Environmental and economical perspectives of a glycerol biorefinery

2018 ◽  
Vol 11 (5) ◽  
pp. 1012-1029 ◽  
Author(s):  
Giacomo M. Lari ◽  
Giorgio Pastore ◽  
Moritz Haus ◽  
Yiyu Ding ◽  
Stavros Papadokonstantakis ◽  
...  
Keyword(s):  
State Of The Art ◽  
Critical Parameters ◽  
Process Assessment ◽  
Glycerol Valorisation

Process assessment uncovers most state-of-the-art glycerol-valorisation technologies as attractive, unravels critical parameters for optimisation and highlights advantages of integration within a biorefinery.

scholarly journals A STUDY INVESTIGATING CHALLENGES IN THE INTERFACE BETWEEN PRODUCT DEVELOPMENT AND MANUFACTURING IN THE DEVELOPMENT OF SOFTWARE-INTENSIVE AUTOMOTIVE SYSTEMS

2012 ◽  
Vol 22 (07) ◽  
pp. 965-1004 ◽  
Author(s):  
J. PERNSTÅL ◽  
A. MAGAZINIUS ◽  
T. GORSCHEK
Keyword(s):  
Product Development ◽  
Automotive Industry ◽  
State Of The Art ◽  
Future Research ◽  
Manufacturing Processes ◽  
Process Assessment ◽  
Automotive Systems ◽  
Extensive Analysis ◽  
Key Issues ◽  
Software Intensive

The automotive industry is facing a tremendous growth in the engineering of software-intensive systems, giving rise to various challenges. To prevent problems related to the fit of new software technologies in vehicles and the manufacturing processes, a well functioning interaction between the functions for product development and manufacturing is crucial. This is complicated by the fact that the changeable nature of software development causes unprecedented needs for collaboration and coordination between these two functions. This paper reports on a process assessment that focuses on the interface between the functions for product development and manufacturing in the development and design of software-intensive automotive systems. The main purpose of the study was to identify the key issues for improvement in the area assessed. The assessment was performed at two Swedish automotive companies where data were collected from documents and in interviews with practitioners. Nine key improvement issues were established ranging from challenges in requirements engineering to the need for knowledge transfer between manufacturing and product development. In addition, to increase the understandability of the results and map possible avenues for solution and future research, the paper provides an extensive analysis of each improvement issue in relation to the state-of-the-art.

State-of-the-Art on Deep Water Thermal Insulation Systems

2002 ◽  
Author(s):  
Frank Grealish ◽  
Iggy Roddy
Keyword(s):  
Thermal Insulation ◽  
Deep Water ◽  
State Of The Art ◽  
Syntactic Foam ◽  
Critical Parameters ◽  
Long Term Effects ◽  
Oil Companies ◽  
Insulation Materials ◽  
Insulation Systems

There are currently a wide variety of insulation systems available for deep water subsea applications. These systems are applied in a number of different configurations including externally bonded systems, pre-manufactured insulation modules that are strapped on to subsea structures and pipe-in-pipe (PIP) insulation systems. The most common insulation materials include polymers such as polyurethane, epoxies and polypropylene and for deep water applications these are used in two main forms; syntactic foam and composite syntactic foam. The limits associated with current insulation systems include lack of experience on the performance of these systems in long-term deepwater service and relatively low temperature limits when exposed to hot/wet conditions. At present, tests for assessing their thermal and physical properties are manufacturer-dependent and, for a purchaser of such systems, need to be interpreted across a range of existing and new materials and manufacturer specifications. The immediate and long-term effects of temperature, hydrostatic pressure and environmental exposure are not yet fully understood. Currently there is a lack of agreed-upon standards for insulation materials. There is a requirement in the industry for the development of consistent standards for the specification, design, materials, manufacturing and testing of insulation materials and systems. To address this requirement a Joint Industry Project (JIP) commenced in April 2000 to develop a new industry wide standard for insulation and buoyancy materials, designated the InSpec JIP. Twenty companies are participating in the JIP, including nine oil companies, eight manufacturers of insulation/buoyancy products and three contractors. This paper presents a review of the current state-of-the-art for thermal insulation systems for deep water applications. The capabilities of alternative systems are reviewed and evaluated. The key issues associated with each system type and critical parameters for the most common insulation materials are presented and discussed. The development of industry standards within the InSpec JIP to address the critical issues for qualification is highlighted within this paper.

scholarly journals The Efficiencies of Single-Stage Centrifugal Compressors for Aircraft Applications

1991 ◽  
Author(s):  
C. Rodgers
Keyword(s):  
Mach Number ◽  
State Of The Art ◽  
Single Stage ◽  
Critical Parameters ◽  
Design Parameters ◽  
Centrifugal Compressors ◽  
Design Work ◽  
Engine Design ◽  
Specific Speed ◽  
System Power

