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With the rising concerns about climate change and technological developments, the deployment of low carbon technologies (LCT) is gaining importance for reliable and sustainable power system operation. To decarbonize the heat and transportation sectors, LCTs such as heat pumps (HP) and electric vehicles (EV) are integrated into the power system from the low voltage (LV) distribution network, where predominantly end-users are connected. However, the increasing penetration of EVs and HPs, together with distributed photovoltaic (PV) systems on the demand side, can cause technical challenges in LV distribution networks, such as under/over voltages at the far end of the feeders. Therefore, the hosting capacity of a grid for LCTs is limited due to network constraints such as line ampacity, bus voltage, and frequency. In this paper, voltage-constrained management approaches for LCTs are proposed to improve the grid hosting capacity in a real large-scale distribution network. Moreover, HPs, PVs, battery energy storage systems (BESS), and EVs as well as their vehicle-to-grid (V2G) feature are evaluated as LCTs. The uncertain behavior of these technologies is taken into consideration for more realistic analyses. In addition, the charging and discharging interactions of BESSs are controlled by following the power consumption profiles from the economic point of view. Furthermore, the hourly carbon data is used to control BESSs from an emission-sensitive aspect. To demonstrate the effectiveness of the proposed algorithms, a series of tests is conducted on a real distribution network model. The results show that the hosting capacity of the considered LV network can be increased from 35% to 50% using the proposed algorithms. The promising results obtained in this study pave the way for future active LCT management studies to improve hosting capacity in urban networks, and pilot demonstrations in the field.

The distribution system is demanded to be more efficient, more flexible and more intelligent due to the continued growth of the electricity loads, the high efficiency of energy utilization and the environmental protection. The traditional distribution systems are facing the challenge of evolving from passive networks to the active distribution networks (ADN) with the integration of multiple controllable resources. This paper presents an optimal operation and schedule model of the ADN, considering a variety of controllable resources such as distributed generations, battery storages and interruptible loads. To solve the optimization problem, a modified fuzzy adaptive PSO assisted by Kriging model (KMA-MFAPSO) is developed in this paper. In KMA-MFPSO, a novel constraint handling technique (CHT) based on the PSO is proposed to handle the constraints effectively. In addition, under the premise of ensuring the accuracy of the calculation, the Kriging model is used in KMA-MFAPSO to calculate the power flow the ADN approximately, which greatly speeds up the solving process. Finally, the effectiveness of the proposed algorithm is tested on a modified IEEE-123 system. The optimal results obtained by the proposed method are compared with the results obtained by using other solving algorithms. The simulation results indicate that KMA-MFAPSO is very robust and fast to solve the optimization problem so that it can be used in practical systems.

The European normatives prescribe content of 200 mg/Nm(3) NO for pulverized coal combusting power plants. In order to reduce content of NOx in Serbian thermal power plant (TPP) square Kostolac B square its necessary to implement particular measures until 2016. The mathematical model of lignite combustion in the steam boiler furnace is defined and applied to analyze the possibility of implementing certain primary measures for reducing nitrogen oxides and their effects on the steam boiler operation. This model includes processes in the coal-fired furnace and defines radiating reactive two-phase turbulent flow. The model of turbulent flow also contains sub-model of fuel and thermal NOx formation and destruction. This complex mathematical model is related to thermal and aerodynamic calculations of the steam boiler within a unified calculation system in order to analyze the steam boiler overall work. This system provides calculations with a number of influential parameters. The steam boiler calculations for unit 1 (350 MWe) of TPP square Kostolac B square are implemented for existing and modified combustion system in order to achieve effective, reliable and ecological facility work. The paper presents the influence analysis of large number of parameters on the steam boiler operation with an accepted concept of primary measures. Presented system of calculations is verified against measurements in TPP square Kostolac B square. (C) 2015 Elsevier Ltd. All rights reserved.

Propeller research has generally been focussed on improving the open water efficiency, and by considering the various energy losses associated with the marine screw propeller, it can be seen that for a design brief with given main engine power and RPM input, plus a thrust requirement defined by the specified ship speed, the most fruitful area for improvement in efficiency by propeller design is a reduction in energy losses. The simple way to increase the efficiency is reduction of blade area, increasing load near the tip and adopting a larger diameter with low RPM. However, vibration and noise will be the first issues when a designer tries to increase the efficiency of the propeller by these ways. This paper will present a simple prediction method of pressure fluctuations induced by thickness, propeller loading and unsteady cavitation taking not only propeller dimensions but also stern shape into account at the beginning of the propeller design.

Combustion turbines and combined cycles have become a dominant mode of new capacity addition in most parts of the world. However, to maximize the benefits of a combined cycle, it must be designed to take into account site-specific technical, economic, and environmental considerations. This paper outlines the important design considerations that must be addressed in the early stages of a project's development.

