Direct Observation and Quantitative Analysis of the Fiber Formation Process during Electrospinning by a High-Speed Camera

2018 ◽  
Vol 57 (36) ◽  
pp. 12122-12126 ◽  
Author(s):  
Ikuo Uematsu ◽  
Kenya Uchida ◽  
Yasutada Nakagawa ◽  
Hidetoshi Matsumoto
Keyword(s):  
Quantitative Analysis ◽  
Direct Observation ◽  
Formation Process ◽  
High Speed ◽  
Fiber Formation ◽  
High Speed Camera

Effect of Process Parameters on Free Air Ball Integrity in Copper and Palladium-coated Copper Bonding Wires

2014 ◽  
Vol 2014 (1) ◽  
pp. 000272-000277
Author(s):  
Noritoshi Araki ◽  
Yasutomo Ichiyama ◽  
Ryo Oishi ◽  
Teruo Haibara ◽  
Takashi Yamada
Keyword(s):  
Process Parameters ◽  
Formation Process ◽  
High Speed ◽  
High Speed Camera ◽  
Formation Processes ◽  
Shielding Gas ◽  
Optimization Of Process Parameters ◽  
Free Air ◽  
Bonding Wires ◽  
High Density Packaging

The Free Air Ball (FAB) formation processes of fine diameter Cu wires were observed, and the effects of process parameters were studied on the basis of high-speed camera observation. It was revealed that the FAB formation process is characterized by preheating before melting, melting that accompanies ball rising, and solidification periods. The relationships between the electronic flame-off (EFO) condition and the FAB formation were summarized for both bare Cu and palladium-coated Cu wires. Further study was performed on the changes in FAB shape with different EFO conditions, wire types, and FAB sizes. Off-centered FABs were observed in the bare Cu wire whereas they were rarely observed in the Pd-coated Cu wire. The off-center tended to be affected by shielding gas condition, EFO torch gap, and FAB size. The mechanisms of the off-centered FAB formation were proposed through the high speed camera observations. The optimization of process parameters to achieve defect-free, consistent FAB is discussed based on these findings, which is useful for the next generation high density packaging.

A Quantitative Analysis of Flagellar Movement in Echinoderm Spermatozoa

1978 ◽  
Vol 76 (1) ◽  
pp. 85-104 ◽  
Author(s):  
YUKIO HIRAMOTO ◽  
SHOJI A. BABA
Keyword(s):  
Quantitative Analysis ◽  
High Speed ◽  
Single Equation ◽  
Entire Length ◽  
High Speed Camera ◽  
Sine Function ◽  
Active Force ◽  
Bending Waves ◽  
The Waves ◽  
Flagellar Axoneme

Computerized analyses were performed on the movement of spermatozoa recorded with a high-speed camera. These provide evidence for active bending waves over the entire length of the flagellum and a single equation for waves in all cases examined. In the equation, the angular direction of the flagellum at any distance from the base is expressed by a sine function of time plus a constant, and thus flagellar waves are ‘sine-generated’. To explain the waves a model was proposed in which the active force required to generate sliding between peripheral microtubules is propagated along and around the flagellar axoneme.

Effect of Process Parameters on Free Air Ball Integrity in Copper and Palladium-Coated Copper Bonding Wires

2015 ◽  
Vol 12 (2) ◽  
pp. 98-103
Author(s):  
Noritoshi Araki ◽  
Yasutomo Ichiyama ◽  
Ryo Oishi ◽  
Teruo Haibara ◽  
Takashi Yamada
Keyword(s):  
Process Parameters ◽  
Formation Process ◽  
High Speed ◽  
High Speed Camera ◽  
Formation Processes ◽  
Shielding Gas ◽  
Optimization Of Process Parameters ◽  
Free Air ◽  
Bonding Wires ◽  
High Density Packaging

The free air ball (FAB) formation processes of fine diameter Cu wires were observed, and the effects of process parameters were studied on the basis of high-speed camera observation. It was revealed that the FAB formation process is characterized by preheating before melting, melting that accompanies ball rising, and solidification periods. The relationships between the electronic flame-off (EFO) condition and the FAB formation were summarized for both bare Cu and palladium-coated Cu (PCC) wires. Further study was performed on the changes in FAB shape with different EFO conditions, wire types, and FAB sizes. Off-centered FABs were observed in the bare Cu wire whereas they were rarely observed in the PCC wire. The off-center tended to be affected by shielding gas condition, EFO torch gap, and FAB size. The mechanisms of the off-centered FAB formation were proposed through the high-speed camera observations. The optimization of process parameters to achieve defect-free, consistent FAB is discussed based on these findings, which is useful for the next generation high-density packaging.

