cssi/SciSciGPT-SciSciNet huggingface dataset:
Cross-layer designs in coded wireless fading networks with multicast

A cross-layer design along with an optimal resource allocation framework is formulated for wireless fading networks, where the nodes are allowed to perform network coding. The aim is to jointly optimize end-to-end transport-layer rates, network code design variables, broadcast link flows, link capacities, average power consumption, and short-term power allocation policies. As in the routing paradigm where nodes simply forward packets, the cross-layer optimization problem with network coding is nonconvex in general. It is proved, however, that with network coding, dual decomposition for multicast is optimal so long as the fading at each wireless link is a continuous random variable. This lends itself to provably convergent subgradient algorithms, which not only admit a layered-architecture interpretation, but also optimally integrate network coding in the protocol stack. The dual algorithm is also paired with a scheme that yields near-optimal network design variables, namely multicast end-to-end rates, network code design quantities, flows over the broadcast links, link capacities, and average power consumption. Finally, an asynchronous subgradient method is developed, whereby the dual updates at the physical layer can be affordably performed with a certain delay with respect to the resource allocation tasks in upper layers. This attractive feature is motivated by the complexity of the physical-layer subproblem and is an adaptation of the subgradient method suitable for network control.
Can we learn algorithms from people who compute fast: An indirect analysis in the presence of fuzzy descriptions

In the past, mathematicians actively used the ability of some people to perform calculations unusually fast. With the advent of computers, there is no longer need for human calculators - even fast ones. However, recently, it was discovered that there exist, e.g., multiplication algorithms which are much faster than standard multiplication. Because of this discovery, it is possible than even faster algorithm will be discovered. It is therefore natural to ask: did fast human calculators of the past use faster algorithms - in which case we can learn from their experience - or they simply performed all operations within a standard algorithm much faster? This question is difficult to answer directly, because the fast human calculators’ self description of their algorithm is very fuzzy. In this paper, we use an indirect analysis to argue that fast human calculators most probably used the standard algorithm.
PET and PET/CT in Management of the Lymphomas

Within recent years, F-18 fluorodeoxyglucose (FDG) PET has become the most important nuclear medicine and radiology imaging modality in the management of lymphoma. FDG-PET detects more disease sites and involved organs than conventional staging procedures, including CT, and has a large influence on staging. FDG-PET performed during and after therapy seems to provide considerable prognostic information. The impact on patient outcome is not clear, however, because no controlled trials have yet been conducted and follow-up periods are generally short.
A methodology for the design and optimization of information processing systems

The design of an Information Processing System (IPS) can be divided into two major problems:1. What are the requirements of an information system, e.g., what outputs should be produced?2. What is the best way to produce the required outputs, on time, given the requirements developed in 1?
If Democracies Need Informed Voters, How Can They Thrive While Expanding Enfranchisement?

Three uncontroversial points sum to a paradox: 1) Almost every democratic theorist or democratic political actor sees an informed electorate as essential to good democratic practice. Citizens need to know who or what they are choosing and why – hence urgent calls for expansive and publicly funded education, and rights to free speech, assembly, press, and movement. 2) In most if not all democratic polities, the proportion of the population granted the suffrage has consistently expanded, and seldom contracted, over the past two centuries. Most observers, and I, agree that expanding enfranchisement makes a state more democratic. 3) Most expansions of the suffrage bring in, on average, people who are less politically informed or less broadly educated than those already eligible to vote. Putting these three uncontroversial points together leads to the conclusion that as democracies become more democratic, their decision-making processes become of lower quality in terms of cognitive processing of issues and candidate choice. The paradox is both historical – why have democracies expanded the franchise to include relatively ignorant voters? – and normative – why should democracies expand the franchise to include relatively ignorant voters? The article addresses both questions. First, I review the historical trajectory of democratization in the United States (although the argument is not specific to that country). I then describe plausible empirical explanations for the paradox: voters are not really that ignorant; the United States is not and never has been really a democracy; and institutions or electoral rules have been developed to substitute for voters’ knowledge. I also analyze plausible normative explanations for the paradox: democracy does not, or does not primarily, need cognitively sophisticated citizens; and democracy offers benefits that outweigh the deficits of citizens’ lack of knowledge. I offer a few reflections on both sets of explanations, but cannot genuinely dissolve the paradox. * Jennifer L. Hochschild is the Henry LaBarre Jayne Professor of Government at Harvard University. Many people gave useful comments; she thanks C. Anthony Broh, Katherine Levine, Sanford Levinson, David Mayhew, Cindy Rosenthal, an anonymous reviewer, the editors of Election Law Journal, and participants in seminars at the American Political Science Association’s 2009 annual convention and at the Julian J. Rothbaum Distinguished Lecture Series at the University of Oklahoma, 2007.
A main frame semiconductor memory for fourth generation computers