Mode Group Diversity Multiplexing (MGDM) aims at creating independent and parallel communication channels over a single Multimode Fiber (MMF) by exciting several groups of modes. It can significantly improve the capacity of short-reach Multimode Fiber networks. One of the key techniques involves demultiplexing the mixed signals from the output. In this paper, we proposed a fast independent component analysis (FastICA) algorithm to demultiplex the output signals of a 2 × 2 MGDM system more efficiently. The performance of this algorithm is evaluated and compared with the zero-forcing method. Our results indicate that FastICA can demultiplex the mixed signals, improve the eye opening of the eye diagram and achieve the similar results as zero-forcing method.

Japan Aerospace Exploration Agency (JAXA) developed the optical inter-orbit communications engineering test satellite (OICETS), which has a laser communications terminal called the laser utilizing communications equipment (LUCE). On August 23, 2005, OICETS was successfully launched and injected into a sun synchronous orbit at the altitude of 610 km. OICETS planned to demonstrate the free-space inter-orbit laser communications with the cooperation of the advanced relay and technology mission satellite (ARTEMIS) developed by the European Space Agency (ESA). On December 9, 2005, JAXA and ESA succeeded in a bidirectional optical inter-orbit communications experiment using a laser beam between OICETS and ARTEMIS. This is the world first bidirectional optical inter-orbit communication successfully established. This paper will describe the outline of OICETS satellite system and LUCE, the result of initial functional verifications on-orbit, the results of inter-orbit communications experiment between OICETS and ARTEMIS, and between OICETS and the ground station.

Tire shreds have gained wide acceptance as an engineered fill in the last two decades. Ladder-type metal reinforcement can be used to reinforce MSE walls with tire shred-sand mixtures as a backfill material. This paper reports the results of laboratory pullout testing performed on ladder-type metal reinforcement embedded in tire shred-sand mixtures. The ladder-type metal reinforcement consists of two parallel longitudinal steel bars welded to a series of cross bars forming rectangular apertures. Mixtures of Ottawa sand with 50–100 mm size tire shreds were prepared at different mixing ratios (0%, 20%, 25%, and 35% by weight of tire shreds). Pullout tests were performed under three normal stresses – 40 kPa, 65 kPa, and 90 kPa. The test results show that the ladder-type metal reinforcement provides higher pullout resistance in tire shred-sand mixtures than in sand alone. Compared to metal-strip reinforcement, ladder-type metal reinforcement provides higher pullout capacity due to the passive resistance that results from the interlocking of tire shreds within the grids of the ladder-type reinforcement. The pullout resistance increased with increasing tire shred content up to 35% (by weight of tire shreds), beyond which segregation of the mixtures was observed.

A key contributor to excessive energy usage in UK domestic dwellings is the poor temperature regulation of fluid filled heat emitters that form the most common constituent of central heating systems. This is in-part due to oversizing of the heat emitters, and deficiencies in localised closed-loop temperature control. In an attempt to address this, Controllable Radiator Valves (CRVs) are becoming an increasingly popular domestic technology with the ability to allow previously unrealisable control schemes to operate the traditional central heating system with minimal mechanical modification. Following previous reported work, therefore, this paper presents a new family of Recursive Modelling Model Predictive Controllers (RM-MPCs) for use with low cost thermic CRVs. The ability of the presented control methodologies to maintain superior temperature regulation despite the use of oversized heat emitters, is a key contribution of the paper. Furthermore, unlike previously reported techniques, the underlying recursive modelling method has been reformulated so that traditional parameter matching calculations do not now require a computationally intensive curve fitting stage. A comparison of techniques is included using experimental measurements from both an oversized oil filled heat emitter within a test chamber, and also from BS EN 442 water-filled heat emitters within an occupied dwelling. Results show the proposed methodologies can be realised using more cost-effective thermoelectric valves, whilst providing superior set point tracking.

The paper proposes a multidisciplinary design optimization (MDO) of permanent magnet synchronous generators (PMSG) for wind energy conversion systems (WECS). Such a MDO seeks the best compromise between the PMSG cost and the lifetime energy production of the WECS. So far, most of the papers in this field presented design methods using quite a few optimization variables and requiring a lot of assumptions. In the proposed MDO the specifications consist of geometrical, economical, magnetic, electrical and thermal constraints. Several analytic and semi-analytic sub-models where used to deal with these constraints, resulting in a large non-linear optimization problem that uses a sequential quadratic programming optimization algorithm. The paper considers the annual wind profile to estimate the lifetime wind turbine energy production. Moreover, the best possible solutions are presented in a Pareto front showing the trade-off between the generator cost and the wind turbine energy production. Among them, one optimal solution machine was chosen to be further investigated and its results were verified by finite element analysis.

