Pickup Process Research Articles

Cumulative livebirth rates (CLBR) per total number of oocytes employed in 11652 consecutive ovum donation (OD) cycles in a single center (2006-2011)

CLBR per total number of embryos transferred in consecutive cycles is a better approach than the raw livebirth rate per cycle to measure IVF success, but can be improved computing these rates per oocyte employed. The benefits of retrieving multiple oocytes per ovarian stimulation to optimize costly treatments, ovum pick-up and IVF processes needs to be properly characterized. Our aim was to describe CLBR per total number of oocytes employed to achieve livebirth in consecutive OD cycles.

Uptake of atmospheric molecules by ice nanoparticles: Pickup cross sections

Uptake of several atmospheric molecules on free ice nanoparticles was investigated. Typical examples were chosen: water, methane, NO(x) species (NO, NO(2)), hydrogen halides (HCl, HBr), and volatile organic compounds (CH(3)OH, CH(3)CH(2)OH). The cross sections for pickup of these molecules on ice nanoparticles (H(2)O)(N) with the mean size of N≈260 (diameter ~2.3 nm) were measured in a molecular beam experiment. These cross sections were determined from the cluster beam velocity decrease due to the momentum transfer during the pickup process. For water molecules molecular dynamics simulations were performed to learn the details of the pickup process. The experimental results for water are in good agreement with the simulations. The pickup cross sections of ice particles of several nanometers in diameter can be more than 3 times larger than the geometrical cross sections of these particles. This can have significant consequences in modelling of atmospheric ice nanoparticles, e.g., their growth.

Competing Fracture Modeling of Thin Chip Pick-Up Process

The IC chip ejecting and pick-up process in electronic assembly plays a critical role in advanced packaging since the success ratio and productivity are determined by the delamination of thin chips from the underlying substrate. For a chip-on-substrate structure subjected to a transverse concentrated load resulting from the ejecting needle, a competing relationship between chip peeling-off and chip cracking is discovered from the perspective of integral structure. A competing index, Γ, is defined to characterize the competing fracture behavior between cracking and peeling-off, and the competing fracture mechanism is then uncovered fundamentally. Based on the index, the effects of chip geometry on competing behavior are investigated using the virtual crack-closure technique with dummy nodes. Critical thickness and length, which separate chip peeling-off and cracking modes, are found and they represent the extremity of successful pick-up process. The critical values are determined by critical competing index, Γ - Γc. The competing mechanism uncovered applies to general pick-up process with various chip sizes and materials. The critical sizes and the method of evaluating critical values are meaningful for chip profile design, optimization of pick-up process, and propelling new designs of electronic assembly process, especially for thin chips.

Imaging and manipulation of adatoms on an alumina surface by noncontact atomic force microscopy

Noncontact atomic force microscopy (NC-AFM) has been performed on an aluminum oxide film grown on NiAl(110) in ultrahigh vacuum (UHV) at low temperature (5 K). Results reproduce the topography of the structural model, unlike scanning tunnelling microscopy (STM) images. Equipped with this extraordinary contrast the network of extended defects, which stems from domain boundaries intersecting the film surface, can be analysed in atomic detail. The knowledge of occurring surface structures opens up the opportunity to determine adsorption sites of individual adsorbates on the alumina film. The level of difficulty for such imaging depends on the imaging characteristics of the substrate and the interaction which can be maintained above the adsorbate. Positions of single adsorbed gold atoms within the unit cell have been determined despite their easy removal at slightly higher interaction strength. Preliminary manipulation experiments indicate a pick-up process for the vanishing of the gold adatoms from the film surface.

Nanofork for Single Cells Adhesion Measurement via ESEM-Nanomanipulator System

In this paper, single cells adhesion force was measured using a nanofork. The nanofork was used to pick up a single cell on a line array substrate inside an environmental scanning electron microscope (ESEM). The line array substrate was used to provide small gaps between the single cells and the substrate. Therefore, the nanofork could be inserted through these gaps in order to successfully pick up a single cell. Adhesion force was measured during the cell pick-up process from the deflection of the cantilever beam. The nanofork was fabricated using focused ion beam (FIB) etching process while the line array substrate was fabricated using nanoimprinting technology. As to investigate the effect of contact area on the strength of the adhesion force, two sizes of gap distance of line array substrate were used, i.e., 1 μm and 2 μm. Results showed that cells attached on the 1 μm gap line array substrate required more force to be released as compared to the cells attached on the 1 μm gap line array substrate.

