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The introduction of a three-quarter-view database in the PRO-fit facial-composite system has enabled an investigation into the effects of image view in face construction. The purpose of this paper is to examine the impact of constructing full-face and three-quarter-view composites under different encoding conditions. It also examines the potential value of three-quarter-view composites that can be generated automatically from a front-view composite. The authors also investigate whether there is an identification benefit for presenting full-face and three-quarter composites together.

Three experiments examine the impact of encoding conditions on composite construction and presentation of composites at the evaluation stage.

The work revealed that while standard full-face composites perform well when all views of the face have been encoded, care should be taken when a person has only seen one view. When a witness has seen a side view of a suspect, a three-quarter-view composite should be constructed. Also, it would be beneficial for a witness to construct two composites of a suspect, one in full-face view and one in a three-quarter-view, particularly when the witness has only encoded one view. No benefit emerged for use of three-quarter-view composites generated automatically.

This is the first study to examine viewpoint in facial composite construction. While a great deal of research has examined viewpoint dependency in face recognition tasks, composite construction is a reconstruction task involving both recall and recognition. The results indicate that there is a viewpoint effect that is similar to that described in the recognition literature. However, more research is needed in this area.

The practical implications of this research are that it is extremely important for facial composite operators in the field (police operators) to know who will make a good likeness of the target. Research such as this which examines real-life issues is incredibly important. This research shows that if a witness has seen all views of a perpetrator’s face then standard composite construction using a full-face view will work well. However, if they have only seen a single view then it will not.

There are obvious wider societal implications for any research which deals with eyewitness memory and the potential identification of perpetrators.

No research to date has formally examined the impact of viewpoint in facial-composite construction.

The police often ask witnesses and victims to construct a facial composite of people they have seen committing a crime. Research has suggested, however, that these images are of poor quality due to memory decay, the face construction method used and the presence of the external facial features (hair, ears, face shape). In the current work, the role of the most important external feature, hair, was explored. Participants were shown an unfamiliar target face and constructed a composite of it 24 hours later using a modern recognition‐based system and one of three types of hair: exact, similar or poor match to the target. Better‐matching hair was found to help participants construct a more identifiable central region of the face (eyes, brows, nose, mouth). The results highlight the importance of accurate hair at the start of the construction session. Implications for police practice are discussed.

Poly‐ether‐ether‐ketone (PEEK), a specialty polymer, does not have any tribo‐utility as a bearing material in a virgin form since it exhibits quite a high coefficient of friction (μ) and stick‐slip behavior. The present paper seeks to deal with the adhesive wear behavior of series of PEEK composites based on inclusion of short fibers of glass (GF) and carbon (CF) and solid lubricants such as Polytetrafluoroethylene and graphite. The studies are focused to examine the role of these ingredients on enhancing PV limit, which is an indication of utility of a tribo‐polymer in severe operating conditions.

The Adhesive wear studies were performed on a pin on disc machine fabricated for high speed, load and temperature conditions. A composite pin slid over a disc of mild steel under two selected sliding speeds (2 and 3 m/s) for an hour. The load was varied in each experiment till the pin showed failure. The performance assessment was done based on multiple parameters such as magnitude of μ and its fluctuations with time, specific wear rate, PV limit, compatibility with the counterface, etc. PV limit was judged by observing either sudden increase in μ or wear rate (or both), deformation of the pin or change in the color of the disc.

It was observed that the neat PEEK exhibited very high and fluctuating μ with very low P‐V limit value (150 Nm/s) and high wear rate (2 × 10⁻¹⁴ m³/Nm). Inclusion of 30 percent CF benefited the strength properties but not the tribo‐performance appreciably. Composite D with a combination of GF (25 percent) and solid lubricants (30 percent) excelled in performance with a wide margin. The highest PV limit along with the lowest μ and lowest wear rate and counterface friendliness proved it to be most promising bearing material for the selected harsh operating conditions.

The composite D, which worked better than the commercial composite in almost all the selected operating conditions, indicates its commercial potential as a bearing grade material for high PV conditions.

Synergism between reinforcement and solid lubricants in right amount led to excellent friction and wear performance which was very well analysed based on worn surface topography.

