A Temperature – and Supply- Variation Robust 2nd-Order Sigma-Delta Modulation for Capacitive Sensing

Capacitance to digital converter, VCO quantizer, Sigma-Delta modulation, Supply variation, temperature variationIn this paper, I proposed a temperature- and supply variation robust 2nd-order sigma-delta modulation circuit for capacitive sensing. Capacitive sensing by conventional circuits is basically supply sensitive. Capacitance is sensed by reading the charge that is equal to the difference between the capacitance value of the capacitor and the capacitor to be sensed. In this method, the amount of charge is dependent on the supply, so it is insensitive to supply variation. In this paper, the capacitance is read by using the time determined by the discharge characteristics when a capacitor called T0V meets the resistance component. The charge accumulated in the capacitor is certainly influenced by the supply value, but capacitive sensing is performed using the characteristic that the time taken to discharge the charge to zero is always constant. In the process, VCO (Voltage-Controlled-Oscillator) based ADC (Analog-to-Digital Converter) was used to increase the resolution by utilizing the noise shaping effect of sigma-delta ADC. In the process, the resistor is switched to a switched capacitor to obtain robust characteristics against temperature variations. Unlike resistance whose values change with temperature, capacitance are relatively robust to temperature effects. By using the characteristics, a circuit having robust characteristics in temperature variation as well as robust in supply variation.openAbstract i List of contents iii List of figures iv List of figures v Ⅰ. Introduction 1.1 Motivation and Objective 1 1.2 Theses outline 3 ⅠI. Supply- Variation Robust 2nd-Order Sigma-Delta Modulation 2.1 Supply Independent Technique 4 2.2 Injection Locking Current Controlled Oscillator 8 2.3 VCO Based ADC 13 2.4 Full Architecture 16 2.4.1 Control Block 19 2.4.2 Block Diagram 21 2.5 Schematic and Layout 23 III. Temperature- and Supply- Variation Robust 2nd-Order Sigma-Delta Modulation 3.1 Switched Capacitor DAC 31 3.2 Switched Capacitor Clock Generator 36 3.3 Control Block 38 3.4 Schematic 39 IV. Simulation and Measurement Result 4.1 Resistor DAC Circuit 42 4.1.1 Measurement Result 42 4.2 Switched Capacitor DAC Circuit 45 4.2.1 Simulation Result 45 V. Conclusion본 논문은 전원변화 및 온도변화에도 안정적으로 정전용량을 읽어낼 수 있는 2차 시그마-델타 변조기 회로이다. 커패시터의 방전 시간이 전원의 영향이 아닌 정전용량과 저항 값에만 영향을 받는다는 점을 이용하여 회로를 구성하였다. 또한 저항이 온도변화에 따라서 일정한 값을 유지하기 힘들다는 점을 보완하기위해 switched capacitor 기법을 사용하였다. 커패시터는 저항에 비해 상대적으로 온도변화에도 정전용량을 안정적인 값으로 유지할 수 있다. 이 점을 이용하여 전원변화뿐 만이 아닌 온도변화에도 강인한 특성을 가질 수 있게 된다. 또 전압제어발진기를 활용한 아날로그-디지털 변환기법도 사용되었다. 전압제어발진기에 ‘전압제어발진기 기반 양자화기’라는 양자화를 할 수 있는 회로를 연결하여 동작이 진행된다. 이 기법을 사용하게 되면 양자화오류의 성분들이 백색잡음처럼 모든 주파수대역에 걸쳐서 골고루 존재하는 것이 아닌, 고주파 쪽을 향해 20dB의 기울기를 가지며 상승하는 형태로 나타난다. 최종적인 전체 루프의 특성을 확인하면 40dB의 기울기를 가지며 상승하는 형태를 갖는다. 이 특성을 통하여 동작 대역폭이 아닌 더 고주파 영역으로 양자화 오류 성분들을 밀어낼 수 있다는 장점이 있다. 그 결과, SNR이 상승하게 되어 최종적으로 정전용량을 읽어낼 수 있는 분해능 성능이 좋아지게 된다.MasterdCollectio

Invariant subspaces for operators whose spectra are Carathéodory regions

AbstractIn this paper it is shown that if an operator T satisfies ‖p(T)‖⩽‖p‖σ(T) for every polynomial p and the polynomially convex hull of σ(T) is a Carathéodory region whose accessible boundary points lie in rectifiable Jordan arcs on its boundary, then T has a nontrivial invariant subspace. As a corollary, it is also shown that if T is a hyponormal operator and the outer boundary of σ(T) has at most finitely many prime ends corresponding to singular points on ∂D and has a tangent at almost every point on each Jordan arc, then T has a nontrivial invariant subspace

