In-house Prototype Research Articles

Sustainable Energy Outlook: Biodiesel from Used Cooking Oil in Palestine

Developing alternatives to fossil fuels has become increasingly essential due to the ongoing depletion of non-renewable energy sources worldwide. Biodiesel, a promising substitute for fossil fuels, is not only environmentally friendly but also compatible with diesel engines. The process of converting used vegetable oils or animal fats into biodiesel is known as transesterification. In order to increase Palestine's potential for renewable energy and attain energy independence, biodiesel could be used as a renewable resource. This study focuses on the viability of developing a home appliance that can transform used cooking oil into biodiesel appropriate for domestic usage. Currently, used cooking oil is disposed of inappropriately in Palestine, causing serious environmental harm. Palestine stands to gain by addressing this environmental problem and making it simpler to use used cooking oil as a renewable energy source. Therefore, the main objective of this study is to create a machine that is simple to operate, affordable in comparison to other devices on the market, and needs minimal maintenance. An in-house prototype was built at An-Najah National University's workshop for 4,500 NIS (or roughly $1,320). In addition, a number of lab tests were performed to assess the characteristics of the cooking oil and the required reaction conditions, such as temperature, mixing rate, and the right catalyst. According to the findings, the created machine has a production cost that is 25% lower than that of conventional diesel while maintaining a comparable level of performance in diesel engines. This study opens the door for a long-term solution to Palestine's energy problems and environmental problems.

Point-of-Care Diagnosis on Selenium Nutrition Based on Time-Resolved Fluorometric Glycoaffinity Chromatography.

Given the lack of timely evaluation of the well-received selenium fortification, a neat lateral-flow chromatographic solution was constructed here by using the recently identified urinary selenosugar (Sel) as a strongly indicative marker. As there are no ready-made receptors for this synthetic standard, phenylboronic acid (PBA) esterification and Dolichos biflorus agglutinin (DBA) affinity joined up to pinch and pin down the analyte into a sandwich-type glycol complex. Pilot lectin screening on homemade glycan microarrays verified such a new pairing between dual recognizers as PBA-Sel-DBA with a firm monosaccharide-binding constant. To quell the sample autofluorescence, europium nanoparticles with efficient long-life afterglow were employed as conjugating probes under 1 μs excitation. After systematic process optimizations, the prepared Sel-dipstick achieved swift and sensitive fluorometry over the physiological level of the target from 0.1 to 10 μM with a detection limit down to 0.06 μM. Further efforts were made to eliminate matrix effects from both temperature and pH via an approximate formula. Upon completion, the test strips managed to quantify the presence of Sel in not just imitated but real human urine, with comparable results to those in the references. As far as we know, this would be the first in-house prototype for user-friendly and facile diagnosis of Se nutrition with fair accuracy as well as selectivity. Future endeavors will be invested to model a more traceable Se-supplementary plan based on the rhythmic feedback of Sel excretion.

Gas Analysis of Large-Format Automotive Lithium-Ion Battery Cells during Formation

Due to the decision by the European Union to stop sales of combustion-based vehicles after 2035, all car manufacturers are in search to close this gap with alternative solutions. As Lithium-Ion batteries (LIBs) are already an integral part of our everyday life, battery based electric vehicles (BEVs) are expected to be one possible alternative for the individual mobility of tomorrow. Therefore, all original equipment manufacturers (OEMs) who want to produce their own battery cells must deal with many challenges as the LIB is the most expensive single component used in EVs. Reducing costs of LIB production is making EVs more affordable and even more sustainable. One major production-related factor is the dwell-time under dry-room conditions as its disproportionately increases the overall production costs. Dry-Room conditions can´t be avoided as materials like the electrolyte and active material rely on water-free handling conditions [2-3, 5].Battery cells are typically assembled in a dry state. Cells are then filled with electrolyte and a so-called precharge step is performed. During this, the solid-electrolyte interface (SEI) is formed on the negative electrode when the electrolyte is partially reduced. The formation process results in a significant gas evolution, where typical gasses like CO, CO2, H2, O2, C2H4 can be formed [1, 4, 5]. After main gas evolution, the cells can be sealed and transported into normal atmosphere, where further charging and evaluation protocols are performed. In order to understand the voltage-related gas evolution during first charging, new analytical methods are needed. The hyphenation of electrochemical cycling and mass spectrometry to so-called Online-Electrochemical Mass Spectrometry (OEMS) is a powerful technique to investigate the gas evolution inside LIBs.In this project the development of OEMS for large-format prismatic LIBs will be outlined. The feasibility of studying battery cell formation reactions and the influence of typical parameters, like temperature or charging rate onto the gassing rate will be discussed. The obtained experiments are designed to give new insights into the gas formation during first charge and how the results compare in size to already well described model-cell OEMS-experiments [2, 3]. The cells are based on a graphite / NMC811 system with ethylene carbonate (EC) and ethyl methyl carbonate (EMC) 5/7 w% (LP57-electrolyte). The cells are produced by our BMW inhouse prototype production line and provide a clear as simple composition of all components. In contrast, commercially available LIBs differ in many aspects, e.g., containing a complex mixture of different volatile organic carbonates as well as quite often unknown additives, which may complicate the analysis [4]. The inhouse production also allows a unique integration of a commercially available Swagelok fitting in the lid of the LIB.

