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The current synchronized motion control methods used in paper machine drives are not designed to possess the inter-shaft stiffness properties which were responsible for the coordinating force inherent in classical, mechanically coupled paper machines. Consequently, these controllers cannot easily maintain coordination for all operating conditions. This paper presents the application of an "electronic line-shafting" control technique which serves to replicate and even improve on the historical, mechanical line-shafted properties. This technique was tested on a four-shaft experimental set up to evaluate such control during periods of drive-limited torque as well as sectional drive load disturbances. The experimental results demonstrate that the "electronic line-shafting" technique significantly improves the coordination, robustness and overall stability of paper machine drives subjected to realistic physical limitations.

Computer-aided design and manufacture (CAD/CAM) have enabled advances in the design and manufacture of many accelerator components, though government procurement rules tend to inhibit its use. We developed and executed a method that provides adequate documentation for the procurement process, industrial vendor manufacturing processes, and laboratory installation activities. We detail our experiences in the design and manufacture of 60 separate and unique PEP-II Low Energy Ring Interaction Region vacuum chambers totalling /spl sim/140 m in length as an example of how we used this technique, reducing design effort and manufacturing risk while streamlining the production process. We provide "lessons learned" to better implement and execute the process in subsequent iterations. We present our study to determine the estimated savings in the design and production of the Spallation Neutron Source room temperature linac if this process were utilized.

The concept of Life Extending Control is defined. Life is defined In terms of mechanical fatigue life. A brief description is given of the current approach to life prediction using a local, cyclic, stress-strain approach for a critical system component. An alternative approach to life prediction based on a continuous functional relationship to component performance is proposed. Based on cyclic life prediction an approach to Life Extending Control, called the Life Management Approach is proposed. A second approach, also based on cyclic life prediction, called the Implicit Approach, is presented. Assuming the existence of the alternative functional life prediction approach, two additional concepts for Life Extending Control are presented. These are called the Measured Damage Approach, and the Estimated Damage Approach. A simple, hydraulic actuator driven, position control system example is used to illustrate the main ideas behind the Life Extending Control concept and is based on a cyclic fatigue damage model. Some results are given which demonstrate that system durability can be maximized by more effectively managing the resource of critical component life. Some additional research is proposed to develop a functional life prediction method and to demonstrate the concept of Life Extending Control.

This paper investigated the influence of paper-wrapped on the deposition of sulfur corrosion on the insulation winding (paper-wrapped copper conductor) in oil-immersed insulation containing dibenzyl disulfide (DBDS). The distribution of sulfur corrosion deposit on a 500-kV electric reactor was investigated and analyzed, and the properties of oil were analyzed. Aging experiments were also conducted for oil-paper insulation with 500-mg/kg DBDS under IEC 62535 corrosion test condition. The corrosion degree of insulation winding was evaluated, and the properties of oil were also discussed. Results showed that the enwinding pattern of the insulating paper on the copper conductor affected the deposition distribution of copper sulfide to be an alternate appearance of a non-corroded crevice and a strip-shaped corrosion deposit on the copper conductor according to the results of field and laboratory. Furthermore, for the insulation winding, the increased number of paper layers on the copper conductor led to the aggravation of sulfur corrosion, prevented the diffusion of copper ions in the oil, and accelerated the formation of acids, which co-affected the properties of the oil. The enwinding of insulating paper on the copper conductor led to the appearance of a tiny crevice on the insulation winding, which is an important occurrence precondition of crevice corrosion. Finally, the mechanism underlying crevice corrosion for insulation winding was theorized as electrochemical corrosion leading to copper sulfide formation.

This Research-to-Practice Full Paper presents the redesign of a course project to promote student professional formation in engineering in the Electrical and Computer Engineering Department at Iowa State University. This is part of a larger effort to redesign core courses in the sophomore and junior years through a collaborative instructional model and pedagogical approaches that promote professional formation. A required sophomore course on embedded computer systems has been assessed and revised over multiple semesters. The redesign of the project was initiated with the purpose of promoting student professional formation, interest, autonomy and innovation, and it was undertaken using a collaborative process. This paper describes the course, final project, redesign process, assessment, results and future work. Several conclusions from the research may be useful to other educators. A small change to the course project yielded positive effects in interest and autonomy and may influence longer term effects of the project. There was evidence of difference in engagement with the project. The difference observed was not only due to option selected by students but why students selected the option.