This paper describes the development of a new type of tactile sensor which is designed to operate with a piezoelectric element employed as the sensor. Conventional tactile sensors, which consist of a strain gauge, conductive elastomer and piezoelectric polymer film, are confined solely to data acquisition relating to pressure or force. However, the new sensor proposed here is able to detect, very much like the human hand, the hardness and/or softness of an object. Several experiments have been carried out to investigate its possible applications in robotics and medicine. It is demonstrated that the visualization of tactile sensory performance using the new sensor is most useful in a robotics application; the sensor is also able to detect the hardness of an extraneous substance and that of skin.

Software support for the automotive electrical design process is vital, as many of the safety analysis tasks needing to be carried out, while complex, are repetitive and time consuming. Such support is required throughout the design process, but the available commercial tools are only appropriate at specific points in the design process-providing either an early rough analysis or a late but detailed analysis. This paper describes how the capability and utility of safety analysis software can be improved through separating the types of knowledge used into layers. This allows the maximum amount of information to be reused as the design evolves, and enables software tools to track the consequences of changes to the design so that the repercussions of any design change can be understood. The software capability described has profound implications for the design process. Previously, engineers performed a snapshot design safety analysis at some point in the design process, even if they had an automated design safety analysis tool to assist them. The process and tool arrangement described in this paper enables engineers to continually monitor the status of a design, noting the implications of any changes or refinements to the design.

Since emerging more than a century ago, petroleum engineering (PE) education has increasingly kept its popularity despite significant downturns in the industry. During these downturn periods, observed at least four times since the 1973 oil crisis, structural changes in university programs have been considered. On the other hand, during the "heyday" periods, institutions have had to tackle enormous demand from industry, severely increased enrollments, and reestablish resources to provide a proper service. In light of these observations and while experiencing the fifth downturn period over the last five decades, it is time again to ask the same question: "Shall we continue with the same PE education model or radically shift to a new model?" In this paper, after reviewing more than fifty articles published over the last 85 years reporting the attempts made towards reshaping PE education, an option of restructuring PE programs is discussed. This option is less oil industry (and oil prices) dependent and more of a "general" engineering education program with an emphasis on the "geoscience" or "subsurface" engineering aspects of the PE discipline. Detailed discussions focus on curriculum updates to address the industry practice of "subsurface" related engineering applications. Viability of this option was discussed from industry, academia, and students’ perspective. This restructuring option requires substantial changes to curricula, skill development, and teaching and learning styles. Fundamentals are essential to include in PE education similar to other general (or major) engineering disciplines such as mechanical, civil, chemical, and electrical engineering. The essential elements of engineering skills such as creative design, decision making, problem description and solving, management under high degree of uncertainty, and data collection and processing for optimization are to be included in the new model. Finally, the model proposed is critically discussed and analyzed from different perspectives (industry, academia, and students) considering current and prospected subsurface engineering applications.

Grading of potatoes is mostly done by mechanical grading systems. The basis for classification is the square mesh size. In this paper, research on specific dimensions of potatoes is described. It appears that by using a specially developed V-shaped channel the square mesh size of potato tubers of ellipsoidal cross-section can be determined by only one characteristic parameter, the so-called channel height. This new parameter, which is the subject of a patent application, can be used for the development of grading machines based on mechatronic principles.

This paper describes an economic dispatch formulation for a power system control area with high penetration of renewable generation and energy storage. We develop a comprehensive objective function that is unbiased to both the conventional and renewable generation sources. Operating constraints of conventional sources are considered, wind turbine generation is treated as a dispatchable source, and solar photovoltaic generation as negative load. A simulated annealing and particle swarm optimization algorithm are separately applied to minimize the objective function. The results obtained by the proposed economic dispatch formulation show that even a variable energy resource like wind can be dispatched in a manner that benefits the control area as a whole.

In order to improve seismic design technology of bridges, it is necessary to evaluate the vibration characteristics of a bridge–soil system that consists of soil, foundation structure, pier and superstructure. However, there have been few experimental studies on seismic behavior of bridge–soil system. In this paper, we conducted the hybrid vibration experiment on seismic behavior of bridge–soil system, and examined the applicability of hybrid vibration experiment to study seismic response of bridge–soil system. Based on the experiment results, seismic response of bridge was quantitatively studied.

Energy consumption in China is currently dominated by coal, a major source of air pollution and carbon emissions. The utilization of clean coal technologies is a likely strategic choice for China at present, however, although there have been many successes in clean coal technologies worldwide, they are not widely used in China. This paper examines the challenges that China faces in the implementation of such clean coal technologies, where the analysis shows that those drivers that have a negative bearing on the utilization of clean coal in China are mainly non-technical factors such as the low legal liability of atmospheric pollution related to coal use, and the lack of laws and mandatory regulations for clean coal use in China. Policies for the development of clean coal technologies are in their early stages in China, and the lack of laws and detailed implementation requirements for clean coal require resolution in order to accelerate China's clean coal developments. Currently, environmental pollution has gained widespread attention from the wider Chinese populace and taking advantage of this opportunity provides a space in which to regain the initiative to raise people's awareness of clean coal products, and improve enterprises' enthusiasm for clean coal.