Experimental and computational investigation of Mg AZ31 grain refinement by shear-enhanced rolling

Magnesium (Mg) alloys have been actively researched to replace various steel and aluminum alloys in the automotive, aerospace, and defense industries. However, their inferior formability needs improvement to compete with these alloys. For instance, in the case of rolling, conventional grain refinement produces surface layers of a finer grain structure while the core of thick rolled sections remains substantially coarser. This work introduces shear-enhanced rolling (SER) to overcome this issue and correspondingly enhance formability. SER applies a transverse load (TL) between two conventional rolling stations to induce high shearing stresses at the section core. An experimental study is done here on an Mg AZ31B alloy using an in-house prototype to prove the concept of SER. Experimental specimens are then tested to identify corresponding grain sizes across the SER section and extract Johnson-Cook model constants for computational optimization. Knowing that micro-grained Mg alloys obey the Hall-Petch relationship, the simulations could be used to predict and optimize grain refinement and uniformity by adjusting SER process parameters numerically. The computational results indicate that SER can reduce the grain sizes of AZ31B by up to 42% relative to conventional rolling of equivalent reduction ratio, in addition to the corresponding non-uniformity value of 0.0914. Also, results revealed that the contact length (L) between the rolled section and the traditional rollers correlates strongly with grain refinement and uniformity. L is directly relatable to the controllable process parameters of TL, the coefficient of friction (µ), and the roller radius (Rr). Our multi-objective optimization suggests increasing (L) to its maximum practical value to obtain the best grain refinement and uniformity with SER. Limitations of SER are also discussed.

A dual-mode novel Parabolic Trough Collector for process heating applications in small scale industries—Thermo-hydraulic and performance investigation

Only a few industries worldwide use solar heat for industrial processes, despite the fact that it is a proven and cleaner solution. More over, Small-scale industries need hot water and low-enthalpy steam, but such systems receive scant attention due to the active nature of Parabolic Trough Collectors as well as the use of less efficient flat plate technology in this temperature range. This delineate the opportunity for research focus in efficient passive technologies especially in low temperature range. In this regard a novel dual mode Parabolic Trough Collector based on an Open Natural Circulation Loop (PTC-ONCL) is proposed here. Focus of this work is to assess the proposed system’s suitability for process heating applications requiring hot water/low enthalpy steam, especially in rural areas. Experiments are conducted on an in-house prototype. A novel methodology for correlating actual solar data to the input heat load for the in-house test facility is developed. Five representative solar days are considered for individual tests. Startup, transient, and efficiency parameters are evaluated. Productivity, industrial viability, and environmental impact are also accessed. Throughout the test, the loop maintained a stable flow, where the start-up oscillations, thermal oscillations and type-I instabilities are observed. The system operates at an unprecedented efficiency of 72 ± 4% in hot water mode and 70 ± 5% in Steam generation over a 7 h period. The economic analysis shows an ambitious Levelized Cost of Heat of 2.8 cents/kWh, with a payback period of 3.21 years. Moreover environmental study shows its huge potential in reducing the CO 2 emissions. A dimensionless index is proposed to represent the solar day and is correlated to predict the average water temperature and steam generated with RMSE values of 0.98 °C and 0.125 kg respectively. The solar day index comprehends the total irradiation, wind velocity and the ambient temperature. The proposed PTC-ONCL system is capable of producing an annual average of 8.67 kgday −1 and/or 150 L of hot water at an average temperature of 89.07 °C. The results, and the system’s low cost and near-maintenance-free nature demonstrates its capability in the desired application, both technologically and economically. • A passive Parabolic Trough Collector based on an Open Natural Circulation Loop for process heat at low temperature. • New methodology correlates actual solar data to input for an in-house test facility. • Generates 8.67 kg of steam/ hot water at 89 °C on a yearly average with 65% efficiency. • Levelized Cost of Heat of 2.8 cent/kWh & 3.2 years of payback period found promising. • Dimensionless solar day index includes combines irradiation and ambient condition.

