Promoting biofuels: the case of ethanol blending initiative in India

Clean Technologies and Environmental Policy - In India, a gradual shift from fossil fuels to renewable fuels is considered necessary in view of growing energy demands of road transportation sector...     

Life cycle assessment of ethanol production in a rice-straw-based biorefinery in India

Clean Technologies and Environmental Policy - This work presents detailed life cycle assessment (LCA) of a novel process to produce ethanol from rice straw in India. The process has been...     

Economics of sugar production: a case study

The manufacture of sugar from crushed sugar-cane involves processing through a number of stages. The yield of crystalline sugar per unit of processed juice depends on a variety of process parameters. Increased yield is also related to the determination of a suitable mix of in-process ingredients. In this paper a case study is presented where the use of product mix has been made. The product mix in this case is arrived at by considering the profit motive of the entrepreneur and keeping in view the constraints imposed by the processing times at various stages and the capacities of the equipment at each stage. The problems of implementation of the proposed product mix were then explored and a suitable production schedule has been suggested taking into consideration certain important constraints imposed by the Indian environment.     

An integrated lignocellulosic biorefinery design for nanomaterial and biochemical production using oil palm biomass

Clean Technologies and Environmental Policy - Oil palm empty fruit bunch (EFB) biomass valorisation for high-value applications has been a current focus in research due to the vast amount of...     

木质纤维原料制乙醇原料预处理技术

从预处理的必要性出发,论述了木质纤维原料的预处理技术,分析了主要预处理技术的特点和处理纤维质原料的效果,并对未来预处理技术的发展方向提出了建议,供从事木质纤维素制乙醇的研究人员参考。     

Robust design of a spindle motor: a case study

Robust design is the process of minimising variability of products and processes in order to improve their quality and reliability. In recent years, it has seen wide spread application in many fields such as mechanical [J Quality Technol 24 (1992) 22], chemical [Quality Engng 9 (1997) 391] and civil [Quality Engng 9 (1997) 441] engineering. As an additional application, this paper investigates the use of robust design techniques during early design process, in order to predict, analyse and improve quality and reliability of spindle motors found within hard disks. The spindle motor is an integral component of the hard disk that rotates the recording media. Constant speed rotation is an absolute necessity for accurate reading and recording of information. However, it is difficult to achieve this due to the effects of cogging torque. In this paper, the robust design of a spindle motor is attempted. The motor was modelled using multiple regression analysis. A dual response approach [J Quality Technol 22 (1990) 38] was then used. This performed a constrained minimisation of the mean of the cogging response, the constraint being that the variance be within a specified limit. The results showed that the current operating point was near optimal. However, the redesign was still able to achieve a 4% and 25% reduction in the mean and the variance of the cogging torque, respectively, before actual prototypes were made.     

Research output in pheromone biology: a case study of India

Analyses the growth and development of pheromone biology research productivity in India in terms of publication output as reflected in Science Citation Index (SCI) for the period 1978–2008. It includes 330 publications from India, including 285 articles, 22 notes, 18 reviews, 4 letters and 1 conference paper, from 200 institutions. About 9.4 % of publications is contributed by Indian Institute of Technology, Kanpur followed by Bhabha Atomic Research Centre, Bombay (7.27 %). All the papers published by Indian researchers have appeared in journals with impact factors between 0.20 and 4.14. About 24.24 % of authors contributed single articles. The growth rate of publications varied from 0.30 to 9.09 % per year. The annual growth rate was highest in the year 2006 at 9.09 %. The study reveals that the output of pheromone biology research in India has gradually increased over the years.     

Implications of automation in engineer-to-order production:a case study

In order to retain a certain level of production in Norway,suppliers to the Norwegian maritime industry need to lower their production costs.Automation is generally an effective way of achieving this in standardized high-volume,low variety production.However,manufacturing companies in the Norwegian maritime industry typically supply capital-intensive,advanced and customized products in low volumes.In this engineer-to-order production situation,manual labor is traditionally preferred over automation.Nonetheless,such companies increasingly automate parts of their production.This paper presents a case of a supplier that has chosen to automate its welding operations,the implications and determinants of this decision.     