The European Union (EU) regulations require the pilots of Unmanned Aircraft System (UAS) to register and pass a basic theory exam from 2021. Therefore, it is essential to systematically gather information for pilots for utilizing UAS in a safe and meaningful manner especially in Nordic weather conditions. This book chapter describes the Nordic challenges for UAS operations. These can be categorized into two main categories: technological and operational. Based on the extensive literature review and practical experience of the authors, both categories of challenges especially with relevance to the severe Arctic weather conditions are presented. The relevant weather conditions include changing the density of the air, dust and solid particles clouds, extreme light conditions, freezing rain, heavy and gusty wind, heavy clouds, ice fog, rain, mist and fog combinations, rapid temperature changes, snow, storm and hailstorm, temperature crossing 0 C several times within 24 hours, wind shear and whirlwind. Many technical and operational challenges (e.g., weather-related phenomena) are overlapping on both categories and can be mitigated partly by technological advances and partly by operational preparedness. Finally, the future challenges and needs in UAS research are also discussed.

Power transformers are crucial elements in electrical systems, and the end of their useful life is commonly conditioned by the degradation of the cellulosic insulation materials inside them. These materials are subjected to elevated temperatures and mechanical stresses, generated by electrical solicitations which deform the copper conductors and subsequently the paper, and also to the chemical reactions which take place in the dielectric oil in which the paper is impregnated. In order to better understand the behaviour of cellulosic insulation, we have studied the previous bibliography analysing the mechanical behaviour of cellulosic materials. At present, there are no experimental results analysing how the paper responds to the deformation suffered by the copper conductor in a realistic situation. We have developed a simulation model describing the mechanical behaviour of a standardised copper conductor wrapped with four layers of dielectric paper, using ANSYS Workbench Static Structural, which will be compared with experimental results afterwards.

The world is becoming an immense critical information infrastructure, with the fast and increasing entanglement of utilities, telecommunications, Internet, cloud, and the emerging IoT tissue. This may create enormous opportunities, but also brings about similarly extreme security and dependability risks. We predict an increase in very sophisticated targeted attacks, or advanced persistent threats (APT), and claim that this calls for expanding the frontier of security and dependability methods and techniques used in our current CII. Extreme threats require extreme defenses: we propose resilience as a unifying paradigm to endow systems with the capability of dynamically and automatically handling extreme adversary power, and sustaining perpetual and unattended operation. In this position paper, we present this vision and describe our methodology, as well as the assurance arguments we make for the ultra-resilient components and protocols they enable, illustrated with case studies in progress.

Power transformers are one of the most critical components of power systems, and failures often result in significant economic loss from the interruption of power and damage of assets. The establishment of maintenance programs that signal abnormal conditions in transformers is essential for the reliable operation of these equipments. However, in a competitive market, it is important to maximize investments by depleting the remaining life of the equipments before replacing them. The end of life of a transformer comes about by aging of its solid insulation, which is mainly Kraft paper, pressboard, and wood, and these materials age mainly by hydrolysis reactions. Although transformer lifetimes are considered to be about 30 years, experience shows that some transformers remain in service for more than 50 years [1]. Aging of cellulosic insulation depends mainly on operating temperature, moisture, oxygen, and acids. The value of these factors depends on the operating conditions and maintenance practices, which are not always accurately quantified. Having a method to estimate the remaining life of a transformer is essential for owners to assess the risk of keeping a transformer in service or the necessity of replacing it. Unfortunately, estimating the remaining life of transformer insulation is not an easy task because it is not possible to extract paper samples from the active part of the transformer to make direct determinations, and estimations are always based on indirect estimations. On the other hand, the transformer temperature is not homogeneous, so the condition of the paper varies within the transformer, which makes the analysis even more complex. The determination of the furanic compounds content in the transformer oil is one of the more valuable methods to diagnose the aging condition of transformer solid insulation [2]. Unlike other markers, for example CO or CO2, which are produced during the degradation of cellulosic insulation but also mineral oil, furanic compounds are exclusively generated as a by-product of the aging reactions of only cellulose insulation, and that makes the diagnosis more reliable.