Cladding-Pumped Er/Yb-Co-Doped Fiber Amplifier for Multi-Channel Operation

Cladding-pumped erbium (Er3+)/ytterbium (Yb3+)-co-doped fiber amplifiers are more advantageous at high output powers. However, this amplification technique also has potential in telecom-related applications. These types of amplifiers have complex properties, especially when considering gain profile and a pump conversion efficiency. Such metrics depend on the doped fiber profile, absorption/emission spectra, and the input signal power. In this context, we design, build and characterize an inhouse prototype of cladding-pumped Er3+/Yb3+-co-doped fiber amplifier (EYDFA). Our goal is to identify the EYDFA configuration (a co-doped fiber length, pump power, input signal power) suitable for signal amplification in a multichannel fiber-optic transmission system with a dense wavelength allocation across the C-band (1530–1565 nm). Our approach involves experimentally determining the Er3+/Yb3+-co-doped fiber’s parameters to be used in a simulation setup to decide on an initial EYDFA configuration before moving to a laboratory setup. An experimental EYDFA prototype is tested under different conditions using a 48-channel dense wavelength division multiplexing (DWDM, 100 GHz) system to evaluate the absolute gain and gain uniformity. The obtained results allow the cladding pump amplifier’s suitability for wideband signal amplification to be assessed. The developed prototype provides >21 dB of gain with a 12 dB ripple within 1534–1565 nm. Furthermore, we show that the gain profile can be partially flattened out by using longer EYDF spans. This enhances signal amplification in the upper C-band in exchange for a weaker amplification in the lower C-band, which can be marginally improved with higher pump powers.

Cassette-like peeling system for testing the adhesion of soft-to-rigid assemblies

A novel cassette-like peeling system is developed to address the limitations of current peeling standards when evaluating bonding quality of soft-to-rigid assemblies. The system transforms the translation of a specimen in the conventional peeling configuration to rotation via a cassette-like spool clamping the specimen. The peeled film is loaded by tension to drive the winding of the spool, thus achieving self-similar crack propagation and a stationary peeling front unrelated to the stiffness of the film. These features enable the system’s compatibility with most universal testers and in situ observation of crack tip morphology with optical instruments. Analysis to derive the intrinsic fracture energy when peeling a soft film is conducted based on Griffith energy balance, making use of which, a parametric study is performed to clarify the related mechanisms. We carry out a comprehensive validation of the cassette-like peeling system by performing a series of peeling tests using our in-house prototype and by comparing the results with those from the conventional system. Owing to its universality and ease-of-use, the proposed cassette-like peeling system can potentially be applied to the development of the next generation of peel test standards.

