gebhart/patrepeval huggingface dataset:
Estimating voxel volume fractions of trabecular bone on the basis of magnetic resonance images acquiredin vivo (1999)

A method is described for extracting information from images acquired in the limited spatial resolution regime in which the structures to be identified are smaller than the image voxel size. Under these conditions and in the presence of noise, the voxel intensity histogram is monomodal; therefore, segmenting the image with an intensity threshold is inaccurate. The present method, which is applicable to two-phase materials of discrete intensity, relies on iterative deconvolution to obtain a noiseless histogram. A noiseless image is then generated on the basis of the noiseless histogram and the unprocessed image. In the current work, the method is referred to as bone volume fraction (BVF) mapping, since it has been applied to determine the spatial distribution of trabecular bone. BVF computed from maps generated on the basis of in vivo magnetic resonance images of the human radius has been shown to compare well with bone mineral density (R2 = 0.8). The accuracy and precision of BVF measurements have been further evaluated by using a BVF map of the radius as a gold standard and then adding different levels of noise to generate test images. The results suggest that the error in BVF is <0.01 for SNR > 8. © 1999 John Wiley & Sons, Inc. Int J Imaging Syst Technol, 10, 186–198, 1999
<title>Active materials for integrated optic applications</title> (1999)

The ability to engineer glass properties through the selection and adjustment of chemical composition continues to make glass a leading material in both active and passive applications. The development of optimal glass compositions for integrated optical applications requires a number of considerations that are often at variance with one another. Of critical importance is that the glass offers compatibility with standard ion exchange technologies, allowing fabrication of guided wave structures. In addition, for application as an active material, the resultant structures must be characterized by absence of inclusions and low absorption at the lasing wavelength, putting demands on both the selection and identity of the raw materials used to prepare the glass. We report on the development of an optimized glass composition for integrated optic applications that combines good laser properties with good chemical durability allowing for a wide range of chemical processing steps to be employed without substrate deterioration. In addition, care was taken during the development of this glass to insure that the selected composition was consistent with manufacturing technology for producing high optical quality glass. We present the properties of the resultant glasses, including results of detailed chemical and laser properties, for use in the design and modeling of active waveguides prepared with these glasses.
Electron leakage and its suppression via deep-well structures in 4.5- to 5.0-μm-emitting quantum cascade lasers (2010)

The equations for threshold-current density Jth and external differential quantum efficiency d of quantum cascade lasers (QCLs) are modified to include electron leakage and the electron-backfilling term corrected to take into account hot electrons in the injector. We show that by introducing both deep quantum wells and tall barriers in the active regions of 4.8-µm-emitting QCLs, and by tapering the conduction-band edge of both injector and extractor regions, one can significantly reduce electron leakage. The characteristic temperatures for Jth and d, denoted by T0 and T1, respectively, are found to reach values as high as 278 and 285 K over the 20 to 90°C temperature range, which means that Jth and d display 2.3 slower variation than conventional 4.5- to 5.0-µm-emitting, high-performance QCLs over the same temperature range. A model for the thermal excitation of hot injected electrons from the upper laser level to the upper active-region energy states, wherefrom some relax to the lower active-region states and some are scattered to the upper miniband, is used to estimate the leakage current. Estimated T0 values are in good agreement with experiment for both conventional QCLs and deep-well QCLs. The T1 values are justified by increases in both electron leakage and waveguide loss with temperature
Wavelength Selective Crossconnects (2013)

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text N. K. Fontaine, R. Ryf, and D. T. Neilson, "Wavelength Selective Crossconnects," in 2013 18th OptoElectronics and Communications Conference held jointly with 2013 International Conference on Photonics in Switching, (Optica Publishing Group, 2013), paper ThT1_4. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article
Arithmetic circuit design with memristor based high fan-out logic gates (2016)

