Scan Design Research Articles

Linear and Volumetric Polyethylene Wear Patterns after Primary Cruciate-Retaining Total Knee Arthroplasty Failure: An Analysis Using Optical Scanning and Computer-Aided Design Models.

(1) Background: Analyses of retrieved inserts allow for a better understanding of TKA failure mechanisms and the detection of factors that cause increased wear. The purpose of this implant retrieval study was to identify whether insert volumetric wear significantly differs among groups of common causes of total knee arthroplasty failure, whether there is a characteristic wear distribution pattern for a common cause of failure, and whether nominal insert size and component size ratio (femur-to-insert) influence linear and volumetric wear rates. (2) Methods: We digitally reconstructed 59 retrieved single-model cruciate-retaining inserts and computed their articular load-bearing surface wear utilizing an optical scanner and computer-aided design models as references. After comprehensively reviewing all cases, each was categorized into one or more of the following groups: prosthetic joint infection, osteolysis, clinical loosening of the component, joint malalignment or component malposition, instability, and other isolated causes. The associations between volumetric wear and causes of failure were estimated using a multiple linear regression model adjusted for time in situ. Insert linear penetration wear maps from the respective groups of failure were further processed and merged to create a single average binary image, highlighting a potential wear distribution pattern. The differences in wear rates according to nominal insert size (small vs. medium vs. large) and component size ratio (≤1 vs. >1) were tested using the Kruskal-Wallis test and the Mann-Whitney test, respectively. (3) Results: Patients with identified osteolysis alone and those also with clinical loosening of the component had significantly higher volumetric wear when compared to those without both causes (p = 0.016 and p = 0.009, respectively). All other causes were not significantly associated with volumetric wear. The instability group differentiated from the others with a combined peripheral antero-posterior wear distribution. Linear and volumetric wear rates showed no significant differences when compared by nominal insert size (small vs. medium vs. large, p = 0.563 and p = 0.747, respectively) or by component (femoral-to-insert) size ratio (≤1 vs. >1, p = 0.885 and p = 0.055, respectively). (4) Conclusions: The study found increased volumetric wear in cases of osteolysis alone, with greater wear when combined with clinical loosening compared to other groups. The instability group demonstrated a characteristic peripheral anterior and posterior wear pattern. Insert size and component size ratio seem not to influence wear rates.

A Modified and Customized Wingsuit Flying Search (MCWFS)-based Approach for the Circular Scan Architecture

The circular scan architecture (CSA) is a widely used scan design technique in digital circuit testing that involves scanning test data through a circuit in a circular pattern. Several optimization approaches have been suggested so far to lessen the Test Data Volume (TDV), but no one has shown satisfactory results. Therefore, this paper proposes a Modified and Customized Wingsuit Flying Search algorithm to decrease the test data volume time. The proposed MCWFS-SBA-CSA introduces some novel features that distinguish it from traditional circular scan approaches. The concept of wingsuit flying is an innovative approach in the field of scan systems. This allows the scan that moves more dynamically and efficiently, enabling it to cover a larger area in a shorter time than traditional circular-scan approaches. After this phase, only scan-chosen inputs are required to obtain the next test pattern from the captured response. Therefore, required less Automatic test equipment (ATE) memory in this research so there is a Decreased cost in system-on-chip (SOC). The proposed method attains fast global searching capacity. The efficiency of the proposed technique attains 26.42%, 32.45%, and 29.34% higher compression ratio (CR), Test Application Time (TAT) reduction of SC-128 attains 29.45%, 34.67%, and 40.22% higher, TDV of SC-256 attains 32.23%, 36.34%, and 39.23% higher than existing methods, such as TDV for Circular Scan Approaches utilizing Modified Shuffled Shepard Optimization (TDV-CSA-MSSO), Effectual Very-large-scale integration Test data compression system for CSA under modified and colony metaheuristic (ETDC-CSA-MACMH), and Test Data Compression Utilizing Tetrad state Skip System (TDC-DC-TSSC) for Digital Circuits, respectively.

Establishing a CAD-CAM workflow for stabilization appliances (Michigan splints).

Stabilization appliances (Michigan splints) are considered well-studied and widely adopted for managing bruxism and temporomandibular disorders (TMDs). Traditionally, these appliances have been fabricated by wax modeling and pressing resin onto casts made from irreversible hydrocolloid or silicone impressions. This article provides a detailed description of an all-digital workflow that uses intraoral scanning and computer-aided design (CAD) software to design a stabilization splint on a digital cast that can be manufactured autonomously by a computer-aided manufacturing (CAM) grinding machine in a subtractive procedure. The workflow is applicable to both dentists and technicians. Special attention is given to aspects and procedures that are important for the successful fabrication of the splint. Working without a cast can save time and money, and the use of CAD-CAM technology provides a homogeneous splint material quality.