3D Surveying of Underground Built Heritage: Opportunities and Challenges of Mobile Technologies

Among the existing Cultural Heritage settings, Underground Built Heritage (UBH) represents a peculiar case. The scarce or lack of knowledge and documentation of these spaces frequently limits their proper management, exploitation, and valorization. When mapping these environments for documentation purposes, the primary need is to achieve a complete, reliable, and adequate representation of the built spaces and their geometry. Terrestrial laser scanners were widely employed for this task, although the procedure is generally time-consuming and often lacks color information. Mobile Mapping Systems (MMSs) are nowadays fascinating and promising technologies for mapping underground structures, speeding up acquisition times. In this paper, mapping experiences (with two commercial tools and an in-house prototype) in UBH settings are presented, testing the different handheld mobile solutions to guarantee an accurate and reliable 3D digitization. Tests were performed in the selected case study of Camerano Caves (Italy), characterized by volumetric complexity, poor lighting conditions, and difficult accessibility. The aim of this research activity is not only to show the differences in the technological instruments used for 3D surveying, but rather to argue over the pros and cons of the systems, providing the community with best practices and rules for 3D data collection with handheld mobile systems. The experiments deliver promising results when compared with TLS data.

RLEP LAMP for the laboratory confirmation of leprosy: towards a point-of-care test

BackgroundNucleic acid-based amplification tests (NAAT), above all (q)PCR, have been applied for the detection of Mycobacterium leprae in leprosy cases and household contacts with subclinical infection. However, their application in the field poses a range of technical challenges. Loop-mediated isothermal amplification (LAMP), as a promising point-of-care NAAT does not require sophisticated laboratory equipment, is easy to perform, and is applicable for decentralized diagnosis at the primary health care level. Among a range of gene targets, the M. leprae specific repetitive element RLEP is regarded as highly sensitive and specific for diagnostic applications. MethodsOur group developed and validated a dry-reagent-based (DRB) RLEP LAMP, provided product specifications for customization of a ready-to-use kit (intended for commercial production) and compared it against the in-house prototype. The assays were optimized for application on a Genie® III portable fluorometer. For technical validation, 40 “must not detect RLEP” samples derived from RLEP qPCR negative exposed and non-exposed individuals, as well as from patients with other conditions and a set of closely related mycobacterial cultures, were tested together with 25 “must detect RLEP” samples derived from qPCR confirmed leprosy patients. For clinical validation, 150 RLEP qPCR tested samples were analyzed, consisting of the following categories: high-positive samples of multibacillary (MB) leprosy patients (> 10.000 bacilli/extract), medium-positive samples of MB leprosy patients (1.001–10.000 bacilli/extract), low-positive samples of MB leprosy patients (1–1.000 bacilli/extract), endemic controls and healthy non-exposed controls; each n = 30. ResultsTechnical validation: both LAMP formats had a limit of detection of 1.000 RLEP copies, i.e. 43–27 bacilli, a sensitivity of 92% (in-house protocol)/100% (ready-to-use protocol) and a specificity of 100%. Reagents were stable for at least 1 year at 22 °C. Clinical validation: Both formats showed a negativity rate of 100% and a positivity rate of 100% for high-positive samples and 93–100% for medium positive samples, together with a positive predictive value of 100% and semi-quantitative results. The positivity rate for low-positive samples was 77% (in-house protocol)/43% (ready-to-use protocol) and differed significantly between both formats. ConclusionsThe ready-to-use RLEP DRB LAMP assay constitutes an ASSURED test ready for field-based evaluation trials aiming for routine diagnosis of leprosy at the primary health care level.

Absolute multilateration-based coordinate measurement system using retroreflecting glass spheres

We have measured the three-dimensional coordinates of retroreflecting glass spheres using a multilateration technique. To this end, the distances between each target and our measurement heads have been determined by an in-house prototype of electro-optical absolute distance meter. The used targets are spheres of glass refractive index n = 2 and of diameter 14.2 mm. They offer a much larger aperture than corner cubes and a lower cost, but they present a low reflectivity. However, this paper shows that with a proper collimation of the laser beams it is possible to reach a range of operation of 20 m. The standard uncertainty on such distances is better than 11 μm, including the mechanical errors of the gimbal mechanisms of our aiming systems. This uncertainty has been validated thanks to a comparison with an interferometric bench. In addition, the measurement of the coordinates of 16 glass spheres using a self-calibration multilateration algorithm has also confirmed the performances of the developed system: the standard deviation on the position errors has been estimated to about 10 μm.

Noninvasive Point-of-Care Nanobiosensing of Cervical Cancer as an Auxiliary to Pap-Smear Test.