The application of memristors in logic operations have recently gained importance and are being investigated. The work presented in this paper describes a new low power technique of using memristors to perform arithmetic operations like addition and multiplication. It focuses on reducing the hardware costs and associated design complexity. The idea of “logic implication” is combined with an analog technique of using current mirrors to perform logic operations. By using current mirrors, the problem of limited fan-out of logic implication can be overcome, enabling more parallel operations to run together. The delay for even an XOR operation can be reduced to 1 cycle, compared to the 5 cycles taken by logic implication. The design of a full adder, ripple carry adder and array multiplier are described. Metrics of area and latency are compared to previous works.
Prediction of Oxygen Storage Capacity and Stored NOx by HEGO Sensors for Improved LNT Control Strategies (2002)

In the absence of on-line emission measurements, the control of lean burn engine aftertreatment system must be implemented by using models of feedgas emissions and the aftertreatment subsystems, together with measured variables such as mass air flow rate, feedgas and tailpipe relative air-to-fuel ratios, etc. In particular, accurate estimation of stored oxygen and NOx in the LNT is of critical importance. When the ambient conditions (such as humidity, LNT brick temperature, and sulfur poisoning) change or the engine components age, oxygen storage capacity and NOx amount in the LNT vary significantly, and the performance of the control system that relies on these variables may deteriorate if the accuracy of the estimate deteriorates with the change in hardware. In this paper, we show that voltage trajectories of a tailpipe HEGO sensor can provide sufficient information to predict oxygen capacity during storage phase and stored NOx during purge phase of an lean NOx trap (LNT). This result can be used to provide accurate prediction of the termination time of purge operation, leading to improved control strategies for LNT operation. This finding also indicates that more expensive UEGO sensors can be avoided without tangible performance penalty on LNT control.
Semantically-Smart Disk Systems (2003)

Rights to individual papers remain with the author or the author&apos;s employer. Permission is granted for noncommercial reproduction of the work for educational or research purposes. This copyright notice must be included in the reproduced paper. USENIX acknowledges all trademarks herein.
Enantioselective Iridium-Catalyzed Allylic Alkylation Reactions of Masked Acyl Cyanide Equivalents (2017)

The first enantioselective iridium-catalyzed allylic alkylation reaction of a masked acyl cyanide (MAC) reagent has been developed. The transformation allows for the use of an umpoled synthon, which serves as a carbon monoxide equivalent. The reaction proceeds with good yield and excellent selectivity up to gram scale for a wide range of substituted allylic electrophiles, delivering products amenable to the synthesis of highly desirable, enantioenriched vinylated α-aryl carbonyl derivatives.
Swing-Free Cranes via Input Shaping of Operator Commands (1999)

This paper presents an open-loop control method for suppressing payload oscillation or swing caused by operator commanded maneuvers in rotary boom cranes and the method is experimentally verified on a one-sixteenth scale model of a Haggluncls shipboard crane. The crane configuration consists of a payload mass that swings like a spherical pendulum on the end of a lift-line which is attached to a boom capable of hub rotation (slewing) and elevation (luffing). Positioning of the payload is accomplished through the hub and boom angles and the load-line length. Since the configuration of the crane affects the excitation and response of the payload, the swing control scheme must account for the varying geometry of the system. Adaptive forward path command filters are employed to remove components of the command signal which induce payload swing. moving supplies ashore in the absence of port facilities. The keystone of the system will be boom cranes mounted on a dedicated ship, which will move cargo from container ships to lighterages, small landing craft, for transport to shore. See Figure
Strength of Perpendicular Magnetic Anisotropy at Bottom and Top Interfaces in [Pt/Co/Pt] Trilayers (2014)

The individual strengths of perpendicular magnetic anisotropy (PMA) at the bottom and top interfaces in sputtered [Pt/Co/Pt] trilayers are determined. The PMA strength from the top Co/Pt interface is significantly weaker than that from the bottom Pt/Co interface, indicating a similar difference in the interface quality. The contribution to the total anisotropy strength from the top Co/Pt interface increases with decreasing top Pt layer thickness; for a stack of Co thickness 1 nm, the contribution is only 10% for a top Pt layer of thickness 3.0 nm, but it increases to 32% for a Pt layer of thickness 0.2 nm.
Frequent Item-set Mining without Ubiquitous Items (2018)