Pollutant gases emitted from the civil jet are doing more and more harm to the environment with the rapid development of the global commercial aviation transport. Low environmental impact has become a new requirement for aircraft design. In this paper, estimation method for emission in aircraft conceptual design stage is improved based on the International Civil Aviation Organization (ICAO) aircraft engine emissions databank and the polynomial curve fitting methods. The greenhouse gas emission (CO2 equivalent) per seat per kilometer is proposed to measure the emissions. An approximate sensitive analysis and a multi-objective optimization of aircraft design for tradeoff between greenhouse effect and direct operating cost (DOC) are performed with five geometry variables of wing configuration and two flight operational parameters. The results indicate that reducing the cruise altitude and Mach number may result in a decrease of the greenhouse effect but an increase of DOC. And the two flight operational parameters have more effects on the emissions than the wing configuration. The Pareto-optimal front shows that a decrease of 29.8% in DOC is attained at the expense of an increase of 10.8% in greenhouse gases.

This paper focuses on the integrated berth allocation and quay crane assignment problem in container terminals. We consider the decrease in the marginal productivity of quay cranes and the increase in handling time due to deviation from the desired position. We consider a continuous berth, discretized in small equal-sized sections. A number of enhancements over the state-of-the-art formulation and an Adaptive Large Neighborhood Search (ALNS) heuristic are presented. Computational results reveal that the enhancements improve many of the best-known bounds, and the ALNS outperforms the state-of-the-art heuristics for many instances. We also conduct further analysis on a new larger benchmark.

In this paper, a simplified, yet accurate hybrid model to predict the heat and mass transfer processes in a packed column liquid desiccant dehumidifier is developed. Starting from energy and mass balance principles, and by lumping the geometric parameters and fluids’ thermodynamic coefficients as constants, the derived model only requires two equations together with total seven parameters for predicting the heat and mass transfer status in the dehumidifier. Commissioning information together with Levenberg–Marquardt method can be used to identify these parameters. Compared with the existing liquid desiccant dehumidification system dehumidifier models, the proposed model is very simple, accurate and does not require iterative computations. Experimental results demonstrate their effectiveness in predicting heat and transfer performances over a wide operating range. The model is expected to be applied in operational optimization, performance assessment, fault detection and diagnosis in liquid desiccant dehumidification system.

Fragments and blast waves generated by explosions pose a serious threat to protective structures. Experiments have shown that the single ballistic resistance or blast resistance of the steel plate improves significantly after coating polyurea. However, the dynamic response and structural design for the polyurea-coated structure under the combined fragments and blast loading are still lacking. In this paper, the impact resistance of polyurea-coated steel plate under complex dynamic loading is analyzed and designed for improving comprehensive ballistic and blast resistance using the newly established computational evaluating model. Firstly, according to the thickness and placement effects of the coating on the ballistic and blast resistance, the steel-core sandwich plates are designed, which are proved to own outstanding comprehensive ballistic and blast resistance. Besides, the distribution diagram of ballistic and blast resistance for different polyurea-coated steel plates is given to guide the design of protective structures applying in different explosion scenarios. Furthermore, the dynamic response of designed plates under two scenarios with combined fragments and blast loading is studied. The results show that the synergistic effect of the combined loading is significant. It reduces both the ballistic and blast resistance of the polyurea-coated steel plate and causes a more severe failure than the sum of the failures induced by the individual fragments and blast impact. Besides, the acting sequence of the fragments and blast affects the structural protective performance heavily. It is found that the first loading inducing structural large deformation or damage generally is dominant. In the scenario of fragments penetrating firstly, the excellent unit-thickness ballistic performance of the structural front part is strongly needed for improving the comprehensive ballistic and blast resistance. The analysis of dynamic response and structural design for the polyurea-coated steel plate in this paper will be helpful for designing lightweight protection structures with excellent comprehensive ballistic and blast resistance.

In this paper, the dynamic characteristics of the KALIMER (Korea Advanced LIquid MEtal Reactor) IHTS hot leg piping system conveying hot liquid sodium are investigated to eliminate the pipe supports for economic reasons. To do this, a 3-dimensional straight pipe element and a curved pipe element conveying fluid are formulated using the dynamic stiffness method of the wave approach and coded to be applied to any complex piping system. Using this method, the dynamic characteristics including the natural frequency, the frequency response functions, and the dynamic instability due to the pipe internal flow velocity are analyzed. As one of the design parameters, the vibration energy flow is also analyzed to investigate the disturbance transmission paths for the resonant excitation and the non-resonant excitations.