A potential cancer antigen (Ag), protein-phosphatase-1-gamma-2 (PP1γ2), with a restricted expression in testis and sperms has been identified as a biomarker specific to cervical cancer (CaCx). Detection of this cancer biomarker antigen (NCB-Ag) in human urine opens up the possibility of noninvasive detection of CaCx to supplement the dreaded and invasive Pap-smear test. A colorimetric response of an assembly of gold nanoparticles (Au NPs) has been employed for the quantitative, noninvasive, and point-of-care-testing of CaCx in the urine. In order to fabricate the immunosensor, Au NPs of sizes ∼5-20 nm have been chemically modified with a linker, 3,3'-di-thio-di-propionic-acid-di(n-hydroxy-succinimide-ester) (DTSP) to attach the antibody (Ab) specific to the NCB-Ag. Interestingly, the addition of Ag to the composite of Ab-DTSP-Au NPs leads to a significant hypsochromic shift due to a localized surface plasmon resonance phenomenon, which originates from the specific epitope-paratope interaction between the NCB-Ag and Ab-DTSP-Au NPs. The variations in the absorbance and wavelength shift during such attachments of different concentrations of NCB-Ag on the Ab-DTSP-Au NPs composite have been employed as a calibration to identify NCB-Ag in human urine. An in-house prototype has been assembled by integrating a light-emitting diode of a narrow range wavelength in one side of a cuvette in which the reaction has been performed while a sensitive photodetector to the other side to transduce the transmitted signal associated with the loading of NCB-Ag in the Ab-DTSP-Au NPs composite. The proposed immunosensing platform has been tested against other standard proteins to ensure noninterference alongside proving the proof-for-specificity of the NCB detection.

Solar power sail membrane prototype for OKEANOS mission

This paper reports on the manufacturing and evaluation of a solar power sail membrane prototype for the OKEANOS project. The in-house prototype was built by the Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency. Mechanical and electrical evaluation tests were conducted. The membrane, thin-film solar cells, reflectivity control devices were good condition after the manufacturing and handling. The improvements in the manufacturing process and design were found. The manufacturing process and design were fundamentally established. After the prototype, improvement plans for the manufacturing process and design were tried. We have a prospect of manufacturing the flight model sail and continue to the development.

Blockchain Radio Access Network Beyond 5G

We present a blockchain radio access network (B-RAN) as an advanced wireless access paradigm. The proposed B-RAN unites massive trustless subnetworks to form a large-scale trustworthy cooperative network by leveraging the blockchain principle. We introduce the economic concept of network effects with respect to the benefit of a growing B-RAN. We show that B-RAN can create and capture values by connecting multilateral groups and constructing a multi-sided platform (MSP). To establish multi-fold trust among distinct groups for deep integrations and healthy interactions, we divide functions of B-RAN into six layers within a hierarchical architecture to build trust from the ground up, and provide a number of key enabling technologies to overcome major obstacles in B-RAN. More importantly, we assess the performance of B-RAN using our unique in-house prototype through three representative case studies.

OSL using a prototype fibre-mounted sensor and automated reader assembly

Application-viable yields of optically stimulated luminescence (OSL) are known to be provided by a number of materials, Al2O3:C nanoDot OSLDs being one of those currently favoured, dominating the world of commercial passive radiation dosimetry. Associated with the use of such materials is the need for versatile, high performance readout devices, opportunities remaining for novel developments in support of the OSL media, as emphasised herein. Present study focuses on the data acquisition capability of an in-house prototype OSL reader, luminescence stimulation being provided by a 30 mW green LED light (spectral mid-point ~ 515 nm). In providing for the additional versatility of making stand-off (at a distance) measurements, the dosimeter sensors (nanoDot OSLD chips) were attached to a polymethyl-methcrylate (PMMA) fibre cable, allowing characterization of the OSL (phosphorescence) at very low risk. Using this prototype instrument, key OSL features from an Al2O3:C sensor medium have been captured, excellent quantitative agreement being found between present results and those of others using other readers. One further feature of the current design is that it also allows investigation of the excitation light wavelength dependence of sensor media that could be competitive to Al2O3:C, there being the additional ability to swap out the OSL sensor, filters and other support components.

