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The purpose of this paper is to reveal the effect of starting time on hydro-viscous drive speed regulating start.

The modified transient Reynolds equation, thermal energy equation and temperature–viscosity equation were solved simultaneously by using finite element method. And then variations of the oil film load capacity, variations of temperature and variations of the torque generated by the oil film during the starting process were obtained.

The results show that during the starting process, both the oil film load capacity and the temperature show an upward trend, the torque increases during the beginning period and then decreases during the latter part of the starting process. When the starting time is less than 60 s, variations of the oil film load capacity and temperature show fluctuations, which decrease with the starting time. For any output speed, the corresponding oil film load capacity, temperature and torque decrease with the starting time, and the decreasing amplitude also decreases with the starting time.

This paper indicates that the starting time can be set to 60-90 s to obtain a perfect starting process. The simulation results are verified by the speed regulating start experiments. Research findings of this work provide theoretical basis for the design and practical application of the hydro-viscous drive equipments.

The form and content of relationship value dominates the literature. This paper contributes by studying companies’ actions based on their value perceptions, a field which has attracted less attention. Scholars advocate more studies on how companies’ value perceptions shape actions in relationships and how this leads to outcomes.

A longitudinal critical case study of a customer/supplier relationship constitutes the empirical basis of the paper. Interviews and observation studies were conducted over a period of three years, giving access to special insight into the actors’ value perceptions and related actions.

Value perceptions shape actions performed individually, jointly or in the wider network. Moreover, misperceptions of the counterparty’s value perceptions may result in a maelstrom of interactions with no specific value outcome. Acting based on value perceptions is a complex matter due to its evolving nature, which leads to development becoming a value driver.

The interdependencies between different value perceptions and their relational value drivers have special effects on actions and outcomes, also, value in actions needs to be studied.

Management needs to explore value from different perspectives to understand the counterparty’s value perceptions and communicate own perceptions. It is not sufficient to create value based on one value driver. Instead, it is vital to be able to connect value drivers to balance and prioritise relevant actions.

This paper stands out as one of the first contributions to relationship value literature that addresses and analyses value from both a customer perspective and a supplier perspective in a dyadic business relationship.

The purpose of this paper is to reveal the effect of working oil temperature, load and starting time on hydro‐viscous drive speed‐regulating start.

The authors developed an experimental equipment and carried out a number of experiments under different temperatures, load and starting time.

The results show that both the temperature rise of working oil and the increase of load can induce fluctuations in output speed, but the effect of the working oil temperature rise is more serious; also the longer the starting time is, the more perfectly the output speed can trace the given speed.

It indicates that the working oil temperature should be kept in a certain range by using a cooling device in practical application; and that under this experimental condition, kinematics viscosity of the working oil should be greater than 45 mm²/s under rated working temperature, and the relatively suitable starting time should range from 90 to 120 s.

The paper explains the effect of various factors on speed‐regulating start, and provides the basis for the design and the application of hydro‐viscous drives.

In this work, generation control of an isolated small hydro plant (SHP) is demonstrated by applying optimal controllers in speed governor and hydraulic turbine system. A comparative analysis of application of fuzzy PI (FPI) and PID controller is conferred for generation control (both power and terminal voltage) of an SHP. The controllers are designed optimally by using crow search algorithm (CSA) and novel hybrid differential evolution crow search algorithm (DECSA). The purpose of this paper is to settle the voltage and real power to improve the quality of the power.

In this work, the controllers (PID and FPI) are implemented in speed governor and excitation system of SHP to regulate power and terminal voltage. Differential evolution and CSA are hybridized to enhance the performance of controller to refurbish the power and terminal voltage of SHP.

The proposed DECSA algorithm is applied to solve ten benchmark functions, and the effectiveness of DECSA algorithm over CSA and DE is demonstrated in terms of best value, mean and standard deviation. CSA and DECSA algorithms optimized controllers (PID and FPI) are used to design SHP with the capability to contribute power and voltage of better quality. The comparative analysis to substantiate the competence of DECSA algorithm and FPI controller is demonstrated in terms of statistical measures of power and voltage of SHP. Robustness analysis is performed by varying all system parameters to prove the effectiveness of the proposed controller.

The proposed algorithm and FPI controller are applied individually to improve the quality of the power of SHP. DE, CSA and DECSA algorithms are implemented to solve benchmark equations. The solutions of all benchmark equations contributed by DECSA algorithm is converged rapidly and having minimum statistical measures as compared to DE and CSA algorithms. The DECSA algorithm and FPI controller are proposed with superior competence to enhance the generator performances by conceding undershoot, overshoot and settling time of power and terminal voltage. DECSA-based FPI controller contributes a noticeable improvement of the performances over other approaches.

Presents a guide for development of certifiable quality management systems for the library and information sector. The project was supported by NORDINFO and was carried out in 1993‐94. Begins with an introduction to fundamental ISO 9000 philosophy, definitions and concepts. All 20 main points of ISO 9001 receive a thorough treatment with respect to the library and information sector. The staff members concerned describe experiences from two test sites (Norsk Hydro and Telecom Denmark‐Jutland Telephone Co.) and analyse the two reports. Describes the implementation of ISO 9000 in the library and information sector in practice in general terms. Describes four examples of typical library and information routines in detail, together with relevant quality requirements. Analyses the process of certification and reports the findings of an empirical survey in the Nordic countries. Aims at a general quality improvement of information services and products, and at developing new tools for quality improvement.

