On Finding an Equivalent Force to Mimic the Multilayer Ceramic Capacitor Vibration

The Multilayer Ceramic Capacitor (MLCC) Can Vibrate Due to the Piezoelectric Effect When There is AC Noise on the Power Rail. the Vibration of the Capacitor Will Generate a Force on the PCB and Thus Cause the PCB Vibration and Audible Problems May Occur. the Work in This Paper Finds an Equivalent Force with Similar Behavior to the MLCC-Generated Force. the Force is Controllable and Knowable and Thus Can Mimic the Capacitor Vibration on the PCB

Monotonic Neural Ordinary Differential Equation: Time-series Forecasting for Cumulative Data

Time-Series Forecasting based on Cumulative Data (TSFCD) is a crucial problem in decision-making across various industrial scenarios. However, existing time-series forecasting methods often overlook two important characteristics of cumulative data, namely monotonicity and irregularity, which limit their practical applicability. To address this limitation, we propose a principled approach called Monotonic neural Ordinary Differential Equation (MODE) within the framework of neural ordinary differential equations. By leveraging MODE, we are able to effectively capture and represent the monotonicity and irregularity in practical cumulative data. Through extensive experiments conducted in a bonus allocation scenario, we demonstrate that MODE outperforms state-of-the-art methods, showcasing its ability to handle both monotonicity and irregularity in cumulative data and delivering superior forecasting performance.Comment: Accepted as CIKM'23 Applied Research Trac

Cross-View Retrieval via Probability-Based Semantics-Preserving Hashing

For efficiently retrieving nearest neighbors from large-scale multiview data, recently hashing methods are widely investigated, which can substantially improve query speeds. In this paper, we propose an effective probability-based semantics-preserving hashing (SePH) method to tackle the problem of cross-view retrieval. Considering the semantic consistency between views, SePH generates one unified hash code for all observed views of any instance. For training, SePH first transforms the given semantic affinities of training data into a probability distribution, and aims to approximate it with another one in Hamming space, via minimizing their Kullback-Leibler divergence. Specifically, the latter probability distribution is derived from all pair-wise Hamming distances between to-be-learnt hash codes of the training data. Then with learnt hash codes, any kind of predictive models like linear ridge regression, logistic regression, or kernel logistic regression, can be learnt as hash functions in each view for projecting the corresponding view-specific features into hash codes. As for out-of-sample extension, given any unseen instance, the learnt hash functions in its observed views can predict view-specific hash codes. Then by deriving or estimating the corresponding output probabilities with respect to the predicted view-specific hash codes, a novel probabilistic approach is further proposed to utilize them for determining a unified hash code. To evaluate the proposed SePH, we conduct extensive experiments on diverse benchmark datasets, and the experimental results demonstrate that SePH is reasonable and effective

Experimental study on the response relationship between environmental DNA concentration and biomass of Schizothorax prenanti in still water

The superiority of the environmental DNA (eDNA) method for estimating the biomass of aquatic species has been demonstrated. However, the relationship between eDNA concentration and biomass is difficult to clarify under the influence of complex water flow and habitat conditions. It seriously restricts the popularization and application of the eDNA method in estimating aquatic biomass. In this paper, a typical fish species of rivers in southwest China, Schizothorax prenanti, was selected as the target species. Under standardized laboratory hydrostatic conditions, two environmental factors, water pH and water temperature were firstly determined through pre-experiments. Then we investigated the correlation between eDNA concentration and biomass under different body sizes and different body size compositions. The experimental results showed that water pH and the water temperature had a great influence on eDNA concentration. Therefore, the effects of these environmental factors need to be considered simultaneously when using eDNA concentration to estimate biomass. Under the premise of consistent environmental conditions, the biomass of Schizothorax prenanti was positively correlated with the eDNA concentration when the individual body size was the same. For each 1% increase in biomass of the fish, the eDNA concentration of adult (larger size) fish increased by 0.98%, while the eDNA concentration of juvenile (smaller size) fish increased by 1.38%. The smaller the size of individual fish, the greater the increase of eDNA concentration with biomass, and the increase of juvenile fish was about 1.4 times that the adult fish. When the biomass was the same but the body size composition was different, the higher the proportion of small body size individuals in the population, the higher the eDNA concentration. Special attention needs to be paid to the body size composition of the population to avoid the biomass estimation being lower than the actual value when the smaller size fish are dominant. The experimental results provide a strong basis for a more accurate estimation of aquatic biomass in reservoirs, lakes, and other still water areas by using the eDNA method