The thrust of most recent advances in single– and two–stage centrifugal compressor technology by the aerospace community has been motivated by interest in increasing airbreathing propulsion system power density, and improving specific fuel consumption with higher stage pressure ratios. Advances in the last decade have made it appropriate to review the major design parameters influencing the efficiency levels of single–stage centrifugal compressors for aircraft applications. A simple efficiency correlation was derived for advanced single–stage centrifugal compressors. It was based upon four critical parameters: • Inlet Specific Speed • Impeller Tip Diameter • Inducer Tip Relative Mach Number • Exit Discharge Mach Number The correlation was shown to predict attainable state–of–the–art efficiencies within a band width of ± 2 % points. This was considered acceptable for preliminary compressor and engine design work.

scholarly journals Highway Travel Time Prediction of Segments Based on ANPR Data considering Traffic Diversion

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Wenjun Du ◽  
Bo Sun ◽  
Jiating Kuai ◽  
Jiemin Xie ◽  
Jie Yu ◽  
...  
Keyword(s):  
Travel Time ◽  
Traffic Management ◽  
State Of The Art ◽  
The State ◽  
Attention Mechanism ◽  
Critical Parameters ◽  
Depth Information ◽  
Highway Traffic ◽  
Residual Network ◽  
Traffic Diversion

Travel time is one of the most critical parameters in proactive traffic management and the deployment of advanced traveler information systems. This paper proposes a hybrid model named LSTM-CNN for predicting the travel time of highways by integrating the long short-term memory (LSTM) and the convolutional neural networks (CNNs) with the attention mechanism and the residual network. The highway is divided into multiple segments by considering the traffic diversion and the relative location of automatic number plate recognition (ANPR). There are four steps in this hybrid approach. First, the average travel time of each segment in each interval is calculated from ANPR and fed into LSTM in the form of a multidimensional array. Second, the attention mechanism is adopted to combine the hidden layer of LSTM with dynamic temporal weights. Third, the residual network is introduced to increase the network depth and overcome the vanishing gradient problem, which consists of three pairs of one-dimensional convolutional layers (Conv1D) and batch normalization (BatchNorm) with the rectified linear unit (ReLU) as the activation function. Finally, a series of Conv1D layers is connected to extract features further and reduce dimensionality. The proposed LSTM-CNN approach is tested on the three-month ANPR data of a real-world 39.25 km highway with four pairs of ANPR detectors of the uplink and downlink, Zhejiang, China. The experimental results indicate that LSTM-CNN learns spatial, temporal, and depth information better than the state-of-the-art traffic forecasting models, so LSTM-CNN can predict more accurate travel time. Moreover, LSTM-CNN outperforms the state-of-the-art methods in nonrecurrent prediction, multistep-ahead prediction, and long-term prediction. LSTM-CNN is a promising model with scalability and portability for highway traffic prediction and can be further extended to improve the performance of the advanced traffic management system (ATMS) and advanced traffic information system (ATIS).

scholarly journals A Comprehensive Survey of Driving Monitoring and Assistance Systems

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2574 ◽  
Author(s):  
Muhammad Qasim Khan ◽  
Sukhan Lee
Keyword(s):  
State Of The Art ◽  
Critical Parameters ◽  
Road Accidents ◽  
Major Research ◽  
Driving Experience ◽  
Multiple Sensors ◽  
Research Areas ◽  
Comprehensive Survey ◽  
Assistance Systems ◽  
Comprehensive Framework

Improving a vehicle driver’s performance decreases the damage caused by, and chances of, road accidents. In recent decades, engineers and researchers have proposed several strategies to model and improve driving monitoring and assistance systems (DMAS). This work presents a comprehensive survey of the literature related to driving processes, the main reasons for road accidents, the methods of their early detection, and state-of-the-art strategies developed to assist drivers for a safe and comfortable driving experience. The studies focused on the three main elements of the driving process, viz. driver, vehicle, and driving environment are analytically reviewed in this work, and a comprehensive framework of DMAS, major research areas, and their interaction is explored. A well-designed DMAS improves the driving experience by continuously monitoring the critical parameters associated with the driver, vehicle, and surroundings by acquiring and processing the data obtained from multiple sensors. A discussion on the challenges associated with the current and future DMAS and their potential solutions is also presented.

