Front-end Phase Research Articles

Regenerative Cascaded Cell Inverter with Active Filter

In the medium voltage application it is very beneficial to use cascaded inverters. Traditionally, this type of inverter is based on diode front end and bulky phase shifting transformer. Due to the demand of 4 quadrant drives and more severe grid requirement, the cascaded inverters with active front end have been started to emerge in the market. This article introduces regenerative cascade inverter topologies. After a short summary about the topologies, single-phase cell solution with NPC is analyzed in detail. Since one of the most challenging problems is the elimination of low order grid harmonic at low motor speed, the article demonstrates the origin of this harmonics. After the clarification of the harmonic generation phenomenon, a novel harmonic elimination method is introduced. Apart from the description of the new elimination concept, the proper controller structure is described as well. Finally, the performance of the novel method is verified by Matlab simulation.

Front end Governance of Major Public Projects - Lessons with a Norwegian Quality Assurance Scheme

Governance regimes for major investment projects comprise the processes and systems that need to be in place on behalf of the financing party to ensure successful investments. This would typically include a regulatory framework to ensure adequate quality at entry, compliance with agreed objectives, management and resolution of issues that may arise during the project, etc., and standards for quality review of key governance documents. The challenges are abundant: How to ensure projects' viability and relevance up-front; how to avoid hidden agendas during planning, underestimation of costs and overestimation of utility, unrealistic and inconsistent assumptions; how to secure essential planning data, adequate contract regimes, etc. This paper discusses measures in terms of governance regimes that might improve success in public investment projects. Success is defined at two levels; 1) operational (eciency and cost control), and 2) strategic (eectiveness and viability) . As a special case, we present the Norwegian project governance regime applicable to major public projects, which has existed since year 2000. It comprises two quality assurance exercises in the front-end phase, aimed to ensure an adequate basis for the political go/no go decisions, but with no involvement during project implementation. The experience we have so far is positive and shows that the regime most likely leads to more successful projects at both levels.

A descriptive framework of the design process from a dual cognitive-engineering perspective

This article proposes a new descriptive framework, which we label as the “ideation framework” (IF), of the design process from a dual cognitive-engineering perspective, partly based on existing frameworks from both fields and previous work by the author. The framework is for the ideation or front-end phase of the product development process, representing the interface between cognitive psychology and engineering design. Three domains – inspiration, decomposition, and integration – and three spaces – problem-space, idea-space, and concept-space – are the elements of the framework. The iterative flow of the engineering design process passes through the three domains in a semi-controlled way, through a sequence of specialization and generalization process loops in and between the spaces. An empirical descriptive examination of the ideation process is performed using designers with limited design experience. The designers were faced with a design problem that they had to solve in a limited period of time. Their designs were analyzed, and a post-exercise interview was done to uncover each of the participants' design process. The empirical work indicates these designers worked in a manner largely consistent with the IF.

A Calibrated Digital Sideband Separating Spectrometer for Radio Astronomy Applications

ABSTRACTDual sideband (2SB) receivers are well suited for the spectral observation of complex astronomical signals over a wide frequency range. They are extensively used in radio astronomy, their main advantages being to avoid spectral confusion and to diminish effective system temperature by a factor 2 with respect to double sideband (DSB) receivers. Using available millimeter-wave analog technology, wideband 2SB receivers generally obtain sideband rejection ratios (SRR) of 10–15 dB, insufficient for a number of astronomical applications. We report here the design and implementation of an FPGA-based sideband separating FFT spectrometer. A 4 GHz analog front end was built to test the design and measure sideband rejection. The setup uses a 2SB front end architecture, except that the mixer outputs are directly digitized before the IF hybrid, using two 8 bit ADCs sampling at 1 GSPS. The IF hybrid is implemented on the FPGA together with a set of calibration vectors that, properly chosen, compensate for the analog front end amplitude and phase imbalances. The calibrated receiver exhibits a sideband rejection ratio in excess of 40 dB for the entire 2 GHz RF bandwidth.