Equivalent Force Extraction Methodology For Electrical Component Induced PCB Vibration

On-board electrical components can cause printed circuit board (PCB) vibration, thus generating audio noise if the electrical noise is in the audible frequency range. The electrical component-induced vibration can be equated to an external force applied to the PCB. This article presents a novel methodology to extract the equivalent force of electrical components on a PCB to study board vibration and potential acoustic noise problems. The method is based on a combination of measurement and simulation, wherein PCB vibration is used as the medium in the extraction process. The methodology is validated by the correlation of PCB vibration pattern, frequency, and amplitude with a known electromagnetic force applied to the PCB

FORCE2: A state-of-the-art two-phase code for hydrodynamic calculations

A three-dimensional computer code for two-phase flow named FORCE2 has been developed by Babcock and Wilcox (B W) in close collaboration with Argonne National Laboratory (ANL). FORCE2 is capable of both transient as well as steady-state simulations. This Cartesian coordinates computer program is a finite control volume, industrial grade and quality embodiment of the pilot-scale FLUFIX/MOD2 code and contains features such as three-dimensional blockages, volume and surface porosities to account for various obstructions in the flow field, and distributed resistance modeling to account for pressure drops caused by baffles, distributor plates and large tube banks. Recently computed results demonstrated the significance of and necessity for three-dimensional models of hydrodynamics and erosion. This paper describes the process whereby ANL's pilot-scale FLUFIX/MOD2 models and numerics were implemented into FORCE2. A description of the quality control to assess the accuracy of the new code and the validation using some of the measured data from Illinois Institute of Technology (UT) and the University of Illinois at Urbana-Champaign (UIUC) are given. It is envisioned that one day, FORCE2 with additional modules such as radiation heat transfer, combustion kinetics and multi-solids together with user-friendly pre- and post-processor software and tailored for massively parallel multiprocessor shared memory computational platforms will be used by industry and researchers to assist in reducing and/or eliminating the environmental and economic barriers which limit full consideration of coal, shale and biomass as energy sources, to retain energy security, and to remediate waste and ecological problems

DualTeacher: Bridging Coexistence of Unlabelled Classes for Semi-supervised Incremental Object Detection

In real-world applications, an object detector often encounters object instances from new classes and needs to accommodate them effectively. Previous work formulated this critical problem as incremental object detection (IOD), which assumes the object instances of new classes to be fully annotated in incremental data. However, as supervisory signals are usually rare and expensive, the supervised IOD may not be practical for implementation. In this work, we consider a more realistic setting named semi-supervised IOD (SSIOD), where the object detector needs to learn new classes incrementally from a few labelled data and massive unlabelled data without catastrophic forgetting of old classes. A commonly-used strategy for supervised IOD is to encourage the current model (as a student) to mimic the behavior of the old model (as a teacher), but it generally fails in SSIOD because a dominant number of object instances from old and new classes are coexisting and unlabelled, with the teacher only recognizing a fraction of them. Observing that learning only the classes of interest tends to preclude detection of other classes, we propose to bridge the coexistence of unlabelled classes by constructing two teacher models respectively for old and new classes, and using the concatenation of their predictions to instruct the student. This approach is referred to as DualTeacher, which can serve as a strong baseline for SSIOD with limited resource overhead and no extra hyperparameters. We build various benchmarks for SSIOD and perform extensive experiments to demonstrate the superiority of our approach (e.g., the performance lead is up to 18.28 AP on MS-COCO). Our code is available at \url{https://github.com/chuxiuhong/DualTeacher}

Equivalent Source Investigation For PCB Vibration Excited By A Multilayer Ceramic Capacitor

Multilayer ceramic capacitors (MLCCs) are commonly used on printed circuit board (PCB) power distribution networks (PDN) for decoupling purposes. However, an MLCC can act as a source to excite PCB vibrations due to noise ripples on the power rail. In this letter, four types of equivalent source configurations are studied and compared to represent the excitation of an MLCC on a PCB driven by power rail noise. The corresponding source values are extracted at test-vehicle PCB resonance frequencies. The investigation of the four equivalent source types involves a comparison between simulated and measured PCB vibration velocity responses triggered by MLCC deformation across an audible frequency band. The advantages of each equivalent source are discussed for specific application scenarios