Adhesion Performance and Microscope Morphology of UV-Curable Semi-interpenetrated Dicing Acrylic PSAs in Si-Wafer Manufacture Process for MCP

UV-curable acrylic pressure-sensitive adhesives (acrylic PSAs) have many applications in industry. As the Si-wafers become thinner, the acrylic PSAs for MCP need to show proper adhesion and leave little residue on the Si-wafer after UV irradiation when released from the dicing tapes. Strong adhesion is required in the dicing process to hold the Si-wafer before UV irradiation. On the other hand, weak adhesion strength is required after UV irradiation to prevent damage to the Si-wafers during the pick-up process. This study employed semi-interpenetrating polymer network-structured dicing of acrylic PSAs in the Si-wafer manufacture process. The binder PSAs contained 2-ethylhexyl acrylate (2-EHA) and acrylic acid (AA). The adhesion performance of the peel strength on a Si-wafer was examined as a function of the UV dose. The results showed that the abovementioned two requirements were achieved using semi-IPN dicing acrylic PSAs using a hexafunctional acrylate monomer and a UV-curing system. FE-SEM and XPS revealed little residue on the wafer after removing the tape. This paper suggests the optimal conditions for the curing agent, the additional hexafunctional monomer, photoinitiator and the coating thickness.

Clustering Pre-equilibrium Model Analysis for Nucleon-induced Alpha-particle Spectra up to 200 MeV

The clustering exciton model of Iwamoto and Harada is applied to the analy- sis of pre-equilibrium (N; x ) energy spectra for medium-to-heavy nuclei up to 200 MeV. In this work, we calculate alpha-particle formation factors without any approximations that appear in the original model. The clustering process is also considered in both the primary and second pre-equilibrium emissions. We optimize the exciton and the cluster- ing model parameters simultaneously by looking at the experimental (N; xN) and (N; x ) energy spectra. The experimental alpha-particle spectra are well reproduced with a unique set of clustering model parameters, which is independent of incident neutrons/protons. The present analysis also implies that the clustering model parameter is not so di erent between the medium and heavy nuclei. Our calculations reproduce experimental data gen- erally well up to the incident energy of 150 MeV, but underestimations are seen above this energy. The exciton model, as it is frequently used in the nuclear data evaluation (1), predicts pre-equilibrium (N; xN) spectra generally well. However, a long-standing problem exists in the model calculation of the pre-equilibrium composite-particle spectra due to rather complicated reaction mechanism. The phenomenological models proposed by Kalbach (2,3) describe nucleon-transfer reaction process in the phase-space, in which many adjustable parameters are involved to fit experimental particle energy- spectra. Although a useful global parameterization is reported (2,3), extrapolation of the global pa- rameters beyond the experimental range needs much attention. We apply the clustering exciton model of Iwamoto and Harada (4) to calculate nucleon-induced pre-equilibrium alpha-particle spectra from medium-to-heavy nuclei. The model describes the pickup process within the exciton model framework, where the alpha-particle formation factor is calculated by the overlap integral of wave functions between the alpha-particle and four nucleons (include the nu- cleons below Fermi level). In this work, the formation factors are calculated by numerical integrations, while the original Iwamoto-Harada model employed the root-mean-square approximation (4) where no correlation exists between the coordinates in the phase-space. The clustering process is also con- sidered in both the primary and second pre-equilibrium emissions. We optimize the pre-equilibrium and the clustering model parameters simultaneously by looking at the experimental nucleon and alpha- particle energy spectra. In this paper, di erences between the exact calculation and the approximation are exhibited for the alpha-particle formation factor. Through the comparisons with experimental spectra at incident energies up to 200 MeV, we show the behavior of the clustering model parameter, the applicability and limitation of the model.