Dynamic Partial Least Square Path Modeling for the Front-end Product Design and Development

The dynamic nature of today’s technology market requires new value-characteristic modeling methods; mainstream methods have limitations due to unrealistic assumptions, such as static customer preferences and no multicollinearity among product attributes. In particular, products with longer cycle times can suffer because the static model ignores changes in the market during the concept-to-customer lead time. This study proposes a dynamic, partial least squares path model for customer driven product design and development in order to reduce model uncertainty by formulating preference models to reflect market dynamics. The proposed dynamic model adopted partial least squares regression to handle the limited observations plagued by multicollinearity among product attributes. The main advantage of the proposed model is its ability to evaluate design alternatives during the front-end concept screening phase, using the overall product-value metric, customer-revealed value. A case study analyzing the US car market data for sedans from 1990 to 2010 showed the potential for the proposed method to be effective, with a 3.40 mean absolute percentage error.

New Product Development Processes and New Product Profitability: Exploring the Mediating Role of Speed to Market and Product Quality

In new product development, faster is not always better. Conceptually, being faster to market should improve financial performance by improving product quality and reducing development expenses. Empirical support is mixed, however, demonstrating that higher speed to market exhibits an inverted U-shaped relationship with product profitability. Conventional wisdom and empirical research suggest managers make speed to market‐product quality‐development expense trade-offs. A particular concern regarding speed to market is that extreme speed may jeopardize product quality. Some researchers suggest that speed to market improves product quality while others suggest firms must balance both speed to market and product quality. Also, shorter lead times may be associated with reduced development expenses, but empirical evidence is conflicting. This research attempts to reconcile conflicting results regarding the speed to market‐product quality relationship, their joint impact on product profitability, and their mediation role in the effects of development expenses and cross-functional integration on product profitability. Partial least squares (PLS) is used to analyze multiplexed archival and survey data collected from NPD managers for 1115 different NPD projects in several firms. The results support the hypothesized equations, explaining 27% of speed to market variance, 35% of product quality variance, and 45% of product profitability variance. This study makes two contributions. First, because speed to market and product quality are related, simultaneous consideration of both factors enhances insight into their joint effect. Second, it provides evidence that speed to market and product quality jointly mediate development expense by NPD phase and cross-functional integration effects on product profitability. Key results from the large sample data analysis include the following. Speed to market and product quality both enhance product profitability, but the impact of speed to market is larger than that of product quality. Speed to market and product quality partially mediate the impact of fuzzy front end phase expenses on product profitability, while expenses in the latter phases exhibit no impact on the mediators or profitability. Thus, the results suggest that trade-offs are made not only between time, quality, and expense (i.e., if additional expenses are incurred at all), but also that trade-offs relate to when (i.e., in which NPD phase) additional development expenses are incurred. Finally, crossfunctional integration (both internal and external) substantially impacts product profitability through a mix of direct and mediated effects.

Where process development begins: A multiple case study of front end activities in process firms

The front end phase of the new product development has been examined extensively, yet few if any studies have examined the front end phase of new process development. By means of a multiple case study of process firms, this article aims to bridge this knowledge gap. Our results show that substantial differences in front end activities exist between the product development and process development domains. We conceptualize the front end in process development to be an iterative trial-and-error process, dominated by activities such as idea generation and refinement, literature reviews, anticipation of end-product changes, and various forms of experiments in bench scale, lab scale, and full-scale production. In addition, we highlight key problems in the front end and managerial remedies for how to mitigate them. While these findings provide theoretical implications for research into product development, process development and production management, the findings are particularly relevant to process development managers, plant managers, and development engineers interested in increasing the efficiency of production processes.

