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The purpose of this study is to investigate labor congestion in the automotive industry in Mexico.

By using the cluster and subcluster definitions by Delgado et al. (2016) and relying on an efficiency and production function perspective, this study estimates a standard production function and measures marginal returns of labor at the regional cluster and subclusters levels. To assess whether wages affect the finding of congestion and productivity, the model also measures the individual impact of wages on both total productivity and marginal returns of labor.

Among other results, this paper finds evidence of labor congestion in the automotive cluster in Mexico. This congestion deepens with wages and it is specific to some regions and some subclusters.

The methods used are based on panel data techniques but are fundamentally cross-section in nature. The time period available may condition these findings.

To the authors’ knowledge, this is the first study reporting congestion in the automotive cluster in Mexico.

The purpose of this paper is to present results of practical experience of cold starting a gasoline engine on low volatility fuel suitable for unmanned aerial vehicle (UAV) deployment.

Experimental research and development is carried out via dynamometer testing of systems capable of achieving cold start of a spark ignition UAV engine on kerosene JET A-1 fuel.

Repeatable cold starts have been satisfactorily achieved at ambient temperatures of 5°C. The approximate threshold for warm engine restart has also been established.

For safety and supply logistical reasons, the elimination of the use of gasoline fuel offers major advantages not only for UAVs but also for other internal combustion engine-powered equipment to be operated in military theatres of operation. For gasoline crankcase-scavenged two-stroke cycle engines, this presents development challenges in terms of modification of the lubrication strategy, achieving acceptable performance characteristics and the ability to successfully secure repeatable engine cold start.

The majority of UAVs still operate on gasoline-based fuels. Successful modification to allow low volatility fuel operation would address single fuel policy objectives.

Although China can be considered an early adopter of the circular economy, there are few studies of remanufacturing business models (BMs) in the context of the Chinese automobile industry. The purpose of this paper is to investigate viable BMs, summarizes current obstacles and anticipates future development opportunities and directions.

The cross-case analysis considers the roles of value networks and of customer value proposition and interface in circular business models (CBMs) by examining the strategies and tactical measures of two leading remanufacturers. The data are collected from semi-structured interviews, documents, etc.

The analysis identifies the following components of viable BMs of remanufacturers: reclaiming raw material, managing used components, producing new products and marketing. Several current obstacles are summarized from four perspectives: policy barriers and insufficient government support; consumer awareness; related product quality; and technology. The study also identifies future directions and opportunities for the automobile parts remanufacturing industry.

This study contributes to the CBM literature by mapping the barriers and opportunities in remanufacturing. The results have shed some light into the field of sustainability in manufacturing firms by empirically testing the theoretical model. The results will help managers to design viable CBMs in different contexts.

AUTOMOTIVE engine designers will know that the oil film in a plain bearing system has three duties: it converts energy into heat, supports the load, and separates the relatively moving surfaces.

The aim of this paper is to solve the problem of carbonaceous deposits in automotive engines by preparing different ashless detergent/dispersant additives based on propylene oxide (PO) and different amines. Carbonaceous deposits in automotive engines are the major problems associated with oil aging. Efficient detergents and dispersants have been used to solve this problem, particularly in lubricating oils.

The structures of the prepared compounds were confirmed using Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR) and gel permeation chromatography (GPC) for determination of molecular weight. This was followed by the evaluation of the prepared compounds such as detergent/dispersant and antioxidants additives for lubricating engine oil using several techniques such as variation of viscosity ratio, change in total acid number, optical density using infrared techniques, spot method, determination of sludge and determination the potential detergent dispersant efficiency (PDDE).

All the prepared compounds were found to be soluble in lubricating oil. The efficiency of the prepared compounds such as antioxidant and detergent/dispersant additives for lubricating oil was investigated. It was found that the additives have excellent power of dispersion, detergency and the most efficient additives such as antioxidant those prepared by using n,n-dimethyloctadecylamine (NDOA) and di-n-butyl dithio phosphoric acid.

The paper includes preparation of new compounds from the reaction of propoxylated amines and different organic acids and evaluates them as detergent/dispersant and antioxidants additives by using several techniques.

This paper fulfils an identified need to prepare new compounds from the reaction of propoxylated amines and different organic acids and evaluates them as additives by using different methods. All were found to have better efficiency as compared with commercial additives.

A new sensor has been developed which will enable engine pressure data to be available at a cost suitable for the average production vehicle. Unlike many previous devices this sensor will be suitable for the harsh environmental conditions of production vehicles themselves and not just the test environment. The sensor is small, extremely rugged and has a sufficiently wide bandwidth to be easily able to detect engine problems such as pre‐ignition, miss‐fire and malfunctioning engine components. Furthermore, the patented sensor technology does not require expensive electronic interfaces, but can use simple low‐cost off the shelf components. The sensor's performance and limitations are discussed, based on real data from a single cylinder petrol engine. An analysis of the sensor output signals, showing both time and frequency domain data under varying load conditions, is also included.

A mathematical tool for the fuzzy identification of a system is presented. This hybrid mathematical method combines the fuzzy description of input space and the description of input‐output relations using the Bézier interpolation technique. This is a computationally simple method for designing a curve(surface). Its efficiency is expressed in its powerful application in controlling the shape of a described curve (surface), both simplifying the determination of the parameters of input‐output relations, qualititively by precision and quantitatively by decreasing the number of control points (values) required. Shows an application of the method to computer‐aided identification of the steady‐state operating points of a thermal engine.

This paper is concerned with three types of bearing applications:

Discusses the properties of various asbestos‐free gasket materials, in particular expanded PTFE. Presents the factors which need to be taken into account when choosing a gasket. Highlights the requirements of gaskets in the automotive industry and the conditions they have to withstand.