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This paper proposes a framework for knowledge integration in a complex product development setting, using case studies from large-scale manufacturing enterprises in the U.S. defense aerospace industry. The framework highlights the main channels and mechanisms used most frequently in different technical problem-solving situations. We conclude that, in view of the varying complexity of the technical problems that product development teams typically face, they would be advised to establish and use particular knowledge integration channels, and to adopt particular knowledge integration mechanisms, in order to address effectively the complexity of the particular problems they face in practice.

The electrification of public transport buses is getting more insights, especially in urban areas. The use of Battery electric buses (BEB) results in no tailpipe emissions, which gives BEB an advantage over diesel, hybrid and natural gas buses. However, the high capital costs and fluctuating operating costs of BEB limits their market breakthrough. Minimizing the total costs of BEB is essential to ease their deployment and this can be achieved by optimally designing the battery size and managing the charging strategy of the buses. These costs incur significant fluctuations as they are highly sensitive to electricity tariffs set by local authorities. In addition, these costs are directly driven by the battery costs, battery technology, and onboard energy management. For this sake, it is essential to evaluate the effect of the mentioned parameters on BEB optimal battery sizing and charging strategy and highlight their impact on the electricity grid

Battery electric buses (BEB) are being recognized as a promising solution to replace diesel bus fleets. However, this technology is still subject to many challenges, namely the limited driving range and high total cost of ownership. Besides, BEB energy costs are subject to high fluctuations depending on the electricity generation mix and local electricity tariffs. This paper proposes an optimization algorithm based on Dynamic Programming that minimizes the total BEB energy costs and battery replacement costs by optimally controlling the BEB daily charging power throughout the year, considering the varying operating conditions. The algorithm is illustrated in the case of bus number 21 in Paris.

Lebanon's road transportation sector is one of the most unsustainable in the Middle East region due to the exclusive reliance on conventional engine vehicles for passenger mobility and freight. Previous studies showed that significant reductions in energy use and emissions can be achieved from combining mitigation strategies that improve engine technology for cars and increase the use of public transport. However, these are not sufficient to offset the growth in freight emissions, estimated to account for nearly half of total GHG emissions in 2040. Therefore, this study uses system dynamics modeling to estimate the potential reductions of fuel use and CO2 emissions from cleaner electrified truck technologies, combined with using electric rail for heavy freight transport. Modeling results showed potential reductions of 38% to 49% in 2040 compared to the baseline no-action scenario, depending on the share of electric light duty trucks. This can counter the significant growth trends from freight transport, as needed to transition the entire transportation sector in Lebanon to a more sustainable future.

The drive to ban diesel vehicles is well underway in several major European cities with the aim of improving air quality and reducing greenhouse gas emissions, and similar plans have been announced by authorities around the world. This poses a major challenge for the public transport sector given its high reliance on diesel bus technology. Zero-emission battery electric buses (BEB) currently stands as one of the most promising solutions for reducing the overall carbon footprint of public transport, especially with the continuous improvements in electric powertrain and battery technologies and costs. This paper presents a detailed comparative energy assessment between BEB and diesel buses (DB) operating at various driving and weather conditions. The different energy loads encountered in bus operation, including those needed for traction, air conditioning and operation of other electric, hydraulic and pneumatic auxiliaries are all considered in this study. Simulation results show that BEB consumes 2-4 times less energy compared to DB depending on the operating conditions where almost 80% of the energy saving is obtained from the reduction in the traction load.

Standards for fuel consumption and carbon dioxide emissions are implemented worldwide in most light-duty vehicle markets. Regulatory drive cycles, defined as specific time-speed patterns, are used to measure levels of fuel consumption and emissions. These measurements should realistically reflect real world driving performance, however there is increasing concern about their adequacy due to the discrepancies observed between certified and real world consumption and emissions values. One of the main reasons for the discrepancy is that current testing protocols do not account for non-mechanical vehicle energy needs, such as passengers’ thermal comfort needs and the use of electric auxiliaries on-board. Cabin heating and cooling can especially lead to considerable increase in vehicle energy consumption. This paper presents a simulation-based assessment framework to account for the additional fuel consumption related to the cabin thermal energy and auxiliary needs under the worldwide-harmonized light vehicles test procedure (WLTP). A vehicle cabin model is developed and the thermal comfort energy needs are derived for cooling and heating, depending on ambient external temperature under cold, moderate and warm climates. A modification to the WLTP is proposed by including the generated power profiles for thermal comfort and auxiliary needs. Dynamic programming is used to compute the fuel consumption on the modified WLTP for a rechargeable series hybrid electric vehicle (SHEV) architecture. Results show consumption increases of 20% to 96% compared to the currently adopted WLTP, depending on the considered climate.

