Chip Type Research Articles

Rapid Determination of Trace Elements in Macedonian Grape Brandies for Their Characterization and Safety Evaluation

A graphite furnace atomic absorption spectrometry (GFAAS) was used for determination of trace elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in “rakija” samples, a grape brandy traditionally produced in Republic of Macedonia by distillation of grape pomace or wine, for characterization and safety evaluation. Cd, Pb, Cr, and Ni were determined directly, while Cu, Fe, Mn, and Zn were quantified after appropriate dilution. The calibration curves of all elements were linear with correlation coefficients (R 2) ranging from 0.9995 to 0.9998. The accuracy of the method was checked with a standard addition method showing good repeatability and reproducibility (relative standard deviation (RSD) <10 %). Relationship between several metal concentrations (Cu, Fe, Mn, Zn) in brandies and distillation system (homemade/industrial) on one side and aging mode (oak barrels/oak chips) on the other side were demonstrated. Two homemade brandies showed Cu, Fe, and Zn concentrations higher than industrial distillates and thus were found to be not safe for consumption because of Cu and Zn over the maximum allowed values. For the industrially produced brandies, Mn was identified to be a suitable marker related to aging with oak chips regardless variety, while Cu a marker for the influence of oak chip type. Principal component analysis applied on the content of elements clearly showed a good separation in terms of distillation and aging method.

Quantum-mechanical modeling of chip deformation and failure

An atomic approach to chip deformation and failure in cutting is outlined. The relation of the shear strength and the type of chip to the energy characteristics of the crystal lattice, its packing-defect energy, and the latent heat of fusion is established. The constancy of the shear with variation in the cutting conditions is related to the limiting dislocation density and the formation of an amorphous–liquid state.

Microelectrodes Integrated into a Microfluidic Chip for the Detection of CCRF‐CEM Cells Based on the Electrochemical Oxidation of Hydrazine

AbstractWe designed one type of microfluidic chip integrated with Au microelectrodes to detect target CCRF‐CEM cells based on the electrochemical oxidation of hydrazine catalyzed by Pt nanoparticles (NPs). The microelectrode can improve the sensitivity of detection, with a low background signal and decreased nonspecific adsorption. Applying the cell aptamer as the sensing element, this method exhibits good selectivity. Owing to the strong catalytic ability of Pt NPs for the electrochemical oxidation of hydrazine, the limit of detection of this method is ten cells. By adjusting the detection area of Au microelectrodes, this chip can detect a wide range of target cells. Besides, this method successfully detected the target cells doped in blood samples, indicating its potential application in clinical diagnosis.

Heat Transfer Characteristics in High Power LED Packaging

This study uses the T3Ster transient thermal resistance measuring device to investigate the effects to heat transfer performances from different LED crystal grains, packaging methods and heat-sink substrates through the experimental method. The experimental parameters are six different types of LED modules that are made alternatively with the crystal grain structure, the die attach method and the carrying substrate. The crystal grain structure includes the lateral type, flip chip type and vertical type. The die attach method includes silver paste and the eutectic structure. The carrying substrates are aluminum oxide (Alumina) and aluminum nitride (AIN) ceramic substrates and metal core PCB (MCPCB). The experimental results show that, under the conditions of the same crystal grain and die attach method, the thermal resistance values for the AIN substrate and the Alumina substrate are 2.1K/W and 5.1K/W, respectively and the total thermal resistance values are 7.3K/W and 10.8K/W. Compared to the Alumina substrate, the AIN substrate can effectively lower the total thermal resistance value by 32.4%. This is because the heat transfer coefficient of the AIN substrate is higher than that of the Alumina substrate, thus effectively increasing its thermal conductivity. In addition, under the conditions of the same crystal grain and the same substrate, the packaging methods are using silver paste and the eutectic structure for die attach. Their thermal resistance values are 5.7K/W and 2.7K/W, respectively, with a variance of 3K/W. Comparisons of the crystal grain structure show that the thermal resistance for the flip chip type is lower than that of the traditional lateral type by 0.9K/W. This is because the light emitting layer of the flip chip crystal grain is closer to the heat-sink substrate, shortening the heat dissipation route, and thus lowering the thermal resistance value. For the total thermal resistance, the crystal grain structure has a lesser effect to the heat dissipation performance whereas the packaging method and the choice of the substrate have a relatively higher effect to the LED heat dissipation performance. Combining the above results, we see that selecting the flip chip crystal grain with a closer light emitting layer to the substrate, the eutectic structure that has better thermal conductivity and the AIN substrate can effectively increase the heat dissipation performance of the LED module.