The purpose of this paper is to present the results of acoustic emission (AE) and ultrasonic inspection of two H₂S storage tanks carried out in a heavy water plant, in order to characterize point type defects observed during earlier ultrasonic inspection and to ensure that these defects are not growing during hydrotesting of the tanks.

Using multiple AE sensors and AE source location methodology, the entire tank could be covered to detect and locate any dynamic sources of AE associated with local plastic deformation and/or growing discontinuities from any part of the tank during the hydrotest. For confirmation of the results obtained by AE, ultrasonic inspection on the tanks and on virgin plates from which the tanks were manufactured, were carried out.

The AE signals generated during first pressurisation are attributed to the micro yielding of the material of the tanks. A few scattered AE events were observed at a few locations during the hydrotesting of the tanks and these are due to structural and rubbing noise. During hold periods and repressurising cycle of the hydrotesting, no detectable AE events were observed and this confirmed the absence of any growing discontinuity in the tanks during the hydrotesting. Ultrasonic inspection on the tanks and on virgin plates confirmed that the point type defects detected are manufacturing defects and not formed during service life.

The combined results from AE and ultrasonic techniques confirmed the structural integrity of the tanks and ensured their healthiness for continued operation.

The paper brings out the use of AE and ultrasonic techniques for monitoring hydrotesting of storage tanks of a heavy water plant. The storage tanks where point type defect indications were reported during previous ultrasonic inspection and whether these defects are growing during hydrotesting of the tanks or not, were required to be known before the tanks are put in to further service. AE signals collected during pressurising and repressurising cycles of the hydrotest and subsequent inspection by ultrasonic confirmed the vessels to be free from growing defects during the hydrotest and provided baseline data for future inspection.

In this work, the authors show the performance of the proposed diploid scheme (a representation where each individual contains two genotypes) with respect to two dynamic optimization problems, while addressing drawbacks the authors have identified in previous works which compare diploid evolutionary algorithms (EAs) to standard EAs. The paper aims to discuss this issue.

In the proposed diploid representation of EA, each individual possesses two copies of the genotype. In order to convert this pair of genotypes to a single phenotype, each genotype is individually evaluated in relation to the fitness function and the best genotype is presented as the phenotype. In order to provide a fair and objective comparison, the authors make sure to compare populations which contain the same amount of genetic information, where the only difference is the arrangement and interpretation of the information. The two representations are compared using two shifting fitness functions which change at regular intervals to displace the global optimum to a new position.

For small fitness landscapes the haploid (standard) and diploid algorithms perform comparably and are able to find the global optimum very quickly. However, as the search space increases, rediscovering the global optimum becomes more difficult and the diploid algorithm outperforms the haploid algorithm with respect to how fast it relocates the new optimum. Since both algorithms use the same amount of genetic information, it is only fair to conclude it is the unique arrangement of the diploid algorithm that allows it to explore the search space better.

The diploid representation presented here is novel in that instead of adopting a dominance scheme for each allele (value) in the vector of values that is the genotype, dominance is adopted across the entire genotype in relation to its homologue. As a result, this representation can be extended across any alphabet, for any optimization function.

To develop structured guidelines for the synthesis of dynamic force simulators that are required for the testing of high speed aerospace actuators. To provide realistic and proven solutions at both test bench hardware and control design levels.

The state of the art in control design applied to load simulators in mainly based on complex controllers and does not take into account practical considerations. The objective of the present work is to provide generic preliminary design rules to ensure that the test bench architectures (frame, power transmission and control) and the components specifications are consistent with the targeted performance. Once selected the appropriate power transmission architecture, a linear approach is used as a foundation to generate design rules. Then, preliminary design is achieved thanks to the introduction, as early as possible, of the unavoidable technological defects.

A step‐by‐step methodology allows the designer to select the controller architecture and to specify components with special care to their consistency with the required dynamic performance. The linear then practical approach generates key rules that can be used in the very early phase of the test bench design.

Practical considerations on the components static and dynamic limitations are introduced progressively to make the natural test bench performance as consistent as possible with the performance requirements. Consequently, the controller becomes simpler to design and robust.

The purpose of this paper is to develop a procedure for deciding on the limits of initial clearance to which tubesheet holes can be enlarged before replacement in heat exchanger maintenance.

An empirical model that relates the hardness of roller expanded tubes and ligaments to initial clearance is developed from experimental data to predict the extent of tolerable levels of over‐enlargement of tubesheet holes before the joint loses its structural integrity. The developed model serves as an additional criterion to decide whether to keep or discard a tubesheet having over‐enlarged holes during heat exchanger maintenance.

The current industrial criterion does not directly include the effect of material degradation for over‐enlarged holes. The empirical models indicate that both tubes and ligaments suffer strain hardenings. A new procedure is proposed to supplement the current industrial criterion.

The procedure will assist maintenance managers/engineers in deciding on the replacement of heat exchanger tubesheets. The combined criteria will have an impact on the cost of heat exchanger maintenance and plant downtime.

The procedure proposed in this paper adds to the industrial criterion another one that caters for the degradation in properties that the tube, tubesheet, and surrounding ligaments will be subjected to during roller expansion. In other words, it considers the strain hardening of the tube and tubesheet materials in setting the initial clearance between the tube and tubesheet that ensures adequate joint integrity.

This characteristic is important enough in aircraft maintenance to be covered separately. Considerably less embrittlement than that in bath plating is realized in selective plating. With one proprietary solution, Cadmium LHE (Code SPS 5070), hydrogen embrittlement is almost negligible. Selectively plated nickel and nickel‐tungsten alloys also can be plated with so little hydrogen content that no baking for embrittle‐content that no baking for embrittlement relief is required.