Designing complex adaptive systems for real world applications is a delicate challenge, especially when support for humans in crucial situations should be achieved. In this position paper, we propose a multi-agent based approach for physically reconfigurable, heterogeneous robot swarms. These can be deployed when there is a need to search, continuously observe and react, e.g. in disaster scenarios. We show first results that validate the feasibility of our approach.

We study a cooperation model where the positions of base stations follow a Poisson point process distribution and where Voronoi cells define the planar areas associated with them. For the service of each user, either one or two base stations are involved. If two, these cooperate by exchange of user data and reduced channel information (channel phase, second neighbour interference) with conferencing over some backhaul link. The total user transmission power is split between them and a common message is encoded, which is coherently transmitted by the stations. The decision for a user to choose service with or without cooperation is directed by a family of geometric policies. The suggested policies further control the shape of coverage contours in favor of cell-edge areas. Analytic expressions based on stochastic geometry are derived for the coverage probability in the network. Their numerical evaluation shows benefits from cooperation, which are enhanced when Dirty Paper Coding is applied to eliminate the second neighbour interference., 6 pages, 4 figures, conference. In proceedings of 47th Asilomar Conference on Signals, Systems and Computers 2013 (invited paper)

Introduction of renewable energy resources especially Solar Photovoltaic (PV) supports the green economy requirements. Solar PV technologies have become the most prominent green energy resources towards Malaysia energy mix by the year 2020. Despite the significant reduction of carbon emission, Solar PV farm requires a huge open area for electricity generation and furthermore, the space under each of the PV arrays are not utilised for any economical activities. This study extents the potentials PV arrays as herbal plots with Orthosiphon Stamineus deposited directly under the array structures without any disturbances to the PV operation. The aims of this work are to conduct sampling tests to determine the yield of crude extraction from the herbs by using the soxhlet extraction method, characterizing the phenolic compound and identifying the potential of bioactive compound from the extracts. Laboratory result shows that the highest crude extraction was 16.992% which is at par with samples from naturally grown locations. The highest Total Phenolic Content (TPC) of extract are recorded at 844.83 GAE/100g by using 70:30 ratio of methanol to water concentration ratio and 720 minutes of extraction time.

This paper proposes a new disposable soft 3D force sensor that can be used to calculate either force or displacement and vibrations. It uses three Hall Effect sensors orthogonally placed around a cylindrical beam made of silicon rubber. A niobium permanent magnet is inside the silicon. When a force is applied to the end of the cylinder, it is compressed and bent to the opposite side of the force displacing the magnet. This displacement causes change in the magnetic flux around the ratiomatric linear sensors (Hall Effect sensors). By analysing these changes, we calculate the force or displacement in three directions using a lookup table. This sensor can be used in minimal invasive surgery and haptic feedback applications. The cheap construction, bio-compatibility and ease of miniaturization are few advantages of this sensor. The sensor design, and its characterization are presented in this work.

This position paper argues that industry tracks have no place in any research conference. Instead, a research conference should always have room for industrial case studies, evaluated according to criteria for empirical research. Such case studies would not be acceptable at a practitioners’ industrial conference, just as papers presented at such conferences would not be acceptable at research conferences. It follows as corollary that if researchers want to become familiar with problems and solutions of RE practice, they should visit industrial conferences.

This article is a position paper whose purpose is to give the context for presentations in a special session at PowerTech 2013. The special session is being proposed by the EU FP7 Real-Smart Consortium, a Marie Curie Industry-Academic Pathways and Partnerships project. The paper gives an overview of topics on modeling, monitoring and management of power transmission dynamics with participation from large industrial loads. © 2013 IEEE.

We consider a multiuser multiple-input multiple output (MIMO) Gaussian broadcast channel (BC). Assuming a sum-power constraint over all transmit antennas, the sum capacity of such a system can be achieved with dirty paper coding (DPC) which has been found as a very promising strategy. Rather than the usual sum-power constraint, in this paper we focus on the downlink of a cooperative multicellular network where each transmit antenna has an individual power constraint. This scenario is much more realistic than the case where a sum power constraint is considered, since in practical systems transmit antennas have their own power amplifiers. We extend this approach to the scenario where each base station (BS) is assumed to have an individual power constraint. We propose a capacity calculation algorithm which is able to take both per-BS and per-antenna power constraints into account.