Effects of External Hydrostatic Pressure on Orthogonal Cutting Characteristics

In this paper, effects of external hydrostatic pressure on the cutting characteristics are investigated. Orthogonal cutting experiments are conducted in a high pressure chamber using four kinds of materials; two of them are brittle materials and the others are ductile materials. Chip formation processes of soda glass specimen are studied by in-situ observation. It is confirmed that chip formation style changes from the crack type to the segmented chip type, then to the continuous chip type with the increase of hydrostatic pressure. Furthermore, cutting forces under various hydrostatic pressures are measured, and effects of hydrostatic pressure on the cutting forces are studied. It is found that hydrostatic pressure increases the cutting force in the brittle mode cutting of glasses, but does not affect the cutting force in ductile mode cutting. In case of ductile materials, hydrostatic pressure increases the cutting force of polycarbonate too, but does not affect the cutting force of pure aluminum. Based on those experimental results, mechanism of hydrostatic pressure effects on cutting characteristics is discussed.

Adaptive Neuro-Fuzzy Structure Based Control Architecture

The purpose of this paper is to present a practical application of a Sugeno model based adaptive neuro-fuzzy architecture. The main challenge of the project was to realize the real-time control of the system and the real-time parameter adaptation of the controller. The neuro-fuzzy controller module is implemented using High Level Synthesis technique, and it's integrated into a microprocessor based architecture on a System on Chip (SoC) type integrated circuit. The architecture is used to control a two degrees of freedom system, which is composed of two horizontal arms attached to a linear bearing. The bearing is running on a vertical beam so the system can execute a vertical motion and a rotary motion around the vertical axle. The positions according to the two degrees of freedom are determined using an ultrasonic and a magnetic sensor.

Sustainability Improvement in Milling Operation Through Improved Tool Design and Optimized Process Parameters-an Industrial Case Study

Current machining practice in a South-East England SME was studied over a 6 month period. This was preceded by exploratory academic research in sustainable machining and a set of short industrial observations/interviews. Preliminary machining tests conducted in the industry on Delrin, aluminium, carbon steel, stainless steel and Inconel 718 indicated more energy savings would be desirable with Inconel. New cutting tools were developed with potential to reduce energy consumption and tested on various features. The effect of using a trochoidal toolpath was also investigated. The results show that energy reduction was obtained for some of the features. Surface finish and tool wear and quality of type of chip produced were not impaired. The results have raised awareness of the potential for energy reduction in the SME and a major tool manufacturer involved in the study. The study has acted as exploration of factors important in the dissemination of sustainable machining in industry.

Anomaly detection with low magnetic flux: A fluxgate sensor network application

Recent studies on remote detection methods were mostly for improving variables like sensing distance, sensitivity and power consumption. Especially using anisotropic magneto-resistive sensors with low power consumption and high sensitivity for detecting subsurface magnetic materials became very popular in last decades. In our study, for detecting subsurface materials, we have used fluxgate sensor network for having even higher sensitivity and also minimizing the power consumption by detecting the changing rates of horizontal component of earth’s magnetic flux which is assumed to be very low. We have constituted a magnetic measurement system which comprises a detector system, which has a mechanism enables sensors to move in 3-D space, a data acquisition module for processing and sending all sensor information, and a computer for running the magnetic flux data evaluation and recording software. Using this system, tests are carried out to detect anomalies on horizontal component of earth’s magnetic flux which is created by different subsurface materials with known magnetic, chemical and geometric properties. The harmonics of horizontal component of earth’s magnetic flux in scanned area are analyzed by the help of DSP Lock-In amplifier and the amplitudes of high variation harmonics are shown as computer graphics. Using the graphic information, the upside surface geometry of subsurface material is defined. For identifying the magnetic anomalies, we have used the scale-invariant feature transform (SIFT)–binary robust invariant scalable keypoints (BRISKs) as keypoint and descriptor. We used an algorithm for matching the newly scanned image to the closest image in database which is constituted of mines and possible other metal objects like cans, etc. Results show that, if the proposed detection system is used instead of metal detectors which cannot distinguish mines from other metal materials and alert for every type of metal with different geometries, it can be said that miss alarm count, work force and time can be decreased dramatically. In this paper, mostly the setup of the system is described and in Appendix A some experimental outputs of the system for different geometries of metal samples are given. And also for comparing the results of the proposed system, additional experiments are carried out with a different type of sensor chip, namely KMZ51, and also given in Appendix A.