Frequent Item-set Mining (FIM), sometimes called Market Basket Analysis (MBA) or Association Rule Learning (ARL), are Machine Learning (ML) methods for creating rules from datasets of transactions of items. Most methods identify items likely to appear together in a transaction based on the support (i.e. a minimum number of relative co-occurrence of the items) for that hypothesis. Although this is a good indicator to measure the relevance of the assumption that these items are likely to appear together, the phenomenon of very frequent items, referred to as ubiquitous items, is not addressed in most algorithms. Ubiquitous items have the same entropy as infrequent items, and not contributing significantly to the knowledge. On the other hand, they have strong effect on the performance of the algorithms and sometimes preventing the convergence of the FIM algorithms and thus the provision of meaningful results. This paper discusses the phenomenon of ubiquitous items and demonstrates how ignoring these has a dramatic effect on the computation performances but with a low and controlled effect on the significance of the results.
Cryosurgery for Breast Malignancies: Apparatus and Techniques (1999)

Abstract The treatment of breast cancer has evolved from the time of mutilation and ignorance in the middle ages, to one of breast conserving management and an intense study and understanding of the biological mechanisms driving tumor cells. As the treatment is directed to the cellular and sub-cellular level, breast conserving surgical procedures take on a more important role. Recent published results from neoadjuvant trials indicate a decrease in tumor size in 80% of patients and a modest increase in conversion from mastectomy to lumpectomy. By 2010 AD, it is estimated that 50% of all new breast cancers discovered will be less than 10 mm in diameter (Cady et al., 1996), which represents 90,000 patients. Standard surgical treatment would require an open segment resection, an operating room, anesthesia, cosmetic concerns and substantial cost. Add to this the number of patients who require segmental resection following complete clinical or pathological response following neoadjuvant chemotherapy, and the cost increases. An alternative method of tumor removal or destruction for small malignancies is needed to complete the biological assault on breast cancer. Cryosurgery may be one of these alternative means. Cryosurgery has been used successfully for more than three decades to treat benign and malignant neoplasms. To date, there is one reported case of primary breast cancer treatment with cryotherapy (Staren et al., 1997), which was followed up with ultrasound-guided biopsy, and which was found negative for malignancy 12 weeks post-cryosurgery. Cryotherapy carries many benefits in addition to the attractive concept of minimally invasive surgery. Low temperatures generate anaesthetic effect. Hemorrhage is reduced due to thrombosis of small blood vessels. Cryotherapy may cause stimulation of the body’s immune system, which additionally augments local tumor destruction and may also induce a response in metastatic tumor sites (Suzuki, 1995). With multiple treatments such as neoadjuvant therapy, hormone therapy, and radiation, which have the ability to downsize primary cancers and treat small cancers, lumpectomy may be increasingly used. Current diagnostic imaging trends are increasingly detecting small cancers (&lt; 1 cm). The minimization of surgical intervention to compliment these trends is a natural progression of technology and understanding of the biological processes involved. Our ongoing research program to evaluate cryosurgery in the breast is comprised of several phases: (i) development of a miniaturized cryoprobe and a cryodevice for minimally invasive breast cryosurgery; (ii) validation testing of the cryoprobe and device in vivo; (iii) development of a technique to evaluate the injury associated with cryotreatment of the breast; (iv) comparison of the ultrasound imaged “‘ice-ball” in vivo with the resulting cryoinjury immediately post-cryosurgery; and, (v) long-term follow-up post-cryosurgery in a recently-pregnant sheep breast model. The work to date is part of this report.
The architecture of generic VNFM using TOSCA (2017)

