{D}= \bigl\{ z:z\in \mathbb{C} \text{ and } \vert z \vert < 1 \bigr\} \end{aligned}$$D={z:z∈C and |z|<1}is introduced and investigated. The main contribution of this article includes derivations of sharp inequalities involving the Taylor–Maclaurin coefficients for functions belonging to the class$\mathcal{S}_{\tanh }^{\ast }$Stanh∗of starlike functions in$\mathbb{D}$D. In particular, the bounds of the first three Taylor–Maclaurin coefficients, the estimates of the Fekete–Szegö type functionals, and the estimates of the second- and third-order Hankel determinants are the main problems that are proposed to be studied here

Systematic Mapping Study on Security Approaches in Secure Software Engineering

In the modern digital era, software systems are extensively adapted and have become an integral component of human society. Such wide use of software systems consists of large and more critical data that inevitably needs to be secured. It is imperative to make sure that these software systems not only satisfy the users' needs or functional requirements, but it is equally important to make sure the security of these software systems. However, recent research shows that many software development methods do not explicitly include software security measures during software development as they move from demand engineering to their final losses. Integrating software security at each stage of the software development life cycle (SDLC) has become an urgent need. Tackling software security, various methods, techniques, and models have been suggested and developed, however, only a few of them provide strong evidence for building secure software applications. The main purpose of this research is to study security measures in the context of the development of secure software (SSD) during the study of systematic mapping (SMS). Based on the inclusion and exclusion criteria, 116 studies were selected. After the data extraction from the selected 116 papers, these were classified based on the quality assessment, software security method, SDLC phases, publication venue, and SWOT analysis. The results indicate that this domain is still immature and sufficient research work needs to be carried out particularly on empirically evaluated solutions.Qatar University [IRCC-2020-009]

Systematic Literature Review on Security Risks and its Practices in Secure Software Development

Security is one of the most critical aspects of software quality. Software security refers to the process of creating and developing software that assures the integrity, confidentiality, and availability of its code, data, and services. Software development organizations treat security as an afterthought issue, and as a result, they continue to face security threats. Incorporating security at any level of the Software Development Life Cycle (SDLC) has become an urgent requirement. Several methodologies, strategies, and models have been proposed and developed to address software security, but only a few of them give reliable evidence for creating secure software applications. Software security issues, on the other hand, have not been adequately addressed, and integrating security procedures into the SDLC remains a challenge. The major purpose of this paper is to learn about software security risks and practices so that secure software development methods can be better designed. A systematic literature review (SLR) was performed to classify important studies to achieve this goal. Based on the inclusion, exclusion, and quality assessment criteria, a total of 121 studies were chosen. This study identified 145 security risks and 424 best practices that help software development organizations to manage the security in each phase of the SDLC. To pursue secure SDLC, this study prescribed different security activities, which should be followed in each phase of the SDLC. Successful integration of these activities minimizing effort, time, and budget while delivering secure software applications. The findings of this study assist software development organizations in improving the security level of their software products and also enhancing their security efficiency. This will raise the developer's awareness of secure development practices as well

Line overload alleviations in wind energy integrated power systems using automatic generation control

Modern power systems are largely based on renewable energy sources, especially wind power. However, wind power, due to its intermittent nature and associated forecasting errors, requires an additional amount of balancing power provided through the automatic generation control (AGC) system. In normal operation, AGC dispatch is based on the fixed participation factor taking into account only the economic operation of generating units. However, large-scale injection of additional reserves results in large fluctuations of line power flows, which may overload the line and subsequently reduce the system security if AGC follows the fixed participation factor’s criteria. Therefore, to prevent the transmission line overloading, a dynamic dispatch strategy is required for the AGC system considering the capacities of the transmission lines along with the economic operation of generating units. This paper proposes a real-time dynamic AGC dispatch strategy, which protects the transmission line from overloading during the power dispatch process in an active power balancing operation. The proposed method optimizes the control of the AGC dispatch order to prevent power overflows in the transmission lines, which is achieved by considering how the output change of each generating unit affects the power flow in the associated bus system. Simulations are performed in Dig SILENT software by developing a 5 machine 8 bus Pakistan’s power system model integrating thermal power plant units, gas turbines, and wind power plant systems. Results show that the proposed AGC design efficiently avoids the transmission line congestions in highly wind-integrated power along with the economic operation of generating units

