Component Matching Research Articles

Rapid characterization of polysaccharides from marine animals using chemical degradation combined with liquid chromatography mass spectrometry.

Glycosaminoglycans of marine origin have exceptional biological activities, but rapid elucidation strategies for precise structures are still lacking. In this study, the optimal conditions for deacetylation of glycosaminoglycans were optimized first. The hydrazinolysis time of 24 h was determined as the final condition, oligosaccharides with a degree of polymerization of 2-14 are mainly produced after hydrazinolysis. Then mixed oligosaccharides generated by deacetylation-deamination cleavage of polysaccharides were detected with hydrophilic interaction chromatography with tandem mass spectrometry (HILIC-MS/MS), and the total ion chromatography showed excellent resolution. The mass spectrometry data were automatically processed by GlycReSoft, and the corresponding matching results were obtained according to the set parameters. A small amount of keratan sulfate exists in oligosaccharides of Teuthida and Salmo salar, and ion peaks corresponding to IdoA-GalNAc4S exist in oligosaccharides of Scophthalmus maximus and Salmo salar. The results of the manual analysis of the mass spectrometry data verified that the HILIC-MS/MS combined with automatic analysis by software adopted in this study could achieve accurate matching and matching of mixed oligosaccharide components. The establishment of a rapid and accurate analysis strategy for the structure of glycosaminoglycans in this study will help the development of its application and standardized industrial production.

Modal Matching of Key Components in the Launching System Based on Response Surface Method

This chapter adopts Response Surface Methodology (RSM) combined with dynamic simulation and statistical analysis to deeply investigate the impact of modal matching of the inherent frequencies of key components of the launching system on the disturbances at the launch box opening during firing. Through experimental design, a polynomial fitting response surface model is established between design parameters and response objectives. The ultimate goal is to find the optimal design scheme that minimizes the initial disturbance, thereby achieving effective modal matching between the main components of the launching device. This research aims to provide a theoretical basis for improving firing accuracy and system stability.

Stability and Matching Techniques on Microwave Amplifier using Inhomogeneous Dielectric Resonator: Preliminary Study

Stability and matching techniques on microwave amplifier have been an important consideration to maintain the required performances, such as high power for the high-power amplifier and low noise for low noise amplifier. Simultaneously, the issues of the stability need more attention to avoid the presence of the oscillations. Typically, the stability factor and matching components of the microwave amplifier are frequency dependent. Thus, a frequency tunable mechanism is required to ascertain that frequency of the microwave amplifier resides within the stable region. The dielectric resonator is incorporated as the frequency tunable mechanism that implemented to overcome this issue. The characteristics of the dielectric resonator are evaluated on their physical parameter and material with different topologies of the parallel microstrip lines. This includes the spacing and curves configuration and the orientation of angular position for the dielectric resonator, especially for the multi-permittivity dielectric resonator. Regarding the preliminary study, the angular position of the multi-permittivity dielectric resonator does not influence the stability performances of microwaves amplifier, especially on the resonant frequency. The obtained best configuration of proposed dielectric resonator is consisting of 155-degree curves configuration with 19 mm spacing between the parallel microstrip lines for same waveguide port position. This configuration of the proposed dielectric resonator is incorporated as stability element and matching components that known as dielectric matching for conditional stable and unconditional stable transistors at 5 GHz.

Workers, Workplaces, Sorting, and Wage Dispersion in Mexico

Between 2004 and 2018, the spread of wages in Mexico’s private labor sector remained stable. Nonetheless, the underlying factors behind salary dispersion underwent significant shifts nationally and regionally. We analyze a matched employer-employee dataset comprising the near-universe of Mexico’s formal workforce. We estimate log wage models with worker and workplace fixed effects capturing over 94% of wage variation. We then decompose national and regional earnings dispersions into worker, workplace and assortative matching components. At the national level, we find that sorting increased its importance over time, from explaining 16% of total wage variance to 19% by the end of the period. Worker- and workplace-specific factors contributed between 37% to 44% and 33% to 37% to the total spread of remunerations, respectively. Workplace factors became increasingly important during the 2014–2018 time segment, to the point that their contribution to total wage variance is equivalent to that of worker factors. The influence of workplace factors on wage dispersion correlates negatively with regional economic development: It is lowest in the North, Mexico’s most-developed region, and largest in the South, the country’s least-prosperous region. JEL Classification Codes: J21; J31; R23; O15; O54

