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Fabricated data jeopardize the reliability of large-scale population surveys and reduce the comparability of such efforts by destroying the linkage between data and measurement constructs. Such data result in the loss of comparability across participating countries and, in the case of cyclical surveys, between past and present surveys. This paper aims to describe how data fabrication can be understood in the context of the complex processes involved in the collection, handling, submission and analysis of large-scale assessment data. The actors involved in those processes, and their possible motivations for data fabrication, are also elaborated.

Computer-based assessments produce new types of information that enable us to detect the possibility of data fabrication, and therefore the need for further investigation and analysis. The paper presents three examples that illustrate how data fabrication was identified and documented in the Programme for the International Assessment of Adult Competencies (PIAAC) and the Programme for International Student Assessment (PISA) and discusses the resulting remediation efforts.

For two countries that participated in the first round of PIAAC, the data showed a subset of interviewers who handled many more cases than others. In Case 1, the average proficiency for respondents in those interviewers’ caseloads was much higher than expected and included many duplicate response patterns. In Case 2, anomalous response patterns were identified. Case 3 presents findings based on data analyses for one PISA country, where results for human-coded responses were shown to be highly inflated compared to past results.

This paper shows how new sources of data, such as timing information collected in computer-based assessments, can be combined with other traditional sources to detect fabrication.

To seek to produce low‐voltage, soft mechanical actuators entirely via freeform fabrication as part of a larger effort to freeform fabricate complete electromechanical devices with lifelike and/or biocompatible geometry and function.

The authors selected ionomeric polymer‐metal composite (IPMC) actuators from the literature and the authors' own preliminary experiments as most promising for freeform fabrication. The authors performed material formulation and manual device fabrication experiments to arrive at materials which are amenable to robotic deposition and developed an SFF process which allows the production of complete IPMC actuators and their fabrication substrate integrated within other freeform fabricated devices. The authors freeform fabricated simple IPMC's, explored some materials/performance interactions, and preliminarily characterized these devices in comparison to devices produced by non‐SFF methods.

Freeform fabricated IPMC actuators operate continuously in air for more than 4 h and 3,000 bidirectional actuation cycles. The output stress scaled to input power is one to two orders of magnitude inferior to that of non‐SFF devices. Much of this difference may be associated with process‐sensitive microstructure of materials. Future work will investigate this performance gap.

Device performance is sufficient to continue exploration of SFF of complete electromechanical devices, but will need improvement for broader application. The feasibility of the approach for producing devices with complex, non‐planar geometry has not been demonstrated.

This work demonstrates the feasibility of freeform fabricating IPMC devices, and lays groundwork for further development of the materials and methods.

This work constitutes the first demonstration of complete, functional, IPMC actuators produced entirely by freeform fabrication.

The purpose of this paper is to share valuable information about low‐cost microwave circuit research with academic and industrial communities that work, or want to work, in this field.

Screen‐printing technology has been chosen as the fabrication method because of simplicity and low costs. Different materials and printing parameters were tested in four generations of microstrip lines. After obtaining a satisfactory fabrication method, passive microwave components were printed, assembled, characterized and modeled.

Results demonstrated that the proposed low‐cost method allows fabricating low loss microstrip lines (15.63×10⁻³ dB/mm at 10 GHz), filters, inductors, and capacitors that work well up to 12 GHz.

Model accuracy of inductors and capacitors can be improved. The use of more precise calibration and de‐embedding techniques is necessary. More components can be fabricated and modeled to increase the flexibility and applicability of the proposed fabrication method.

The presented information can help limited budget companies and small educational institutions in electronics to fabricate microwave circuits at low costs. This is an excellent approach for students who want to learn how to make microwave frequency measurements and circuits without the need of expensive fabrication equipment and clean rooms.

The step‐by‐step fabrication method described in this paper allows fabricating different microwave components at low costs. The presentation of electrical models for each component completes the design‐fabrication cycle. As this information is gathered in a single source, it makes easier the incursion of new actors in the microwave field.

In wafer fabrication, the material cost of wafer is expensive. It is imperative to repair the defective wafers produced during the manufacturing process for reducing the cost and increasing the yield of wafer fabrication. However, repairing defective wafer will not only increase the work‐in‐process (WIP) level but the flow time of rework lots as well. In wafer fabrication, rework of wafer is only allowed in the photolithography area, where is the bottleneck of the entire wafer fab. The purpose of this paper is to develop a dispatching rule concerned with rework for photolithography area.

The research developed a load‐oriented integrated rule, Re‐Disp, to consider the lots' sequencing decision and rework consideration at the photolithography area, in wafer fabrication. Simulation test and statistical analysis have been done on a virtual wafer fabrication plant. In the simulation model, some combinations of dispatching and rework rules, which are popular in practice, have been modeled for benchmarking.

Integrated rules, Re‐Disp, is better than those combinations of dispatching rules and rework rules under statistical analysis. System will be more stable when the integrated dispatching rule is used for control of the wafer schedule.

The paper developed a new dispatching rule for wafer fabrication concerned with rework for photolithography.

Model Maker (MM) is a commercial rapid prototyping (RP) system using tiny jets to deposit thermoplastic materials onto a platform to build physical models and the associated support structures. Also, a cutter is employed to plane off the deposited surface in order to maintain smaller layer thickness and hence, model accuracy. The model’s accuracy is mainly affected by the profile layer thickness. The interior filling does not affect the model accuracy or layer thickness very much, but it significantly affects the building time. Hence, a new interior fast filling of MM using a spraying nozzle is proposed in this paper. The detail design, construction, and evaluation of the new proposed fast interior‐spraying process are presented. The results show that the building time using spaying nozzle is only 15 per cent of the time used by the original process.