This study investigates the potential reductions in energy use, greenhouse gas and pollutant emissions from natural gas, hybrid and battery electric buses compared to diesel bus in real driving conditions in Lebanon, a developing country of the Middle East with an unsustainable road transportation system. A Euro V compliant 12-meter bus is considered in the modelling, and appropriate real driving cycles are developed for four operating conditions including severe congestion, peak, off-peak and bus rapid transit operation. Results show that accounting for additional energy consumption from the use of climate control auxiliaries can significantly impact the performance of all bus technologies in this context, by 26.4% for compressed natural gas bus and up to 45% for parallel-hybrid electric bus. The energy consumption and environmental performance of all fuel bus technologies improve considerably in free-flowing traffic conditions, making bus rapid transit operation the most beneficial. Battery electric buses are found to be the best performers in all traffic conditions, conditional on having a clean energy supply at the power plants. Compressed natural gas buses do not provide significant GHG emission savings compared to diesel bus, but offer substantial reductions in the emission of harmful pollutants.

This study assesses the tank-to-wheel savings in fuel consumption and CO2 emissions as well as vehicle ownership and operating costs of electrified versus conventional midsize passenger vehicles in real-world driving conditions of the greater area of Beirut, Lebanon. This was done by developing representative driving cycles for typical home-to-work commutes during peak and off-peak traffic conditions based on an on-road travel survey. Results show that micro-hybrids are beneficial only in peak times, reducing consumption by 18.3%. Electrified vehicles provide substantial savings of 38.7% for hybrids and 88.6% for plug-in hybrids. However, plug-in and battery electric vehicles are found to contribute significant well-to-tank CO2 and pollutant emissions due to the dirty electricity mix in Lebanon. In addition, we find that the use of thermal comfort auxiliaries in congested traffic significantly reduces performance of electrified vehicles. Finally, an analysis of vehicle ownership and operating costs is done for the case of Lebanon and results show that hybrid electric vehicles are the preferred technology at low gasoline prices, while plug-in hybrids with a low electric range capability of 20 km become the most competitive at medium to high gasoline prices.

Road transportation worldwide is undergoing a rapid transition to more sustainable alternative fuel vehicle technologies as an effective means of dealing with climate change and related challenges. Several well-to-wheel studies have been done in mostly industrialized countries to assess the environmental impacts of these technologies as compared to conventional fuel vehicles. This study is a well-to-wheel assessment for the case of Lebanon and similar fuel-importing countries in the developing world where energy and transportation infrastructure are typically underdeveloped. The study considers the energy use, GHG and criteria pollutant emissions and economic costs for conventional and potentially feasible alternative fuel vehicle pathways for the Lebanese case in order to inform transition strategies to alternative fuels over the near, medium and long-terms. Results show that electric vehicles are beneficial for the long term as they require costly charging infrastructure and a clean electricity mix. Plug-in hybrid electric vehicles are attractive for the medium term, with gasoline or diesel hybrid electric vehicles the most feasible and beneficial technologies in the short-term. A sensitivity analysis showed that natural gas-based vehicles are competitive at high driving mileage, while locally produced biodiesel from waste cooking oil proved beneficial if emission controls are enforced.

The land transportation network in Lebanon faces continuing and wide-ranging challenges at the level of infrastructure development, planning and overall system management. These challenges are already significant enough to seriously hamper the network's ability to deliver an acceptable level of service within reasonable norms for environmental, health and safety impacts, especially in and around the country's major urban centers. This reality makes the road transport system in Lebanon one of the most unsustainable in the region, and as such a key candidate for closer assessment. In this paper we present a detailed case study of the passenger road transport system in the Greater Beirut Area (GBA) where we identify the root causes of the major problems facing the system today and over the long-term. We propose a framework of corresponding mitigation options as a roadmap for improving the sustainability of the system, namely by reducing the reliance on fossil fuels, decreasing pollutants and Greenhouse Gas (GHG) emissions, reducing mobility costs and increasing passenger safety.

The development of complex products requires widespread knowledge interactions among a significant number of individuals and teams designing numerous interrelated components. Increasing product complexity typically leads to a corresponding increase in the types and sources of knowledge that need to be tapped during development, and a common strategy for managing product complexity is to outsource parts and components to external suppliers. As a result, the knowledge required for development is increasingly specialized and distributed across multiple boundaries spanning large-scale organizational networks, thus requiring the subsequent integration of this knowledge in order to accomplish the development task. A framework for knowledge integration in the development of complex systems in a large-scale organizational context is proposed in this thesis using an extensive review of the pertinent literature. The framework consists of the main channels, strategies, practices and mechanisms most commonly used to transfer, share and apply knowledge in the course of complex technical problem solving. The framework is progressively refined using empirical data collected through several rounds of interviews and a questionnaire instrument administered across three major aircraft programs in the defense aerospace industry. We find that knowledge integration in routine problem solving situations is most efficiently and effectively accomplished through extensive transfer and sharing of codified information using formal mechanisms such as information systems, while knowledge integration for major non-routine troubleshooting events requires extensive integration of individual expertise and know-how through both formal and informal advice sharing as well as direct assistance across internal and external organizational boundaries. A principal contribution of this research is in demonstrating how different characteristics of the engineering artifact defined in terms of product complexit