A living laboratory for managing the front-end phase of innovation adoption: the case of RFID implementation

The recent interest in radio frequency identification (RFID) technologies offers an interesting opportunity for researchers to examine the different phases of the innovation process. Although this technology has improved substantially over the last few years, its adoption by the business community still raises some challenges and unanswered questions for both developers and potential users. This paper provides a detailed description of an actual innovative project to implement RFID. It also provides a strong argument for dedicated organisational settings in which open innovation project management can develop through a living lab. The advent of the living laboratory approach as an innovation platform characterised by 'users as innovators' cooperating in an open and neutral research environment has generated many theoretical and practical findings that have greatly enriched the literature on project fuzzy front-end (FFE). We propose a conceptual framework with four main dimensions that encompasses the complexity of this type of undertaking, in which project success is considered from the standpoint of both the developer and the adopter. This approach proved to be an efficient way to reduce fuzziness at the early project implementation stages.

IMPROVING INNOVATION CAPABILITIES OF SMALL ENTERPRISES: CLUSTER STRATEGY AS A TOOL

This study focuses on innovation capabilities in small enterprises and how their development can be supported by regional strategies. The study utilizes multiple case studies. The empirical evidence is based on data from four regions in Finland. Each of them has adopted an industrial cluster approach as the basis of regional development. The study draws a common framework for assessing how regional development efforts meet the needs of innovation development in small enterprises. The findings demonstrate that most of the efforts for improving innovation capabilities of small enterprises are appropriate for innovation generation in the front-end phase. Instead, there were no significant efforts to support innovation adoption. Further, the highly conceptualised development services provided by a variety of public organizations meet the needs of large companies. However, these services match poorly with the nature of innovation development in small enterprises.

Il costo dell'Alta Velocitŕ ferroviaria in Italia

- Cost overruns are common in large and complex projects, especially in high speed rail ones. Budgeting for cost escalation is a major issue in the planning phase of these projects. This paper describes lessons learned on high speed rail in Italy and focuses on problems such as initial poor design, tactical budgeting, inadequate cost estimation and risk assessment, etc. The paper discusses possible means to avoid major flaws in the initial conceptual design of mega-projects. There is a growing understanding of the need to focus on the front-end phase in order to achieve more successful and cost-effective projects.

Development Of A Consultation Profile Of Interventions Perceived As Successful By Human Performance Technology Consultants

The purpose of this study was to develop a consultation profile of interventions perceived as successful by internal or external Human Performance Technology consultants. Members of the National Society for Performance and Instruction [The National Society for Performance and Instruction is currently known as the International Society for Performance and Instruction] and the American Society for Training and Development were asked to describe in detail a single intervention which they considered successful in terms of outcomes for both themselves and their clients. The results indicate that the scope of these interventions is not limited to training but includes a broader range of performance improvement interventions. This supports the notion that professionals in the field are undertaking more systemic approaches in their practice. An average of 40% of total project time is allocated to front-end analysis. The projects reported by our respondents also emphasize collaborative decision-making, especially during the front-end analysis phase. Factors most commonly reported as responsible for the success of projects were support from the client, collaboration between team members, and clear definition of expectations.

Antecedence and consequence in design rationale systems

AbstractIdentification of latent or unarticulated customer and other stakeholder needs has been a significant barrier to improving the efficiency and effectiveness of the front-end phase of new product development processes. In-depth determination of stakeholder needs entails analysis of their intentions; the overall aim of the work reported in this article is to establish a framework of intentional analysis, and its associated methods and techniques for improving traceability of design practice during the early phases of the design process. The specific aim of this article is to present a conceptual framework for design rationale systems. The framework built upon the cross-fertilization of approaches and methods drawn from systems engineering and philosophy, focussing on the notions of antecedence and consequence. It was developed in the course of tackling design problems originating in industrial contexts. The methods developed were thus evaluated, updated, and refined in real applications. Two application cases are described that have been drawn from the aerospace and power sectors, respectively. The applications showed that the framework's central antecedent/consequent scheme provides a cell from which to develop either a history of actual successive changes, or a tree of alternative possible projected designs.