Laboratory experiences should be available for a great number of students in engineering education, especially at times when the number of students is even more increasing. Virtual Labs and Remote Labs are innovative tools used for improvement. They are either simulating experiments (Virtual Labs) or remotely operated plants (Remote Labs). At Ruhr-University Bochum, the implementation of eight new labs was supported by the project ELLI (excellent teaching and learning in engineering sciences). Didactical concepts as well as sustainable implementations were among the criteria of the independent jury's decision. After their setup, the management of the variety of labs is the next step. This short paper reports the work in progress in the year 2013, the whole process is to be continued and improved.

This paper describes the application of statistical analysis to the on-site diagnostic data of HV power cables to set-up knowledge rules and measuring criteria for particular cable insulations and accessory (joints, terminations). Such approaches can successfully be employed later in Asset Management decision processes. In this paper based on different cable data populations of two diagnostic parameters like: partial discharges and tan delta, statistical analysis has been applied. Besides this, several practical examples also have been presented.

This paper explores the use of a multivariate statistics approach to monitor and diagnose the performance of a steam heated drying process. The results presented in this paper are a first stage investigation into the capabilities and limitations of these methods when applied to this particular process. The results show that, despite the non-linear behaviour of the drier process, the model predictions correspond well with the process measurements. The results also indicate ability to detect process failures, however, accurate diagnosis of the failures remains a subject for future studies

Recent information-theoretic results show the optimality of dirty-paper coding (DPC) in achieving the full capacity region of the Gaussian multiple-input multiple-output (MIMO) broadcast channel (BC). This paper presents a DPC based code design for BCs. We consider the case in which there is an individual rate/signal-to-interference-plus-noise ratio (SINR) constraint for each user. For a fixed transmitter power, we choose the linear transmit precoding matrix such that the SINRs at users are uniformly maximized, thus ensuring the best bit-error rate performance. We start with Cover's simplest two-user Gaussian BC and present a coding scheme that operates 1.44 dB from the boundary of the capacity region at the rate of one bit per real sample (b/s) for each user. We then extend the coding strategy to a two-user MIMO Gaussian BC with two transmit antennas at the base-station and develop the first limit-approaching code design using nested turbo codes for DPC. At the rate of 1 b/s for each user, our design operates 1.48 dB from the capacity region boundary. We also consider the performance of our scheme over a slow fading BC. For two transmit antennas, simulation results indicate a performance loss of only 1.4 dB, 1.64 dB and 1.99 dB from the theoretical limit in terms of the total transmission power for the two, three and four user case, respectively.

The pinus is a type of wood that is widely used as feedstock for the production of softwood pulp and higher quality paper, boards, MDF (Medium Density Fiberboard), OSB (Oriented Standard Board), plywood, furniture and others. The main problem for the pinus is the attack by the wood wasps (Sirex noctilio F., 1793) (Hymenoptera; Siricidae) that damages the wood due to galleries built by the wasps larvae. The use of nondestructive techniques to assess the quality and to evaluate mechanically the wood has been the focus of many studies and is certainly an essential tool to decrease the production costs. This work aimed to evaluate the damage due to the infestation of S. noctilio in Pinus taeda L. using ultrasound. The tests have been carried out in the through transmission mode, using a pulser-receiver, two pairs of ultrasound transducers (50 kHz and 100 kHz of central frequencies for each), a digital oscilloscope and a portable microcomputer for data storage. The initial tests have been done using seven logs of pinus samples (lengths in the range 0.70 - 0.94 m and diameters 0.09 - 0.18 m). The transducers were positioned in the samples to measure the ultrasound propagation velocity and the attenuation in the axial, radial (lower, middle and upper parts of the logs), longitudinal (middle and upper parts), inclined at approximately 45 degrees (middle and upper parts), longitudinal/transversal (middle and upper parts) and inclined/transversal (middle and upper parts) modes. The initial results of the 960 tests (430 with each pair of transducers) that have been done with the pinus samples have shown that the infested samples presented a decrease in the propagation velocity and an increase in the attenuation when compared to the control sample results. The initial results showed that the ultrasound technique can help the quality evaluation of P. taeda and to detect the infestation of wood wasps. Further tests should be made with a larger number of samples to evaluate the elastic modulus and other ultrasound parameters. The results will be used to define a novel test protocol to be used for material characterization in the agronomical area.

