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The purpose of this paper is to present a new system frequency response model with participation of wind-hydro-thermal units to overcome frequency deviations.

The extracted minimum frequency equation is considered as a constraint in security-constrained unit commitment calculations. Because of high-order polynomials in the frequency transfer function and high degree of nonlinearity of minimum frequency constraint, Routh stability criterion method and piecewise linearization technique are used to reduce system order and linearize the system frequency response model, respectively.

The results of this paper indicate that by using this model, the hourly minimum frequency is improved and is kept within defined range.

This combined model can be used to evaluate the frequency of the power system following unexpected load increase or generation disturbances. It also can be used to investigate the system frequency performance and ensure power system security which are caused by peak load or loss of generation in presence of renewable energies.

This study aims to provide resiliency against earthquakes to the framework of an urban road network and to construct a comprehensive model with sufficient computational detail to assist metropolitan managers as a decision support tool in emergency situations via parametric analysis (model behaviour analysis with parameter changes) to quantify the consequences of decisions.

Performed stages are: developing existing resilience assessment frameworks for use against earthquakes in urban road networks, identifying earthquake scenarios and estimating the weight of components using AHP, including an example modelling of Tehran; and developing modelling software (using Matlab®).

This study produced a software that performs three-dimensional (3D) graphical modelling, resiliency index measurements and its parametric analyses for the road networks against earthquakes. Based on this model, a prioritized list of upgrades is also introduced. The developed tool also addresses issues regarding the allocation of limited resources between the network components.

Because of the novelty of the study, there is limited literature on this topic.

The developed model provides urban managers with a comprehensive list of upgrades and empowering them to graphically and numerically evaluate the resiliency changes as they alter the parameters of these measures and balance their decisions based on available funding.

In contrast to previous studies, this study has focused on all of these three keywords: resiliency, earthquake and road networks, and not only two of them.

The main purpose of this study is revival of vernacular architecture of Zegalli houses, which can be beneficial in several aspects of sustainable architecture, and therefore, its reuse in contemporary architecture can be strongly recommended. Zegalli houses, in northern Iran, are almost-entirely wooden vernacular houses, which beside to having several aspects of sustainable architecture, have shown good resistance against past earthquakes. Their relatively good seismic performance is mainly because of their specific timber foundation, which creates a kind of rocking/rolling isolation, as well as their light weight and diagonally braced stiff walls.

In this paper, first the architectural features of Zegalli houses, particularly energy efficiency, sustainability and eco-friendliness are described. Then, their structural system, focusing more on their foundation, is discussed. Finally, a simplified model of the house, developed in a powerful finite element analysis program, is introduced, and sample results of a series of time history analyses (THA), employing three-component accelerograms of three selected earthquakes, are presented.

Results of THA show that the rocking/rolling behavior of foundation timbers in various levels significantly reduces seismic response of the house, leading to its stability against earthquakes with peak ground acceleration up to 0.25 g.

Regarding the architectural and structural merits of Zegalli houses, they can be considered as sustainable vernacular architecture, and therefore, architects and civil and structural engineers are encouraged to reconsider the use of these houses, with some modifications, in future developments.

3D dynamics analysis of Shikilli foundations of Zegalli houses is done for the first time in this study.

Almost design code is required for repairability of the buildings after a major earthquake. One such idea is “directed-damage design” (DDD), which means guiding the damage to some pre-decided parts of the structural system. To use the DDD idea for creation of repairable buildings, in this study, a structural system with seesaw motion with respect to a central massive support has been considered for steel buildings with square plan, and the bottom ends of the all circumferential columns at the lowest story have been equipped with double-ADAS (DADAS) dampers, which dissipate a great portion of the seismic input energy. The purpose of this paper is to investigate the hysteretic behavior of DADAS dampers by using finite element analysis. At first, a set of regular steel multistory buildings with five stories have been designed based on the conventional code provisions. Then, the structures of the designed buildings have been changed into the structure with seesaw motion by using, at the base level of the building, a massive central column, eliminating other middle columns, and equipping circumferential columns with DADAS dampers.

For repairability buildings in the last three mentioned studies a set of orthogonal strong girders, in the form of grid, has been used. In the present study, the number of bays in the considered building is four in both directions. A major modification has been made in the yielding-plate energy dissipating elements of the circumferential columns, which makes their manufacturing and installation much practical as illustrated in the following sections of the paper.

In the proposed rocking structural system for regular multistory steel buildings, creation of the possibility of rocking motion has been done by using a space truss resting on a huge central hinge support at base level with a series of circumferential energy dissipating columns at that level.

One such idea is DDD idea, which means guiding the damage to some pre-decided parts of the structural system.

The purpose of this paper is to present an analytical calculation for estimating the leakages field distribution in surface-mounted permanent magnet synchronous motors (SMPMSMs) according to a sub-domain field model for eccentricity fault detection.

The magnetic field domain is classified into four sub-domains of PMs, air gap, stator core and outer region. In the proposed method, the governing equations taking the rotor eccentricity effect into account per region and the interface boundary conditions between sub-domains are formulated using the regular perturbation technique, Taylor series and Fourier series expansion. Maxwell's equations are solved in different regions in the polar coordinate system regarding the boundary conditions.

The radial and tangential components of electromagnetic field distribution in all sub-domains of one SMPMSM are obtained using the proposed method analytically. Finite element analysis is used to validate the results of the proposed method; the results indicated that the analytical model matches the finite-element prediction up to 30% eccentricity, except for some peak values that depend on the harmonic order value. The results of this paper demonstrated that in the event of eccentricity, an asymmetric magnetic field is generated in the outer region of the machine. Although its amplitude is small, it can be an indicator for detecting eccentricity faults from the outside environment of the machine.