Knowledge integration is an emerging discipline in organizational science where the central proposition is that the increasing complexity of products and services being developed and delivered, means that the knowledge required for production is increasingly specialized, varied (multi-disciplinary) and distributed across the organization’s internal boundaries, and as a result there is a need for organizations to continuously gather their knowledge resources in order to maintain their ability to innovate, and to sustain their competitive position in the market. In addition, the increasing scale and scope of organizational arrangements, such as multinational partnerships or multi-tiered prime-supplier arrangements commonly encountered in the aerospace, automotive and other complex product development industries, also give rise to environments of dispersed knowledge resources, thus necessitating the subsequent integration of this knowledge across external boundaries spanning large-scale organizational networks. Knowledge integration in this context is done through a process of transferring knowledge from multiple sources in the organizational network to where it is needed, combining it with existing knowledge, before it can be applied to accomplish complex tasks and to solve major problems. The primary purpose of this paper is to define the powerful concept of knowledge integration in large-scale organizational networks using an extensive review of the pertinent literature on knowledge in organizations. An operational definition for knowledge integration is also proposed, followed by a systematic identification and classification of the different strategies, practices, channels and mechanisms for integrating different types of knowledge across a multitude of organizational boundaries and environments.

Student research poster description sheet

Student research poster

Student research poster

Knowledge integration is an emerging discipline in organizational science where the central proposition is that the increasing complexity of products and services being developed and delivered, means that the knowledge required for production is increasingly specialized, varied (multi-disciplinary) and distributed across the organization’s internal boundaries, and as a result there is a need for organizations to continuously gather their knowledge resources in order to maintain their ability to innovate, and to sustain their competitive position in the market. In addition, the increasing scale and scope of organizational arrangements, such as multinational partnerships or multi-tiered prime-supplier arrangements commonly encountered in the aerospace, automotive and other complex product development industries, also give rise to environments of dispersed knowledge resources, thus necessitating the subsequent integration of this knowledge across external boundaries spanning large-scale organizational networks. Knowledge integration in this context is done through a process of transferring knowledge from multiple sources in the organizational network to where it is needed, combining it with existing knowledge, before it can be applied to accomplish complex tasks and to solve major problems. The primary purpose of this paper is to define the powerful concept of knowledge integration in large-scale organizational networks using an extensive review of the pertinent literature on knowledge in organizations. An operational definition for knowledge integration is also proposed, followed by a systematic identification and classification of the different strategies, practices, channels and mechanisms for integrating different types of knowledge across a multitude of organizational boundaries and environments.

Presentation on integrating the lean enterprise

Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, 2008., Includes bibliographical references (p. 238-248)., The development of complex products requires widespread knowledge interactions among a significant number of individuals and teams designing numerous interrelated components. Increasing product complexity typically leads to a corresponding increase in the types and sources of knowledge that need to be tapped during development, and a common strategy for managing product complexity is to outsource parts and components to external suppliers. As a result, the knowledge required for development is increasingly specialized and distributed across multiple boundaries spanning large-scale organizational networks, thus requiring the subsequent integration of this knowledge in order to accomplish the development task. A framework for knowledge integration in the development of complex systems in a large-scale organizational context is proposed in this thesis using an extensive review of the pertinent literature. The framework consists of the main channels, strategies, practices and mechanisms most commonly used to transfer, share and apply knowledge in the course of complex technical problem solving. The framework is progressively refined using empirical data collected through several rounds of interviews and a questionnaire instrument administered across three major aircraft programs in the defense aerospace industry. We find that knowledge integration in routine problem solving situations is most efficiently and effectively accomplished through extensive transfer and sharing of codified information using formal mechanisms such as information systems, while knowledge integration for major non-routine troubleshooting events requires extensive integration of individual expertise and know-how through both formal and informal advice sharing as well as direct assistance across internal and external organizational boundaries., (cont.) A principal contribution of this research is in demonstrating how different characteristics of the engineering artifact defined in terms of product complexity, architecture and technology newness, and different aspects of problem solving including problem type and novelty, drive the knowledge integration process and the organizational system. We conclude that permeability of cross-program boundaries, direct relationships with functional groups and rich tacit knowledge flow from suppliers are critical for countering rampant firefighting in complex product development., by Marc George Haddad., Ph.D.