It has been obvious for several years that Large Scale Integration could be applied to memories. Memories offer several advantages in that a large volume of one type of device can be manufactured, and that the design can be optimized for one application. There exists a wide spectrum of memory product areas with varying size, costs, speed and enviromental performance. Most of these application areas are presently serviced by various forms of magnetic storage.
Long-Term Economic Growth and the History of Technology

Modern economic growth started in the West in the early nineteenth century. This survey discusses the precise connection between the Industrial Revolution and the beginnings of growth, and connects it to the intellectual and economic factors underlying the growth of useful knowledge. The connections between science, technology and human capital are re-examined, and the role of the eighteenth century Enlightenment in bringing about modern growth is highlighted. Specifically, the paper argues that the Enlightenment changed the agenda of scientific research and deepened the connections between theory and practice.
MTI Optimization in a Multiple-Clutter Environment

A means of optimizing a moving target indicator (MTI) filter for rejecting several types of clutter, which are generated by different mechanisms such as by rain or the ground, is formulated. lt is found that the optimal performance of such a filter depends on the spectral density functions, average radar cross sections, and the relative mean Doppler frequencies of each type of clutter. lt is shown that the optimal improvement factor of such a filter is bounded by the weighted average (weighted in accordance with the radar cross sections of the clutter types) of the improvement factor for the individual clutter type. lt is also shown that the improvement factor of such a filter is a function of the relative mean Doppler frequency f0 between the clutter types. As f0 increases, the performance of the MTI system degrades. The worst improvement factor occurs when f0 is equal to half of the radar pulse-repetition frequency (PRF).
Discrete Memoryless Interference and Broadcast Channels With Confidential Messages: Secrecy Rate Regions

We study information-theoretic security for discrete memoryless interference and broadcast channels with independent confidential messages sent to two receivers. Confidential messages are transmitted to their respective receivers while ensuring mutual information-theoretic secrecy. That is, each receiver is kept in total ignorance with respect to the message intended for the other receiver. The secrecy level is measured by the equivocation rate at the eavesdropping receiver. In this paper, we present inner and outer bounds on secrecy capacity regions for these two communication systems. The derived outer bounds have an identical mutual information expression that applies to both channel models. The difference is in the input distributions over which the expression is optimized. The inner bound rate regions are achieved by random binning techniques. For the broadcast channel, a double-binning coding scheme allows for both joint encoding and preserving of confidentiality. Furthermore, we show that, for a special case of the interference channel, referred to as the switch channel, derived bounds meet. Finally, we describe several transmission schemes for Gaussian interference channels and derive their achievable rate regions while ensuring mutual information-theoretic secrecy. An encoding scheme in which transmitters dedicate some of their power to create artificial noise is proposed and shown to outperform both time-sharing and simple multiplexed transmission of the confidential messages.
Quasi-maximum likelihood estimation for conditional quantiles

In this paper we derive the asymptotic distribution of a new class of quasi-maximum likelihood estimators (QMLE) based on a ‘tick-exponential’ family of densities. We show that the ‘tick-exponential’ assumption is a necessary and sufficient condition for a QMLE to be consistent for the parameters of a correctly specified model of a given conditional quantile. Hence, the role of this family of densities in the conditional quantile estimation is analog to the role of the linear-exponential family in the conditional mean estimation. The ‘tick-exponential’ QMLEs are shown to be asymptotically normal with an asymptotic covariance matrix that has a novel form, not seen in earlier work, and which accounts for possible model misspecification. For practical purposes, we show that the maximization of the ‘tick-exponential’ (quasi) log-likelihood can conveniently be carried out by using standard gradient-based optimization techniques. More importantly, we provide a consistent estimator for the asymptotic covariance matrix based on the “scores” of the log-likelihood, which allows us to compute the conditional quantile confidence intervals.
Laser absorption measurements of OH concentration and temperature in pulsed facilities

A laser absorption flow diagnostic application has been developed at the NASA Ames 16-inch Shock Tunnel for purposes of measuring the thermochemical state of OH in flow environments of interest. Research objectives include the investigation of high temperature, low pressure chemistry pertinent to scramjet combustors and high altitude flight. The system can be operated in either the fixed frequency mode or in the rapid wavelength scanning mode to measure species mole fraction and temperature. Emission diagnostics have been employed to determine shock tunnel flow quality and assist in the proper application of the diagnostic and its data interpretation. Rotational lines in the OH system were probed in the expanding facility nozzle flow, and time-resolved measurements of temperature and mole fraction are provided.
F-Polynomials in Quantum Cluster Algebras