Molecularly Imprinted Polymer Arrays as Synthetic Protein Chips Prepared by Transcription-type Molecular Imprinting by Use of Protein-Immobilized Dots as Stamps

Molecularly imprinted polymer (MIP) arrays were demonstrated for the recognition of proteins. They were prepared via transcription-type molecular imprinting where patterned dots composed of biotinylated nanoparticles were first immobilized on a glass substrate followed by the immobilization of versatile biotinylated proteins via avidin-biotin interactions, yielding a multiple protein-immobilized stamp as a mold that could be transcribed. MIPs were prepared between the stamp and a methacrylated glass substrate, and after the stamp was peeled off, MIP dots were able to be prepared on the methacrylated glass substrate according to the positions of the immobilized proteins on the stamp. We confirmed that the prepared MIP array showed the expected selective binding toward the corresponding template proteins by conducting competitive binding assays using the fluorescently labeled proteins as corresponding competitors. The binding behaviors were consistent with those obtained by a surface plasmon resonance sensing system. We believe that the proposed platform involving the easily handled nanoparticle-based protein stamps for the preparation of MIP arrays can provide a new type of pattern recognition-based protein chip, which can be adopted as a substitute for the use of conventional protein arrays in various research and industrial fields in the life sciences.

Applications of Lipid Nanodiscs for the Study of Membrane Proteins by Surface Plasmon Resonance.

Methods for the initial steps of surface plasmon resonance analysis of membrane proteins incorporated in lipid nanodiscs are described. Several types of Biacore sensor chips are available and require distinct strategies to immobilize proteonanodiscs on the chip surface. The procedures for immobilization on three of these chips (NTA, antibody coupled CM5, and L1) are described in this unit and results are demonstrated for a model system with cytochrome P4503A4 (CYP3A4) in nanodiscs binding to a polyclonal anti-CYP3A4 antibody. Advantages and disadvantages of each chip type are considered.

Individual identification of pigs during rearing and at slaughter using microchips

Identification of individual pigs is essential for management, traceability, breeding, trading and disease control in commercial pig production. Conventional identification methods used for pigs, such as ear tags and tattoos, are not sufficiently reliable due to losses and code erasing. This study investigated the retention rate, functionality and tissue damage of microchips compared with conventional electronic ear tags and assessed the effects of chip size and pig age at microchip injection. A larger proportion of small (95.2%) than large (82.5%) microchips were readable throughout the rearing period (p<0.031). It was better to inject microchips when the piglets were 9–10 weeks old compared with 1–2 weeks (p=0.058). Ear tags caused significantly more tissue damage than microchips (p=0.001). However, although microchips met the requirements of an identification system for pigs that is unique, easy to read, does not produce apparent disturbance to the animals and causes minimal pathological changes, the proportion of lost microchips was unacceptably high. Further research on chip type, pig age at marking and marking site is needed to find suitable methods for identification of individual pigs.

The investigation of mechanism of serrated chip formation under different cutting speeds

Chip type is determined by the coupled effects of workpiece material property, cutting speed, uncut chip thickness, feed rate, and tool edge geometry. The understanding of chip formation plays a critical role in studying surface integrity and optimization of machining process variables. Serrated chip, one of the major important chip type, is usually formed in hard cutting at high speed. In this study, a new analytical model has been proposed to better understand the formation of serrated chip, and the simulations have been acquired using ABAQUS/Explicit in machining AISI 1045 during different speeds (from 60 to 6000 m/min). The workpiece material property is modeled with the Johnson-Cook model, and the experiments have been conducted with AISI 1045 during speeds from 60 to 1200 m/min. It has been shown that flow stress is influenced simultaneously by the strain rate hardening and temperature softening. When the speed reaches very high, the temperature softening will fail, and the strain rate hardening will play a more important role. Also, it can be found that the hardening ratio increases when the cutting speed rises. The results of the simulations and experiments correlated well. The cutting force and thrust force both decrease as the cutting speed increases, and the difference between them will shrink when the machining speed reaches a high level.

