scholarly journals Rapid 3D-Imaging of Semiconductor Chips Using THz Time-of-Flight Technique

2021 ◽  
Vol 11 (11) ◽  
pp. 4770
Author(s):  
Jong Hyuk Yim ◽  
Su-yeon Kim ◽  
Yiseob Kim ◽  
Suyoung Cho ◽  
Jangsun Kim ◽  
...  
Keyword(s):  
High Speed ◽  
Signal To Noise Ratio ◽  
3D Structure ◽  
Three Dimensional ◽  
Time Of Flight ◽  
Scanning Speed ◽  
Frequency Component ◽  
Image Resolution ◽  
Imaging Tool ◽  
Semiconductor Chips

In this study, we developed a rapid three-dimensional (3D) time-of-flight imaging tool for inspection of packaged semiconductor chips, using terahertz (THz) time-domain spectroscopy techniques. A high-speed THz system based on the optical sampling by cavity tuning technique is incorporated with a 2-axis galvano scanner to deliver a scanning speed of more than 100 Hz/pixel with a signal-to-noise ratio larger than 20 dB. Through the use of the Hilbert transformation, we reconstruct the 3D structure of the packaged chip in a nondestructive manner. Additionally, the use of frequency-selective imaging allows us to manipulate image resolution; the higher resolution was obtained when monitored using the higher frequency component. Further, using phase information, we were able to detect and identify defects in the packaged chip, such as the delamination area and epoxy-rich regions.

Cryomicroscopy of crotoxin complex crystals at 400 KV

1989 ◽  
Vol 47 ◽  
pp. 826-827
Author(s):  
Jaap Brink ◽  
Wah Chiu
Keyword(s):  
Signal To Noise Ratio ◽  
3D Structure ◽  
Three Dimensional ◽  
Carbon Films ◽  
Depth Of Field ◽  
Basic Subunit ◽  
Ewald Sphere ◽  
Diffraction Patterns ◽  
Complex Crystals ◽  
Acidic Subunit

The crotoxin complex is a potent neurotoxin composed of a basic subunit (Mr = 12,000) and an acidic subunit (M = 10,000). The basic subunit possesses phospholipase activity whereas the acidic subunit shows no enzymatic activity at all. The complex's toxocity is expressed both pre- and post-synaptically. The crotoxin complex forms thin crystals suitable for electron crystallography. The crystals diffract up to 0.16 nm in the microscope, whereas images show reflections out to 0.39 nm2. Ultimate goal in this study is to obtain a three-dimensional (3D-) structure map of the protein around 0.3 nm resolution. Use of 100 keV electrons in this is limited; the unit cell's height c of 25.6 nm causes problems associated with multiple scattering, radiation damage, limited depth of field and a more pronounced Ewald sphere curvature. In general, they lead to projections of the unit cell, which at the desired resolution, cannot be interpreted following the weak-phase approximation. Circumventing this problem is possible through the use of 400 keV electrons. Although the overall contrast is lowered due to a smaller scattering cross-section, the signal-to-noise ratio of especially higher order reflections will improve due to a smaller contribution of inelastic scattering. We report here our preliminary results demonstrating the feasability of the data collection procedure at 400 kV.Crystals of crotoxin complex were prepared on carbon-covered holey-carbon films, quench frozen in liquid ethane, inserted into a Gatan 626 holder, transferred into a JEOL 4000EX electron microscope equipped with a pair of anticontaminators operating at −184°C and examined under low-dose conditions. Selected area electron diffraction patterns (EDP's) and images of the crystals were recorded at 400 kV and −167°C with dose levels of 5 and 9.5 electrons/Å, respectively.