F-polynomials and g-vectors were defined by Fomin and Zelevinsky to give a formula which expresses cluster variables in a cluster algebra in terms of the initial cluster data. A quantum cluster algebra is a certain noncommutative deformation of a cluster algebra. In this paper, we define and prove the existence of analogous quantum F-polynomials for quantum cluster algebras. We prove some properties of quantum F-polynomials. In particular, we give a recurrence relation which can be used to compute them. Finally, we compute quantum F-polynomials and g-vectors for a certain class of cluster variables, which includes all cluster variables in type $\mbox{A}_{n}$ quantum cluster algebras.
Group-theoretic constructions of erasure-robust frames

In the field of compressed sensing, a key problem remains open: to explicitly construct matrices with the restricted isometry property (RIP) whose performance rivals those generated using random matrix theory. In short, RIP involves estimating the singular values of a combinatorially large number of submatrices, seemingly requiring an enormous amount of computation in even low-dimensional examples. In this paper, we consider a similar problem involving submatrix singular value estimation, namely the problem of explicitly constructing numerically erasure robust frames (NERFs). Such frames are the latest invention in a long line of research concerning the design of linear encoders that are robust against data loss. We begin by focusing on a subtle di erence between the definition of a NERF and that of an RIP matrix, one that allows us to introduce a new computational trick for quickly estimating NERF bounds. In short, we estimate these bounds by evaluating the frame analysis operator at every point of an "-net for the unit sphere. We then borrow ideas from the theory of group frames to construct explicit frames and "-nets with such high degrees of symmetry that the requisite number of operator evaluations is greatly reduced. We conclude with numerical results, using these new ideas to quickly produce decent estimates of NERF bounds which would otherwise take an eternity. Though the more important RIP problem remains open, this work nevertheless demonstrates the feasibility of exploiting symmetry to greatly reduce the computational burden of similar combinatorial linear algebra problems.
Feature-level Fusion for Object Segmentation using Mutual Information

We present a new feature-level image fusion technique for object segmentation based on mutual information. Using object regions roughly detected from one sensor as input, the proposed technique extracts relevant information from another to complete the segmentation. First, a contourbased feature representation is presented that implicitly captures object shape. The notion of relevance across sensor modalities is then defined using mutual information computed based on the affinity between contour features. Finally a heuristic selection scheme is proposed to identify the set of contour features having the highest mutual information with the input object regions. The approach works directly from the input image pair without relying on a training phase. Results are presented for segmenting people from background, and quantitatively evaluated.
Efficient Steiner tree construction based on spanning graphs

The Steiner Minimal Tree (SMT) problem is a very important problem in very large scale integrated computer-aided design. Given n points on a plane, an SMT connects these points through some extra points (called Steiner points) to achieve a minimal total length. Even though there exist many heuristic algorithms for this problem, they have either poor performances or expensive running time. This paper records an implementation of an efficient SMT algorithm that has a worst case running time of O(nlogn) and a performance close to that of the Iterated 1-Steiner algorithm. The algorithm efficiently combines Borah et al.'s edge substitute concept with Zhou et al.'s spanning graph. Extensive experimental studies are conducted to compare it with other programs.
Genomic Flexibility of Human Endogenous Retrovirus Type K

Human endogenous retrovirus type K (HERV-K) proviruses are scattered throughout the human genome, but as no infectious HERV-K virus has been detected to date, the mechanism by which these viruses replicated and populated the genome remains unresolved. Here, we provide evidence that, in addition to the RNA genomes that canonical retroviruses package, modern HERV-K viruses can contain reverse-transcribed DNA (RT-DNA) genomes. Indeed, reverse transcription of genomic HERV-K RNA into the DNA form is able to occur in three distinct times and locations: (i) in the virus-producing cell prior to viral release, yielding a DNA-containing extracellular virus particle similar to the spumaviruses; (ii) within the extracellular virus particle itself, transitioning from an RNA-containing particle to a DNA-containing particle; and (iii) after entry of the RNA-containing virus into the target cell, similar to canonical retroviruses, such as murine leukemia virus and HIV. Moreover, using a resuscitated HERV-K virus construct, we show that both viruses with RNA genomes and viruses with DNA genomes are capable of infecting target cells. This high level of genomic flexibility historically could have permitted these viruses to replicate in various host cell environments, potentially assisting in their many integration events and resulting in their high prevalence in the human genome. Moreover, the ability of modern HERV-K viruses to proceed through reverse transcription and package RT-DNA genomes suggests a higher level of replication competency than was previously understood, and it may be relevant in HERV-K-associated human diseases. IMPORTANCE Retroviral elements comprise at least 8% of the human genome. Of all the endogenous retroviruses, HERV-K viruses are the most intact and biologically active. While a modern infectious HERV-K has yet to be found, HERV-K activation has been associated with cancers, autoimmune diseases, and HIV-1 infection. Thus, determining how this virus family became such a prevalent member of our genome and what it is capable of in its current form are of the utmost importance. Here, we provide evidence that HERV-K viruses currently found in the human genome are able to proceed through reverse transcription and historically utilized a life cycle with a surprising degree of genomic flexibility in which both RNA- and DNA-containing viruses were capable of mediating infection.
The Value Relevance of Greenhouse Gas Emissions Allowances: An Exploratory Study in the Related United States SO2 Market