The fuzzy front end of Japanese new product development projects: impact on success and differences between incremental and radical projects

This study of Japanese New Product Development (NPD) projects explores the fuzzy front end of innovation. The goal of the paper is twofold: First, we analyse the impact of the fuzzy front end on the success of all the NPD projects. We develop a conceptual model based on the information‐processing approach. A structural equation model was fitted to data from 497 NPD projects in Japanese manufacturing firms to test the proposed model. The empirical analysis suggests that an early reduction of market and technical uncertainty as well as an initial planning before development have a positive impact on NPD project success. The model accounts for 17% of the variance of the efficiency and 24% of the variance of the effectiveness‐dependent variable. Thus, the front end phase is an important driver of NPD project success. Second, we compare the fuzzy front end of incremental to radical NPD projects. Although these projects differ in many aspects of newness, we found only a few differences with regard to the fuzzy front end. For instance, it was more difficult to estimate the market size and price sensitivity of the customers during the fuzzy front end of the radical NPD projects compared with the incremental projects. Implications of the empirical results and limitations of the study are discussed.

STRATEGIC AND OPERATIVE LEVEL FRONT-END INNOVATION ACTIVITIES — INTEGRATION PERSPECTIVE

The front-end phase is in the literature generally regarded as the most critical phase of the innovation process. Front-end management has a strategic nature since important decisions related e.g. to target markets and the main functionalities of products are done in the front-end phase. This article examines how the integration of strategic and operative level front-end activities is perceived by top managers in the product innovation context. The findings indicate that companies exploit different strategy-making processes, and that each strategy-making mode is prone to particular integration challenges. The results show that the effectiveness of integration of strategic and operative level front-end activities is dependent on the level of concreteness of the defined business strategies, the amount of business-minded decision making, and the balance between control and creativity.

Enhancing the front-end phase of design methodology

Design methodology (DM) is defined by the procedural path, expressed in design models, and techniques or methods used to untangle the various activities within a design model. Design education in universities is mainly based on descriptive design models. Much knowledge and organization have been built into DM to facilitate design teaching. However, the present paper points out that the current practice of handling the front-end phase of design by starting with an assigned problem is a weakness in design teaching. It is proposed to enhance this phase by considering problem conception as an activity. Students should be trained how to generate or create product opportunities in addition to developing them into products. Several techniques of teaching this ‘new’ activity are outlined in the paper. It is concluded that this approach will create designers who are total innovators rather than just product developers, which is in line with today’s business competitive world.

Extreme customer innovation in the front-end: learning from a new software paradigm

The front-end phase of the innovation process constitutes up to two-thirds of the total cost of new product development (NPD). In response to the new open innovation paradigm, new ways to integrate customers' knowledge into the innovation front-end must be explored. In an attempt to learn from analogous situations in which the interface between developers and customers has been managed successfully, this article analyses the Extreme Programming (XP) approach of software engineering. Through its iterative but disciplined probe-and-learn cycles, the approach helps companies effectively develop advanced products with the help of their customers. Using case studies from interviews with R&D directors of 20 technology-intensive companies, the applicability of successful practices from XP to traditional NPD is analysed. The authors identify four determinants for front-end management that reside between creativity and resource efficiency. These determinants dictate the potential for front-end effectiveness improvement and enable the maximum amount of knowledge generation and absorption from the customer.

European Validation of the Integral Code ASTEC (EVITA): First experience in validation and plant sequence calculations