This paper discusses the use of EN ISO and EN ISO/IEC standards within the monitoring and reporting regulation and verification regulation. These regulations determine, as their titles might suggest, how (operators of) installations and aircraft operators must determine their emissions, how a verifier must verify emissions, and how verifiers must be accredited. These regulations make extensive use of reference to EN ISO and EN ISO/IEC standards, notably EN ISO/IEC 17011:2004, EN ISO 14065:2013, EN ISO/IEC 17025 and EN ISO 9001. The question arises if these references are in conformity with Article 297 TFEU. A comparative analysis is made with a recent discussion in Dutch jurisprudence and literature about the reference to private standards in Dutch national legislation.

Performance based evaluations are commonly completed as part of the human factors verification and validation of control rooms of new builds or substantial modernizations in Nuclear Power Plants. The validation of the Main Control Room system in the nuclear industry entails the assessment of specific performance components such as plant performance, situation awareness, workload, task performance, and anthropometric and physiological factors. This evaluation is expected to take place in realistic contexts, simulating the plant's operation and covering also abnormal and emergency operation situations. There is a vast set of measures to address these human performance components, and the relations among the different concepts and different measures are not clearly defined. The measures used to assess human performance can also vary significantly regarding the type of rater (self-rated, observer-rated, objective ratings), the type of scale (rating scales, correct/incorrect decisions, open answer, acceptability judgments), the moment of rating (online rating, end of scenario, scenario freezes), among others. In this paper we try to analyze these relationships between task performance, workload, and situation awareness. We explored the results of both self-rated, observer-rated, and objective measures. We explored the relations between and within measures, as well as the trends across the different assessments, affected by control room modifications. The results indicate a similar pattern in workload and situation awareness measures through evaluations; that the relations within self-rated measures appear to be clearer than between self-rated and observer-rated measures; and that there seems to be a trend for improved task performance results in the control room throughout the years.

Accumulation of unmanaged industrial or agricultural solid waste especially in developing countries has resulted in an increased environmental concern. Recycling of such wastes as a sustainable construction material appears to be viable solution not only to pollution problem but also an economical option to design of green buildings. In view of utilization of industrial and agricultural waste material for developing sustainable construction material, the present paper reviews various waste materials in different compositions that were added to the raw material at different levels to develop waste-create bricks (WCB). Various physico-mechanical and thermal properties of the bricks incorporating different waste materials are reviewed and recommendations are suggested as the outcome of the study. The reviewed approach for the design and development of WCB using industrial solid waste is useful to provide a potential sustainable solution.

Smart materials have played significant contribution towards the development of buildings. There are various smart materials which can change their properties and behavior under the influence of external catalyst or stimulus. Such materials are changing the face of traditional engineering materials. Smart materials can be utilized individually as well as it can be incorporated with existing materials to enhance their desirable properties. Smart materials are widespread across all the domains of human inventions due to its multidisciplinary applications. Some of these materials are relatively new while some are being used from a very long time. Hence it suffices to say that the recently developed smart materials still require research. The general classification of smart material is illustrated in this review paper. The paper intends to identify the various types of available smart materials and also illustrated the application of such materials in the various fields of civil engineering. Further, the potential benefits and downsides are also discussed along with their applicability under different conditions. Some innovative materials are also discussed which can bring potential revolution in the construction industry. The impact or the benefits related to sustainability also discussed in this review paper.

In the growing technology automobile industries plays an importance role. The tire industry is a part of automobile industry. The growing practice in the tire industry is to replace Initial wheel size machinery of a car of a greater wheel dia. and a smaller aspect tyre with the similar diameter is replaced by the pneumatics. This activity is usually synonymous with retailing, and automotive manufactures are facing an increasing inclination for new vehicles to suit the bigger tyres. This paper explores general practise and its influence on the performance characteristics of the automobile. This research is aimed at demonstrating how the plus-size pneumatic affects all vehicle performance as well as stability. Any complex tyre influence that could impact the performance of the system will be addressed and preliminary performance data will be provided on the dynamic influence of plus sizing.

Air suspension system is been used by vehicle manufacturers since decades. Earlier it was only used by the commercial vehicle but soon the manufacturers and the users found the need of air suspension in commercial vehicles as well. Nowadays this system can mostly be seen in luxury vehicles, the application of air suspension has come a long way, earlier when it was installed in commercial vehicles, it was generally used for raising and lowering ride height to accommodate different sizes of trails, but later air suspension system majorly started to be used as a luxury feature because manufacturers invented that it was providing supreme ride and comfort especially when comparing with traditional spring mechanism used in suspension. Therefore all the luxury cars are using air suspension to provide supreme comfort during riding even through rough terrains. This paper discusses about the different applications of air suspension discussing about the working and its advantages and disadvantages.