Network function virtualization is quickly gaining acceptance as the new approach to delivering communication services. The promises of greater flexibility and dramatically reduced time to introduce new services coupled with the cost advantages, are driving communications service providers(CSP) around the world to begin deploying NFV-based services. An NFV operation system is divided into the NFV Orchestrator (NFVo), VNF Manager (VNFM), and VIM (Virtual Infrastructure Manager) subsystems in accordance with the ETSI standard, and the VNFM is defined as the system provided by the VNF manufacturer. In this paper, we present a generic VNF management system for administration and operation of the NVF” under the following structure and to specify the Or-Vnfm, Ve-Vnfm and Vi-Vnfm interfaces, with the goal of developing a generic and scalable VNFM to support various VNFs.
Heterocyclic HIV-1 Protease Inhibitors (1999)

[formula: see text] A series of simple heterocyclic HIV-1 protease inhibitors were developed on the basis of size, shape, and electronic complementarity to the active site of the enzyme. The C2-symmetric heterocycles do not contain a transition-state isostere nor are they active site directed irreversible inhibitors; thus, they represent the success of a new design strategy. The first generation heterocycles inhibit the protease in the micromolar range, whereas control compounds show no bioactivity at the same concentrations.
Conservation and Diversity in the Primary Forward Photodynamics of Red/Green Cyanobacteriochromes (2014)

Phytochromes are red/far-red photosensory proteins that detect the ratio of red to far-red light. Crucial to light regulation of plant developmental biology, phytochromes are also found in fungi, bacteria, and eukaryotic algae. In addition to phytochromes, cyanobacteria also can contain distantly related cyanobacteriochromes (CBCRs) that, like phytochromes, utilize the photoisomerization of a linear tetrapyrrole (bilin) chromophore to convert between two photostates with distinct spectral properties. CBCRs exhibit a wide range of photostates spanning the visible and even near-ultraviolet spectrum. In both phytochromes and CBCRs, biosynthesis initially yields a holoprotein with bilin in the 15Z configuration, and the 15E photoproduct can often revert to the 15Z photostate in the absence of light (dark reversion). One CBCR subfamily, red/green CBCRs, typically exhibits red-absorbing dark states and green-absorbing photoproducts. Dark reversion is extremely variable in red/green CBCRs with known examples ranging from seconds to days. One red/green CBCR, NpR6012g4 from Nostoc punctiforme, is also known to exhibit forward photoconversion that has an unusually high quantum yield at ∼40% compared to 10-20% for phytochromes and CBCRs from other subfamilies. In the current study, we use time-resolved pump-probe absorption spectroscopy with broadband detection and multicomponent global analysis to characterize forward photoconversion of seven additional red/green CBCRs from N. punctiforme on an ultrafast time scale. Our results reveal that red/green CBCRs exhibit a conserved pathway for primary forward photoconversion but that considerable diversity exists in their excited-state lifetimes, photochemical quantum yields, and primary photoproduct stabilities.
Signed graph based approach for on-line optimization in cognitive networks (2011)

One of the major architectural components shared between cognitive radios and networks is a cognitive engine supporting a cognitive process. Many of the decision making will need an optimization core for determining the optimum assignment for the control variables. This needs to be on-line to take care of the dynamics of the network and user contexts with strict time budgets. Moreover the overall network system is highly non-linear and often the state relations are analytically not tractable. An efficient search algorithm using a system model incorporating aspects of system ontology is be of value. Here a signed graph based methodology is proposed to incorporate the knowledge of influence relationship between state variables to guide a heuristic optimization process. The proposed methodology is illustrated using a typical wireless link optimization problem.
C2′-OH of Amphotericin B Plays an Important Role in Binding the Primary Sterol of Human Cells but Not Yeast Cells (2013)

Amphotericin B (AmB) is a clinically vital antimycotic but is limited by its severe toxicity. Binding ergosterol, independent of channel formation, is the primary mechanism by which AmB kills yeast, and binding cholesterol may primarily account for toxicity to human cells. The leading structural model predicts that the C2' hydroxyl group on the mycosamine appendage is critical for binding both sterols. To test this, the C2'-OH was synthetically deleted, and the sterol binding capacity of the resulting derivative, C2'deOAmB, was directly characterized via isothermal titration calorimetry. Surprisingly, C2'deOAmB binds ergosterol and, within the limits of detection of this experiment, does not bind cholesterol. Moreover, C2'deOAmB is nearly equipotent to AmB against yeast but, within the limits of detection of our assays, is nontoxic to human cells in vitro. Thus, the leading structural model for AmB/sterol binding interactions is incorrect, and C2'deOAmB is an exceptionally promising new antifungal agent.
Semiconductor photonic integrated circuits (1990)

