cssi/SciSciGPT-SciSciNet huggingface dataset:
Systematic procedures for digital system realization from logic design to production

A simple, systematic procedure is presented for converting Integrated Circuit Packages (ICP's) and logical designs, first to test breadboards and prototypes and later through ascending packaging compatibility to production models. Emphasis is placed on a minimum number of human decisions, rapid design turnaround time, and available techniques using minimum cost capital equipment. The basic procedure produces two-layer printed circuit boards. A simple extension allows direct conversion to a high density multi-layer system.
Utility-based abstraction and categorization

We take a utility-based approach to categorization. We construct generalizations about events and actions by considering losses associated with failing to distinguish among detailed distinctions in a decision model. The utility-based methods transform detailed states of the world into more abstract categories comprised of disjunctions of the states. We show how we can cluster distinctions into groups of distinctions at progressively higher levels of abstraction, and describe rules for decision making with the abstractions. The techniques introduce a utility-based perspective on the nature of concepts, and provide a means of simplifying decision models used in automated reasoning systems. We demonstrate the techniques by describing the capabilities and output of TUBA, a program for utility-based abstraction.
EXPLAINING ECONOMIC LINKAGES BETWEEN FARMS AND LOCAL COMMUNITIES: LOOKING BEYOND FARM SIZE

We explore the economic linkage between farms and neighboring communities using primary data collected from a state-wide cross section of 461 dairy farms. Empirical results implicate not only farm characteristics such as size, operator tenure and ethnicity but also the characteristics of the local community.
On Balanced Subgroups of the Multiplicative Group

A subgroup H of \({(\mathbb{Z}/d\mathbb{Z})}^{\times }\) is called balanced if every coset of H is evenly distributed between the lower and upper halves of \({(\mathbb{Z}/d\mathbb{Z})}^{\times }\), i.e., has equal numbers of elements with representatives in (0, d ∕ 2) and (d ∕ 2, d). This notion has applications to ranks of elliptic curves. We give a simple criterion in terms of characters for a subgroup H to be balanced, and for a fixed integer p, we study the distribution of integers d such that the cyclic subgroup of \({(\mathbb{Z}/d\mathbb{Z})}^{\times }\) generated by p is balanced.
Diffusion at the Magnetopause: A Theoretical Perspective

This paper discusses theoretical aspects of cross-field wave-particle transport at the magnetopause. The basic framework for calculating the transport based on second order-theory is reviewed. Instabilities that give rise to the waves which then lead to particle scattering and diffusion are discussed, and in particular, the lower hybrid drift instability is emphasized. The linear and nonlinear properties of this instability are presented, along with results from revelant computer simulations. Other potential diffusion processes at the magnetopause are also described. The overall conclusion, supported by wave and particle observations, is that wave-particle diffusion is a relatively weak process at the magnetopause. Further, it is argued that this line of research, while illuminating potential new mechanisms, cannot address the more important question of diffusion and transport on a spatial scale of many ion gyroradii over a temporal scale of many ion gyroperiods. A new paradigm to examine the global aspects of magnetopause transport on ion scales using hybrid code methods is presented. Results of two-dimensional hybrid simulations show that the structure of the magnetopause for northward interplanetary magnetic field is reproduced, and the resulting transport in this case is due to waves below the ion gyrofrequency. Diffusion in the presence of viscousmore » transport due to the kinetic Kelvin-Helmholtz instability is then discussed. The potential for the study of particle diffusion, viscous interactions and magnetic reconnection simultaneously through this paradigm is also addressed.« less
Requirements in the 21st Century: Current Practice and Emerging Trends

Requirements have remained one of the grand challenges in the design of software intensive systems. In this paper we review the main strands of requirements research over the past two decades and identify persistent and new challenges. Based on a field study that involved interviews of over 30 leading IT professionals involved in large and complex software design and implementation initiatives, we review the current state-of-the-art in the practice of design requirements management. We observe significant progress in the deployment of modeling methods, tools, risk-driven design, and user involvement. We note nine emerging themes and challenges in the requirement management arena: 1) business process focus, 2) systems transparency, 3) integration focus, 4) distributed requirements, 5) layered requirements, 6) criticality of information architectures, 7) increased deployment of COTS and software components, 8) design fluidity and 9) interdependent complexity. Several research challenges and new avenues for research are noted in the discovery, specification, and validation of requirements in light of these requirements features.
Decoherence control in quantum information processing: simple models

We explore a strategy for protecting the evolution of a qubit against the effects of environmental noise based on the application of controlled time-dependent perturbations. In the case of a purely decohering coupling, an explicit sequence of control operations is designed, able to average out the decoherence of the qubit with high efficiency. We argue that, in principle, the effects of arbitrary qubit-environment interactions can be removed through suitable decoupling perturbations acting on the system dynamics over time scales comparable to the correlation time of the environment.
Ages from nuclear cosmochronology.