Design Optimisation of a Flat-Panel, Limited-Angle TOF-PET Scanner: A Simulation Study.

In time-of-flight positron emission tomography (TOF-PET), a coincidence time resolution (CTR) below 100 ps reduces the angular coverage requirements and, thus, the geometric constraints of the scanner design. Among other possibilities, this opens the possibility of using flat-panel PET detectors. Such a design would be more cost-accessible and compact and allow for a higher degree of modularity than a conventional ring scanner. However, achieving adequate CTR is a considerable challenge and requires improvements at every level of detection. Based on recent results in the ongoing development of optimised TOF-PET photodetectors and electronics, we expect that within a few years, a CTR of about 75 ps will be be achievable at the system level. In this work, flat-panel scanners with four panels and various design parameters were simulated, assessed and compared to a reference scanner based on the Siemens Biograph Vision using NEMA NU 2-2018 metrics. Point sources were also simulated, and a method for evaluating spatial resolution that is more appropriate for flat-panel geometry is presented. We also studied the effects of crystal readout strategies, comparing single-crystal and module readout levels. The results demonstrate that with a CTR below 100 ps, a flat-panel scanner can achieve image quality comparable to that of a reference clinical scanner, with considerable savings in scintillator material.

Penggunaan Prototype Media Pembelajaran Untuk Anak Usia Dini Menggunakan Teknik Scan Tiga Dimensi

This research creates a prototype of learning media for early childhood using 3D scanning techniques. The prototype is designed to introduce the variety of endemic fauna in Indonesia. The research method is Analysis, Design, Development, Implementation, and Evaluation (ADDIE). This learning media is designed with five stages: Analyzing the proximity between children and technology, designing animal icons and maps, designing a 3D scan prototype using Polycam Pro, testing the 3D Scan prototype, implementation of the 3D Scan prototype. Designing a 3D Scan using Polycam Pro is better using manual methods to produce images with clear textures. 3D Scan design using Polycam Pro produces 3D shapes of endemic animal objects that are published on the web as learning media for early childhood.

Considerations for practical use of tree-based scan statistics for signal detection using electronic healthcare data: a case study with insulin glargine

ABSTRACT Background Hypothesis-free signal detection (HFSD) methods such as tree-based scan statistics (TBSS) applied to longitudinal electronic healthcare data (EHD) are increasingly used in safety monitoring. However, challenges may arise in interpreting HFSD results alongside results from disproportionality analysis of spontaneous reporting. Research design and methods Using the anti-diabetes drug insulin glargine (Lantus®) we apply two different tree-based scan designs using TreeScan™ software on retrospective EHD and compare the results to one another as well as to results from a disproportionality analysis using SRD. Results The self-controlled tree temporal scan method produced the larger number of alerts relative to propensity-score matched approach; however, far fewer alerts were observed when analyses were limited to EHD in inpatient/emergency room settings only. Very few reference adverse events were observed using TBSS methods on EHD relative to disproportionality methods in SRD. Conclusion Differences in detected alerts between TBSS methods and between TBSS and disproportionality analysis of SRD are likely attributable to differences in data, comparator, and study design. Our results suggest that HFDS methods like TBSS applied to EHD may complement more traditional approaches such as disproportionality analysis of SRD to provide a more complete picture of product safety in the post-approval setting.

Design and Analysis of Jigs and Fixtures for Inspection Process

Abstract: In the realm of vehicle manufacturing, ensuring precise panel fitment is paramount for maintaining quality standards and customer satisfaction. This report delves into the significance of panel and fitment checking fixtures in the automotive industry. The study provides a thorough examination of the design, construction, and utilization of these fixtures, emphasizing their critical role in verifying the accuracy and alignment of vehicle panels during assembly. By employing advanced measurement techniques and precision engineering, these fixtures serve as indispensable tools for detecting deviations and inconsistenciesin panel fitment. Furthermore, the report explores the integration of innovative technologies such as 3D scanning and computer-aided design (CAD) in the development of these fixtures, enabling manufacturers to achieve higher levels of accuracy and efficiency in the quality control process. Through case studies and industry insights, the report showcases the practical application and effectiveness of panel and fitment checking fixtures across various stages of vehicle production. Additionally, it highlights the benefits of implementing standardized fixture designs and methodologies to streamline manufacturing processes and minimize production costs.