Integration of electric vehicles in smart grids : A review of the advantages and challenges of vehicle-to-grid technology

The term 'vehicle-to-grid (V2G)' refers to the ability of electric vehicles to supply or consume power from the grid. V2G implementation may provide reactive power support, load balancing, harmonic filtering, and even power grid breakdown recovery. In certain situations, these technologies may provide auxiliary functions, such as voltage and frequency control and transient stability. Aside from the grid services, EV owners may reap major financial advantages from employing V2G services. These include lower operating costs, no congestion charges, free parking, and higher resale value. However, it has implications for both grid operators and EV owners. Increased EV adoption may have a negative impact on power distribution network operations due to transformer, cable, and feeder overloading. To compensate for the overload, an extra generator will be needed, which will increase voltage deviations and current distortions. From the EV owners' standpoint, the cost of battery degradation and wear caused by frequent charging and discharging is the biggest concern. While V2G operation may reduce the lifespan of EVs, it is expected to be more cost-effective for EV owners and grid operators in the long term. Therefore, the purpose of this article is to examine and analyze the benefits, challenges, and technology of EVs in a V2G system

Antimicrobial, Antioxidant and Cytotoxic Potential of Aerial Parts of Monotheca buxifolia

In this study, different aerial parts of Monotheca Buxifolia were screened for their antibacterial, antifungal, and anti-oxidant activity. Extract of the fruit was most active against P. mirabilis, MSSA and M. morganii strains. Moreover, the methanolic fruit extract demonstrated good antibacterial properties against VRSA, S. aureus and Acinetobacter. Despite having good antibacterial properties, Monotheca buxifolia showed low antifungal activity. The cytotoxic activity was the highest in the pet-ether fruit extract, causing 60% of lethality against Artemia salina larvae with LD50 at 3.307. The highest scavenging activity was shown by the methanolic leaf extract in a concentration-dependent pattern. The findings of this study suggest that Monotheca Buxifolia has good antibacterial, antioxidant potential but low antifungal properties

Spatio-Statistical Analysis of Temperature and Trend Detection in Baluchistan, Pakistan

The assessment of temperature variability in any region of the world is important for prior planning in the context of current climate change. The mean monthly, seasonal and annual temperature data of nine meteorological stations was analysed in this study to determine the temperature variability and trend in Baluchistan province, Pakistan. The non-parametric Mann–Kendall and Sen’s slope estimator were applied to investigate the temperature trend pattern in the study Temperature data from the relevant meteorological stations (met-stations) were collected for this purpose from the Pakistan Meteorological Department and the National Center for Environmental Information. The result revealed an increasing significant trend (IST) in the mean annual temperature at Dalbandin, Kalat, Quetta, Zhob and Gawadar meteorological stations. While the seasonal minimum, maximum and mean temperature showed trend fluctuations in winter, spring and autumn seasons. In the seasonal analysis, the increasing trend has been detected in most of the meteorological stations (Dalbandin, Kalat, Quetta, Zhob, Khuzdar, Lasbella, Gawadar) in all four seasons. Whereas in Sibi met-station, a decreasing significant trend (DST) was recorded in summer (minimum, maximum and mean) and the met-station Barkhan recorded decreasing trend in maximum temperature in the autumn season. The Baluchistan province is totally spread over an arid and semiarid area of Pakistan where temperature fluctuations further aggravate the deprived agriculture and sparse natural vegetation