The purpose of this paper is to develop hybrid aluminum metal matrix composite by stir casting process, reinforced with graphite and hard boron carbide particles to enhance the wear resistance. An attempt is made to optimize the wear (weight loss) and coefficient of friction (COF) by considering three factors, i.e. normal load, track diameter and sliding speed which were varied at three different levels.

The effect of graphite and boron carbide on microhardness was studied by adding them in varying percentages. After determining the best combination of hybrid reinforcements, optimization of wear (weight loss) and COF was carried out at various levels of considered factors. Taguchi design of experiments was used using the software “Minitab 16.1”. ANOVA was used to analyze the effect of various parameters on wear and COF. To validate the results, mathematical modeling was carried out in terms of regression equations and results obtained by regression equations.

The results revealed that the lower weight percentage of graphite (3 per cent) and boron carbide (1 per cent) significantly improved microhardness of developed composites. Results of ANOVA revealed that normal load was the main contributing factor for wear and COF. The results obtained by regression equations and confirmatory tests were within the results obtained by ANOVA.

To the best of the author’s knowledge, very less work has been reported on optimization of wear and COF using hybrid reinforcement particles of graphite and boron carbide.

The purpose of this paper is to describe four experiments evaluating post-production enhancement techniques with facial composites mainly created using the EFIT-V holistic system.

Experiments 1-4 were conducted in two stages. In Stage 1, constructors created between one and four individual composites of unfamiliar targets. These were merged to create morphs. Additionally in Experiment 3, composites were vertically stretched. In Stage 2, participants familiar with the targets named or provided target-similarity ratings to the images.

In Experiments 1-3, correct naming rates were significantly higher to between-witness 4-morphs, within-witness 4-morphs and vertically stretched composites than to individual composites. In Experiment 4, there was a positive relationship between composite-target similarity ratings and between-witness morph-size (2-, 4-, 8-, 16-morphs).

The likelihood of a facial composite being recognised can be improved by morphing and vertical stretch.

This paper improves knowledge of the theoretical underpinnings of these facial composite post-production enhancement techniques. This should encourage acceptance by the criminal justice system, and lead to better detection outcomes.

The purpose of current study deals with the development and wear testing of jute and cotton fiber reinforced with nano fly ash-based epoxy composites. Performance of waste cotton fabric nano hybrid composites are compared with waste jute fabric nano hybrid composites.

Basic hand layup technique was used to develop composites. To optimize the parameters and design of experiments, Taguchi design was implemented to test wear rate and co-efficient of friction as per ASTM standards. Performance of waste cotton fabric nano hybrid composites is compared with waste jute fabric nano hybrid composites.

Result shows that nano fly ash lowers the wear rate and co-efficient of friction in developed composites. Findings reveals that hybrid composites of waste jute Fabric with 3 Wt.% of nano fly ash performed best amongst all composites developed. Morphology of nano composites worn out surfaces are also analyzed through SEM.

Practically, textile waste, i.e. jute, cotton and nano fly ash (thermal power plant) all wastes, is used to develop composites for multi-function application.

Wastes are reused and recycled to develop epoxy-based composites for sustainable structures in aviation.

To the best of the authors’ knowledge, nano fly ash and jute, cotton combination is used for the first time to develop and test for wear application.

The purpose of this paper is to study the question of pre‐emptive merger decisions in a composite good framework where these goods have both competitive and complementary features.

The paper constructs a model of partial mergers when there are three firms and three goods in the production network, but consumers need only two goods to complete their consumption. This means, two of the firms produce two competing brands while the other firm produces any complementary product. Then under vertical merger cooperation takes place between two firms producing mutually compatible or complementary goods, whereas horizontal integration occurs when cooperating firms produce goods substitutes to each other.

In such a framework, partial mergers inflict strong negative externalities on the outside firms. The paper shows that loss of profits to the non‐integrated firm is higher under horizontal integration than that under vertical integration; hence pre‐emptive incentives for vertical merger are always larger. The paper clearly distinguishes between private incentives and pre‐emptive incentives for merger. If so desired, the vertically merged firm could foreclose the market of the outside firm and emerge as monopoly. Interestingly, foreclosing in our model is never optimal. The paper also provides a welfare analysis. While all‐firm merger maximizes social welfare, under vertical merger consumers are always better off. Industry profit also goes up if the goods are not so close substitutes.