This paper examines the valuation implications of greenhouse gas (GHG) emissions allowances. We posit that the value of a firm's bank of emission allowances has two components that are likely to be positively valued by the capital market: (1) an asset value component; and (2) a real option value component. Since the necessary data to examine this research hypothesis in the setting of GHG emission allowances is not yet available, we test our conjecture by examining the value relevance of sulfur dioxide (SO2) emission allowances held by US electric utilities. Empirical results reveal that the capital market assigns a positive price to a firm's bank of SO2 emission allowances, consistent with the argument that emission allowances have, at least, an asset value component that is assigned a positive price by the market. We also find weak evidence consistent with the market assigning a real option value to the allowance banks.
Total Synthesis of (±)-Mitorubrinic Acid

(±)-Mitorubrinic acid, a member of the azaphilone family of natural products, has been constructed in 12 steps. Key aspects of the synthesis include elaboration and oxidative dearomatization of an isocoumarin intermediate to provide the azaphilone nucleus with a disubstituted, unsaturated carboxylic acid side chain.
Regioselective and enantiospecific rhodium-catalyzed allylic amination with thymine : synthesis of a new conformationally rigid nucleoside

The regioselective and enantiospecific rhodium-catalyzed allylic amination of secondary allylic carbonates with N3-benzoyl thymine in conjunction with a stereoselective free radical cyclization provides a convenient method for the construction of a new conformationally rigid nucleoside.
TEG: a new post-layout optimization method

Post-layout is an important stage in the modern very large scale integration (VLSI) design. In this stage, the extraction and verification tools can get the most accurate results with the complete layout information, and the layout problems can be detected precisely for further design improvements or optimizations. But the problem is that the design optimization is very hard to perform in post-layout. Every design modification is under tight geometry constraints. Usually the designer either changes layout manually by layout editor, or goes back to previous placement or routing stage in order to have the preferred results. How to modify the layout becomes a bottleneck in the post-layout optimization. In this paper, we propose a new method to resolve this problem called the triangulation encoding graph (TEG) method. Based on an improved topological layout representation and a set of layout operation algorithms, TEG provides an incremental layout modification environment for post-layout optimizations. Experimental results show that TEG is efficient and effective in processing industry VLSI designs.
Numerical Treatment of. Cylindrical Coordinate Centerline Singularities

Abstract The grid singularity located at the centerline in a cylindrical coordinate system can exhibit numerical instabilities when finite differences are used to approximate the spatial derivatives contained in the equations of fluid motion. Results from previous work has indicated that the root cause of centerline instability is due to the error from the finite difference approximation of the azimuthal derivatives and not the radial derivative treatment. Using a simple test case, several formulations of the governing equations for a 2-D polar grid are investigated analytically, then tested numerically. It is demonstrated that the azimuthal derivative error can be amplified or cancelled, depending on the particular formulation of the governing equations used, and that this error is the cause of numerical instabilities at the centerline.
Analysis and Optimization of Externally Stiffened Crush Tubes

Nonlinear finite element analysis is used to investigate the quasi-static axial collapse response of cylindrical tubes which are externally stiffened by multiple identical rings. The rings divide the long tube into a series of short thin-walled tubes. It is assumed that the size and shape of integral stiffeners are controlled through a machining process. The effects of various geometric parameters such as wall thickness, ring spacing, ring thickness and width on the collapse response, crush force and energy absorption of monolithic, integrally stiffened steel tubes are studied and used as a general framework for a design optimization study. Through design and analysis of computer experiments, global metamodels are developed for the mean crush force and energy absorption, using the radial basis function approximation technique. Using both single- and multi-objective design optimization formulations, optimum designs for different response characteristics are found. The crush mode in the form of progressive collapse or buckling is found to heavily depend on the ratio of stiffener spacing to stiffener height as well as the ratio of wall thickness to stiffener thickness. The optimization results show the viability of externally stiffened tubes as efficient energy absorbers.
An integrated model for accurate shape alignment

In this paper, we propose a two-level integrated model for accurate face shape alignment. At the low level, the shape is split into a set of line segments which serve as the nodes in the hidden layer of a Markov Network. At the high level, all the line segments are constrained by a global Gaussian point distribution model. Furthermore, those already accurately aligned points from the low level are detected and constrained using a constrained regularization algorithm. By analyzing the regularization result, a mask image of local minima is generated to guide the distribution of Markov Network states, which makes our algorithm more robust. Extensive experiments demonstrate the accuracy and effectiveness of our proposed approach.
Flexible pricing: an approach to the allocation of computer resources