This review paper summarizes state-of-the-art energy management methods applied to electrical systems of large aircraft. An electrical load management based on fixed priorities of the loads is considered a conventional implementation as applied in today’s aircraft systems. It can cut and reconnect loads depending on their importance. The advantages and disadvantages of such a system are presented. Further implementations are depicted that are able to eliminate certain drawbacks of such a typical load management. Most promising is the exploitation of so-called slow responding loads which can be handled like an electrical storage. The optimization potential on future energy management functions is finally discussed and conclusions are drawn.

Opportunistic interference management (OIM) is an approach that can asymptotically achieve dirty paper coding (DPC) capacity in the downlink of wireless cellular networks with minimum feedback requirement. With K antennas at the base station and M mobile users in the cell, the proposed technique requires only K integer numbers related to channel state information (CSI). This multiplexing gain of K is achieved at the expense of M mobile users such that K = Θ(logM). We introduce an antenna selection scheme at the base station to reduce the minimum number of required mobile users significantly at the expense of reasonable increase in feedback.

We introduce a new interference management technique for wireless cellular networks when the base station (BS) has K antennas and there are M mobile stations (MS), each with a single antenna. Our interference management scheme takes advantage of multiuser diversity to transmit K independent data streams to K out of M mobile stations. The new approach achieves the dirty paper coding (DPC) capacity of K log log(M) as M tends to infinity. Surprisingly, the new scheme does not require full channel state information (CSI) and needs only close to K integers related to CSI are fed back to the transmitter. Moreover, the encoding and decoding of the new scheme is significantly simpler than existing MIMO schemes and is similar to point-to-point communications.

IT companies are confronted with a huge, growing Off-the-Shelf (OTS) marketplace containing incredibly large amount of diverse, partial, ephemeral, sometimes tacit and not always trustable information about OTS components. Our empirical studies illustrate that different users, such as OTS evaluator, OTS integrator, system tester, and system maintainer, need different information and knowledge about OTS components when facing different scenarios. Although a few companies are using mini-wikis internally to manage and share OTS related knowledge, knowledge sharing across companies is rare. Searching existing web portals or sites of OTS components is time consuming and often does not bring systematic knowledge. This position paper proposes role-based wikis to organize OTS components related knowledge in a systematic way. One motivation of constructing such a wiki is to provide necessary knowledge for different users to help them reduce risks. Another motivation is to provide a global centralized platform, so that OTS users can systematically share their knowledge across organizations.

We consider the downlink of a cellular multiple input single output (MISO) system with multiple users per cell. Fast scheduling and spatial signal processing at the base stations result in unpredictable non-stationary intercell interference when the base stations do not cooperate. We show how the per cell sum-rate can be increased when Kalman filters are employed to forecast the interference power for the next transmission. We compare these results for dirty-paper coding and beamforming to systems where the intercell interference powers are perfectly known through feedback channels or cooperating base stations and to systems where outdated information is used.

An effective and economic process for removing arsenic in waste water which is acuminating in the process of etching, cutting and washing in semiconductor industry has been developed in this paper. The proposed technique of arsenic removal is in three steps: first pretreatment step is to oxidize arsenite to arsenate by potassium permanganate, second key step is precipitation based on arsenic compound solubility with ferric sulfate and slaked lime under pH adjustment, and the last complementary step is followed by the adsorption of the bentonite with enhanced by activated carbon and organic adsorbent. Experimental results show that under the best condition the removal efficiency of arsenic in the waste water is better than 99.99%, or the concentration of arsenic is from its original 100 mg/l reduced to less than 10 mug/l accordingly.

SOA is now in widespread use by the industry and is a current area of interest for research. However a currently open area of investigation is how to properly introduce SOA in an IT/CS/SwE type of curriculum. Software engineering students must develop a series of abilities and skills related to SOA for effective professional practice. Providing environments where students go beyond learning some concepts and specific technologies to truly apprehend the complexity involved in SOA is a major challenge. This environment must be articulated in the context of business needs and other software architecture methodologies. Instructors need a new set of skills and abilities to tackle this challenge. This position paper discusses what such an environment should provide for students and instructors to effectively develop skills that will enable SOA practice in the business world.