On the 3D Structure of Elasticity-Induced Unstable Flow in the Curved Microchannel by Using Confocal Micro-PIV and Polarized Camera

2015 ◽  
Author(s):  
Xiao-Bin Li ◽  
Masamichi Oishi ◽  
Marie Oshima ◽  
Feng-Chen Li ◽  
Song-Jing Li
Keyword(s):  
Flow Rate ◽  
High Speed ◽  
3D Structure ◽  
Three Dimensional ◽  
Working Fluid ◽  
Wall Region ◽  
Unstable Flow ◽  
Solution Flow ◽  
Micro Particle Image Velocimetry ◽  
Micro Piv

In this paper, the three-dimensional (3D) structures of a micellar solution flow in the curvilinear microchannel have been investigated by means of confocal micro particle image velocimetry (PIV). The working fluid is aqueous solution of CTAC/NaSal (cetyltrimethylammonium / Sodium Salysilate). As the flow rate increases, the flow gradually gets into the irregular motion. It is found that the inside flow seems not completely chaotic, but in a manner of oscillation. To be specific, the flow nonlinearity grows as the flow rate increases, the inside flow shows different structures near the wall region and in the bulk due to the elongation of viscoelastic surfactant. Typically, two sub-streams were twisted together, and their flow directions change at the locations where the signs of geometric curvature change. The oscillation stripes represented the area of high extensional stress in the viscoelastic fluid, and were further identified by using polarized high-speed camera. Moreover, statistics shows that the viscoelastic flow field inside the curved microchannel shares the main features of elastic turbulence.

scholarly journals Reconstruction of Three-Dimensional Conformations of Bacterial ClpB from High-Speed Atomic-Force-Microscopy Images

2021 ◽  
Vol 8 ◽  
Author(s):  
Bhaskar Dasgupta ◽  
Osamu Miyashita ◽  
Takayuki Uchihashi ◽  
Florence Tama
Keyword(s):  
Atomic Force Microscopy ◽  
Computational Modeling ◽  
High Speed ◽  
3D Structure ◽  
Three Dimensional ◽  
3D Models ◽  
Computational Method ◽  
Molecular Surface ◽  
Force Microscopy ◽  
Atomic Force

ClpB belongs to the cellular disaggretase machinery involved in rescuing misfolded or aggregated proteins during heat or other cellular shocks. The function of this protein relies on the interconversion between different conformations in its native condition. A recent high-speed-atomic-force-microscopy (HS-AFM) experiment on ClpB from Thermus thermophilus shows four predominant conformational classes, namely, open, closed, spiral, and half-spiral. Analyses of AFM images provide only partial structural information regarding the molecular surface, and thus computational modeling of three-dimensional (3D) structures of these conformations should help interpret dynamical events related to ClpB functions. In this study, we reconstruct 3D models of ClpB from HS-AFM images in different conformational classes. We have applied our recently developed computational method based on a low-resolution representation of 3D structure using a Gaussian mixture model, combined with a Monte-Carlo sampling algorithm to optimize the agreement with target AFM images. After conformational sampling, we obtained models that reflect conformational variety embedded within the AFM images. From these reconstructed 3D models, we described, in terms of relative domain arrangement, the different types of ClpB oligomeric conformations observed by HS-AFM experiments. In particular, we highlighted the slippage of the monomeric components around the seam. This study demonstrates that such details of information, necessary for annotating the different conformational states involved in the ClpB function, can be obtained by combining HS-AFM images, even with limited resolution, and computational modeling.

scholarly journals Single-Sided Near-Field Wireless Power Transfer by A Three-Dimensional Coil Array

Micromachines ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 200 ◽  
Author(s):  
Amirhossein Hajiaghajani ◽  
Seungyoung Ahn
Keyword(s):  
Magnetic Field ◽  
Printed Circuit Boards ◽  
Signal To Noise Ratio ◽  
Near Field ◽  
3D Structure ◽  
Three Dimensional ◽  
Power Transfer ◽  
Circuit Boards ◽  
Wireless Power ◽  
Halbach Arrays

Wirelessly powered medical microrobots are often driven or localized by magnetic resonance imaging coils, whose signal-to-noise ratio is easily affected by the power transmitter coils that supply the microrobot. A controlled single-sided wireless power transmitter can enhance the imaging quality and suppress the radiation leakage. This paper presents a new form of electromagnet which automatically cancels the magnetic field to the back lobes by replacing the traditional circular coils with a three-dimensional (3D) coil scheme inspired by a generalized form of Halbach arrays. It is shown that, along with the miniaturization of the transmitter system, it allows for improved magnetic field intensity in the target side. Measurement of the produced magnetic patterns verifies that the power transfer to the back lobe is 15-fold smaller compared to the corresponding distance on the main lobe side, whilst maintaining a powering efficiency similar to that of conventional planar coils. To show the application of the proposed array, a wireless charging pad with an effective powering area of 144 cm2 is fabricated on 3D-assembled printed circuit boards. This 3D structure obviates the need for traditional magnetic shield materials that place limitations on the working frequency and suffer from non-linearity and hysteresis effects.