Optimization design of assembly sequence for the proton exchange membrane fuel cell stacks with dimensional errors

Proton exchange membrane fuel cell (PEMFC) stacks are assembled by numerous bipolar plates (BPPs) and membrane electrode assemblies (MEAs). Component manufacturing errors are inevitably caused during the production process and brought into the stack, affecting the mechanical consistency of every cell. Aiming to improve the uniformity of the assembled stack effectively, this paper establishes a novel assembly deviation model based on the asymptotic homogenization (AH) method and proposes an assembly sequence optimization approach for the stack with dimensional errors using the genetic algorithm. The results reveal that dimensional errors significantly affect the equivalent mechanical properties of the stack. Reasonable matching of components with different types of dimensional errors is an effective method to avoid the cumulative negative impacts on the mechanical behavior of the stack. Statistically, the optimization of the assembly sequence can improve contact pressure uniformity in a 10-cell stack by more than 9.00%, while reducing the maximum contact pressure by 15.55%. This methodology is also applicable to improving the assembly uniformity of other stacked structures.

Emulation and detection of physical faults and cyber-attacks on building energy systems through real-time hardware-in-the-loop experiments

The increasing use of remote or mobile access, integrated wearable technologies, data exchange, and cloud-based data analytics in modern smart buildings is steering the building industry towards open communication technologies. The increased connectivity and accessibility could lead to more cyber-attacks in smart buildings. On the other hand, physical faults (e.g., HVAC − heating, ventilation, and air-conditioning faults) may have similar adverse impacts as those from the cyber-attacks on building energy systems, such as occupant discomfort, energy wastage, and equipment downtime. However, current physical behavior-based anomaly detection methods fail to differentiate between cyber-attacks and physical faults in building energy systems. Moreover, the challenge in collecting real-world threat data with ground truth has led researchers to rely on numerical models with user-defined assumptions, which may not accurately reflect real-world conditions due to the lack of in-situ experimental datasets. To address these challenges and gaps, this paper presents a flexible hardware-in-the-loop (HIL) testbed for generating cyber-attack and physical fault datasets and demonstrating threat detection algorithms in a real building automation system (BAS) environment. This testbed combines hardware (i.e., real BAS with local HVAC controllers and a physical network) with software (i.e., high-fidelity models to represent behaviors of building envelope and HVAC energy systems), enabling emulations of realistic threats. Five HIL experiments, including one baseline without any threats, two with physical faults, and two with cyber-attacks, were conducted to generate datasets containing detailed network traffic and system states. A joint classification framework, incorporating a network analyzer and a physical HVAC fault detector, was proposed to automatically detect cyber-physical abnormalities on BAS at both the network and the physical HVAC levels. The network analyzer comprises a conditional random fields (CRF) based command validator and a statistics-based detection strategy. The fault detector employs a weather and schedule-based pattern matching and feature-based principal component analysis (WPM-FPCA) method. Evaluation of the classification using four metrics from the multi-class confusion matrix revealed an average accuracy of 90.2 %, recall of 89.7 %, precision of 88.5 % and F1-score of 89.2 %. These results demonstrate that the proposed joint classification framework can effectively differentiate between specific types of cyber-attacks (e.g., device reinitialization attack, network Denial-of-Service attack) and physical faults (e.g., air handling unit operational fault, cooling coil valve stuck) in real time for improved building energy management.