MatGD: Materials Graph Digitizer

We have developed MatGD (Material Graph Digitizer), which is a tool for digitizing a data line from scientific graphs. The algorithm behind the tool consists of four steps: (1) identifying graphs within subfigures, (2) separating axes and data sections, (3) discerning the data lines by eliminating irrelevant graph objects and matching with the legend, and (4) data extraction and saving. From the 62,534 papers in the areas of batteries, catalysis, and MOFs, 501,045 figures were mined. Remarkably, our tool showcased performance with over 99% accuracy in legend marker and text detection. Moreover, its capability for data line separation stood at 66%, which is much higher compared to other existing figure mining tools. We believe that this tool will be integral to collecting both past and future data from publications, and these data can be used to train various machine learning models that can enhance material predictions and new materials discovery.Comment: 23 pages, 4 figure

ARM MOTIONS FOR DIFFERENT TARGET POSITIONS DURING TAEKWONDO ROUNDHOUSE KICKS

The purpose of this study was to investigate arm motions for five different target positions during Taekwondo roundhouse kicks. Nine Taekwondo experts performed roundhouse kicks at a target. A 3D motion analysis was conducted. One-way repeated ANOVA was used to compare the arm motion among five conditions. This study reveals that a higher kick needs the increased vertical separation of the right and left arm (elbow and wrist) in release phase. For a longer kick at Body level, elbows should be more vertically apart and wrists should be more horizontally apart in the release phase. Both attackers and counter attackers in Taekwondo athletes can use the arm swing characteristics at different target heights and distances

EFFECTS OF FOOT PLACEMENT ON RESULTANT JOINT MOMENTS OF LOWER EXTREMITY JOINTS DURING SQUAT

The purpose of this study was to investigate the effects of foot placement (stance width and foot angle) on normalized sagittal- and frontal-plane resultant joint moments (NRJM) of the lower extremity joints during the squat. Forty-two participants were recruited: male (n = 21) and female (n = 21). Three-dimensional motion analysis and inverse dynamics analysis were conducted. There was a significant interaction between the stance width and foot angle on the NRJM in the sagittal plane, whereas there were significant main effects of the stance width, foot angle, and gender on the NRJM in the frontal plane

ELVIS: Empowering Locality of Vision Language Pre-training with Intra-modal Similarity

Deep learning has shown great potential in assisting radiologists in reading chest X-ray (CXR) images, but its need for expensive annotations for improving performance prevents widespread clinical application. Visual language pre-training (VLP) can alleviate the burden and cost of annotation by leveraging routinely generated reports for radiographs, which exist in large quantities as well as in paired form (imagetext pairs). Additionally, extensions to localization-aware VLPs are being proposed to address the needs of accurate localization of abnormalities for CAD in CXR. However, we find that the formulation proposed by locality-aware VLP literatures actually leads to loss in spatial relationships required for downstream localization tasks. Therefore, we propose Empowering Locality of VLP with Intra-modal Similarity, ELVIS, a VLP aware of intra-modal locality, to better preserve the locality within radiographs or reports, which enhances the ability to comprehend location references in text reports. Our locality-aware VLP method significantly outperforms state-of-the art baselines in multiple segmentation tasks and the MS-CXR phrase grounding task. Qualitatively, ELVIS is able to focus well on regions of interest described in the report text compared to prior approaches, allowing for enhanced interpretability.Comment: Under revie

ANALYSIS OF THE TRUNK/SHOULDER COMPLEX MOTION DURING THE GOLF DRIVES USING A 5-SEGMENT TRUNK/SHOULDER MODEL

The purpose of this study was to quantify detailed trunk/shoulder complex motions during the golf drives using a new 5-segment trunk/shoulder model (pelvis, abdomen, thorax, and right/left shoulder girdles) and to describe the patterns of the relative motions of the trunk/shoulder segments. Fifteen male golfers were divided into two groups: skilled (n=8, 3-handicap or better) and less skilled (n=7, 13- to 18-handicap). The ranges of the orientation angles of the segments during the downswing were computed. In addition to the dominant rotation of the thorax, substantial frontal plane motions of the trunk segments (abdomen and thorax) and transverse plane motions of the shoulder girdles were observed. Only the frontal plane motion of the left shoulder girdle (elevation/depression) was identified as the factor which differentiated the groups

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C-ITS Environment Modeling and Attack Modeling

As technology advances, cities are evolving into smart cities, with the ability to process large amounts of data and the increasing complexity and diversification of various elements within urban areas. Among the core systems of a smart city is the Cooperative-Intelligent Transport Systems (C-ITS). C-ITS is a system where vehicles provide real-time information to drivers about surrounding traffic conditions, sudden stops, falling objects, and other accident risks through roadside base stations. It consists of road infrastructure, C-ITS centers, and vehicle terminals. However, as smart cities integrate many elements through networks and electronic control, they are susceptible to cybersecurity issues. In the case of cybersecurity problems in C-ITS, there is a significant risk of safety issues arising. This technical document aims to model the C-ITS environment and the services it provides, with the purpose of identifying the attack surface where security incidents could occur in a smart city environment. Subsequently, based on the identified attack surface, the document aims to construct attack scenarios and their respective stages. The document provides a description of the concept of C-ITS, followed by the description of the C-ITS environment model, service model, and attack scenario model defined by us.Comment: in Korean Language, 14 Figures, 15 Page