Effect of high hyperbaric pressure on rock cutting process

When cutting rock hyperbaric, two cases may occur. The rock may encounter dilation or compaction due to shear. Dilation results in pore under pressures, while compaction results in pore overpressures. Dilation will increase the cutting forces considerably, while compaction may decrease the cutting forces. In both cases the cutting process is supposed to be cataclastic. To dimension cutting tools for deep sea mining, the worst case should be investigated, which is the dilatant case. To understand the cutting mechanism experiments are carried out in a pressure tank, simulating the hyperbaric conditions. Hyperbaric cutting appears to be very different from atmospheric cutting due to the pore water pressures. The experiments have revealed that the cutting mechanism changes from a chip type mechanism under atmospheric conditions to a cataclastic (crushed) type under hyperbaric conditions, resulting in higher cutting forces.An analytical model is presented to estimate the cutting forces under high hyperbaric conditions. The results obtained with the analytical model agree rather well with the experimental data.

Direct immunosensing by spectral correlation interferometry: assay characteristics versus antibody immobilization chemistry.

A 3-channel biosensor based on spectral correlation interferometry (SCI) has been adapted for direct optical detection of antigens by measuring changes in thickness of a biolayer on functionalized glass slips employed as affordable single-use sensor chips. The instrument is insensitive to the bulk refractive index of a solution under test and provides signals in metrological units (pm or nm). Using real-time monitoring with the SCI, protocols for fabrication of sensor chips with different functional (epoxylated, carboxylated, and biotinylated) surfaces for antibody immobilization have been developed and optimized to minimize chip-to-chip variations and achieve better limit of detection (LOD), shorter assay time, and longer shelf life. The optimized coupling surfaces have been compared for detection of human serum albumin (HSA) used as a model agent of medical significance. The dynamic ranges for measuring the HSA concentration were 0.07-20, 0.12-30, and 0.25-10 μg/ml, and the assay durations were less than 20, 15, and 30 min for the epoxylated, carboxylated, and biotinylated chips, respectively. The advantages of each type of sensor chip have been shown, namely, the carboxylated chips feature the shortest assay time, the epoxylated ones demonstrate the best LOD, and the biotinylated chips exhibit the longest shelf life in an unprotected environment. The developed protocols of antibody immobilization can be used in different biosensors and assay techniques including those based on fluorescent, magnetic or plasmonic labels, etc. The SCI is well compatible with various partially transparent layers used in biosensing and with microarrays for multi-analyte detection.

10501 Lemaitreの損傷モデルを用いたFEM鋸歯状切りくず生成シミュレーション

The serrated type of chip is formed by the occurrence of the localization of the plastic shear deformation, hi order to simulate the serrated type of chip formation, this study has considered Lemaitre's damage model. In Lemaitre model, there is only one parameter to control the damage rate. The damage rate will have a correlation with a value of the ductile fracture strain that is affected by both the stress triaxiality and Lode angle. Hence, this study considered the dependence of the stress triaxiality and Lode angle on the parameter. The numerical experiments were conducted by assuming three kinds of model for the parameter. A model that considers the effect of the reduction of the damage under high temperature and high compression as well as the effect of the stress triaxiality and Lode angle obtained appropriate chip formation.

Process planning considerations for micromilling of mould cavities used in ultrasonic moulding technology

The current trend in miniaturization of products and components requires appropriate technologies for the manufacture of miniature dies and moulds. The work presented here deals with the process planning of micromilling for the production of miniature mould cavities, required in ultrasonic moulding in order to reach high precision. Several aspects of process planning are addressed, including cutting tool geometry selection, segmentation of cavity geometry, minimum chip thickness, chordal tolerance, and type of interpolation. The case study involves the successful micromilling of a complex aluminium mould cavity for ultrasonic moulding. The proposed process plan is demonstrated through the micromilling of the mould cavity and silicone replicas of the miniature geometrical model. In general terms, good precision is obtained following the proposed methodology. In a randomly located set of geometric features, the dimensional error was below 5% for most features (32 out of a total of 40).

Machinability Study on Dry Drilling of Titanium Alloy Ti-6Al-4V using L9 Orthoganal Array

In modern manufacturing technology, a lot of extensive research work has been carried out in drilling operations for achieving better hole quality. Drilling is one such machining processes which is widely used in aeronautical and automotive industries for structural assembly. Titanium alloy (Ti-6Al-4V) is attractive for many applications due to their superior properties. However, they are regarded as hard-to-machine materials. Drilling is an important machining process since it is involved in nearly all Titanium alloy applications. It is desirable to develop cost-effective drilling processes for Titanium alloy and improve the cost- effectiveness of currently-available processes. In the view of above facts, an attempt has been made to study the machinability during dry drilling of Ti-6Al-4V. The main objective of this study is to determine the favourable drilling conditions for Ti-6Al- 4V hole quality (surface roughness, and burr) and chip type based on design of experiments.

