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The linear analysis presented for the charge pump phase locked loops (CPPLLs) becomes inaccurate or incorrect where cycle slipping occurs. In this paper, an analytical approach is proposed, which explains the conditions in which cycle slipping happens. Using the analytical results, one can simply design or redesign a CPPLL to prevent or decrease cycle slipping and hence decreasing the locking time. The paper aims to discuss these issues.

To obtain cycle slipping conditions, CPPLL's signals in the time domain are tracked and cycle slipping condition is investigated. Based on the proposed analysis, by comparing a simple function of system's parameters with a threshold, cycle slipping is predicted.

The cycle slipping conditions are expressed in terms of system's parameters and the size of the input frequency step. The method is also generalized for a fast CPPLL with an aid-lock BBFC circuit. The good accuracy of the analytical predictions is verified using simulations in Matlab/Simulink.

A new analytical method for cycle slipping prediction in CPPLLs is presented. A closed form equation in terms of system's parameters and input frequency step has been presented, which can predict the cycle slipping possibility in the system without a need to perform the full time-consuming simulations. This analytical method that uses the LambertW function's properties proposes a threshold to predict cycle slipping in the system. This method not only can be used by designers to predict cycle slipping but can also be used to design the CPPLL in order to remove or decrease cycle slipping. The method is also generalized for fast locking charge pump PLLs and as a case study, cycle slipping prediction in the BBFC-CPPLL is performed.

Manual tool changes in flexible machining operations are now even faster following the introduction by Krupp Widia of a new rapid‐action locking system for its ‘Widaflex UTS’ radial toolholding system. A turn of 90 degrees is all that is needed to lock the tool head in position.

Reducing fatalities and increasing the number of students able to remain safe during an active shooter event is paramount to the health and well-being of schools and communities. Yet, methodological limitations and ethical concerns have restricted prior research on security measures during school shooter lockdown drills. This study aims to fill that gap by using virtual reality (VR) to statistically examine the effectiveness of active shooter response protocols in a simulated high school.

Using a full factorial, within-subjects experimental design, this exploratory investigation used VR technology to investigate whether automatic classroom door locks, centralized lockdown notifications and the presence of a school resource officer (SRO) significantly impacted student safety and casualty mitigation. Data were collected from a convenience sample of 37 individuals who volunteered to participate in 24 school shooter scenarios within a simulated virtual environment.

Multiple one-way analysis of variances indicated significant main effects for automatic classroom door locks and SRO presence. Automatic locks yielded faster lockdown response times, and both factors were significantly associated with higher numbers of secured classrooms.

Findings from the current study address the gap in existing literature regarding evidence-based school safety protocols and provide recommendations for using VR simulations to increase preparedness and reduce fatalities during an active school shooter event.

This paper aims to propose a new robust membrane finite element for the analysis of plane problems. The suggested element has triangular geometry. Four nodes and 11 degrees of freedom (DOF) are considered for the element. Each of the three vertex nodes has three DOF, two displacements and one drilling. The fourth node that is located inside the element has only two translational DOF.

The suggested formulation is based on the assumed strain method and satisfies both compatibility and equilibrium conditions within each element. This establishment results in higher insensitivity to the mesh distortion. Enforcement of the equilibrium condition to the assumed strain field leads to considerably high accuracy of the developed formulation.

To show the merits of the suggested plane element, its different properties, including insensitivity to mesh distortion, particularly under transverse shear forces, immunities to the various locking phenomena and convergence of the element are studied. The obtained results demonstrate the superiority of the suggested element compared with many of the available robust membrane elements.

According to the attained results, the proposed element performs better than the well-known displacement-based elements such as linear strain triangular element, Q4 and Q8 and even is comparable with robust modified membrane elements.

In the redesign process of assembly components that need adaptation to robotic assembly, designers can find support from structured methodologies for innovation, such as the theory of inventive problem solving (TRIZ). This paper aims to illustrate the authors’ methodology for redesigning gas hobs components for adaptation to robotic assembly.

A designer approaching a redesign task of an assembly component of any kind for adaptation to robotic assembly must consider, first of all, the features and limitations of existing robotic assembly systems; the generation of new design ideas that best fit the requirements may result to be a very challenging task. Here, the TRIZ methodology has proven useful for generating design ideas and finding the best solution.

The authors’ methodology approaches the challenges of redesign tasks for robotic assembly adaptation, which exploits knowledge of automatic and robotic assembly systems and the TRIZ method for innovation; it has proven useful in the redesign, checks and prototyping of gas hobs components.

This paper shows how the TRIZ methodology can be integrated into the redesign process and its impact on an industrial environment. The work’s main value is to provide a set of steps to help the designers change their design components approach that is necessary but not still implemented to optimize the use of the automation.

There's no shortage of advice, or promotional activity, among firms involved with industrial security; the police have their crime prevention units; and teh insurance companies can exercise their influence with risk‐prone clients. So why do theft losses continue their inexorable rise? Iain Mackenzie goes to Watford to look for the answer.

The purpose of this paper is to present a case, with live examples from a construction industry development initiative in India, for developing a proactive construction clients charter; and a core set of key performance indicators (KPIs), as basic tools for facilitating the expectations of this special issue in “securing clients’ organisational objectives and project aspirations throughout construction project lifecycles” apart from empowering construction industry improvements in general.

Having identified 19 critical issues in the Indian construction industry at two construction clients-academia roundtables, two of the “action teams” formed to address specific issue sets, separately developed a relevant construction clients charter and useful KPIs, respectively, through a combination of literature reviews and brainstorming conference calls, along with iterative drafts of, and feedback on interim outputs. Validation of “working papers” presented at a “Consolidation Roundtable” of construction clients and their consultants, elicited further suggestions for fine tuning of final outputs.

The charter was formulated in structured steps, including identifying “priorities” under four categories: overall, expectations from supply chains, by supply chains and by end users. The six sub-heads of the charter are on procurement, design, innovation and technology, project execution, human resource development and worker welfare, and quality, safety and sustainability. The “suggested KPIs” for building clients in India enable organisations to choose: from three different groups (i.e. design phase, construction phase, or business outcomes), and at three different levels (i.e. project/organisation level, benchmarking club level, or industry level).

There is no known overarching Construction Clients’ Charter at present. Some project KPI sets are available elsewhere. However, those developed in India, while focusing on project performance, also connect to organisational performance and business outcomes. Furthermore, KPIs are provided to separately probe client, consultant and contractor performance. Significantly, the charter and KPIs are outcomes from an industry-led self-improvement initiative launched with building construction clients at the forefront, rather than a top-down imposition from government. Furthermore, while prioritising client aspirations, they also address common supply chain and end-user concerns, which may also be interpreted as a longer-term win-win-win client’s aspiration.

The Electroplating Products and Equipment Business Area of Degussa AG, Frankfurt am Main, Federal Republic of Germany, has begun to supply a new selective electroplating plant. Under a co‐operation agreement with the Telmec company of Milan, Italy, this business area of Degussa, which is based in Schwäbisch Gmüd, Germany, has begun to market the Telmec SL 6 ‘Tab Plater’ throughout the world, with the exception of Italy and France. The equipment was developed specially for manufacturers of printed circuit boards, and is used for the continuous electroplating of strip contacts on these boards.