This appears to be the first paper that discusses the question of pre‐emptive mergers in a framework of composite goods. Since, in the structure presented a horizontal merger always reduces welfare, one implication of the result is that the antitrust authority should not remain indifferent to the forms of merger actually taking place in a country.

The aim is to study the tribological behavior of dual particle size (DPS) and triple particle size (TPS) SiC reinforced aluminum alloy‐based metal matrix composites – MMCs (Al/SiC_p MMC).

Al‐MMCs with DPS and TPS of SiC were prepared using 20 wt% SiC and developed using stir‐casting process. The TPS composite consist of three different sizes of SiC and DPS composite consist of two different sizes of SiC. The tribological test was carried out using a pin‐on‐disc type tribo‐test machine under dry sliding condition.

The TPS composite exhibited better wear resistance properties compared to DPS composite. It is anticipated that when a composite is integrated with small, intermediate and large SiC particle sizes (which is known as TPS) within the same composite could be an effective method of optimizing the wear resistance properties of the developed material.

This study provides a way to enhance the tribological behavior of automotive tribo‐components such as brake rotor, piston, cylinder, etc.

This investigation compares the tribological behavior of DPS and TPS SiC reinforced aluminum MMCs.

Research suggests that memory for unfamiliar faces is pictorial in nature, with recognition negatively affected by changes to image-specific information such as head pose, lighting and facial expression. Further, within-person variation causes some images to resemble a subject more than others. Here, the purpose of this paper is to explore the impact of target-image choice on face construction using a modern evolving type of composite system, EvoFIT.

Participants saw an unfamiliar target identity and then created a single composite of it the following day with EvoFIT by repeatedly selecting from arrays of faces with “breeding”, to “evolve” a face. Targets were images that had been previously categorised as low, medium or high likeness, or a face prototype comprising averaged photographs of the same individual.

Identification of composites of low likeness targets was inferior but increased as a significant linear trend from low to medium to high likeness. Also, identification scores decreased when targets changed by pose and expression, but not by lighting. Similarly, composite identification from prototypes was more accurate than those from low likeness targets, providing some support that image averages generally produce more robust memory traces.

The results emphasise the potential importance of matching a target's pose and expression at face construction; also, for obtaining image-specific information for construction of facial-composite images, a result that would appear to be useful to developers and researchers of composite software.

This current project is the first of its kind to formally explore the potential impact of pictorial properties of a target face on identifiability of faces created from memory. The design followed forensic practices as far as is practicable, to allow good generalisation of results.

The purpose of this paper is to review research studies on process optimisation and machine development that lead to the enhancement of final products in various aspects of the fused deposition modelling (FDM) process.

An overview of the literature, focussing on process parameters, machine developments and material characterisations. This study investigates recent research studies that studied FDM capabilities in printing a vast range of materials from thermoplastics to metal alloys.

FDM is one of the most common techniques in additive manufacturing (AM) processes. Many parameters in this technology have effects on three-dimensional printed products. Therefore, it is necessary to obtain the optimum elements, for example, build orientation, layer thickness, nozzle diameter, infill pattern and bed temperature. By selecting a proper variable range of parameters, the layers adhere strongly and building end-use products of high quality are achievable. A vast range of materials and their properties from polymers to composite-based polymers are presented. Novel techniques to print metal alloys and composites are examined to increase the productivity of the FDM process. Additionally, defects such as shrinkage and warpage are discussed to eliminate the system’s limitations and improve the quality of final products. Multi-axis and mobile machines brought enhancements throughout the process to eliminate obstacles such as staircase defects in the conventional FDM process. In brief, recent developments were identified and a summary of major improvements was discussed in this study for future research.

This paper is an overview that provides information about research and developments in FDM. This review focusses on process optimisation and obstacles in printing polymers, composites, geopolymers and novel materials. Therefore, machine characteristics were examined to find out the accessibility of printing novel materials for different applications.