Kinetics of elastic twinning in calcite

1962 ◽  
Vol 270 (1343) ◽  
pp. 525-537 ◽  
Keyword(s):  
Activation Energy ◽  
Shear Stress ◽  
Direct Observation ◽  
High Speed ◽  
High Speed Camera ◽  
Temperature Range ◽  
Applied Shear Stress ◽  
Velocity Of Propagation ◽  
Twin Propagation ◽  
Kinetics Of

An investigation of the effect of localized transient stresses on calcite is described. It is shown that twinning may or may not occur, depending on the duration of the stress pulse, the temperature and a factor related to the length of twin which may be formed. An hypothesis is suggested to explain the results and, from it, the velocity of propagation of twin lamellae is calculated in the temperature range from 20 to 300 °C. An activation energy for twin propagation is also calculated. Direct observation of the twinning process using a high-speed camera has confirmed the above hypothesis and results and has shown that the velocity of propagation of twin lamellae in calcite is not very dependent on the applied shear stress.

scholarly journals Particle Track and Trace during Membrane Filtration by Direct Observation with a High Speed Camera

Membranes ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 68
Author(s):  
Mads Koustrup Jørgensen ◽  
Kristian Boe Eriksen ◽  
Morten Lykkegaard Christensen
Keyword(s):  
Direct Observation ◽  
High Speed ◽  
Membrane Filtration ◽  
Hollow Fiber Membrane ◽  
Membrane Surface ◽  
Fluid Velocity ◽  
High Speed Camera ◽  
Particle Track ◽  
Particle Rotation ◽  
Particle Velocities

A methodology was developed for direct observation and analysis of particle movements near a microfiltration membrane. A high speed camera (1196 frames per second) was mounted on a microscope to record a hollow fiber membrane in a filtration cell with a transparent wall. Filtrations were conducted at varying pressure and crossflow velocities using synthetic core–shell particles (diameter 1.6 μm) of no and high negative surface charge. MATLAB scripts were developed to track the particle positions and calculate velocities of particle movements across and towards the membrane surface. Data showed that the velocity of particles along the membrane increases with distance from the membrane surface which correlates well with a fluid velocity profile obtained from CFD modelling. Particle track and trace was used to calculate the particle count profiles towards the membrane and document a higher concentration of particles near the membrane surface than in the bulk. Calculation of particle velocity towards and away from the membrane showed a region within 3–80 μm from the membrane surface with particle velocities higher than expected from the velocity of water through the membrane, thus the permeation drag underpredicts the actual velocity of particles towards the membrane. Near the membrane, particle velocities shift direction and move away. This is not described in classical filtration theory, but it has been speculated that this is an effect of particle rotation or due to membrane vibration or change in flow pattern close to the membrane.

Movement characteristics of micro drill bit during entry period in PCB high speed drilling

Circuit World ◽  
2016 ◽  
Vol 42 (3) ◽  
pp. 110-116 ◽  
Author(s):  
Hongyan Shi ◽  
Qiuxin Yan ◽  
Shengzhi Chen
Keyword(s):  
Quantitative Analysis ◽  
High Speed ◽  
Spindle Speed ◽  
Drill Bit ◽  
High Speed Camera ◽  
Content Type ◽  
Entry Period ◽  
Movement Characteristics ◽  
High Speed Drilling ◽  
Micro Drill

Purpose The purpose of this paper is to study the movement characteristics of micro drill bit during entry period in printed circuit board (PCB) high-speed drilling and to present an effective method to conduct quantitative analysis of the wandering of drill bit based on high-speed video capturing. Design/methodology/approach Based on the high-speed camera technology, experiments are conducted to get a series of time sequence images and the wandering of micro drill tip and the radial run-out of drill body, and the max-deformation of drill bit are calculated by using a quantitative analysis method. Finally, the movement characteristics of micro drill bit during entry drilling period PCB high-speed drilling are evaluated. Findings With the increasing spindle speed, the radial run-out of drill body decreases gradually, whereas the wandering amplitude of the drill point gradually increases; micro drill bit itself has an ability of positioning deviation correction after contacting the entry sheet; the feed rate within a certain range could slightly worsen the deformation of drill tip at the instant of impingement. Research limitations/implications With the improvement of spindle speed, the camera’s shooting speed needed will increase accordingly, thus, the resolution of the pictures will decline, which always affects the analysis precision. Originality/value A series of effective methods to conduct quantitative analysis of the wandering micro drill bit by using high-speed camera technology is presented; a reference for the optimization of micro-hole drilling is provided.

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