Integrated Fibre Optic Subsea System

Consistent definition, categorization and operationalization of product service systems delivered to the markets and customized for different segments is one of the major challenges for the Product Lifecycle Management (PLM) in the telecommunications industry. Each lifecycle encompasses the processes, information, support systems, culture and people involved in delivering the related business functions. It can be argued that process supporting solutions like WFMS, PDM etc. exist today for the creation of a seamless environment for accessing, manipulating and reasoning about product information that is being produced in fragmented and distributed environment. A holistic approach that is suitable for aligning the Product Lifecycle Management (PLM) business requirements to the potentials of new technology driven concepts in the information management like SOA as well as to the environmental and economic aspects over the complete product lifecycle is nevertheless still missing. The authors give reasons why the holistic view on the product lifecycle management is critical for an efficient PLM and present an integrated approach for developing of product service systems compatible with the requirements of sustainability and profitability for the business. In this paper four building blocks of Next Generation PLM are introduced: 1) Product Meta Model; 2) PLM-Process; 3) PLM IT-Architecture; 4) Lifecycle Value Management concept for steering the PLM process on a strategic level like, among other things, by considering portfolio effects. The paper closes with the presentation of a short case study validating the proposed concept for a company in the telecommunication industry.

In this paper, a control system for two wheeled inverted pendulum robot is implemented to have more stable balancing capability than the conventional control system. Fuzzy control structure is chosen for the two wheeled inverted pendulum robot, and fuzzy membership function factors for the control system are obtained for 3 specified weights using a trial-and-error method. Next a neural network is employed to generate fuzzy membership function factors for more stable control performance when the weight is arbitrarily selected. Through some experiments, we find that the proposed fuzzy control system using the neural network is superior to the conventional fuzzy control system.

To operate two-inertia systems with high speed and precision, a control method to suppress mechanical resonance is required. A conventional current control system consists of a proportional integral controller and decoupling controller, and the conventional current control system has high motor torque control performance. However, the conventional current control system tends to excite mechanical resonance. This paper proposes a new current control system to suppress the resonance of a two-inertia system by using the cross-coupling term of a surface permanent magnet synchronous motor. The proposed control system consists of a proportional controller and voltage disturbance observer to estimate the voltage disturbance without including the cross-coupling term that is used as a damping control. The effectiveness of the proposed control system is validated by numerical simulations and experiments.

The purpose of the study was to investigate project management best practices in Nigeria’s telecommunication industry. Data was collected across 379 telecommunication firms and analyzed using the descriptive method. The study found that telecommunication firms in Nigeria adopt the best project management practices. Best project management practices are widespread in the telecommunication industry in Nigeria. The project management practices adopted by telecommunication firms include holding initial meetings of all the project stakeholders, the development of project scope management, keeping all related parties updated throughout the project’s lifecycle, the creating of resource plan, the creation of a response risk team, transparency in the implementation of projects, setting realistic project milestone and review of project performance.

A primary requirement for a communication headet is to maintain speech intelligibility under all conditions of use. For headsets equipped with active noise reduction (ANR), the performance of the control system may influence the communication signal reaching the ear. Conversely, the communication signal may perturb the operation of the ANR system. The interaction between the communication and control signals will depend primarily on the control structure, and the electro-acoustic transfer function of the earphone and drive electronics of the communication channel. The effect on speech intelligibility will be described using the speech transmission index, for circumaural headsets employing feedback control with a fixed filter and analog signal processing, an approach commonly used in commercial devices, and one employing adaptive, digital feed-forward control. In each case, the active control systems attempt to control low-frequency noise, as the passive attenuation of the earmuff enclosing the ear substantially reduces noise at frequencies above 500 Hz. Results will be discussed for different environmental noise spectra, and speech-to-noise ratios.

People can instantaneously create novel conventions that link individual communicative signals to meanings, both in experiments and everyday communication. Yet a basic principle of natural communication is that the meaning of a signal typically contrasts with the meanings of alternative signals that were available but not chosen. That is, communicative conventions typically form a system, rather than consisting of isolated signal-meaning pairs. Accordingly, creating a novel convention linking a specific signal and meaning seems to require creating a system of conventions linking possible signals to possible meanings, of which the signal-meaning pair to be communicated is merely a sub-case. If so, people will not link signals and meanings in isolation; signal-meaning pairings will depend on alternative signals and meanings. We outline and address theoretical challenges concerning how instantaneous conventions can be formed, building on prior work on “virtual bargaining,” in which people simulate the results of a process of negotiation concerning which convention, or system of conventions, to choose. Moreover, we demonstrate empirically that instantaneous systems of conventions can flexibly be created in a ‘minimal’ experimental paradigm. Experimental evidence from 158 people playing a novel signaling game shows that modifying both the set of signals, and the set of meanings, can indeed systematically modify the signal-meaning mappings that people may instantaneously construct. While consistent with the virtual bargaining account, accounting for these results may be challenging for some accounts of pragmatic inference.