Effective engineering of a ketoreductase for the biocatalytic synthesis of an ipatasertib precursor

Semi-rational enzyme engineering is a powerful method to develop industrial biocatalysts. Profiting from advances in molecular biology and bioinformatics, semi-rational approaches can effectively accelerate enzyme engineering campaigns. Here, we present the optimization of a ketoreductase from Sporidiobolus salmonicolor for the chemo-enzymatic synthesis of ipatasertib, a potent protein kinase B inhibitor. Harnessing the power of mutational scanning and structure-guided rational design, we created a 10-amino acid substituted variant exhibiting a 64-fold higher apparent kcat and improved robustness under process conditions compared to the wild-type enzyme. In addition, the benefit of algorithm-aided enzyme engineering was studied to derive correlations in protein sequence-function data, and it was found that the applied Gaussian processes allowed us to reduce enzyme library size. The final scalable and high performing biocatalytic process yielded the alcohol intermediate with ≥ 98% conversion and a diastereomeric excess of 99.7% (R,R-trans) from 100 g L−1 ketone after 30 h. Modelling and kinetic studies shed light on the mechanistic factors governing the improved reaction outcome, with mutations T134V, A238K, M242W and Q245S exerting the most beneficial effect on reduction activity towards the target ketone.

Distal planar rotary scanner for endoscopic optical coherence tomography.

Optical coherence tomography (OCT) is becoming a more common endoscopic imaging modality for detecting and treating disease given its high resolution and image quality. To use OCT for 3-dimensional imaging of small lumen, embedding an optical scanner at the distal end of an endoscopic probe for circumferential scanning the probing light is a promising way to implement high-quality imaging unachievable with the conventional method of revolving an entire probe. To this end, the present work proposes a hollow and planar micro rotary actuator for its use as an endoscopic distal scanner. A miniaturized design of this ferrofluid-assisted electromagnetic actuator is prototyped to act as a full 360° optical scanner, which is integrated at the tip of a fiber-optic probe together with a gradient-index lens for use with OCT. The scanner is revealed to achieve a notably improved dynamic performance that shows a maximum speed of 6500rpm, representing 325% of the same reported with the preceding design, while staying below the thermal limit for safe in-vivo use. The scanner is demonstrated to perform real-time OCT using human fingers as live tissue samples for the imaging tests. The acquired images display no shadows from the electrical wires to the scanner, given its hollow architecture that allows the probing light to pass through the actuator body, as well as the quality high enough to differentiate the dermis from the epidermis while resolving individual sweat glands, proving the effectiveness of the prototyped scanner design for endoscopic OCT application.

Design of continuous zoom area array scanning infrared optical system with large area array

Design of continuous zoom area array scanning infrared optical system with large area array

Design of continuous zoom area array scanning infrared optical system with large area array

Design of continuous zoom area array scanning infrared optical system with large area array

Beam Scanning Design and Performance Analysis for Near-Field IRS-Aided Integrated Sensing and Communication Systems

Beam Scanning Design and Performance Analysis for Near-Field IRS-Aided Integrated Sensing and Communication Systems

Development of a Fast in Situ Scanning Tunneling Microscope for Studies of Electrocatalyst Surfaces

The atomic-scale understanding of processes at the interface between solid electrodes and liquid electrolytes is of high importance for electrochemical energy storage and conversion. Electrochemical scanning tunneling microscopy (ECSTM) is a key technique for the investigation of these interfaces and as such, it has seen widespread use. However, the image acquisition in a conventional ECSTM is a rather slow process, requiring tens of seconds or minutes per image. To help understand the precise reaction mechanisms of atomic and molecular species at solid-liquid interfaces, their movement and interactions need to be resolved. For this, much higher imaging rates are necessary. High-speed STMs (video STMs) are capable of operating at rates >10 images per second, which is sufficiently fast to observe and quantitatively study a wide range of surface dynamic processes, e.g., surface diffusion and growth [1]. However, this technique has not been widely employed, mainly because of the instrumental requirements.The development of an STM for fast in situ measurements poses a set of challenges, which require a carefully planned implementation. For operation in electrochemical environment, the potentials of both STM tip and sample need to be controlled and electrochemical currents at the tip need to be kept way below the tunneling current. Fast image acquisition requires a scanner with high mechanical stability to avoid the excitation of uncontrolled tip oscillations at its resonance frequencies. Additionally, high-bandwidth measurement and control electronics and a sophisticated control software with fast scan generation and data processing capabilities are essential. No commercial system that is capable of fulfilling these requirements exists up to now. For this reason, all existing video-rate STM studies have been performed with home-built setups that employ highly specialized hardware that is not easy to reproduce.In this contribution, we present a new ECSTM developed and built in our group. The setup is based on a Nanonis SPM controller by SPECS and a custom scanner, bipotentiostat, and coarse approach control that were integrated into this system. We show example data and images to demonstrate the performance of the STM. Furthermore, we reveal the modifications employed to make it capable of video-rate imaging. These include a novel scanner design with two independent piezo stacks for slow and high-speed movements and a custom high-bandwidth preamplifier integrated into the scan head as close as possible to the tip. Fast data acquisition is realized by an FPGA-based control software, which features a user-friendly frontend and a backend with good performance even at high image acquisition rates. This software is designed to run alongside the commercial control software for the slow STM operation so that switching between the slow and fast imaging modes is as frictionless as possible. We will show preliminary test results of the early implementation of the fast imaging mode.[1] O. M. Magnussen, Chem. Eur. J. 2019, 25, 12865.