The past twenty years have seen the rapid development of an extremely powerful new tool---namely the electronic digital computer. The technology associated with these machines has advanced rapidly, permitting the development of capabilities which only a few short years ago would have staggered the imagination. Man has been equally progressive with respect to the application of this tool in his endeavors. In particular, the area of business management has built rapidly upon the advantages offered by computer processing. Although the computer only served as a glorified bookkeeping machine in the earliest applications, its usage quickly developed.
Commissioning of a high-brightness photoinjector for compton scattering x-ray sources

Compton scattering of intense laser pulses with ultra- relativistic electron beams has proven to be an attractive source of high-brightness x-rays with keV to MeV energies. This type of x-ray source requires the electron beam brightness to be comparable with that used in x-ray free- electron lasers and laser and plasma based advanced accelerators. We describe the development and commissioning of a 1.6 cell RF photoinjector for use in Compton scattering experiments at LLNL. Injector development issues such as RF cavity design, beam dynamics simulations, emit- tance diagnostic development, results of sputtered magnesium photo-cathode experiments, and UV laser pulse shaping are discussed. Initial operation of the photoinjector is described.
Differential space-time modulation

Space-time coding and modulation exploit the presence of multiple transmit antennas to improve the performance on multipath radio channels. Thus far, most work on space-time coding has assumed that perfect channel estimates are available at the receiver. In certain situations, however, it may be difficult or costly to estimate the channel accurately, in which case it is natural to consider the design of modulation techniques that do not require channel estimates at the transmitter or receiver. We propose a general approach to differential modulation for multiple transmit antennas based on group codes. This approach ran be applied to any number of transmit and receive antennas, and any signal constellation. We also derive low-complexity differential receivers, error bounds, and modulator design criteria, which we use to construct optimal differential modulation schemes for two transmit antennas. These schemes can be demodulated with or without channel estimates. This permits the receiver to exploit channel estimates when they are available. The performance degrades by approximately 3 dB when estimates are not available.
A Tale of Two Cities and a Giffen Good

A scenario is provided in which a house in Eden Mills, Ontario, is a Giffen good. The conditions derived in the example apply to other indivisible goods as well. JEL classification: D11
AREA-EFFICIENT ORDER-PRESERVING PLANAR STRAIGHT-LINE DRAWINGS OF ORDERED TREES

Ordered trees are generally drawn using order-preserving planar straight-line grid drawings. We investigate the area-requirements of such drawings and present several results. Let T be an ordered tree with n nodes. We show that: • T admits an order-preserving planar straight-line grid drawing with O(n log n) area. • If T is a binary tree, then T admits an order-preserving planar straight-line grid drawing with O(n loglog n) area. • If T is a binary tree, then T admits an order-preserving upward planar straight-line grid drawing with optimalO(n log n) area. We also study the problem of drawing binary trees with user-specified aspect ratios. We show that an ordered binary tree T with n nodes admits an order-preserving planar straight-line grid drawing with area O(n log n), and any user-specified aspect ratio in the range [1,n/log n]. All the drawings mentioned above can be constructed in O(n) time.
Fault-tolerant wormhole routing algorithms in meshes in the presence of concave faults

A fault ring is a connection of only nonfaulty adjacent nodes and links such that the interior of the ring contains only faulty components. This paper proposes two wormhole routing algorithms that deal with more relaxed shapes of fault rings than previously known algorithms in the mesh networks. As a result, the number of components to be made disabled would be reduced considerably in some cases. First algorithm, called F4, uses four virtual channels and allows all four sides of fault rings to contain concave shapes. Second algorithm, F3, permits up to three sides to contain concave shapes using only three virtual channels. Both F3 and F4 are free of deadlock and livelock and guarantee the delivery of messages between any pair of nonfaulty and connected nodes in the network.
Improved and Scalable Synthetic Route to the Synthon 17-β-(2-Carboxyethyl)-1,3,5(10)-estratriene: An Important Intermediate in the Synthesis of Bone-Targeting Estrogens

An improved, highly scalable methodology for the multigram-scale preparation of an important synthon, 17-β-(2-carboxyethyl)-1,3,5(10)-estratriene, is described. Previous approaches have failed to provide useful quantities of the analytically pure product because of facile retro-Michael breakdown of the β-alkoxy carbonyl precursors during workup and isolation operations. The synthetic approach described herein has been designed specifically to sidestep this problematic breakdown process. This new scalable method of preparation overcomes a major hurdle in the exploration of structure–activity relationships centered around novel estradiol derivatives with bone-targeting properties and also provides a scalable process for subsequent developmental work.
EFFICIENCY OF LARGE DOUBLE AUCTIONS