Heat Transfer Characteristics in High Power LED Packaging

This study uses the T3Ster transient thermal resistance measuring device to investigate the effects to heat transfer performances from different LED crystal grains, packaging methods and heat-sink substrates through the experimental method. The experimental parameters are six different types of LED modules that are made alternatively with the crystal grain structure, the die attach method and the carrying substrate. The crystal grain structure includes the lateral type, flip chip type and vertical type. The die attach method includes silver paste and the eutectic structure. The carrying substrates are aluminum oxide (Alumina) and aluminum nitride (AIN) ceramic substrates and metal core PCB (MCPCB). The experimental results show that, under the conditions of the same crystal grain and die attach method, the thermal resistance values for the AIN substrate and the Alumina substrate are 2.1K/W and 5.1K/W, respectively and the total thermal resistance values are 7.3K/W and 10.8K/W. Compared to the Alumina substrate, the AIN substrate can effectively lower the total thermal resistance value by 32.4%. This is because the heat transfer coefficient of the AIN substrate is higher than that of the Alumina substrate, thus effectively increasing its thermal conductivity. In addition, under the conditions of the same crystal grain and the same substrate, the packaging methods are using silver paste and the eutectic structure for die attach. Their thermal resistance values are 5.7K/W and 2.7K/W, respectively, with a variance of 3K/W. Comparisons of the crystal grain structure show that the thermal resistance for the flip chip type is lower than that of the traditional lateral type by 0.9K/W. This is because the light emitting layer of the flip chip crystal grain is closer to the heat-sink substrate, shortening the heat dissipation route, and thus lowering the thermal resistance value. For the total thermal resistance, the crystal grain structure has a lesser effect to the heat dissipation performance whereas the packaging method and the choice of the substrate have a relatively higher effect to the LED heat dissipation performance. Combining the above results, we see that selecting the flip chip crystal grain with a closer light emitting layer to the substrate, the eutectic structure that has better thermal conductivity and the AIN substrate can effectively increase the heat dissipation performance of the LED module.

Principal component analysis for feature extraction and NN pattern recognition in sensor monitoring of chip form during turning

Experimental cutting tests on C45 carbon steel turning were performed for sensor fusion based monitoring of chip form through cutting force components and radial displacement measurement. A Principal Component Analysis algorithm was implemented to extract characteristic features from acquired sensor signals. A pattern recognition decision making support system was performed by inputting the extracted features into feed-forward back-propagation neural networks aimed at single chip form classification and favourable/unfavourable chip type identification. Different neural network training algorithms were adopted and a comparison was proposed.

Estimating autozygosity from high-throughput information: effects of SNP density and genotyping errors

BackgroundRuns of homozygosity are long, uninterrupted stretches of homozygous genotypes that enable reliable estimation of levels of inbreeding (i.e., autozygosity) based on high-throughput, chip-based single nucleotide polymorphism (SNP) genotypes. While the theoretical definition of runs of homozygosity is straightforward, their empirical identification depends on the type of SNP chip used to obtain the data and on a number of factors, including the number of heterozygous calls allowed to account for genotyping errors. We analyzed how SNP chip density and genotyping errors affect estimates of autozygosity based on runs of homozygosity in three cattle populations, using genotype data from an SNP chip with 777 972 SNPs and a 50 k chip.ResultsData from the 50 k chip led to overestimation of the number of runs of homozygosity that are shorter than 4 Mb, since the analysis could not identify heterozygous SNPs that were present on the denser chip. Conversely, data from the denser chip led to underestimation of the number of runs of homozygosity that were longer than 8 Mb, unless the presence of a small number of heterozygous SNP genotypes was allowed within a run of homozygosity.ConclusionsWe have shown that SNP chip density and genotyping errors introduce patterns of bias in the estimation of autozygosity based on runs of homozygosity. SNP chips with 50 000 to 60 000 markers are frequently available for livestock species and their information leads to a conservative prediction of autozygosity from runs of homozygosity longer than 4 Mb. Not allowing heterozygous SNP genotypes to be present in a homozygosity run, as has been advocated for human populations, is not adequate for livestock populations because they have much higher levels of autozygosity and therefore longer runs of homozygosity. When allowing a small number of heterozygous calls, current software does not differentiate between situations where these calls are adjacent and therefore indicative of an actual break of the run versus those where they are scattered across the length of the homozygous segment. Simple graphical tests that are used in this paper are a current, yet tedious solution.