A secure scan architecture using dynamic key to thwart scan-based side-channel attacks

Scan testing is widely used in the rigorous testing of modern integrated circuits. However, the controllable and observable nature of the scan design also provides opportunities for attackers who can utilise this structure to steal secret information stored in the chip. This paper proposes a secure Design for Testability (DFT) architecture to prevent scan-based attacks. The scheme uses a modified Linear Feedback Shift Register (LFSR) to dynamically generate keys for the scan design key generator and verifies them against a specific selection of test key flip-flops in the original scan chain, and locks the control signals by transmitting the outputs of the verification comparisons to a OR gate. When the test authorisation key is correct, the circuit performs a normal scan operation; otherwise, the circuit enters an abnormal test mode and the data in the scan chain is dynamically obfuscated, thus preventing from observing valid data or deriving an encryption key through the output of the scan chain.

Characterization of wind turbine flow through nacelle-mounted lidars: a review

This article provides a comprehensive review of the most recent advances in the planning, execution, and analysis of inflow and wake measurements from nacelle-mounted wind Doppler lidars. Lidars installed on top of wind turbines provide a holistic view of the inflow and wake characteristics required to characterize and optimize wind turbine performance, carry out model validation and calibration, and aid in real-time control. The need to balance the enhanced capabilities and limitations of lidars compared to traditional anemometers inspired a broad variety of approaches for scan design and wind reconstruction, which we discuss in this review. We give particular emphasis to identifying common guidelines and gaps in the available literature with the aim of providing an exhaustive picture of the state-of-the-art techniques for reconstructing wind plant flow using nacelle-mounted lidars.

Self-Test Library Generation for In-Field Test of Path Delay Faults

New semiconductor technologies for advanced applications are more prone to defects and imperfections related, among several different causes, to the manufacturing process, aging and cross-talks. These phenomena negatively affect the circuit’s timing and can be effectively modeled by means of the path delay fault (PDF) model. While path delay testing is currently supported by commercial Automatic Test Pattern Generation tools for scan designs, functional testing covering PDFs is not widely adopted, mainly because of the high cost for test generation. On the other side, functional test is already widely adopted for in-field test of stuck-at faults, which is often performed resorting to the execution of suitable test programs (Self Test Libraries, or STLs). This approach is attractive, since it can be performed at-speed with limited time constraints and high flexibility, making it a suitable in-field test solutions. Previous work assessed the feasibility and validity of functional approaches based on test programs targeting PDFs. In this work, we present the first systematic method for the development of very high fault coverage test programs for PDFs, which largely outperform test programs written for other fault models. Moreover, the proposed method allows the identification of functionally untestable faults. The effectiveness of the proposed approach was proven on an open-source RISC-V processor core, where 100% coverage of the functionally testable longest paths was achieved, compared with an initial coverage of 0.52% achieved with test programs targeting stuck-at faults. Results demonstrate that shorter paths are also effectively covered.

Efficient design of a wideband tunable microstrip filtenna for spectrum sensing in cognitive radio systems

This paper presents a novel design of a compact, wideband tunable microstrip filtenna system for effective spectrum sensing in cognitive radio (CR) applications. The proposed filtenna structure has a total bandwidth of 1.63,text{GHz} and flexible frequency scanning design throughout the frequency range from 1.93,text{ to },3.56,text{ GHz} with high selectivity and narrow bandwidths ranging from 39.9,text{to}53,text{MHz}. Frequency tuning is accomplished electrically via integrating a varactor diode into the filtenna construction. The filtenna is realized on a Rogers TMM4 substrate with h=1.52,text{mm} thickness and relative dielectric constant of {varepsilon }_{r}=4.5 with dimensions of (25times 35), {text{mm}}^{2}. The obtained gain and efficiency of the filtenna ranged from 0.7 to 2.26,text{dBi} and 49% to 60%, respectively, within the tuning range. Simple biasing circuitry, wideband operation, and compact planar structure are distinctive and appealing aspects of the design. For the manufactured prototypes, a significant level of agreement is found between the simulated and measured results in terms of scattering parameter {text{S}}_{11} and radiation patterns at different operating frequencies.