Динамическая верификация контроллеров шин систем-на-кристалле

The paper presents an approach to verification of commutation components of Systems-on-Chip. The core idea is to verify bus controllers and supporting interface parts connected to a reference model at unit-level. The reference model in the approach is suggested to be written in SystemC so that to be easily adjusted to the required bus parameters. The in-house prototype implementing the approach has been applied to the verification of a Verilog model of Wishbone controller. There is a possibility to extend the approach to support other busses and protocols by development of the interface library.

GeroMAG: In-House Prototype of an Innovative Sealed, Compact and Non-Shaft-Driven Gerotor Pump with Magnetically-Driving Outer Rotor

The technology of gerotor pumps is progressing towards cutting-edge applications in emerging sectors, which are more demanding for pump performance. Moreover, recent environmental standards are heading towards leakage-free and noiseless hydraulic systems. Hence, in order to respond to these demands, this study, which will be referred to as the GeroMAG concept, aims to make a leap from the standard gerotor pump technology: a sealed, compact, non-shaft-driven gerotor pump with a magnetically-driving outer rotor. The GeroMAG pump is conceived as a variable-flow pump to accomplish a standard volumetric flow rate at low rotational speed with satisfactory volumetric efficiency. By following the authors’ methodology based on a catalogue of best-practice rules, a custom trochoidal gear set is designed. Then, two main technological challenges are encountered: how to generate the rotational movement of the driving outer rotor and how to produce the guide of rotation of the gear set once there is no drive shaft. To confront them, a quiet magnet brushless motor powers the driving outer rotor through pole pieces placed in its external sideway and the rotational movement is guided by the inner edgewise pads carved on it. Subsequently, GeroMAG pump architecture, prototype, housing, methodology, materials and manufacture will be presented. As a principal conclusion, the GeroMAG proof of concept and pump prototype are feasible, which is corroborated by experimental results and performance indexes.

An Integrated Nanotechnology-Enabled Transbronchial Image-Guided Intervention Strategy for Peripheral Lung Cancer.

Early detection and efficient treatment modality of early-stage peripheral lung cancer is essential. Current nonsurgical treatments for peripheral lung cancer show critical limitations associated with various complications, requiring alternative minimally invasive therapeutics. Porphysome nanoparticle-enabled fluorescence-guided transbronchial photothermal therapy (PTT) of peripheral lung cancer was developed and demonstrated in preclinical animal models. Systemically administered porphysomes accumulated in lung tumors with significantly enhanced disease-to-normal tissue contrast, as confirmed in three subtypes of orthotopic human lung cancer xenografts (A549, H460, and H520) in mice and in an orthotopic VX2 tumor in rabbits. An in-house prototype fluorescence bronchoscope demonstrated the capability of porphysomes for in vivo imaging of lung tumors in the mucosal/submucosal layers, providing real-time fluorescence guidance for transbronchial PTT. Porphysomes also enhanced the efficacy of transbronchial PTT significantly and resulted in selective and efficient tumor tissue ablation in the rabbit model. A clinically used cylindrical diffuser fiber successfully achieved tumor-specific thermal ablation, showing promising evidence for the clinical translation of this novel platform to impact upon nonsurgical treatment of early-stage peripheral lung cancer. Cancer Res; 76(19); 5870-80. ©2016 AACR.

Computational modeling of alkaline air-breathing microfluidic fuel cells with an array of cylinder anodes

A three-dimensional computational model is developed for an alkaline air-breathing microfluidic fuel cell (AMFC) with an array of cylinder anodes. The model is validated against experimental data from an in-house prototype AMFC. The distributions of fluid velocity, fuel concentration and current density of the fuel cell are analyzed in detail. The effect of reactant flow rate on the cell performance and electrode potentials is also studied. The model results suggest that fuel crossover is minimized by the fast electrolyte flow in the vicinity of the cathode. The current production of each anode is uneven and is well correlated with internal ohmic resistance. Fuel transfer limitation occurs at low flow rates (<100 μL min−1) but diminishes at high flow rates. The model results also indicate that cathode potential reversal takes place at combined low flow rate and high current density conditions, mainly due to the improved overpotential downstream where fuel starvation occurs. The anode reaction current distribution is found to be relatively uniform, which is a result of a compensating mechanism that improves the current production of the bottom anodes downstream.