This paper presents a technique to cope with undesirable frictional effects in positioning control of a pneumatic actuator. This technique is based on an observer for estimating the dynamically varying friction force on-line. The observer is derived from an available nonlinear observer for Coulomb friction by modifying it to fit the pneumatic actuator and to enhance its estimation ability. Our pneumatic servo system for positioning consists of an inner pressure control loop, an outer position control loop, the friction observer, and a velocity observer. In this system, the friction force is compensated by adjusting a desired pressure value sent from the outer loop to the inner loop according to the friction observer output. Experimental comparisons with a conventional control system using friction compensation by means of accelerometer information feedback were carried out and show that our system works with almost the same high positioning accuracy as the conventional system, despite having neither an accelerometer nor a velocity sensor, and is more advantageous from the perspective of cost performance.

O objetivo deste trabalho foi avaliar a influência da transpiração do tomateiro na fração lixiviada e na condutividade elétrica (CE) da solução nutritiva percolada no substrato de areia, em cultivo realizado sob condições de casa-de-vegetação. Foram utilizadas duas técnicas de fertirrigação, sendo uma denominada de sistema de controle convencional e outra, de sistema de controle computadorizado. No sistema de controle convencional, a solução nutritiva foi aplicada em intervalos de tempo fixos entre eventos de fertirrigação. No outro sistema, a aplicação ocorreu de acordo com estimativas de transpiração que foram realizadas pelo algoritmo de controle do sistema computadorizado. Em dias nublados, a CE da solução nutritiva drenada diminuiu em ambos os sistemas, em decorrência da baixa transpiração e da alta fração lixiviada, o que amenizou a salinização do substrato. Entretanto, em altos valores de radiação solar, a CE aumentou devido à baixa lixiviação. Os resultados demonstraram que, em condições de nebulosidade, o sistema de controle computadorizado reduziu o volume de efluentes em 54% em relação ao sistema de controle convencional e, simultaneamente, impediu a salinização do substrato por meio da manutenção da CE média diária da solução drenada entre 2,9 e 3,5 dS m-1.

For the huge energy losses of the conventional hydraulic valve-controlled servo control system, a new Multi-level Pressure Switching Control System (MPSCS) was coined and proposed in this study to address this issue. First, the discrete force distribution and switching rules of MPSCS was designed for conducting the four-quadrant working principle. Second, the hybrid control strategy was designed and applied for a displacement control system with three-level pressure rails. Finally, an experiment rig was established to validate proposals above in this study. The experimental results approved the pump input power and throttling losses of MPSCS was decreased dramatically compared with the conventional displacement control system, but the response time, position jitter etc. were still challenges to MPSCS.

The paper discusses the features of the Biomass Boiler drum water level. Conventional PID Control System can not reach a satisfaction result in nonlinearity and time different from Biomass Boiler Drum Water Control System. In this study, a kind of fuzzy self-adaptive PID controller is described and this controller is used in biomass boiler’s drum water level control system. Using the simulink tool of MATLAB simulation software to simulate the fuzzy adaptive PID and conventional PID control system, the result of the comparison shows that the fuzzy self-adaptive PID has the strong anti-jamming, flexibility and adaptability as well as the higher control precision in Biomass Boiler Drum Water.

Direct digital frequency synthesis (DDS) as an indispensable key technology for modern communication systems, is widely used in digital communications, satellite communications, aerospace and high-speed instrumentation. In practical applications, DDS technology is usually required to generate different kinds of communication signals. In view of the fact that there is no related research on spurious signals when DDS technology generates communication signals, this paper based on a DDS model that can generate arbitrary symbol rate communication signals, analyzes spurious signals of the structure in detail. The conclusions of this paper can be used for the spur evaluation and parameter selection in DDS engineering applications. At the same time, this paper provides a theoretical basis for the low spurious design of DDS, and has certain reference value for DDS to generate communication signals.

The article examines the factors that affect efficiency of enterprises in telecommunication industry in Russian Federation over the past decade on the example of three major telecommunication companies, MTS, MegaFon, and VimpelCom that control more than 80% of the market.The paper describes main characteristics of the companies and builds multiple regression models.The study is based on data from the State Statistics Committee of Russia, annual reports and websites of telecommunication companies, market surveys, for the period 2005-2013.Our results suggest that the success of the Russian telecommunications companies is primarily associated with the size of investment in fixed assets, the expenditures on advertising, the dynamics of the average cost of cellular communication services, as well as the growth of the national telecommunications market and the level of inflation in the country.Our results are in accord with the idea that success of the operators in the current conditions is largely dependent on investment and technology opportunities for early coverage area (population) new networks 3G/3.5G/4G, and successful marketing strategies to promote mobile services data (mobile internet) on the basis of these networks in the context of growing competition in this segment of the market.

Inerter-based structural vibration control: A state-of-the-art review

Conventional electro-hydraulic servo control system is widely used for mold oscillation, but it is difficult for this system to construct a stable, low cost and high performance control system. This paper proposes an oscillation method driven by an electro-hydraulic-controlled stepping cylinder, and the stepping cylinder has the performances of less control links, easy maintenance, relatively low cost and high precision. The mathematic model of electro-hydraulic-controlled stepping cylinder is established, and through PWM control the sine curve and non-sinusoidal curve are simulated. The result of simulation demonstrates that the model is effective, and the proposed electro-hydraulic-controlled stepping cylinder system instead of conventional electro-hydraulic servo control system is feasible.

Combustion engineering: Kazutomo Ohtake and Toshitaka Fujiwara, (in Japanese), Corona Publishing Co., Ltd., Tokyo, 1985, v + 215 pp., 2300 yen.