Design of a highly efficient reconfigurable C/X dual‐band 15W GaN MMIC power amplifier using amplifier‐switch fusion technique

AbstractThis letter introduces the design of a highly efficient reconfigurable C/X dual‐band power amplifier (PA). Conventional dual‐band designs connect two amplifier branches for each band by a switch, whose transmitting losses will limit the efficiency of the PA. In alternative to the switching solution, the authors propose a novel design method using two branches of output matching networks (OMN) which the 5–6 and 8–12 GHz branch acting as active loads for each other, respectively. The band‐pass OMNs are applied, and parts of the passive matching components are replaced by transistors for channel selection. The proposed design has been simulated, implemented, and measured. The experimental results demonstrate a power added efficiency (PAE) of 45% at a pulsed output power (Pout) of 42 dBm in 5–6 GHz while a PAE greater than 39% at 42 dBm Pout in 8–12 GHz. Moreover, the second and third harmonics of both operating bands are compressed to −35 and −40 dBc, respectively. The proposed design technique addresses the challenges of low‐efficiency and lower‐band harmonic suppression in traditional dual‐band designs, making it suitable for application in next‐generation satellite communication and remote sensing systems.

Minimal Realization Plus Current Output CC-based Biquad Circuit

This paper presents a minimal design of a biquad circuit using only one plus current output type-II current conveyor (CCII), one differential voltage current conveyor (DVCC) and grounded passive components. The circuit enables the implementation of all 5 basic filter types: low-pass (LP), band-pass (BP), high-pass (HP), band-stop (BS) and all-pass (AP) by the selecting and adding of the input and output currents with no component matching constraints. Moreover, the circuit parameters ω0 and Q can be set simply by adjusting the circuit components. The proposed biquad circuit performance has very low sensitivity to circuit components due to its simple structure and a small number of devices (2 active and 4 grounded passive components). This allows the circuit to work at high frequencies. The performance of the proposed topology was evaluated through PSPICE simulator using the 0.18 mm CMOS technology from the Taiwan Semiconductor Manufacturing Company (TSMC).

MODL-06. USING HYDROGEL MODELS TO RECAPITULATE THE TUMOUR-IMMUNE MICROENVIRONMENT OF AGGRESSIVE GROUP 4 MEDULLOBLASTOMA TUMOURS

Abstract BACKGROUND Medulloblastoma is the most common malignant childhood brain-tumour, predominantly affecting children between the ages of one and nine. It is divided into four molecular subgroups amongst which, Group 3 (G3) and Group 4 (G4) subgroups have the worst prognosis. Subgroups possess distinct extracellular-matrix (ECM) and tumour immune microenvironments (TIME) directly influencing therapy-response and metastasis. Current models of medulloblastoma fail to precisely recreate the complex, subgroup-specific TIME and do not mimic intricate immune-tumour heterotypic signalling facilitating immune-evasion. Here we use a HyStem-hydrogel which forms a hyaluronan-rich environment mimicking the natural brain architecture. This overcomes several limitations of current MB models, allowing customisation of subgroup matching of ECM components, adjustable ECM-stiffness and co-culturing of immune cells. METHODS HyStem-hydrogels were co-assembled with ECM components (with/without laminin) and G4 medulloblastoma cell line CHLA-01-MED. Hydrogels were imaged every three-days using an EVOS M7000 system and assessed for cell-viability with PrestoBlue every seven days. Co-culture laminin-supplemented HyStem hydrogels were established with M1-like or M2-like resting/activated macrophages and their growth tracked in the same manner. On day twenty-eight, hydrogels were fixed and stained for markers of cellular proliferation (Ki-67), ECM (laminin, vitronectin) and macrophage markers. Media from hydrogel co-cultures was collected and ELISAs permofmed to assess cytokine production. RESULTS Hydrogels with/without laminin both remained viable and stable for 28 days. Laminin-supplemented hydrogels displayed a mixed laminar-nodular phenotype which mirrored the heterogenous nature of G4 patient-tumours. Co-culture of CHLA-01-MED cells with activated-macrophages led to cytokine production and altered growth patterns. CONCLUSION We show that HyStem hydrogels recapitulate biologically relevant behaviour of aggressive G4-MB tumours in vitro and represent a promising model for G4-tumours. Future research will involve inclusion of additional brain relevant cells/ECM components and comparisons to a fully customisable peptide-amphiphile hydrogel.