Steganalysis

2011 ◽  
pp. 245-265 ◽  
Author(s):  
Hafiz Malik ◽  
Rajarathnam Chandramouli ◽  
K. P. Subbalakshmi
Keyword(s):  
Detection Probability ◽  
State Of The Art ◽  
The State ◽  
Critical Parameters ◽  
Secret Key ◽  
Open Problems ◽  
Message Length

In this chapter we provide a detailed overview of the state of the art in steganalysis. Performance of some steganalysis techniques are compared based on critical parameters such as the hidden message detection probability, accuracy of the estimated hidden message length and secret key, and so forth. We also provide an overview of some shareware/freeware steganographic tools. Some open problems in steganalysis are described.

scholarly journals A new laboratory for the students of the Faculty of Engineering at the University of Sherbrooke to support the characterization and the validation of their prototypes

2018 ◽  
Author(s):  
Jonathan Nadeau ◽  
Alain Desrochers ◽  
João Pedro Trovão
Keyword(s):  
Product Design ◽  
Design Process ◽  
Unique Feature ◽  
State Of The Art ◽  
Critical Parameters ◽  
Student Projects ◽  
The University ◽  
Design Experience

In order to help the students of the Faculty of Engineering at the Université de Sherbrooke within the field of product design in engineering, the Laboratory for the Characterization and the Validation of Prototypes (LCVP) has been created. The facilities feature most of the resources needed to conduct experiments toward the estimation and measurement of critical parameters and specifications along the design process but also toward the final validation of a product design. To that end the support of a professional researcher is provided to advise the students toward the proper implementation of their test benches. Overall, the LCVP provides state-of-the-art equipment and competent resources to the students from various departments at both undergraduate and graduate levels therefore improving their product design experience, while enhancing their competencies. This is indeed a unique feature of the LCVP, setting it apart from other initiatives targeted at supporting capstone and student projects.

scholarly journals Review of Factors Controlling Skid Resistance at Tire-Pavement Interface

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Abhinav Kumar ◽  
Ankit Gupta
Keyword(s):  
Road Safety ◽  
State Of The Art ◽  
Asphalt Pavement ◽  
Weather Conditions ◽  
Critical Parameters ◽  
Pavement Performance ◽  
Skid Resistance ◽  
Pavement Maintenance ◽  
Pavement Surface ◽  
Maintenance And Rehabilitation

Road safety is of prime importance for pavement engineers and maintenance authorities. Pavement resistance to skidding of the vehicle has long been recognized as one of the leading parameters governing road safety and driving comfort, especially in wet weather conditions. The knowledge of skid resistance offered by pavement surface is very valuable information for road safety enhancements. Skid resistance is defined as the force developed when a tire that is prevented from rotation slides along the pavement surface. Evaluation of skid resistance over time and estimation of factors influencing it are important for pavement maintenance and rehabilitation planning. This paper presents a state-of-the-art review of various research works carried out for assessing critical parameters like surface texture, tire tread, rain intensity, temperature, loading condition, tire inflation pressure, and pavement type which control skid resistance of asphalt pavement at tire-road interface significantly. First, a brief overview of skid resistance and its importance in asphalt pavement is provided. Then, critical parameters influencing skid resistance are identified and reviewed more elaborately. Furthermore, the key relationship between skid resistance and various controlling parameters is reviewed and presented for a better understanding of skid variation analysis. Finally, a general discussion on skid resistance governing factors, their relative importance in maintaining safety and pavement performance, the complexity involved in computation, and established relationships with skid resistance is briefly summarized.

Alarms, Shutdowns and Trip Rationalization

2021 ◽  
Author(s):  
Rasidi Mohamed ◽  
Syafeq Moazari Sukeri ◽  
Robert Mendoza ◽  
Rainer Kurz
Keyword(s):  
Control System ◽  
Gas Turbine ◽  
State Of The Art ◽  
The Other ◽  
Critical Parameters ◽  
Control Algorithms ◽  
Operating Parameters ◽  
Compressor Station ◽  
Safe Operation ◽  
Other Hand

Abstract A key function for a control system in a gas turbine train is to keep the operation of all components within a range of parameters that keep the unit safe. If the operating parameters of components fall outside the desired range for safe operation, the control system will detect these and create an alarm. For critical parameters, the control system may initiate an alarm and a shutdown of the unit. In many instances, an alarm may precede the shutdown command. Frequent discussions evolve around situations that lead to a shutdown of the train, as shutdowns impact the availability of the turbomachinery equipment, but in a wider sense also the availability of the compressor station. Therefore, shutdowns impact the profitability of a system. On the other hand, shutdowns may prevent significant, costly damage to the equipment, with significant downtime, and financial implications. In this lecture, we will discuss different methodologies for shutdown requirements, in the effort to maximize availability of units. Particular emphasis will be given to aging machines as well as machines where the instrumentation, and the control algorithms may no longer be state of the art, or where unnecessary or spurious shutdowns plague an installation.

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