Decision monotonicity in incremental design: A case study of design for manufacture

Design has often been described as searching the space of solutions to a given problem for either a feasible or optimal solution. Usually, this search is conducted in an incremental, iterative manner. Unfortunately, there is a tendency for the feasible space in some domains to exhibit such poor structure that the incremental design process becomes both difficult and time consuming. This is especially true in the domain of design-for-manufacture by machining. In this paper we present the view that in such cases the sources of ill-structure must be aggressively eliminated by making strategic improvements and modifications to the target technology. To illustrate this point, we show that the domain of design-for-manufacture is ill-structured due to a class of interactions known as global interactions. We then show how global interactions can be virtually eliminated by a combination of a new workholding technology and a new interfacing technique. In the absence of global interactions, we show how the design structure exhibits a property of monotonicity. We describe the ramifications of this monotonicity on the design process, and show how design can then be considered to be deterministic. As a backdrop, we draw examples from other fields where similar strategies have resulted in greater designability.     

A case study in productivity-cost trade-off in the design of paced parallel production systems

This paper examines the investment and operational cost differences between high-volume serial CNC-based machining lines and parallel CNC-based machining lines. With the progress of CNC technology and their descending cost, more CNC machines have been used in high-volume production systems. CNC machines increase the flexibility and machining capability of production lines, greatly increasing the number of line configurations. Parallel configurations improve system throughput and have the same effect as adding buffers to a pure serial line but without additional work-in-process inventory. This analysis is performed through a case study of a CNC-based automotive cylinder head machining line. Examining machine reliability, line balance, configuration throughput, and cost yields insight into the cost-benefit tradeoff of implementing parallelism. It is found that even with large increases in investment in automated material handling, parallel configurations can yield significant annual cost savings over pure serial lines through reductions in capital investment, especially in CNC machines, and improvements in efficiency, and on a per unit capacity basis, parallel configurations are the least expensive.     

Application of a systematic design methodology: an engineering case study

The basic steps of a design process have been reviewed and applied to seek an optimum solution for an industrial design problem. The problem was about a mechanical swivel-joint in a sea-current-metering system for underwater marine use. It was expensive ($200) and not functioning properly because of rattling and high friction between parts. The objective was to design another joint of better performance and lower cost, if possible. Ten steps were defined and carefully followed to solve the problem. This led to the design and production of a good quality swivel-joint as far as performance, appearance and other aspects were concerned and the cost reduced by 40%. This design method, in addition to yielding good results, is suitable for the organization of the activities of new designers and design students.     

A study of the design of a lot production system.

A lot production system is, generally, adopted in the fabrication shop, which supplies the components for the following assembly line. In such a shop, it is required to supply the components for the following assembly lino without tardiness and to reduce the in-process inventory

In this paper, we analyse the relations between the number of set-ups, the lead time, the total elapsed time, the in-process waiting time and the tardiness time on two-stage multi-item models, and propose a procedure to determine the number of set-ups and the lead time.     

Multi-criteria fuzzy decision support for conceptual evaluation in design of mechatronic systems: a quadrotor design case study

Designing mechatronic systems is known to be a very complex and tedious process due to the high number of system components, their multi-physical aspects, the couplings between the different domains involved in the product, and the interacting design objectives. This inherent complexity calls for the crucial need of a systematic and multi-objective design thinking methodology to replace the often-used sequential design approach that tends to deal with the different domains and their corresponding design objectives separately leading to functional but not necessarily optimal designs. Thus, a new approach based on a multi-criteria profile for mechatronic systems is presented in this paper for the conceptual design stage. Additionally, to facilitate fitting the intuitive requirements for decision-making in the presence of interacting criteria, three different methods are proposed and compared using a case study of designing a vision-guided quadrotor drone system. These methods benefit from three different aggregation techniques such as Choquet integral, Sugeno integral and fuzzy-based neural network. To validate the decision yielded by the results of global concept score for each aggregation methods, a computer simulation of a visual servoing system on all design alternatives for quadrotor drone has been performed. It is shown that although the Sugeno fuzzy can be a useful aggregation function for decisions under uncertainty, but the approaches using Choquet fuzzy and fuzzy integral-based neural network seem to be more precise and reliable in a multi-criteria design problem where interaction between the objectives cannot be overlooked.     

