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The purpose of this paper is to improve an image defogging algorithm based on a dark channel prior and use this method to clear the foggy image on the Advanced RISC (Reduced Instruction Set Computing) Machines (ARM) platform.

The divided strategy of the foggy image was proposed through the estimation of the brightness and transmission thresholds. The two regions of the foggy image were processed using two transmissions. Many foggy images were tested using the improved method.

The finding resulting from this study is that a divided strategy has been proposed to use the image defogging. Compared with the existing methods, the running time of the improved method is less on the ARM platform.

Image enhancement is an important technology of digital images, and the quality of images plays a key role in the video monitoring and the intelligent transportation system.

This paper presented an improved image defogging method using the divided strategy and a substantial number of experimental results was provided to demonstrate this method.

In the information commons (IC) space of library, it is very important to recognize the emotional state of users for better playing the role of IC. In view of this point, this paper aims to discuss the human expression of user emotion.

An emotional state recognition method based on body posture change under video monitoring is proposed. In this method, two parameters are proposed to represent the emotional state of users. Finally, the distribution of users’ overall emotional state is recognized.

It is found that the change of human posture reflects the emotional state of users to a certain extent. The spatial frequency of the user’s average body position change and per capita body position change can reflect the spatial distribution of individual and body position change, respectively.

The method in this paper can effectively overcome the inaccuracy of manual identification of video monitoring images, especially in the case of a large number of users and effectively help the construction of university library IC space and provide a basis for the setting of environmental parameters.

To face the challenges raised by the high incidence of falls among older adults, the intelligent video-monitoring system (IVS), a fall detection system that respects privacy, was developed. Most fall detection systems are tested only in laboratories. The purpose of this paper is to test the IVS in a simulation context (apartment-laboratory), then at home.

This study is a proof of concept including two phases: a simulation study to test the IVS in an apartment-laboratory (29 scenarios of activities including falls); and a 28-day pre-test at home with two young occupants. The IVS’s sensitivity (Se), specificity (Sp), accuracy (A) and error rate (E) in the apartment-laboratory were calculated, and functioning at home was documented in a logbook.

For phase 1, results are: Se =91.67 per cent, Sp =99.02 per cent, A=98.25 per cent, E=1.75. For phase 2, the IVS triggered four false alarms and some technical dysfunctions appeared (e.g. computer screen never turning off) that are easily overcome.

Results show the IVS’s efficacy at automatically detecting falls at home. Potential issues related to future installation in older adults’ homes were identified. This proof of concept led to recommendations about the installation and calibration of a camera-based fall detection system.

This paper highlights the potentialities of a camera-based fall detection system in real-world contexts and supports the use of the IVS to help older adults age in place.

Older adults are at a high risk of falling. The consequences of falls are worse when the person is unable to get up afterward. Thus, an intelligent video monitoring system (IVS) was developed to detect falls and send alerts to a respondent. This study aims to explore the implementation of the IVS at home.

A multiple case study was conducted with four dyads: older adults and informal caregivers. The IVS was implemented for two months at home. Perceptions of the IVS and technical variables were documented. Interviews were thematically analyzed, and technical data were descriptively analyzed.

The rate of false alarms was 0.35 per day. Participants had positive opinions of the IVS and mentioned its ease of use. They also made suggestions for improvement.

This study showed the feasibility of a two-month implementation of this IVS. Its development should be continued and tested with a larger experimental group.

The use of the Internet for Web‐based teaching and learning is fast becoming a reality. However, since it is difficult to verify the identity of the student through a simple user ID and password system on the client side, performance evaluation through test and examination through the Internet is still in its infancy. To overcome this main hurdle, a system has been designed and developed where a camera at the client computer is used to capture the student’s face and posture at random intervals during the test. The captured images are stored at the server and can be used to verify the identity of the person taking the test if the need arises. The system developed has been successfully used in a randomized multiple choice test in a course on analog and digital signals involving 450 students.

The paper aims to present key points regarding the development of an ultra‐small micro drill bit for packaging substrate hole processing.

Key points for the development of ultra‐small drill bits are presented. These are based on a study of the influential mechanisms of micro drill bit material properties, key parameters and coating techniques on the behaviours of micro drill bit. Experiments were conducted to verify the drilling capability of the developed ultra‐small micro drill bits.

The material properties of micro drill bits are of great importance in ensuring the performance. Helix angle, primary face angle and point angle are three key parameters that significantly influence drill bit behaviour. Computer‐aided engineering analysis, temperature monitoring and video monitoring techniques in high‐speed drilling are useful tools for achieving the optimal design of ultra‐small drill bits. Using coating technology on ultra‐small drill bits can improve their hit limits by nearly four times.