We consider large double auctions with private values. Values need be neither symmetric nor independent. Multiple units may be owned or desired. Participation may be stochastic. We introduce a very mild notion of "a little independence." We prove that all nontrivial equilibria of auctions that satisfy this notion are asymptotically efficient. For any alpha > 0, inefficiency disappears at rate 1/n(2-alpha).
The space of embedded minimal surfaces of fixed genus in a 3-manifold V; Fixed genus

This paper is the fifth and final in a series on embedded minimal surfaces. Following our earlier papers on disks, we prove here two main structure theorems for \itnonsimply connected embedded minimal surfaces of any given fixed genus. The first of these asserts that any such surface without small necks can be obtained by gluing together two oppositely-oriented double spiral staircases. The second gives a pair of pants decomposition of any such surface when there are small necks, cutting the surface along a collection of short curves. After the cutting, we are left with graphical pieces that are defined over a disk with either one or two sub-disks removed (a topological disk with two sub-disks removed is called a pair of pants). Both of these structures occur as different extremes in the two-parameter family of minimal surfaces known as the Riemann examples
Entrepreneurship in Japan’s ICT Sector: Opportunities and Protection from Japan’s Telecommunications Regulatory Regime Shift

Entrepreneurs and entrepreneurship played a critical role in transforming Japan’s telecommunications sector. Between the mid-1990s and mid-2000s, in a sector long dominated by a stable set of large actors with wellestablished patterns of interaction, entrepreneurs introduced new technologies, new business models, and new norms of interaction. The subsequent transformation of Japan’s telecommunications sector was dramatic, providing consumers with not only fast and sophisticated services but also low prices and an entire new ecosystem of mobile content—a considerable departure from Japan’s long track record of being known as producer- rather than consumer-oriented, with consumers enjoying high-end services and products, but at high prices. Yet, these transformative entrepreneurs were not acting in a vacuum. Regulatory shifts in telecommunications were critical in providing opportunities for entrepreneurs, while simultaneously protecting them from large incumbent firms. These regulatory shifts were driven by the political dynamics of the 1990s as Japan struggled through its post-bubble economic malaise and political changes.
How Common are Engines in Ib/c Supernovae?

The association of γ-ray bursts (GRBs) and core-collapse supernovae (SNe) of Type Ib and Ic was motivated by the detection of SN 1998bw in the error box of GRB980425 and the now-secure identification of a SN 1998bw-like event in the cosmological GRB030329. The bright radio emission from SN 1998bw indicated that it possessed some of the unique attributes expected of GRBs, namely a large reservoir of energy in (mildly) relativistic ejecta and variable energy input. Here we discuss the results of a systematic program of radio observations of most reported Type Ib/c SNe accessible to the Very Large Array, designed to determine the fraction of Type Ib/c SNe driven by an engine. We conclude that: (i) the incidence of such events is low, < 3%, and (ii) there appears to be a clear dichotomy between the majority of hydrodynamic explosions (SNe) and engine-driven explosions (GRBs).
Performance assessment of advanced ocean current sensors

Laboratory tests were performed by NOAA/NOS's Test and Evaluation Laboratory (T&EL) on a new electromagnetic-type current sensor and a new acoustic-type current sensor. The simulation methods are described for attaining a performance description of the sensor's dynamic response and steady flow characteristics in the laboratory. Test results and data interpretation are discussed.
Equilibrium Analysis of Portfolio Insurance

A martingale approach is used to characterize general equilibrium in the presence of portfolio insurance. Insurers sell to noninsurers in bad states, and general equilibrium requires that the risk premium rises to induce noninsurers to increase their holdings. We show that portfolio insurance increases price volatility, causes mean reversion in asset returns, raises the Sharpe ratio and volatility in bad states, and causes volatility to be correlated with volume. We also explain why out-of-the-money SP that is, the demand for an absolute level of price protection is equivalent to a demand for put options.1 We show that a similar argument can be used in a
Intonational Boundaries, Speech Repairs, and Discourse Markers: Modeling Spoken Dialog

To understand a speaker's turn of a conversation, one needs to segment it into intonational phrases, clean up any speech repairs that might have occurred, and identify discourse markers. In this paper, we argue that these problems must be resolved together, and that they must be resolved early in the processing stream. We put forward a statistical language model that resolves these problem, does POS tagging, and can be used as the language model of a speech recognizer. We find that by accounting for the interactions between these tasks that the performance on each task improves, as does POS tagging and perplexity.
The Gender Wage Gap and Poverty in Colombia

Using 19 years of cross-section wage data, we look at two factors that may explain the lower wages earned by women as compared to men in Colombia. First, we observe a long-term trend towards an increase in the gender wage gap which may be related to new labor regulations giving more protection to women and thereby raising the cost of female employment for firms. Second, as predicted by the literature, we observe an inverse relationship between the relative supply of labor by women and the gender wage gap. The combination of these two factors has led to an increase in the wage gender gap over the period in review, which in turn has led to an increase in relative poverty because less educated women were affected the most by the underlying trends.
Optimization of Performance Characteristics of Electropneumatic (Two-Stage) Servo Valve