Life cycle cost analysis of natural indigo dye production from Indigofera tinctoria L. plant biomass: a case study of India

Clean Technologies and Environmental Policy - The emerging demand of natural indigo dye due to the environmental and sociological concerns imparted by the synthetic dye helps in leveraging the...     

Cargo scheduling decision support for offshore oil and gas production: a case study

Woodside Energy Ltd (Woodside), Australia’s largest independent oil and gas company, operates multiple oil and gas facilities off the coast of Western Australia. These facilities require regular cargo shipments from supply vessels based in Karratha, Western Australia. In this paper, we describe a decision support model for scheduling the cargo shipments to minimize travel cost and trip duration, subject to various operational restrictions including vessel capacities, cargo demands at the facilities, time windows at the facilities, and base opening times. The model is a type of non-standard vehicle routing problem involving multiple supply vessels—a primary supply vessel that visits every facility during a round trip taking at most 1 week, and other supply vessels that are used on an ad hoc basis when the primary vessel cannot meet all cargo demands. We validate the model via test simulations using real data provided by Woodside.     

Hydrogen production from pyrolysis oil using the steam-iron process: a process design study

The overall energy efficiency of the production of pure hydrogen using the pyrolysis oil driven steam-iron process is evaluated for different process conditions. The process consists of a two-step process (reduction with pyrolysis oil, oxidation with steam) from which pure hydrogen can be obtained, without purification steps. An optimum energy efficiency of 53% is achieved when the equilibrium conversion is obtained in the redox cycle at 800°C. When assuming chemical equilibrium, increasing the process temperature results in a low process efficiency due to a large amount of unreacted steam that needs to be condensed to separate the hydrogen product. Using experimental data in the process simulation, a high-energy efficiency is obtained at 920°C (39%) compared with the efficiency at 800°C (29%). This is caused by the low conversion in the reduction at 800°C. Improving the iron oxide material to enhance the reduction with pyrolysis oil at 800°C, is therefore suggested.     

Improving the process quality using statistical design of experiments: a case study.

A technique known as Statistical design of experiments is a powerful technique for process characterization, optimization, and modeling. It has been widely accepted in manufacturing industry for improving product performance and reliability, process capability, and yield. This article illustrates the application of statistical design of experiments based on the Taguchi approach in a certain company that manufactures electromagnetic clutch coils. The objective of the study was to improve the quality of the existing process and thereby achieve heightened customer satisfaction for the product. An eight-trial experiment was conducted with the aim of reducing the number of rejects from the process. The expected savings per month was estimated to be over $11,500. The results of the study have provided a greater stimulus for the wider application of statistical design of experiments in other core processes within the company.     

Public involvement in environmental impact assessment: a case study of hydro development in Kullu District,Himachal Pradesh,India

The Governments of India and the Indian state of Himachal Pradesh (HP) recently adopted policy changes intended to expedite development approvals for power projects. This paper focuses on the 1997 changes to the Environmental Protection Act that establish procedures for public hearings as a component of EIA. Three hydro project public hearings in the Kullu District (HP) in 1998 show that public involvement andpublic hearing processes are in their nascent stages despite the rapid pace of development. Many constraints, such as inaccessibility of information, lack of familiarity with EIA, and lack of institutional capacity, hinder serious public involvement. Public concerns focused on safety issues (blasting), new road construction and jobs, with little consideration of environmental impact.     

Analysis and modelling of intertemporal relationships in lifecycle design: a case study for investment goods

The relevance of integrating the features of product operation and disposal in product design is growing very strongly in the business-to-business sector, as the purchasers of long-life products increasingly base their buying decision on a lifecycle ??prism??. Within the lifecycle several relationships exist, which may be of oppositional or complementary nature and face the designer with the problem of making decisions crucial to the entire lifecycle. This paper suggests an approach to modelling several cost interdependencies between different lifecycle stages, as available models of lifecycle design do not include these relationships. This developed approach was validated in a case study focused on the design improvement of an investment good aiming at the lowering of operating costs. The case study confirms the structure of the modelled relationships and delivers the first detailed analysis of the relationship between design costs and operating costs.