This review paper aims to provide an overview of applications of direct rapid manufacturing assisted mold with conformal cooling channels (CCCs) and shows the potential of this technique in different manufacturing processes.

Key publications from the past two decades have been reviewed.

This study concludes that direct rapid manufacturing technique plays a dominant role in the manufacturing of mold with complicated CCC structure which helps to improve the quality of final part and productivity. The outcome based on literature review and case study strongly suggested that in the near future direct rapid manufacturing method might become standard procedure in various manufacturing processes for fabrication of complex CCCs in the mold.

Advanced techniques such as computer-aided design, computer-aided engineering simulation and direct rapid manufacturing made it possible to easily fabricate the effective CCC in the mold in various manufacturing processes.

This paper is beneficial to study the direct rapid manufacturing technique for development of the mold with CCC and its applications in different manufacturing processes.

The purpose of this paper is to obtain more design freedom and realize fast fabrication of mechanism which is the core subsystem of many machines and always consists of several parts with assigned relative motion.

The mechanism is digitally assembled and later directly fabricated by selective laser melting (SLM) without post‐assembly. The joint is re‐designed to facilitate powdered material removal; the displays and the corresponding support additions are discussed to avoid too many supports within the clearances. Then, a series of universal joint are directly fabricated using SLM machine and a minimum clearance of 0.1 mm is obtained; a crank rocker mechanism is also fabricated and it can achieve the required performances.

The digitally assembled mechanism can be successfully fabricated by SLM technique using metal powdered material.

It is well known that the components fabricated by SLM have good mechanical properties. Therefore, it can be expected that more mechanisms with more design freedom will be developed and be used in some practical fields with improvement of fabrication quality.

Conventional machining methods for fabricating piezoelectric components such as ultrasound transducer arrays are time-consuming and limited to relatively simple geometries. The purpose of this paper is to develop an additive manufacturing process based on the projection-based stereolithography process for the fabrication of functional piezoelectric devices including ultrasound transducers.

To overcome the challenges in fabricating viscous and low-photosensitive piezocomposite slurry, the authors developed a projection-based stereolithography process by integrating slurry tape-casting and a sliding motion design. Both green-part fabrication and post-processing processes were studied. A prototype system based on the new manufacturing process was developed for the fabrication of green-parts with complex shapes and small features. The challenges in the sintering process to achieve desired functionality were also discussed.

The presented additive manufacturing process can achieve relatively dense piezoelectric components (approximately 95 per cent). The related property testing results, including X-ray diffraction, scanning electron microscope, dielectric and ferroelectric properties as well as pulse-echo testing, show that the fabricated piezo-components have good potentials to be used in ultrasound transducers and other sensors/actuators.

A novel bottom-up projection system integrated with tape casting is presented to address the challenges in the piezo-composite fabrication, including small curing depth and viscous ceramic slurry recoating. Compared with other additive manufacturing processes, this method can achieve a thin recoating layer (as small as 10 μm) of piezo-composite slurry and can fabricate green parts using slurries with significantly higher solid loadings. After post processing, the fabricated piezoelectric components become dense and functional.

The purpose of this paper is to develop an inexpensive and environmentally friendly solid freeform fabrication technique, called the freeze‐form extrusion fabrication (FEF), and use this technique in advanced ceramic fabrication.

FEF uses a highly loaded aqueous ceramic paste (≥50 vol.% solids loading) with a small quantity (∼2 vol.%) of organic binder to fabricate a ceramic green part layer by layer with a computer‐controlled 3D gantry machine at a temperature below the freezing point of the paste. Further, a freeze‐drying technique is used for preventing deformation and the formation of cracks during the green part drying process. Following the freeze‐drying, the ceramic green part undergoes binder removal and is sintered to near full density.

Extrudable, alumina pastes of high solids loading and process parameters for FEF processing of these pastes have been developed. Paste rheological properties and stability, extrusion rate, 3D gantry motion speed and other process parameters strongly affect the quality of the final ceramic parts. The minimum deposition angle, which reflects the maximum amount of extrusion offset to produce components with overhanging features without using support materials, is strongly related to the fabrication (environment) temperature. The lower the fabrication temperature, the lower the minimum deposition angle that could be achieved. Four point bending flexure strengths of the FEF processed Al₂O₃ test samples were 219 and 198 MPa for longitudinally deposited and transversely deposited samples, respectively. Major defects, which limited the strength of the materials, were due to under‐filling during the extrusion.

Successful development of the FEF technique will introduce a new approach to manufacturing ceramic materials into useful, complex shapes and components. The significant advantages of this technique include the use of environmentally friendly processing medium (water), inexpensive method of medium removal (freeze‐drying), and a much smaller quantity of organic binder to remove by pyrolysis techniques. The products can be sintered to near full density.

As an application of the computer aided design and computer aided manufacturing (CAD/CAM) technology in prosthetics, computer aided socket design and computer aided socket manufacturing (CASD/CASM) is becoming an active field in the prosthetics research. In this paper, a CASD/CASM method for prosthetic socket fabrication is described in detail. This is different from other fabrication methods in its novel combination of the CAD/CAM technology with fused deposition modeling (FDM) technology. Prosthetic sockets for volunteer amputees have been designed and fabricated in a FDM machine. In order to test the fabrication result, a final product was used to perform a clinical trial and some results are reported. In addition, the deficiency of the long fabrication time is addressed and some feasible solutions are discussed.