Unique Operating Conditions Analysis of Turboshaft Engines Based on Nonlinear Integrated Model

The unique mission of the helicopter compared to the fixed-wing aircraft introduces challenges to the aerodynamic stability of the turboshaft engine. Thus, the assessment of the availability of stability margin for special operating conditions in the envelope of this equipment is required to guarantee flight safety. In this paper, a rapid nonlinear complete engine method is developed to investigate the effect of helicopter ground-effect operation and high-altitude hovering on aerodynamic stability by considering factors including inlet distortion and component matching. Research indicated that the most dangerous point of stability margin in a unique section of the flight envelope is high altitude hovering, with about a 16.7% reduction in available stability margin compared to standard ground test conditions. This paper also investigates the effects of typical helicopter ground effects on a turboshaft engine and shows that the stability margin will be reduced by a maximum of 1.43% in hovering if the influence of ground effects in the flight envelope is not considered in the design.

Impact of sharing imprecise information on fixed-bin selective assembly

Fixed-Bin Selective Assembly (FBSA) is widely used to improve the assembly quality of single units of different component types. FBSA has parts with similar dimensions, but with slight deviations due to production variances, sorted into pre-determined bins. A selection is made from paired bins for assembly. To ensure enough components, assemblers adopt a proactive or reactive strategy. For the proactive, predictions of component usage quantities are used to adjust processes for the internally manufactured matched component prior to production. With the reactive, component inventory levels are adjusted after assembly. The performance of each can be improved with information about incoming part dimensions. However, the communicated information may be imprecise. We developed a Bayesian Measurement Error Model to evaluate the impact of imprecision, in the supplier’s communicated information, on the efficacy of FBSA with either strategy. The model was tested with parameters obtained from a US assembler of combustion engines. We find that in most scenarios, the proactive approach results in better FBSA efficacy on average. A key exception was when imprecise information about the mean was communicated, resulting in no significant difference. The reactive approach is typically easier to implement, therefore it may be preferred when communicated information about the mean of incoming part dimensions is often inaccurate.

Tracing Tumor Heterogeneity of Pleomorphic Carcinoma of the Lung

IntroductionPulmonary pleomorphic carcinoma (PPC) is an aggressive and highly heterogeneous NSCLC whose underlying biology is still poorly understood. MethodsA total of 42 tumor areas from 20 patients with PPC were microdissected, including 39 primary tumors and three metastases, and the histologically distinct components were subjected to whole exome sequencing separately. We further performed in silico analysis of microdissected bulk RNA sequencing and methylation data of 28 samples from 14 patients with PPC. We validated our findings using immunohistochemistry. ResultsThe epithelial and the sarcomatoid components of PPCs shared a large number of genomic alterations. Most mutations in cancer driver genes were clonal and truncal between the two components of PPCs suggesting a common ancestor. The high number of alterations in the RTK-RAS pathway suggests that it plays an important role in the evolution of PPC. The metastases morphologically and genetically resembled the epithelial or the sarcomatoid components of the tumor.The transcriptomic and epigenetic profiles of the sarcomatoid components of PPCs with matched squamous-like or adenocarcinoma-like components differed from each other, and they shared more similarities to their matched epithelial components. NCAM1/CD56 was preferentially expressed in the sarcomatoid component of squamous-like PPCs, whereas CDH1/E-Cadherin expression was down-regulated in the sarcomatoid component of most PPCs. ConclusionLung adenocarcinoma-like PPCs are mainly driven by RTK-RAS signaling, whereas epithelial-mesenchymal transition programs as highlighted by increased NCAM1 and decreased CDH1 expression govern the epithelial-sarcomatoid transition between the clonally related tumor components. Several alterations in PPCs pinpoint therapeutic opportunities.

A Survey of Source Code Search: A 3-Dimensional Perspective

(Source) code search is widely concerned by software engineering researchers because it can improve the productivity and quality of software development. Given a functionality requirement usually described in a natural language sentence, a code search system can retrieve code snippets that satisfy the requirement from a large-scale code corpus, e.g., GitHub. To realize effective and efficient code search, many techniques have been proposed successively. These techniques improve code search performance mainly by optimizing three core components, including query understanding component, code understanding component, and query-code matching component. In this paper, we provide a 3-dimensional perspective survey for code search. Specifically, we categorize existing code search studies into query-end optimization techniques, code-end optimization techniques, and match-end optimization techniques according to the specific components they optimize. These optimization techniques are proposed to enhance the performance of specific components, and thus the overall performance of code search. Considering that each end can be optimized independently and contributes to the code search performance, we treat each end as a dimension. Therefore, this survey is 3-dimensional in nature, and it provides a comprehensive summary of each dimension in detail. To understand the research trends of the three dimensions in existing code search studies, we systematically review 68 relevant literatures. Different from existing code search surveys that only focus on the query end or code end or introduce various aspects shallowly (including codebase, evaluation metrics, modeling technique, etc.), our survey provides a more nuanced analysis and review of the evolution and development of the underlying techniques used in the three ends. Based on a systematic review and summary of existing work, we outline several open challenges and opportunities at the three ends that remain to be addressed in future work.