Incident-energy dependence of the analyzing power in the58Ni(p,3He)56Co reaction between 80 and 120 MeV

This project looks at the angular distributions of the differential cross sections and analyzing powers of a few low lying states of 56 Co in the reaction 58 Ni(p, 3 He) 56 Co at three different incident energies between 80 and 120 MeV. The measurements are compared with zero-range distorted-wave Born approximation (DWBA) calculations in which we assume a simple direct two-nucleon pickup process. Earlier inclusive (p, 3 He) reaction studies on similar targets were successfully treated in terms of a statistical pre-equilibrium multistep formalism, in which the final stage of the reaction involved a deuteron pickup, described by means of the DWBA. The analyzing power was shown to be rather sensitive to the contributions of the different order steps. However some features observed in the analyzing powers of these inclusive studies, though reproduced by the theory, are not fully understood. We therefore investigate the ability of the DWBA model to describe the (p, 3 He) pickup reaction to discrete states at different incident energies using a high resolution spectrometer.

Ion Energization and Escape on Mars and Venus

Mars and Venus do not have a global magnetic field and as a result solar wind interacts directly with their ionospheres and upper atmospheres. Neutral atoms ionized by solar UV, charge exchange and electron impact, are extracted and scavenged by solar wind providing a significant loss of planetary volatiles. There are different channels and routes through which the ionized planetary matter escapes from the planets. Processes of ion energization driven by direct solar wind forcing and their escape are intimately related. Forces responsible for ion energization in different channels are different and, correspondingly, the effectiveness of escape is also different. Classification of the energization processes and escape channels on Mars and Venus and also their variability with solar wind parameters is the main topic of our review. We will distinguish between classical pickup and ‘mass-loaded’ pickup processes, energization in boundary layer and plasma sheet, polar winds on unmagnetized planets with magnetized ionospheres and enhanced escape flows from localized auroral regions in the regions filled by strong crustal magnetic fields.

Analysis of interfacial peeling in IC chip pick-up process

The IC chip–ejecting and pick-up process plays a critical role in advanced packages since the success ratio and productivity are determined by the delamination of the chip-on-substrate structure. The paper investigates analytically the interfacial peeling mechanism of a chip-on-substrate structure subjected to a transverse concentrated load resulting from ejecting needle from the fracture mechanics point of view. The effects of key factors, including chip size, initial crack length, and substrate material, are uncovered. Finite element calculations are performed to obtain the interfacial peeling energy-release rate by using virtual crack-closure technique with dummy nodes. Analytical formulas and numerical results match fairly well for the entire range of the chip length and the crack length. It is shown that the greater the ratio of length to thickness of the chip is, the smaller the energy-release rate is, and length is the more important factor than thickness to affect the peeling. It implies the interfacial peeling gets tougher for thin or big chips during the pick-up process. Second, as the crack grows, the peeling energy-release rate increases. Third, the softer the substrate is, the greater the peeling energy-release rate is under the action of a constant transverse load. For the pick-up of thin or big chips, in order to achieve high success rate and suppress damage to the chip, it is suggested that more compliant and thinner substrate be adopted, weaker adhesive strength be chosen, and multiple needles be used.

Direct Ionization of Large Proteins and Protein Complexes by Desorption Electrospray Ionization-Mass Spectrometry

Desorption electrospray ionization-mass spectrometry (DESI-MS) has advantages for rapid sample analysis with little or no sample pretreatment, but performance for large biomolecules has not been demonstrated. In this study, liquid sample DESI, an extended version of DESI used for analysis of liquid samples, was shown to have capabilities for direct ionization of large noncovalent protein complexes (>45 kDa) and proteins (up to 150 kDa). Protein complex ions (e.g., superoxide dismutase, enolase, and hemoglobin) desorbed from solution by liquid sample DESI were measured intact, indicating the capability of DESI for preserving weak noncovalent interactions. Doping the DESI spray solvent with supercharging reagents resulted in protein complex ions having increased multiple charging without complex dissociation. Ion mobility measurements of model protein cytochrome c showed that the supercharging reagent favored the more compact conformation for the lower charged protein ions. Liquid sample DESI of hydrophobic peptide gramicidin D suggests that the ionization mechanism involves a droplet pick-up mixing process. Measurement of liquid samples significantly extends the mass range of DESI-MS, allowing the analysis of high-mass proteins such as 150 kDa immunoglobulin G (IgG) and thus represents the largest protein successfully ionized by DESI to date.