Computer-aided assessment of hepatic contour abnormalities as an imaging biomarker for the prediction of hepatocellular carcinoma development in patients with chronic hepatitis C

PurposeTo evaluate whether a hepatic fibrosis index (HFI), quantified on the basis of hepatic contour abnormality, is a risk factor for the development of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C. Materials and methodsOur institutional review board approved this retrospective study and written informed consent was waved. During a 14-month period, consecutive 98 patients with chronic hepatitis C who had no medical history of HCC treatment (56 men and 42 women; mean age, 70.7 years; range, 48–91 years) were included in this study. Gadoxetic acid-enhanced hepatocyte specific phase was used to detect and analyze hepatic contour abnormality. Hepatic contour abnormality was quantified and converted to HFI using in-house proto-type software. We compared HFI between patients with (n=54) and without HCC (n=44). Serum levels of albumin, total bilirubin, aspartate transferase, alanine transferase, percent prothrombin time, platelet count, alpha-fetoprotein, protein induced by vitamin K absence-II, and HFI were tested as possible risk factors for the development of HCC by determining the odds ratio with logistic regression analysis. ResultsHFIs were significantly higher in patients with HCC (0.58±0.86) than those without (0.36±0.11) (P<0.001). Logistic analysis revealed that only HFI was a significant risk factor for HCC development with an odds ratio (95% confidence interval) of 26.4 (9.0–77.8) using a cutoff value of 0.395. ConclusionThe hepatic fibrosis index, generated using a computer-aided assessment of hepatic contour abnormality, may be a useful imaging biomarker for the prediction of HCC development in patients with chronic hepatitis C.

Next Generation 3D Display Applications using Laser Scanning Pico Projectors

This thesis presents four novel 3D display methods and a number of new applications using commercial laser scanning pico projectors that have been developed with major contributions from our laboratory during the last decade. The new methods developed in this thesis are (i) mixed-polarization stereoscopic display using single-projector and passive polarized glasses, (ii) a new type of glasses that can relieve the accommodation and vergence conflict associated with all the stereoscopic displays, (iii) rotating screen based auto-stereoscopic display for a single-viewer using two pico-projectors, and (iv) multi-user multi-view auto-stereoscopic display using an array of pico-projectors. Furthermore, a head-mounted pico-projector is also demonstrated as a new augmented- reality application aimed at motion-capture actors. The first method introduces a new twist on glasses based stereoscopic projection displays as it utilizes polarization and color multiplexing simultaneously and avoids weaknesses associated with previous methods. This new method is named Mixed Polarization 3D. Color imbalance artifacts associated with anaglyph glasses are avoided by alternating the colors presented to each eye. In mixed polarization 3D, flicker is not observed even at 60 Hz since both eyes receive at least one color frame in every single frame. The second method, named Super Stereoscopic 3D Display (SS3D), introduces a major improvement on stereoscopic 3D displays for avoiding accommodation-vergence conflict. Our method provides at least two views to a single eye by using special apertures equipped with selective filters in front of the users’ eye. Our designs can be embedded into conventional stereoscopic glasses or can be developed as special contact lenses. The third method introduces a single viewer multi-view autostereoscopic projection display, which is invented in our laboratory by a co-worker. The technique uses two mobile projectors, a rotating retro-reflective diffuser screen, and a head-tracking camera. As two dynamic viewing slits are created at the viewers position, the slits can track the position of the eyes by rotating the screen. The last method introduces a new modular multi-user multi-view autostereoscopic display architecture based on an array of pico-projectors and a vertical diffuser screen. A single projector provides a portion of the each perspective observed through the vertical diffuser. Unlike similar projector-array based displays, the screen assembly complexity and the size of the projection display hardware have been decreased dramatically. Our proposal has the capability to provide horizontal expansion in the screen size, and an increase in the number of different perspectives as well. Lastly, an augmented reality (AR) system is proposed and developed for supporting motion capture actors. This system allows seeing and exploring the digital environment without occluding the actors visual field. An in-house prototype is built by combining a retro-reflective screen that covers the walls and a headband consisting of a laser scanning projector with a smartphone. Built-in sensors on the smartphone provide navigation capabilities in the digital world.