This study is aimed to judiciously generate the desired alternative configurations of a given single-contaminant water-using system under the constraints of minimum freshwater usage, minimum match number and minimum total throughput. A generalized source-shift procedure is proposed for this purpose, which can be applied manually by evolution from a preliminary network which requires minimum freshwater usage. Systematic implementation guidelines are also provided to perform the evolution steps. In addition, the minimum interconnection number can be estimated in advance and the total number of promising alternative solutions can also be determined a priori . Six examples are presented in this paper to demonstrate the effectiveness and benefits of applying our method.

Active structural methods constitute a promising way to mitigate chatter vibrations in milling. This paper presents an active system integrated into a spindle unit. Two different optimal control strategies are investigated. The first one only considers the dynamics of the machine structure in the controller design and minimizes the influence of cutting forces on tool tip deviations. The second one takes explicitly the process interaction into account and attempts to guarantee the stability of the overall closed-loop system for specific machining conditions. The modeling and formulation used for both strategies are presented in this first part. A simulation allows the comparison of their respective working principle. The validation of the proposed concept in experimental conditions is described in the second part.

The paper deals with an application of neural networks for detection of natural periods of vibrations of prefabricated, medium height buildings. The neural network technique is also used to simulate the dynamic response at selected floor of one of the analysed buildings subject to seismic loading induced by explosives in a nearby quarry. Both the training and testing patterns were formulated on the basis of measurements performed on actual structures. The results of neural network identification of natural periods of the considered buildings obtained with different soil, geometrical and stiffness parameters are compared with the results of experiments. The application of back-propagation neural networks enables us to identify the natural periods of the buildings with accuracy quite satisfactory for engineering practice. The experimental and generated data of vibration displacements are compared and much clearer comparison is given on the phase plane: displacements versus velocities. It was stated that a good generalization takes place both with respect to displacements and velocities.

The subseabed is currently being considered as a disposal site for nuclear waste, and if it does become an option, monitoring to detect escape of the disposed material will be essential. In this paper, we define types of nuclear waste and present the dimensions of the monitoring problems that would be encountered in ocean disposal. We then summarize the characteristics of a number of physical, chemical, biological, and ecological monitoring methods. We also describe the advances and developments that will be necessary before the monitoring functions and support systems can be employed.

This paper describes the electroacoustic behaviour of a new piezoelectric Active Noise Reduction (ANR) earplug device. The sensor is a microphone having suitable characteristics chosen from among commercially available electret microphones. The actuator is a cylindrical piezoelectric ceramic loaded with a thin fluid film. An analytic model of laterally radiating loudspeaker, based on fundamental equations of acoustics, which takes into account the effect of viscosity and heat conduction is adapted to describe the acoustic radiation of the actuator. Theoretical and experimental frequency responses in a small cavity and an example of the ANR that can be obtained with the earplug are presented.

This work is a continuation and verification of the original literature by means of experiment. According to the previously published paper, the criteria of synchronization and stability for three co-rotating three exciters in an analytical form, as well as their numerical results, are directly provided. A synchronization experiment with three exciters is carried out. The experimental data on phase differences, rotational velocities, system responses, coupling torques, and so on, are quantitatively discussed by dividing the operational processes of the system into four stages. The coupling torques, which are the key determining factors for implementing synchronization, are particularly examined to explain the synchronization regime, based on the average energy method. The quality of synchronization is provided, and the noise and uncertainties in the experimental data are analyzed. It is shown that the experimental results obtained concur with the theoretical results.

The limited natural water resources in the world pressures the scientist and engineers to develop alternative sources which are brackish/seawater desalination. Seawater desalination process selection is a critical decision based on geographical location, energy costs and availability as well as operator skills. A decision maker requires much updated information related to desalination technologies to put huge investment in the right place. The present paper will describe the popular desalination processes being used nowadays in the world and their latest developments, advantages and challenges to compete each other to produce reliable and cheapest potable water. This paper will indicate ideas to improve a technology. MARAFIQ with its existing facilities and future projects will significantly contribute in this field. The paper also will explore the desalination processes in MARAFIQ and 800,000 m3/d future promising IWPP.

In tilis paper, a new methodology for active noise control is proposed and experimentally demonstrated. The method is based on Adaptive Neuro Fuzzy Inferen e Systems (ANFIS), which is introduced to overcome nonJinearity inherent in active noise control. Filtered-X ANFIS algoritlun for leaning is derived. Experiment is performed using Texas Instruments C6701 DSP Board. In contrast to previous work on ANC using computational intelligence approaches which concentrate on single channel and off-line adaptation. this research addresses multichannel and employs onHne adaptation. which are possible because of the computing power of the DSP.

Despite various safety inspections carried out over the years to ensure compliance with regulations and maintain acceptable and safe working conditions, construction is still among the most dangerous industries responsible for a large portion of the total worker fatalities. A construction worker has a chance of 1-in-200 of dying on the job during a 45-year career, mainly due to fires, falls, and being struck or caught-in/between objects. This in part can be attributed to how monitoring the presence and proper use of personal protective equipment (PPE) by safety officers becomes inefficient when surveying large areas and a considerable number of workers. Therefore, this paper takes the initial steps and aims at evaluating existing computer vision techniques, namely object detection methods, in rapidly detecting whether workers are wearing hardhats from images captured on many indoor jobsites. Experiments have been conducted and results highlighted the potential of cascade classifiers, in particular, in accurately and precisely detecting hardhats under various scenarios and for repetitive runs.