Realization of Undistorted and Orthoscopic Integral Imaging Without Black Zone in Real and Virtual Fields

When integral imaging systems work in their conventional configuration, the reconstructed images are pseudoscopic. The two-step pickup process is capable of giving an orthoscopic image, but it involves black zones, which affect the viewing angle. We analyze the black zones on the elemental images. The improved two-step pickup process is proposed to solve this problem, and the mathematical models of the improved digital secondary pickup process without black zones are also proposed. The simulation and experiment are presented. An undistorted and orthoscopic 3-D scene without black zones is reconstructed in real and virtual fields simultaneously.

Generic camera model and its calibration for computational integral imaging and 3D reconstruction

Integral imaging (II) is an important 3D imaging technology. To reconstruct 3D information of the viewed objects, modeling and calibrating the optical pickup process of II are necessary. This work focuses on the modeling and calibration of an II system consisting of a lenslet array, an imaging lens, and a charge-coupled device camera. Most existing work on such systems assumes a pinhole array model (PAM). In this work, we explore a generic camera model that accommodates more generality. This model is an empirical model based on measurements, and we constructed a setup for its calibration. Experimental results show a significant difference between the generic camera model and the PAM. Images of planar patterns and 3D objects were computationally reconstructed with the generic camera model. Compared with the images reconstructed using the PAM, the images present higher fidelity and preserve more high spatial frequency components. To the best of our knowledge, this is the first attempt in applying a generic camera model to an II system.

Investigation of the Correlation between IC Chip Pick-Up Performance and Peeling Behavior of Adhesive Tapes

It was investigated that the influences of the peeling behavior of adhesive tapes in peeling tests on IC chip pick-up performance. Needles peel off an IC chip with an adhesive film from the base material in the pick-up process, by sticking out the backside of the base material. In the case that the peeling forces of the adhesive tape decrease as the peeling speeds increase in peeling tests, only two kinds of behaviors were observed in pick-up test; the peeling propagated little and the IC chip was not peeled off under critical needle displacement while the pick-up was completed instantaneously over critical needle displacement. In the case that the peeling forces of the adhesive tape increase as the peeling speeds increase, the pick-up time decreased as the needle displacement increased. As a result, it can be concluded that the needle displacement where the peeling propagates instantaneously is critical for succeeded pick-up if the peeling forces of the adhesive tape decrease as the peeling speeds increase. If the peeling forces of the adhesive tape increase as the peeling speeds increase, the information of peeling speeds at each needle displacement are needed to estimate how long it takes to pick-up a chip.

Estimation of Intracellular Calcium Ion Concentration by Nonlinear State Space Modeling and Expectation-Maximization Algorithm for Parameter Estimation

A calcium imaging method has superior ability in recording of spatial–temporal variations in ion concentration. However, it has two major problems. First, the imaging signals are very noisy. Second, the observation data are only the fluorescence intensities of Ca 2+ indicator dyes that provide indirect information about the Ca 2+ concentration. We develop a nonlinear state-space model for Ca imaging series involving Ca 2+ kinetics and a noisy fluorescence intensity pickup process. We devise recursive update algorithms for estimating the Ca 2+ concentration and Ca 2+ flux, and give the expectation-maximization algorithm for inferring model parameters.