Microtexture region segmentation of eddy current testing data using a structural prior

Microtexture regions (MTRs) are collections of grains with similar crystallographic orientation. Because their presence in titanium alloys can significantly impact aerospace component life, a nondestructive method to detect and characterize MTR is needed. In this work, we propose to use data from two nondestructive evaluation methods, eddy current testing (ECT) and scanning acoustic microscopy (SAM), in order to recover the boundary and dominant crystallographic orientation of each MTR in a specimen. ECT is an electromagnetic method that is sensitive to changes in crystallographic orientation associated with MTR; however, its low resolution prevents it from resolving MTR boundaries well. In contrast, SAM is a high frequency ultrasound method that is able to resolve MTR boundaries but is not sensitive to orientation. This paper proposes an algorithm to characterize MTR that makes use of a method known as covariance generalized matching component analysis. This method is used to build a surrogate linear forward model that relates MTR boundaries and orientation to ECT data. The model is inverted using the SAM data as a structural prior. We demonstrate this technique using simulated ECT and experimental SAM data from a large grain titanium specimen.

Delegated Private Matching For Compute

Private matching for compute (PMC) establishes a match between two datasets owned by mutually distrusted parties (C and P) and allows the parties to input more data for the matched records for arbitrary downstream secure computation without rerunning the private matching component. The state-of-the-art PMC protocols only support two parties and assume that both parties can participate in computationally intensive secure computation. We observe that such operational overhead limits the adoption of these protocols to solely powerful entities as small data owners or devices with minimal computing power will not be able to participate. We introduce two protocols to delegate PMC from party P to untrusted cloud servers, called delegates, allowing multiple smaller P parties to provide inputs containing identifiers and associated values. Our Delegated Private Matching for Compute protocols, called DPMC and DsPMC, establish a join between the datasets of party C and multiple delegators P based on multiple identifiers and compute secret shares of associated values for the identifiers that the parties have in common. We introduce a rerandomizable encrypted oblivious pseudorandom function (OPRF) primitive, called EO, which allows two parties to encrypt, mask, and shuffle their data. Note that EO may be of independent interest. Our DsPMC protocol limits the leakages of DPMC by combining our EO scheme and secure three-party shuffling. Finally, our implementation demonstrates the efficiency of our constructions by outperforming related works by approximately 10x for the total protocol execution and by at least 20x for the computation on the delegators.

Development of a scanning acoustic microscopy-based structural prior for microtexture region characterization

Nondestructive evaluation (NDE) plays a crucial role in ensuring aircraft availability. The current NDE paradigm often relies on mono-modal testing and signal-over-threshold criteria to provide robust defect or damage detection, not characterization. One example is found in the risk-based management of surface-breaking cracks in metal, where cracks of a given size can be detected by eddy current testing (ECT) with a calculable probability. Yet, there are cases where detection proves insufficient. Consider the case of microtexture regions (MTR) found in certain titanium alloys, which can increase the risk of cold dwell fatigue failure when found above a certain size and in specific orientations relative to the surrounding material. At present, the size and orientation of MTR cannot be characterized using only one NDE modality. In this work, a data fusion-based solution to MTR characterization is developed. First, two inspection methods—scanning acoustic microscopy (SAM) and ECT—are selected, where each method is individually capable of only partial characterization. Then, matching component analysis is used to develop a surrogate forward model relating MTR orientation to ECT output. This data is then inverted using boundaries provided from the SAM data as a structural prior.