This paper presents two expert systems designed to serve as a control center operator's assistant. The first is designed to assist operators in solving overload problems and the second is to assist in solving voltage problems. Both systems use the distribution factor concept to create indices for the decision-making process. A new improved technique to obtain the distribution factors is presented. That technique circumvents part of the problems introduced by the linearization implicit in the use of distribution factors and makes them suitable to be used to solve voltage problems. A 634-bus model of an actual electrical system and its interconnections is used so that the results can be realistically compared with the action that would be taken in the control center. Results are reached in a manner consistent with the operation of the control center and in a time frame that makes these expert systems feasible for real-time applications.

The paper describes a high precision gas meter suitable for low rates of flow (< 5 cm3 min−1) which can be interfaced with data acquisition software for continuous on-line measurement. The meter used the highly sensitive pressure transducers currently available, operated with a very small back pressure, and had an accuracy around 0.5%. A frequency to voltage converter was developed and built into the gas meter. This allowed direct connection to a data logger/computer without prior computation.

The paper deals with some special questions of experimental research being important when frames are tested and the load carrying capacity of the structure is lost because of any instability phenomena. Computer simulation results are presented: • -to illustrat the difference between the real and ‘virtual’ structural behaviour, which is dependent on the character of loading, and • -to show that in certain conditions a structure, which became unstable because of the instability of one of its elements, is able to turn to a stable state and to carry increasing loads before complete loss of its load carrying capacity. This paper is a modified (slightly extended) version of that which was presented during the ‘First International Conference on Coupled Instabilities in Metal Structures’. Reflections of participants initiated some modification.

Government support, in the form of publicly-funded R&D and block purchases of satellites or launch vehicles by space agencies, plays a critical role in structuring commercial markets for space applications such as telecommunications and Earth observation. This paper provides a comparative analysis of the different support mechanisms which benefit the space industries of the United States, Western Europe, Japan and other countries, discusses their effects on commercial competition, and quantifies the levels of support and their economic effects.

This paper presents the results of a design study of a large scale dual purpose power/water plant for the production of 200 MWe of power for sale and 83 imgpd of fresh water. The plant comprises a steam generating heavy water reactor (S.G.H.W.R.) with associated power plant and eight multi-stage flash distillation units each with a capacity of 10.4 imgpd. An estimate of the overall capital cost of the facilities is given and the cost of fresh water is estimated at a stated power price.

A new approach of gear fault diagnosis based on continuous wavelet transform is presented. Continuous wavelet transform can provide a finer scale resolution than orthogonal wavelet transform. It is more suitable for extracting mechanical fault information. In this paper, the concept of time-averaged wavelet spectrum (TAWS) based on Morlet continuous wavelet transform is proposed. Two fault diagnosis methods named spectrum comparison method (SCM) and feature energy method (FEM) based on TAWS are established. The results of the application to gearbox gear fault diagnosis show that TAWS can effectively extract gear fault information. The feature energy of the TAWS features the gear fault advancement very well and is conically proportional to the gear fault advancement.

The active wave control of the linear, axially moving string with general boundary conditions is presented in this paper. Considerations of general boundary conditions are important from both practical and experimental viewpoints. The active control law is established by employing the idea of wave cancellation. An exact, closed-form expression for the transverse response of the controlled system, consisting of the flexible structure, the wave controller, and the sensing and actuating devices, is derived in the frequency domain. Two actuation forces, one upstream and one downstream of an excitation force, are applied. The proposed control law shows that all modes of the string are controlled and the vibration in the regions upstream and downstream of the control forces can be cancelled. However, these results are based on ideal conditions and the assumption of zero initial conditions at the non-fixed boundaries. Effects of non-zero boundary motions at the instant of application of the control forces are examined and the control is shown to be effective under these conditions. The stability and robustness of the control forces are improved by the introduction of a stabilization coefficient in the control law. The effectiveness, robustness and stability of the control forces are demonstrated by simulations and verified by experiments on axially moving belt drive and chain drive systems.