Photonic integrated circuits (PICs) are that subset of optoelectronic integrated circuits (OEICs) that focus primarily on the integration of interconnected guided-wave optical devices. A good example of a simple but potentially important PIC is the butt-coupled integration of a distributed feedback (DFB) laser with an electroabsorption modulator to provide a low-chirp high-speed modulated source. 1 Many researchers have also pointed out that three-section continuously tunable distributed Bragg reflector (DBR) lasers are also PICs, with an integrated multielement resonator composed of a separately controlled gain medium, phase shifter, and tunable Bragg mirror. 2-4
Small-dimension power-efficient high-speed vertical-cavity surface-emitting lasers (2007)

Small-dimension power-efficient high-speed oxide-confined 980 nm vertical-cavity surface-emitting lasers (VCSELs) with record-high bandwidth/power-dissipation ratio of 12.5 GHz/mW have been demonstrated. The devices show a modulation bandwidth of 15 GHz at a bias current 0.9 mA, corresponding to only 1.2 mW power dissipation.
MMSE equalizers for DMT systems with and without crosstalk (2002)

This paper deals with finding optimal equalizers in the presence of intersymbol interference (ISI) and colored noise for systems using DMT (discrete multitone) modulation. Previously proposed, frequency-domain training of the equalizer performs better than its time-domain counterpart. However, frequency-domain training does not include the effects of noise. Therefore the trained equalizer minimizes only the ISI and not the overall mean square error. So far, no non-iterative method for computing the optimal equalizer exists. We find a way of computing the optimal equalizer that maximizes the SNR in the presence of ISI and colored noise. We also show how the effect of the noise can be incorporated into the training algorithm. Finally, we show that significant performance gains can be achieved using these new techniques.
SNR performance of an adaptive sigma delta modulator (2002)

In a previous study, we proposed an adaptive sigma delta modulator with an improved dynamic range. The modulator adapts the step size of the quantizer from estimates of the quantizer input instead of the modulator input. In this study, we conduct an error variance analysis of the new modulator and derive expression for the SNR. The derived expression shows that the SNR is independent of the input signal strength, which supports the simulation results.
Full-Color Self-processing Holographic Photopolymers with High Sensitivity in Red-The First Class of Instant Holographic Photopolymers (2009)

The new holographic photopolymers described herein are based on a cross-linked matrix in which the holographic grating is formed by photopolymerization of guest monomers in an interference pattern of the recording light. Diffusion of monomer, triggered by this photopolymerization, from the dark to the bright fringes of the interference pattern is the key parameter for creating high modulation in refractive index δn during hologram recording. This leads to bright visual volume holograms with high diffraction efficiency. The holographic photopolymers are self-processing, after recording the hologram only (incoherent) light exposure is necessary to bleach the final product and fix the hologram. The full color photopolymers show exceptionally high sensitivity for red laser light (633 nm).
An Efficient Intranet Networking Solution for Airborne Networks (2006)

We illustrate a novel wireless intranet networking protocol providing the flexibility and efficiency needed to operate in airborne environments. A critical component of this protocol is an efficient mobile ad-hoc networking (MANET) design, known as adaptive hybrid domain routing (AHDR) protocol, devised primarily for airborne networking. We describe the driving networking requirements and tradeoffs, protocol architecture, and measured and simulated performance. The MANET element in this protocol is composed of a strategic combination of proactive and reactive algorithms. It provides updated route information for neighbor nodes and offers optimized route resolution for unknown routes in a fast-changing topology. The set of optimization parameters for making routing decisions is configurable via a network management module. The selection of the best route, data rate, transmission power, message format, frame length, and transmission time is distributed and depends on real-time optimization parameters