An Evaluation of Anatomic Referencing for Femoral Component Sizing Using Computed Tomography-Based Computer Modeling.

One of the critical steps in total knee arthroplasty is femoral component positioning and sizing. Historically, there was wider variability between femoral component sizes, necessitating the concepts of anterior referencing (AR) and posterior referencing (PR). With the introduction of smaller increments between sizes, the concept of anatomic referencing has been introduced to replace AR and PR. The intent of this study was to validate the concept of anatomic referencing and show that with 2 mm increments in femoral sizes, the femoral component can be placed flush to the anterior cortex while maintaining posterior condylar offset (PCO). Digital surface models were created using 515 femurs from an established computed tomography database. Virtual bone resections, component sizing and placement were performed assuming neutral mechanical axis and a cartilage thickness of 2 mm. The appropriately sized femoral component, which had 2 mm incremental sizes, was placed flush with the anterior cortex with restoration of the PCO. The anterior-posterior distance from the posterior surface of the component to the medial and lateral surfaces of the posterior condylar cartilage were measured. The medial condyle was the limiting condyle in the majority of cases (73%). The average medial gap after appropriate femoral component matching was 0.6 mm (0.39-1.41 mm) across all sizes. The overall average condylar gap was 1.02 mm. The most common femoral component was a size 7 (57.2 mm) and the average femoral AP width was 55.9 mm. Anatomic referencing with an implant system that has 2-mm increments in femoral component sizing provides an alternative to AR and PR without compromise. Anatomic referencing allows for perfect alignment of the anterior flange of the femoral component to the anterior cortex of the femur while restoring the native PCO to within 1 mm. This avoids having to choose between AR or PR when in between femoral sizes.

A novel method for segmentation of titanium microtexture regions via sensor data fusion

The current nondestructive inspection paradigm of mono-modal testing and signal-over-threshold call criteria is insufficient for characterization of microtexture regions in titanium alloys, which exceeds the capabilities of any single, practical sensing technique that could be deployed to a manufacturing environment for quality control. In this work, we develop a data fusion-based solution to microtexture region characterization. The material problem and potential inspection methods are reviewed, and registered datasets are presented. Next, we develop a data fusion algorithm that combines covariance-generalized matching component analysis and a conditionally Gaussian hypermodel to successfully estimate the boundaries and average crystallographic orientations of microtexture regions from scanning electron microscopy electron backscatter diffraction and eddy current testing data.

Parametric analysis of thermal cycle of a short take-off and vertical landing engine

Abstract Short take-off/vertical landing (STOVL) engine is an emerging power source for fighter planes that can perform takeoff and landing operations in tight quarters. As the aforementioned function requires specific component design and matching, it is vitally necessary to study the impacts of various component states on engine performance and stability. This paper develops a performance model for STOVL engines based on nonlinear component models and validates the modelʼs correctness. Variable component working conditions and settings are altered, engine performance is forecasted and observed, and the mechanism underlying this trend is investigated. The results indicate that the performance of the STOVL engine is greatly influenced by the design parameters of the gas path, such as the bypass ratio and the injection volume of the roll nozzle, and is highly dependent on the correct adjustment of the rear bypass injector and the throat area of the nozzle.

Parametric Study and Optimization of Hydrogen Production Systems Based on Solar/Wind Hybrid Renewable Energies: A Case Study in Kuqa, China

Based on the concept of sustainable development, to promote the development and application of renewable energy and enhance the capacity of renewable energy consumption, this paper studies the design and optimization of renewable energy hydrogen production systems. For this paper, six different scenarios for grid-connected and off-grid renewable energy hydrogen production systems were designed and analyzed economically and technically, and the optimal grid-connected and off-grid systems were selected. Subsequently, the optimal system solution was optimized by analyzing the impact of the load data and component capacity on the grid dependency of the grid-connected hydrogen production system and the excess power rate of the off-grid hydrogen production system. Based on the simulation results, the most matched load data and component capacity of different systems after optimization were determined. The grid-supplied power of the optimized grid-connected hydrogen production system decreased by 3347 kWh, and the excess power rate of the off-grid hydrogen production system decreased from 38.6% to 10.3%, resulting in a significant improvement in the technical and economic performance of the system.