Smart grid engineering is the key for a beneficial use of widespread energy resources, it is a modernized electrical grid that uses analog or digital information and communications technology. Renewable energy itself a thrust area of research due to its availability, applicability and environmental friendly nature and the application of smart grid in renewable energy makes it vast and more promising. This fusion enables the efficient use of renewable energies which is a key challenge for now. The present review paper attempts to investigate the role of smart grid in the renewable energy. The introductory section sets the role of renewable energy and distributed power in a smart grid system. Subsections cover the concept and availability of renewable energies, renewable energy power calculation formulae, smart grid concepts and its feasibility, case studied as performed by different researchers around the World, discussion and future recommendations and finally the conclusions from the study. To achieve this, articles from different sources such as internet, reports, conferences and journals of Elsevier, Springer, Tailor and Franacis, Wiley and many more have been collected and reviewed. This paper concludes that renewable energies can be used efficiently and in a smart way by using the smart grids. However, the smart grid technology is not mature enough and needs more research on the same.

The dynamics of large span flexible roof systems are significantly influenced by the internal pressure which acts both to stiffen and to damp roof motions. The present paper is concerned primarily with roof systems covering vented spaces, i.e. a structure with wall openings. It is demonstrated that the added mass associated with flow through wall openings plays only a minor role for distributed openings and that even for large distributed openings it can be ignored with little loss of accuracy. Sample calculations show that the dynamic motions in the volume-changing modes of the roof are strongly dependent on the size of the wall openings, with increases by a factor of about 5 as the total wall opening is changed from 1/10% of the effective roof area to 10% of the effective roof area.

The economic evaluation of concentrated solar-steam gasification of empty cotton boll biomass along with co-production of potassic fertilizer from residual ash was carried out. The study considered four different plant capacities: 5 MWSyn, 10 MWSyn, 15 MWSyn and 20 MWSyn in terms of syngas power and two different methods for synthesis of potassic fertilizer: (1) fractional crystallization, and (2) selective precipitation. The key process parameters like energy efficiencies and mass flow rates, based on experimental results were studied in-depth with a sensitivity analysis. It was found that the heliostat field was the most expensive component of the plant, while the synthesis of potassic fertilizer was economically feasible for all the tested plant capacities. The selective precipitation was found to be gainful than the fractional crystallization. The levelized cost for the liquid fuel via Fischer Tropsch synthesis was estimated at 0.90 USD L−1 for the 20 MWSyn plant. The trends indicate that levelized cost for liquid fuel could further be reduced by increasing the plant capacity. The solar steam-gasification of empty cotton boll biomass has the potential to mitigate the CO2 emissions by 86% compared to conventional fossil fuel. The potassic fertilizer recovered from the residual ash can cover 31% of the annual potassic fertilizer requirement of the cotton fields that originally supplied the feedstock.

Biodiesel is an alternative fuel mainly produced from vegetable oil or animal fats. It is a renewable substitute of regular fuel. As a replacement of petroleum fuel it is much cleaner alternative. Its physical components are much similar to diesel fuel. Renewable sources are used to create biodiesel. Sources like new or used vegetable oil and animal fats are not toxic and can be broken down by living organisms using a special process. To complete the process an alcohol, mostly methanol is used to create a chemical reaction with these oils and fats. After the reaction, we get a new liquid substance called fatty acid methyl esters. We call it biodiesel when we use it as fuel. Coconut oil is used as biofuel in the present paper. It is used directly or can be mixed with diesel as a blend and is used to find the performance of four-stroke diesel engine.

The AIT (Advanced Information Technology for the European Manufacturing Industry) initiative is focusing on IT innovations and their integration in the users enterprise. This is achieved through the deployment of the AIT Innovation Cycle starting with the AIT strategic planning (development of a common master plan) and finishing with the business integration of complete IT innovative solutions. The IT integration includes two major action streams supported by various R&D projects belonging to the ESPRIT and Brite Euram research programmes, which are: ⋅ The technological integration which is achieved in strong cooperation with IT vendors through the development of integration platforms based on emerging standards such as STEP, CORBA, JAVA, etc. In this integration context, the CIMOSA framework has been used to build the AIT IT Reference Model (ITRM). ⋅ The IT innovations integration into the users' enterprise which consider the usage of all the CIMOSA views (function view, information view, organisation view, resources view including Human, Financial and IT resources) as well as their aggregation in order to support the development of generic networked enterprise (re)engineering methodologies, processes and associated IT supporting tools. This paper is focusing on the second integration stream by describing the progress achieved to date in the AIT-IMPLANT project. The aim of this ESPRIT project is to develop a generic enterprise change management methodology and associated IT tools to support the integration of IT Innovations into the networked manufacturing enterprises.

The longitudinal stability characteristics of a Wing-In-Ground (WIG) effect craft are quite different from those of the conventional airplane due to the existence of force and moment derivatives with regard to height. These stability characteristics play an important role in designing a safe and efficient WIG due to its potential danger in sea surface proximity. The static and dynamic stability criteria are derived from the motion equations of WIG in the framework of small disturbance theory and discussed in this paper. The static and dynamic stability analyses of a 20-passenger WIG are conducted based on wind tunnel test data, and dynamic motion behaviors are investigated for changes in design parameters. Finally, the flying quality of the 20-passenger WIG is analyzed at cruising conditions according to the military regulations.