Servo valve is the key element in electropneumatic servomechanism. In this study, an electropneumatic two-stage servo valves were investigated in order to improve their static and dynamic characteristics. These servo valves consist of a pilot stage and a power stage. The paper discusses three different pilot stages: the jet pipe pilot stage, the supply (side) flapper nozzle pilot stage and the exhaust (side) flapper nozzle pilot stage. The static and dynamic characteristics of the devices were investigated analytically and by computer simulation. For the three pilot stage types it was found that the optimal value of the static and dynamic characteristics could be obtained if the ratio between the effective areas of the supply channel and exhaust port of the pilot stage has a definite value (depending on the pilot stage type).
General synthesis of phosphatidylinositol 3-phosphates

Uniform synthetic approach to phosphatidylinositol 3-phosphate, 3,4-bisphosphate and 3,4,5-trisphosphate has been elaborated starting from 1D-1-O-tert-butyldiphenylsilyl- and 1,6-O-(1,1,3,3-tetraisopropyldisiloxane-1,3-diyl)-myo-inositols using regioselective benzoylation at the 3-, 3,4- and 3,4,5-positions of inositol.
Searching with numbers

A large fraction of the useful Web is comprised of specification documents that largely consist of (attribute name, numeric value) pairs embedded in text. Examples include product information, classified advertisements, resumes, etc. The approach taken in the past to search these documents by first establishing correspondences between values and their names has achieved limited success because of the difficulty of extracting this information from free text. We propose a new approach that does not require this correspondence to be accurately established. Provided the data has "low reflectivity", we can do effective search even if the values in the data have not been assigned attribute names and the user has omitted attribute names in the query. We give algorithms and indexing structures for implementing the search. We also show how hints (i.e., imprecise, partial correspondences) from automatic data extraction techniques can be incorporated into our approach for better accuracy on high reflectivity data sets. Finally, we validate our approach by showing that we get high precision in our answers on real data sets from a variety of domains.
Molecular structures of gaseous dichloro- and dibromo(dioxo)molybdenum(VI). Are the Mo O bond distances and the O Mo O bond angles similar?

Abstract The molecular structures of dichloro- and dibromo(dioxo)molybdenum(VI), MoO2Cl2 and MoO2Br2, have been reinvestigated by electron diffraction at nozzle-tip temperatures of 100 and 170°C, respectively. The purpose was to check the results of two earlier studies in which significant differences in the values of the Mo  O bond distance and the O  Mo  O bond angle were reported. We find that the values of each of these parameters are similar in the two compounds. Our results (rg(A) and ∠α(deg) with estimated 2σ uncertainties), based on assumed C2v molecular symmetry, are as follows. MoO2Cl2: r(Mo  O) = 1.686(4); r(MoCl) = 2.258(3); ∠ O  Mo  O = 106.3(26); ∠ ClMoCl = 113.9(23). MoO2Br2: r(Mo  O) = 1.683(6); r(MoBr) = 2.403(3); ∠ O  Mo  O = 107.8(39); ∠ BrMoBr = 111.7(12).
A Computational Routine for Disaggregating Industry Margin Data to Estimate Product Margin Rates

Retail industry product margin rates are used to estimate the retail output proportion of final consumption commodities. The Census Bureau collects data on industry margin rates, but it does not collect product margin rate data. To estimate retail industry-by-commodity output, industry margin rates are disaggregated by product. A number of controls are available for disaggregating industry data. This paper introduces a formal computational method for disaggregating industry margin data using Bayesian statistics and simulation. The routine is capable of accurately imposing multiple controls simultaneously. The method's accuracy is demonstrated by an evaluation of its industry product margin rate estimates. In addition to producing accurate disaggregate estimates, the method is fast and its estimates are replicable. The computational method has a broad range of applications beyond the estimation of industry-by-product margin rates.
An Estimate of Iran's Underground Economy: A Monetary Approach.