scholarly journals Optimization of 3D Point Clouds of Oilseed Rape Plants Based on Time-of-Flight Cameras

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 664
Author(s):  
Zhihong Ma ◽  
Dawei Sun ◽  
Haixia Xu ◽  
Yueming Zhu ◽  
Yong He ◽  
...  
Keyword(s):  
Stress Responses ◽  
Average Distance ◽  
3D Structure ◽  
Three Dimensional ◽  
Time Of Flight ◽  
Bilateral Filter ◽  
Point Clouds ◽  
3D Point Clouds ◽  
Plant Data ◽  
Tof Camera

Three-dimensional (3D) structure is an important morphological trait of plants for describing their growth and biotic/abiotic stress responses. Various methods have been developed for obtaining 3D plant data, but the data quality and equipment costs are the main factors limiting their development. Here, we propose a method to improve the quality of 3D plant data using the time-of-flight (TOF) camera Kinect V2. A K-dimension (k-d) tree was applied to spatial topological relationships for searching points. Background noise points were then removed with a minimum oriented bounding box (MOBB) with a pass-through filter, while outliers and flying pixel points were removed based on viewpoints and surface normals. After being smoothed with the bilateral filter, the 3D plant data were registered and meshed. We adjusted the mesh patches to eliminate layered points. The results showed that the patches were closer. The average distance between the patches was 1.88 × 10−3 m, and the average angle was 17.64°, which were 54.97% and 48.33% of those values before optimization. The proposed method performed better in reducing noise and the local layered-points phenomenon, and it could help to more accurately determine 3D structure parameters from point clouds and mesh models.

scholarly journals Deep Learning For Denoising Hi-C Chromosomal Contact Data

2019 ◽  
Author(s):  
Max Highsmith ◽  
Oluwatosin Oluwadare ◽  
Jianlin Cheng
Keyword(s):  
Deep Learning ◽  
Signal To Noise Ratio ◽  
Pearson Correlation ◽  
3D Structure ◽  
Three Dimensional ◽  
Yeast Genome ◽  
Chromosome Conformation ◽  
Contact Matrix ◽  
The Impact

AbstractMotivationThe three-dimensional (3D) organization of an organism’s genome and chromosomes plays a significant role in many biological processes. Currently, methods exist for modeling chromosomal 3D structure using contact matrices generated via chromosome conformation capture (3C) techniques such as Hi-C. However, the effectiveness of these methods is inherently bottlenecked by the quality of the Hi-C data, which may be corrupted by experimental noise. Consequently, it is valuable to develop methods for eliminating the impact of noise on the quality of reconstructed structures.ResultsWe develop unsupervised and semi-supervised deep learning algorithms (i.e. deep convolutional autoencoders) to denoise Hi-C contact matrix data and improve the quality of chromosome structure predictions. When applied to noisy synthetic contact matrices of the yeast genome, our network demonstrates consistent improvement across metrics for contact matrix similarity including: Pearson Correlation, Spearman Correlation and Signal-to-Noise Ratio. Positive improvement across these metrics is seen consistently across a wide space of parameters to both gaussian and poisson noise [email protected] and [email protected]

Biomedical Application of Multimodal Ultrasound Microscope

2012 ◽  
pp. 27-35
Author(s):  
Yoshifumi Saijo
Keyword(s):  
Acoustic Impedance ◽  
High Frequency ◽  
Sound Speed ◽  
High Speed ◽  
Biomedical Application ◽  
3D Structure ◽  
Three Dimensional ◽  
Single Pulse ◽  
Frequency Domain Analysis ◽  
High Frequency Ultrasound

High frequency ultrasound imaging has evolved from the classical acoustic microscope to the multimodal ultrasound microscope, which is available for quantitative C-mode, surface acoustic impedance mode, and three-dimensional (3D)-mode imaging. This evolution has realized both quantitative parametric imaging and easier observation. Quantitative C-mode represents two-dimensional sound speed distribution and is realized by frequency-domain analysis of a single pulse by a high-speed digitizer. Because the square of sound speed is proportional to tissue elasticity, sound speed imaging provides biomechanical information about the tissue. Surface acoustic impedance mode has been used to image fresh brain tissue. High-frequency 3D-mode imaging has been used to visualize the 3D structure of dermis sebaceous glands.