The main objective of the European Validation of the In tegral Code ASTEC (EVITA) project is to distribute the severe accident integral code ASTEC to European partners in order to apply the validation strategy issued from the VASA project (4th EC FWP). Partners evaluate the code capability through validation on reference experiments and plant applications accounting for severe accident management measures, and compare results with reference codes. The basis version V0 of ASTEC ( Accident Source Term Evaluation Code)—commonly developed and basically validated by GRS and IRSN—was made available in late 2000 for the EVITA partners on their individual platforms. Users’ training was performed by IRSN and GRS. The code portability on different computers was checked to be correct. A “hot line” assistance was installed continuously available for EVITA code users. The actual version V1 has been released to the EVITA partners end of June 2002. It allows to simulate the front-end phase by two new modules: • for reactor coolant system 2-phase simplified thermal hydraulics (5-equation approach) during both front-end and core degradation phases, • for core degradation, based on structure and main models of ICARE2 (IRSN) reference mechanistic code for core degradation and on other simplified models. Next priorities are clearly identified: code consolidation in order to increase the robustness, extension of all plant applications beyond the vessel lower head failure and coupling with fission product modules, and continuous improvements of users’ tools. As EVITA has very successfully made the first step into the intention to provide end-users (like utilities, vendors and licensing authorities) with a well validated European integral code for the simulation of severe accidents in NPPs, the EVITA partners strongly recommend to continue validation, benchmarking and application of ASTEC. This work will continue in Severe Accident Research Network (SARNET) in the 6th Framework Programme where ASTEC plays a key role as the reference European integral code.

Instructional technologies in developing countries: A contextual analysis approach

This paper proposes an expanded context-based analysis approach for implementing instructional technology in developing countries by calling for the front-end analysis phase of the design process to include an analysis of the socio-cultural, environmental and institutional factors surrounding the instructional problem. Given that there is an increased application of instructional technology in developing countries and limited human capacity to appropriately design instructional technology interventions, it is imperative that instructional designers working in developing countries take into account the contextual factors outlined in the adapted Tessmer and Richey (1997) model. This adapted context-based analysis model for instructional design, if appropriately applied, may increase the probability of successful instructional technology initiatives in developing countries. Although this context-based model was expanded to include factors related to developing countries, the factors described in this paper exist in developed country settings as well. The authors would, therefore, encourage the use of this expanded model in settings that can include, but are not limited to, certain rural and urban areas in industrialized countries as well.

European validation of the integral code ASTEC (EVITA)

The main objective of the European Validation of the Integral Code ASTEC (EVITA) project is to distribute the severe accident integral code Accident Source Term Evaluation Code (ASTEC) to European partners in order to apply the validation strategy issued from the VASA project (4th EC FWP). Partners evaluate the code capability through validation on reference experiments and plant applications accounting for severe accident management (SAM) measures, and compare results with reference codes. The basis version V0 of ASTEC—commonly developed and basically validated by GRS and IRSN—was made available in late 2000 for the EVITA partners on their individual platforms. Users’ training was performed by IRSN and GRS. The code portability on different computers was checked to be correct. A “hot line” assistance was installed continuously available for EVITA code users. The actual version V1 has been released to the EVITA partners end of June 2002. It allows to simulate the front-end phase by two new modules: • for reactor coolant system two-phase simplified thermal hydraulics (five-equation approach) during both front-end and core degradation phases; • for core degradation, based on structure and main models of ICARE2 (IRSN) reference mechanistic code for core degradation and on other simplified models. Other main achievements of the project are up to now: • the EVITA validation matrix focused on main risk issues; • first validation results on PACTEL, STORM and EREC tests; • first plant applications on German 1300 PWR and VVER-440/V230.

Different alliance relationships for project design and execution

The IMEC research programme (International Programme on the Management of Construction projects) performed an extensive benchmarking study of some 60 large engineering projects around the world during the period from 1995 to 1999. The purpose of the study was to identify best practice within different areas of management of such projects. While much of the focus of the study was on the front-end phase of the projects, some aspects of project design and execution were also addressed. This paper explores the findings of the IMEC study in this respect, with an emphasis on different models for alliance relationships in the design and execution phases. A model consisting of four different configurations of the dynamics of project development and execution has been identified. Two of these are based on a traditional arms’ length relationship in the design and execution phases. These traditional relationships have been explored in numerous existing publications and are, therefore, not dealt with specifically in this paper. The two configurations displaying a relational approach in the design and execution phases, termed “partners in design and execution” and “relational development and execution”, are described in detail. Perhaps the most important finding from the study is that there is no one “best practice” or “best configuration” for managing projects—the best-suited approach is highly dependent on the project in question and its characteristics.