It is important to note that in rationalizing the low GDP, there are those who believe that the officially reported GDP is only a part of the total actual real GDP. That is, some believe that a large part of Iranian economy is not reported. Therefore, there is a great deal of underground (unreported) economic activities in Iran that are not included in the reported data. Even though one cannot deny the existence of this unofficial underground economy, it cannot be shown that they are not included in the official data reported by the Central Bank of Iran. Therefore, we can safely assume that, by all approximations, the official data to be a good representative of actual real Iranian economy and the proposition of much larger economy due to the existence of a large underground economy beyond and in addition to the officially published data is, more or less, an exaggeration.
Model projections of rapid sea-level rise on the northeast coast of the United States

Human-induced climate change is expected to cause sea-level rise globally as well as regionally. An analysis of state-of-the-art climate models indicates that the northeastern US coast is particularly likely to experience substantial rises in regional sea level as a result of the projected slowdown of the Atlantic meridional overturning circulation. Human-induced climate change could cause global sea-level rise. Through the dynamic adjustment of the sea surface in response to a possible slowdown of the Atlantic meridional overturning circulation1,2, a warming climate could also affect regional sea levels, especially in the North Atlantic region3, leading to high vulnerability for low-lying Florida and western Europe4,5,6. Here we analyse climate projections from a set of state-of-the-art climate models for such regional changes, and find a rapid dynamical rise in sea level on the northeast coast of the United States during the twenty-first century. For New York City, the rise due to ocean circulation changes amounts to 15, 20 and 21 cm for scenarios with low, medium and high rates of emissions respectively, at a similar magnitude to expected global thermal expansion. Analysing one of the climate models in detail, we find that a dynamic, regional rise in sea level is induced by a weakening meridional overturning circulation in the Atlantic Ocean, and superimposed on the global mean sea-level rise. We conclude that together, future changes in sea level and ocean circulation will have a greater effect on the heavily populated northeastern United States than estimated previously7,8,9.
Black holes, AdS, and CFTs

This brief conference proceeding attempts to explain the implications of the anti-de Sitter/conformal field theory (AdS/CFT) correspondence for black hole entropy in a language accessible to relativists and other non-string theorists. The main conclusion is that the Bekenstein–Hawking entropy S BH is the density of states associated with certain superselections sectors, defined by what may be called the algebra of boundary observables. Interestingly while there is a valid context in which this result can be restated as “S BH counts all states inside the black hole,” there may also be another in which it may be restated as “S BH does not count all states inside the black hole, but only those that are distinguishable from the outside.” The arguments and conclusions represent the author’s translation of the community’s collective wisdom, combined with a few recent results.
Functional Gold Nanorods: Synthesis, Self-Assembly, and Sensing Applications

Gold nanorods have received much attention due to their unique optical and electronic properties which are dependent on their shape, size, and aspect ratio. This article covers in detail the synthesis, functionalization, self-assembly, and sensing applications of gold nanorods. The synthesis of three major types of rods is discussed: single-crystalline and pentahedrally-twinned rods, which are synthesized by wet chemistry methods, and polycrystalline rods, which are synthesized by templated deposition. Functionalization of these rods is usually necessary for their applications, but can often be problematic due to their surfactant coating. Thus, general strategies are provided for the covalent and noncovalent functionalization of gold nanorods. The review will then examine the significant progress that has been made in controllable assembly of nanorods into various arrangements. This assembly can have a large effect on measurable properties of rods, making it particularly applicable towards sensing of a variety of analytes. Other types of sensing not dependent on nanorod assembly, such as refractive-index based sensing, are also discussed.
α-Substituted acylsilanes via a highly selective [1,4]-Wittig rearrangement of α-benzyloxyallylsilane

α-Benzyloxyallylsilane undergoes efficient [1,4]-Wittig rearrangement to generate an enolate intermediate that can be trapped with various electrophiles, thereby providing a new synthetic approach to substituted acylsilanes.
Methods for message routing in parallel machines

Abstract In this paper, we survey many of the approaches that have been proposed for solving communication problems in parallel machines. The material is presented from a theoretician's perspective, although the paper was written for a general audience.
Numerical Study of Blood Flow at the End-to-Side Anastomosis of a Left Ventricular Assist Device for Adult Patients

We use an implicit large eddy simulation (ILES) method based on a finite volume approach to capture the turbulence in the anastomoses of a left ventricular assist device (LVAD) to the aorta. The order-of-accuracy of the numerical schemes is computed using a two-dimensional decaying Taylor-Green vortex. The ILES method is carefully validated by comparing to documented results for a fully developed turbulent channel flow at Re τ = 395. Two different anastomotic flows (proximal and distal) are simulated for 50% and 100% LVAD supports and the results are compared with a healthy aortic flow. All the analyses are based on a planar aortic model under steady inflow conditions for simplification. Our results reveal that the outflow cannulae induce high exit jet flows in the aorta, resulting in turbulent flow. The distal configuration causes more turbulence in the aorta than the proximal configuration. The turbulence, however, may not cause any hemolysis due to low Reynolds stresses and relatively large Kolmogorov length scales compared with red blood cells. The LVAD support causes an acute increase in flow splitting in the major branch vessels for both anastomotic configurations, although its long-term effect on the flow splitting remains unknown. A large increase in wall shear stress is found near the cannulation sites during the LVAD support. This work builds a foundation for more physiologically realistic simulations under pulsatile flow conditions.