Determining the Levels of Writing Travel Articles of Secondary School 7th Grade Students

In this study, it was aimed to develop a rubric to determine the travel writing levels of secondary school 7th grade students and to determine the students› travel writing skill levels. The descriptive scanning design of the quantitative model was adopted. It was decided to develop an analytical rubric because it serves to measure the sub-skills of each skill and can be presented as feedback to the students. The rubric consists of three dimensions: layout, spelling, and punctuation, language and expression, and 18 items. It consists of 4 levels 1 (improved), 2 (moderate), 3 (good), and 4 (very good). The study group of the research consists of 114 7th grade students. The students in the study group were asked to write a travel writing text in one class hour and the travel writings were evaluated by two experts using the travel writing rubric. The collected data were analyzed using the descriptive analysis technique. As a result of the research, it was determined that most of the students were at a good level in using titles, including observations and impressions, commenting on the places visited, giving place to their memories about the trip, and making descriptions and coherent writing in their travel writings. In addition, it was determined that the students did not compare the places they visited and the places they lived in their travel writings in terms of place and society, did not give information about the geographical and historical characteristics of the place visited, and did not talk about the traditions and customs of the place visited.

Review of low-cost light sources and miniaturized designs in photoacoustic microscopy.

Photoacoustic microscopy (PAM) is a promising imaging technique to provide structural, functional, and molecular information for preclinical and clinical studies. However, expensive and bulky lasers and motorized stages have limited the broad applications of conventional PAM systems. A recent trend is to use low-cost light sources and miniaturized designs to develop a compact PAM system and expand its applications from benchtop to bedside. We provide (1)an overview of PAM systems and their limitations, (2)a comprehensive review of PAM systems with low-cost light sources and their applications, (3)a comprehensive review of PAM systems with miniaturized and handheld scanning designs, and (4)perspective applications and a summary of the cost-effective and miniaturized PAM systems. Papers published before July 2023 in the area of using low-cost light sources and miniaturized designs in PAM were reviewed. They were categorized into two main parts: (1)low-cost light sources and (2)miniaturized or handheld designs. The first part was classified into two subtypes: pulsed laser diode and continuous-wave laser diode. The second part was also classified into two subtypes: galvanometer scanner and micro-electro-mechanical system scanner. Significant progress has been made in the development of PAM systems based on low-cost and compact light sources as well as miniaturized and handheld designs. The review highlights the potential of these advancements to revolutionize PAM technology, making it more accessible and practical for various applications in preclinical studies, clinical practice, and long-term monitoring.

ASIC Implementation for Multiple Scan at Register Transfer Level

Design for testability (DFT) is introduced to reduce the complexity of testing integrated circuit and help improve fault coverage. However, conventional DFT with additional 2-to-1 multiplexer (MUX) might add an increasing amount of delay and area overhead. Therefore, register transfer level (RTL) scan design is introduced to overcome this problem. This paper aims to present the development of an ASIC with RTL scan design by using multiple scan paths instead of the conventional technique, which is gate-level (GL) scan insertion to insert scan cells. This method inserts multiple scan cells by utilizing the existing multiplexer and operational units in order to reduce area overhead and delay. Besides, multiple scan paths are implemented instead of a single scan chain to reduce the complexity of the testing process, where a single scan chain has long test application times due to the high number of clock cycles for the scan chain process. RTL design is also modified by adding an extra gate for multiple scan chain insertion. The graph is derived in order to analyse the connection between registers such that the multiple scan paths can be determined accordingly. Synopsys tool is used for synthesized, placement and routing and performing automatic test pattern generation while static timing analysis is used to verify the results of the setup slack time for ASIC design. The simulation result shows that multiple scan paths insertion at RTL level has an area overhead and slack time of about 3.79% and 0.44ns less compared to multiple scan paths insertion at GL for a finite impulse response circuit with comparable high fault coverage and small delay. A comparison of the performance metrics such as area, setup slack time, and fault coverage of the multiple scan chain is done between the RTL scan and GL scan.