The paper highlights key points to consider when developing ultra‐small micro drill bits. The presented points can provide an overall understanding of the challenges and solutions during ultra‐small micro drill bit design. Additionally, this paper presents a solution for packaging substrate ultra‐small hole processing by mechanical drilling.

The efficiency of range telemetry, as currently practiced, is somewhat limited by the available display technology. The manpower, space and accuracy problems associated with current methods are examined, and the limitations of some new approaches are discussed The concept of Real Time Digital Strip Chart Emulation (RTDSCE), as exemplified by the ES2000 System, and the benefits inherent to such a technical approach are presented and discussed in detail These benefits include reduction of manpower and space requirements by the use of the workstation concept, the elimination of D/A conversion by direct recording of digitised signals, and the facilitation of critical realtime viewing through high resolution video monitoring.

Developing algorithms for automated detection and tracking of multiple objects is one challenge in the field of object tracking. Especially in a traffic video monitoring system, vehicle detection is an essential and challenging task. In the previous studies, many vehicle detection methods have been presented. These proposed approaches mostly used either motion information or characteristic information to detect vehicles. Although these methods are effective in detecting vehicles, their detection accuracy still needs to be improved. Moreover, the headlights and windshields, which are used as the vehicle features for detection in these methods, are easily obscured in some traffic conditions. The paper aims to discuss these issues.

First, each frame will be captured from a video sequence and then the background subtraction is performed by using the Mixture-of-Gaussians background model. Next, the Shi-Tomasi corner detection method is employed to extract the feature points from objects of interest in each foreground scene and the hierarchical clustering approach is then applied to cluster and form them into feature blocks. These feature blocks will be used to track the moving objects frame by frame.

Using the proposed method, it is possible to detect the vehicles in both day-time and night-time scenarios with a 95 percent accuracy rate and can cope with irrelevant movement (waving trees), which has to be deemed as background. In addition, the proposed method is able to deal with different vehicle shapes such as cars, vans, and motorcycles.

This paper presents a hierarchical clustering of features approach for multiple vehicles tracking in traffic environments to improve the capability of detection and tracking in case that the vehicle features are obscured in some traffic conditions.

Three‐dimensional printing (3DP) is an increasingly popular additive manufacturing (AM) process. The structure produced in 3DP comprises of two main elements: an external “shell” and an inner “core”. The variation of this structure and print strategy dictates many factors, such as the final physical properties, the final weight of the part, the total material usage, effects on warpage and the build speed. As such, the accuracy and repeatability of these geometric structures is of importance. The measurement and validation of the actual printed structure is especially challenging due to the nature of the materials system. The purpose of this paper is to present an effective method to analyze the internal structure of a 3DP.

A dedicated video‐monitoring system has been developed to capture and characterize the 3DP build structure layer‐by‐layer. A significant image‐processing phase involved image calibration, filtering, thresholding and segmentation. The investigation is composed by three substudies. First, the reliability of the developed system was determined by comparing nominal dimensions of a benchmark part with video and contact measurements. The two studies have focused on the “shell” and “core” characterization, respectively.

A resolution of 508 pixel per inch was determined. From the first studies, benchmark elements of 0.5 mm presented a deviation between 0.29 and 0.44 mm from their normal dimension. The thickness of the external shell was analyzed, in both clear and coloured modes. Dimensions ranged between 1.51 and 1.58 mm for a clear part, and 1.59 and 1.69 mm for the coloured version. A further study resulted in a 3D virtual model of the internal mesh structure, which had been printed at high saturation.

The internal structure of a 3D printed part has been successfully analyzed by in‐process monitoring providing information and data not available through conventional analysis of the final part. This system provides a solution for real‐time non‐destructive analysis, which is currently absent in various forms of AM.

Domestic violence is a threat to the well‐being of many families in the UK, and a great burden on health, social care and police resources. Its management requires swift action either to protect the victims in their own homes, or to move them to more appropriate accommodation where the perpetrators will be unable to find and harm them. However, the risk of violence often remains and requires some immediate action and access to support services on a 24‐hour basis. Special call lines have been created both at national and at local level, but these are not always suitable when there is a risk of the perpetrator being aware of such communications. Telecare offers a more sophisticated and responsive way of managing the risks, and is becoming popular with local authorities across the country. While basic systems using alarm pendants to raise an alert are popular with most authorities, the addition of smart sensors and the use of video monitoring can both be used to good effect. In the future, it may be assumed that a much wider range of telecare devices will be deployed to provide automatic detection of problems, and to ensure that victims of abuse are protected appropriately both in their homes and in other locations. Most local authorities use at least some elements of telecare, but there may be considerable potential for improving support by including a greater level of technology, some of which could be provided through Supporting People programmes or through the police.