The formulas presented in this paper can be applied as a new technique for detecting eccentricity faults in these motors from the outside environment.

This paper aims to introduce a new structure for coaxial magnetic gears.

The study discusses the design and electromagnetic modeling of a triple-speed coaxial magnetic gear (TSCMG) for three different levels of torques in special applications such as wind energy conversion and electrical vehicles. The proposed TSCMG consists of inner, middle and outer rotor, which has one rotor more than its conventional counterpart. The suggested TSCMG’s related equations such as transform ratio and torque are calculated, then TSCMG is simulated in a finite element environment. A comprehensive study has been done on TSCMG, and results are compared with two other magnetic gears with the same volume but two speeds.

The obtained results show that the proposed structure for TSCMGs is significantly practical and applicable in higher ranges of torques. Finally, an experimental TSCMG is prototyped to verify the results.

The achievements are excellent and confirm that TSCMG can be used as powerful equipment in a wide range of application like permanent wind turbines to generate electricity in 24 h per every single day.

The international energy agency states that the world’s primary energy needs are expected to grow to 55 per cent until 2030. Therefore, oil and gas industry as the main energy source will be more crucial where building or advancing new capacities is required. Because the reports highlight the delay as a recurring problem, thereby, more in-depth investigation to find out the main contributing causes is needed.

Root cause analysis (RCA) was applied to identify, rank, analysis and categorize the main sources of this problem.

Based on RCA procedure; Pareto analysis showed that 84.7 per cent of the delay is because: the radar chart indicated no difference in perception of the participants regarding the importance of the root causes, correlation analysis suggested strong relationship among the participants and the cause-and-effect diagram emphasized more on operational, human and equipment categories, which in total account for 51.86 per cent of the delay.

The risk planners of large-scale projects can consider these root causes as the main items to analysis, monitor and control, as they are vitally important for project success.

The purpose of this paper is to investigate the relationship between total quality management practices and the organizational performance in the Jordanian construction chemicals companies.

In this research, ten constructs were used to measure TQM practices, whereas six constructs were used to measure the organizational performance. A total of 160 questionnaires were distributed to 28 companies. Of these 131 questionnaires were completed and used for the analysis, representing a response rate of 81.9 percent.

Analysis has shown that TQM practices positively affect the organizational performance, with a significant value for top management commitment, customer focus, supplier management, process control and continuous improvement.

Results were based on perceptual data provided by participants working in different sectors of the organization, which may not provide a clear picture. It would be appropriate to consider collecting information from several stakeholders such as customers and suppliers. Willingness of respondents and delivering data within time were a big challenge though efforts were made to guarantee the confidentiality of the respondents.

Results from this research points out that TQM is considered as a key-contributing factor to firm’s survival. It also provides empirical support that TQM implementation in manufacturing organizations contributes to the performance and survival of such organizations. This research also provides an understanding of the dynamic role of TQM practices that would help managers pay attention to the fundamental practices that have a direct impact on the firms’ performance. This will help the organizations to dedicate efforts and allocate resources to get the best long-term outcomes and to figure out their strengths and weaknesses to develop and implement a new strategy to enhance their competitive position.

Construction sector in Jordan is a competitive sector. Therefore, quality in such industry is vital. Many companies in Jordan have much interest in implementing TQM practices. However, research efforts related to this field are rare. No research papers investigating the relationship between TQM practices and performance in Jordanian construction chemicals companies have been found. This research, therefore, seeks to examine the relationship between TQM practices and the construction chemicals firms’ performance in Jordan.

This paper aims to highlight the crucial role of decision makers and emergency managers in reducing the unpleasant consequences of disasters.

An attempt has been made to clarify the measures for planning and implementation of training issues in earthquake emergency response for the emergency managers as an essential part at various managerial levels.

The paper reveals that, although the high‐level managers such as ministers are authoritative bodies for managing the routine problems of the country, in situations such as a “major emergency”, specific knowledge and experience of emergency issues are required for the emergency management to be successful. It also explores the ways and opportunities for achieving successful training programmes for the emergency managers.

The existing challenges, including the lack of adequate background knowledge and experience in emergency management, insufficient time to train, the inadequacy of the required technical supporting tools, and other related issues, emerge, which need to be identified.

The research can be practically useful for emergency managers who are involved in response activities in disasters by providing suitable and appropriate recommendations for efficient training.

There are only a few works on training of earthquake emergency managers, especially in developing countries such as Iran.

The purpose of this paper is to identify and discuss the main prerequisites which are deemed for successful disaster mitigation activities in megacities by considering various aspects related to disaster risk reduction.

The paper provides a general background with regard to the social and cultural patterns for involving local people to participate in the activities related to awareness raising before, and saving their lives and properties after the earthquakes. It then defines what is required for preparing disaster scenarios.

Prerequisites of comprehensive response plans, to be used in the aftermath of earthquakes in large cities, are discussed.

There is a lack of complete information, with regard to various social, and cultural aspects of disaster mitigation, in developing countries, such as Iran.

By following the steps mentioned and discussed in the paper for disaster mitigation planning and applying the proposed measures, the neighbourhoods in megacities can define and manage the activities better – which is crucial for saving lives in the aftermath of large earthquakes.

The paper details the requirements that are necessary for successful disaster mitigation activities in large cities and the difficulties and challenges which can be faced in encountering them.