Mechanisms of ionospheric mass escape

The dependence of ionospheric O+ escape flux on electromagnetic energy flux and electron precipitation into the ionosphere is derived for a hypothetical ambipolar pickup process, powered the relative motion of plasmas and neutral upper atmosphere, and by electron precipitation, at heights where the ions are magnetized but influenced by photo‐ionization, collisions with gas atoms, ambipolar and centrifugal acceleration. Ion pickup by the convection electric field produces “ring‐beam” or toroidal velocity distributions, as inferred from direct plasma measurements, from observations of the associated waves, and from the spectra of incoherent radar echoes. Ring beams are unstable to plasma wave growth, resulting in rapid relaxation via transverse velocity diffusion, into transversely accelerated ion populations. Ion escape is substantially facilitated by the ambipolar potential, but is only weakly affected by centrifugal acceleration. If, as cited simulations suggest, ion ring beams relax into nonthermal velocity distributions with characteristic speed equal to the local ion‐neutral flow speed, a generalized “Jeans escape” calculation shows that the escape flux of ionospheric O+ increases with Poynting flux and with precipitating electron density in rough agreement with observations.

합성 촬영 집적 영상의 신호 모델 해석 방법

SAII (synthetic aperture integral imaging) is a useful technique to record many multi view images of 3D objects by using a moving camera and to reconstruct 3D depth images from the recorded multiviews. This is largely composed of two processes. A pickup process provides elemental images of 3D objects and a reconstruction process generates 3D depth images computationally. In this paper, a signal model for SAII is presented. We defined the granular noise and analyzed its characteristics. Our signal model revealed that we could reduce the noise in the reconstructed images and increase the computational speed by reducing the shifting distance of a single camera.

TURBULENT HEATING OF THE DISTANT SOLAR WIND BY INTERSTELLAR PICKUP PROTONS IN A DECELERATING FLOW

Previous models of solar wind heating by interstellar pickup proton-driven turbulence have assumed that the wind speed is a constant in heliocentric radial position. However, the same pickup process, which is taken to provide the turbulent energy, must also decelerate the wind. In this paper, we extend our phenomenological turbulence model to include variable wind speed, and then incorporate the deceleration due to interstellar pickup protons into the model. We compare the model results with plasma and field data from Voyager 2, taking this opportunity to present an extended and improved data set of proton core temperature, magnetic field fluctuation intensity, and correlation length along the Voyager trajectory. A particular motivation for including the solar wind deceleration in this model is the expectation that a slower wind would reduce the resulting proton core temperature in the region beyond ~60 AU, where the previous model predictions were higher than the observed values. However, we find instead that the deceleration of the steady-state wind increases the energy input to the turbulence, causing even higher temperatures in that region. The increased heating is shown to result from the larger values of the ratio of Alfven speed to solar wind speed that develop in the decelerating wind.

Study on Peeling Behavior in Pick-up Process of IC Chip with Adhesive Tapes

A method to evaluate pick-up performance of four kinds of adhesive tape materials with different thickness has been studied numerically and experimentally. Needles peel an IC chip with an adhesive film off the base material in the pick-up process, by pushing the back of the base material. In our evaluation method, the dependence of the peel energy on the peel speed was measured using a peel test. The finite element method was applied to calculate the energy release rate of the pick-up process for various peel lengths. The pick-up time was obtained from the results of the peel tests and the finite element analysis. Our results indicate that the peel energy is the dominant property influencing the pick-up performance, and the difference in energy release rate in the pick-up process between the samples is not significant. Furthermore, the minimum needle displacement was estimated from the calculated pick-up time using our method. The minimum needle displacement of the experimental pick-up values was in good agreement with the estimated result.

USING DISCRETE EVENT SIMULATION TO EVALUATE THE BENEFITS OF RFID IN REDUCING TRAFFIC CONGESTION AND POLLUTION WHILE INCREASING STUDENT SAFETY IN RURAL OKLAHOMA SCHOOLS

In this paper, we used discrete-event simulation to evaluate the benefits of RFID to improve an afterschool pickup process. The setting was a rural town in Oklahoma that has seen rapid growth. In addition to reducing pickup times by 49%, demand management policies that convert spiky demand into level demand were shown to have benefits. Annual projected fuel savings due to less idling were estimated to be $3,000. Similarly, an annual reduction of 60 thousand pounds of CO2 was estimated. Although more difficult to quantify, our proposed RFID system is designed to increase safety and security. Further, the proposed system has the potential to reduce accidents by reducing parents’ frustration due to waiting. Security is further increased because RFID systems assist in parent verification.