scholarly journals Interactive 3D Navigation System for Image-guided Surgery

2009 ◽  
Vol 8 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Huy Hoang Tran ◽  
Kiyoshi Matsumiya ◽  
Ken Masamune ◽  
Ichiro Sakuma ◽  
Takeyoshi Dohi ◽  
...  
Keyword(s):  
Navigation System ◽  
High Speed ◽  
3D Structure ◽  
Three Dimensional ◽  
Surgical Instruments ◽  
Surface Model ◽  
Surface Rendering ◽  
3D Navigation ◽  
Registration Method ◽  
Interactive 3D

This paper presents a novel surgery navigation system based on a three-dimensional (3D) imaging technique, integral videography (IV). In our system, the 3D structure of the object of interest is reconstructed using surface rendering and corresponding pixel distribution methods. We developed a high-speed algorithm that renders high-quality IV images from the surface model in real time and allows interactions like rotating and scaling to be done smoothly. Using the patient-image registration method, IV images can be displayed with the correct size and relative position with respect to the surgical instruments. Experiments were carried out with various anatomical models, and the results show that our system could be useful in many clinical situations such as orthopedic surgery and neurosurgery.

scholarly journals X-Ray Flow Visualization in Multiphase Flows

2021 ◽  
Vol 53 (1) ◽  
pp. 543-567
Author(s):  
Alberto Aliseda ◽  
Theodore J. Heindel
Keyword(s):  
Flow Visualization ◽  
Multiphase Flows ◽  
Signal To Noise Ratio ◽  
3D Structure ◽  
Three Dimensional ◽  
High Volume ◽  
Operating Conditions ◽  
Time Resolved ◽  
X Ray ◽  
Optical Visualization

The use of X-ray flow visualization has brought a powerful new tool to the study of multiphase flows. Penetrating radiation can probe the spatial concentration of the different phases without the refraction, diffraction, or multiple scattering that usually produce image artifacts or reduce the signal-to-noise ratio below reliable values in optical visualization of multiphase flows; hence, X-ray visualization enables research into the three-dimensional (3D) structure of multiphase flows characterized by complex interfaces. With the commoditization of X-ray laboratory sources and wider access to synchrotron beam time for fluid mechanics, this novel imaging technique has shed light onto many multiphase flows of industrial and environmental interest under realistic 3D configurations and at realistic operating conditions (high Reynolds numbers and high volume fractions) that had defied study for decades. We present a broad survey of the most commonly studied multiphase flows (e.g., sprays, fluidized beds, bubble columns) in order to highlight the progress X-ray imaging has made in understanding the internal structure and multiphase coupling of these flows, and we discuss the potential of advanced tomography and time-resolved and particle tracking radiography for further study of multiphase flows.

Methods for three-dimensional reconstruction of cellular components within a thick section

1986 ◽  
Vol 44 ◽  
pp. 18-21
Author(s):  
J. Frank ◽  
B. F. McEwen ◽  
M. Radermacher ◽  
C. L. Rieder
Keyword(s):  
Tilt Angle ◽  
Tomographic Reconstruction ◽  
3D Structure ◽  
Three Dimensional ◽  
Thick Section ◽  
Three Dimensional Reconstruction ◽  
Axis Ratio ◽  
Dimensional Reconstruction ◽  
Cellular Components

The tomographic reconstruction from multiple projections of cellular components, within a thick section, offers a way of visualizing and quantifying their three-dimensional (3D) structure. However, asymmetric objects require as many views from the widest tilt range as possible; otherwise the reconstruction may be uninterpretable. Even if not for geometric obstructions, the increasing pathway of electrons, as the tilt angle is increased, poses the ultimate upper limitation to the projection range. With the maximum tilt angle being fixed, the only way to improve the faithfulness of the reconstruction is by changing the mode of the tilting from single-axis to conical; a point within the object projected with a tilt angle of 60° and a full 360° azimuthal range is then reconstructed as a slightly elliptic (axis ratio 1.2 : 1) sphere.

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