The long-lived radio nuclides 187Re, 232Th, 238U, 235U, and 244Pu can be used to set limits on the galactic age. The interpretation depends on (1) the production ratios of these isotopes in the appropriate nucleosynthesis site, (2) the time-dependent nucleosynthesis rate during galactic evolution, and (3) the isotopic ratios in the matter which condensed in meteorites at the formation of the solar system 4.6 billion years ago. The results range from 11.6 to 24.6 billion years, given the present uncertainties in the three quantities listed above. They are strongly dependent on variations in the production ratios and the amount of initial enrichment from pre-disk populations. A large initial enrichment tends to reduce predicted galactic ages. The strongest constraints on the age come from the 232Th/238U ratio, while the 235U/238U ratio is sensitive to the time-dependence of the nucleosynthesis rate. The inclusion of the 187Re/187Os pair within the same framework allows consistent solutions, but the intrinsic uncertainties in the Re/Os pair insure that it cannot lead to a more precise age determination. Thus, at present, nucleocosmochronology cannot provide age determinations with smaller uncertainties than those obtained from the analysis of globular cluster ages.
Developing New Nanoprobes from Semiconductor Nanocrystals

In recent years, semiconductor nanocrystal quantum dots havegarnered the spotlight as an important new class of biological labelingtool. Withoptical properties superior to conventional organicfluorophores from many aspects, such as high photostability andmultiplexing capability, quantum dots have been applied in a variety ofadvanced imaging applications. This dissertation research goes along withlarge amount of research efforts in this field, while focusing on thedesign and development of new nanoprobes from semiconductor nanocrystalsthat are aimed for useful imaging or sensing applications not possiblewith quantum dots alone. Specifically speaking, two strategies have beenapplied. In one, we have taken advantage of the increasing capability ofmanipulating the shape of semiconductor nanocrystals by developingsemiconductor quantum rods as fluorescent biological labels. In theother, we have assembled quantum dots and gold nanocrystals into discretenanostructures using DNA. The background information and synthesis,surface manipulation, property characterization and applications of thesenew nanoprobes in a few biological experiments are detailed in thedissertation.
Government Patenting and Technology Transfer

Intellectual property rights such as patents protect new inventions from imitation and competition. Patents' major objective is to provide incentives for invention, sacrificing short-term market efficiency for long-term economic gains. Although patents are primarily granted to private firms, policy changes over the last 25 years have resulted in greater use of patenting by the public sector. This study examines government patenting behavior by analyzing case studies of patenting and licensing by the Agricultural Research Service (ARS) of the U.S. Department of agriculture. ARS uses patenting and licensing as a means of technology transfer in cases in which a technology requires additional development by a private sector partner to yield a marketable product. Licensing revenue is not a major motivation for ARS patenting. More widespread use of patenting and licensing by ARS has not reduced the use of traditional instruments of technology transfer such as scientific publication. Once the decision has been made to patent and license a technology, the structure of the licensing agreement affects technology transfer outcomes. As commercial partners gain experience with the technology and learn more about the market, mutually advantageous revisions to license terms can maintain the incentives through which private companies distribute the benefits of public research.
SALT-GRADIENT SOLAR PONDS: DESIGN, CONSTRUCTION AND POWER PRODUCTION

ABSTRACT Salt-gradient solar ponds are combined solar energy collectors and thermal storage systems. The ponds are made non-convective by the formation of a density-gradient composed of salt solutions whose concentrations increase with depth. The depth of the various layers of the pond determine the efficiency and thermal storage capacity of the system. The construction of the largest such pond in the U.S., 2000 m 2 , was completed in 1978 for approximately $35/m 2 . The pond is estimated to produce 1015 GJ/yr of low-temperature heat at a cost of $8.95/GJ, when the installation costs are amortized over 15 yr. Construction changes are suggested to improve the reliability of the system. Electrical power generation by the use of Rankine cycle turbogenerators connected to solar ponds has been demonstrated in Israel. Feasibility studies are in progress to propose electricity production of up to 2,000 MW for projects near the Dead Sea in Israel, and 600 MW in a proposed project at the California Salton Sea.
New Challenges in Model Checking

In the last 25 years, the notion of performing software verification with logic model checking techniques has evolved from intellectual curiosity to accepted technology with significant potential for broad practical application. In this paper we look back at the main steps in this evolution and illustrate how the challenges have changed over the years, as we sharpened our theories and tools. Next we discuss a typical challenge in software verification that we face today --- and that perhaps we can look back on in another 25 years as having inspired the next logical step towards a broader integration of model checking into the software development process.
Propagation of belief functions: a distributed approach

In this paper, we describe a scheme for propagating belief functions in certain kinds of trees using only local computations. This scheme generalizes the computational scheme proposed by Shafer and Logan1 for diagnostic trees of the type studied by Gordon and Shortliffe, and the slightly more general scheme given by Shafer for hierarchical evidence. It also generalizes the scheme proposed by Pearl for Bayesian causal trees (see Shenoy and Shafer). Pearl's causal trees and Gordon and Shortliffe's diagnostic trees are both ways of breaking the evidence that bears on a large problem down into smaller items of evidence that bear on smaller parts of the problem so that these smaller problems can be dealt with one at a time. This localization of effort is often essential in order to make the process of probability judgment feasible, both for the person who is making probability judgments and for the machine that is combining them. The basic structure for our scheme is a type of tree that generalizes both Pearl's and Gordon and Shortliffe's trees. Trees of this general type permit localized computation in Pearl's sense. They are based on qualitative judgments of conditional independence. We believe that the scheme we describe here will prove useful in expert systems. It is now clear that the successful propagation of probabilities or certainty factors in expert systems requires much more structure than can be provided in a pure production-system framework. Bayesian schemes, on the other hand, often make unrealistic demands for structure. The propagation of belief functions in trees and more general networks stands on a middle ground where some sensible and useful things can be done. We would like to emphasize that the basic idea of local computation for propagating probabilities is due to Judea Pearl. It is a very innovative idea; we do not believe that it can be found in the Bayesian literature prior to Pearl's work. We see our contribution as extending the usefulness of Pearl's idea by generalizing it from Bayesian probabilities to belief functions. In the next section, we give a brief introduction to belief functions. The notions of qualitative independence for partitions and a qualitative Markov tree are introduced in Section III. Finally, in Section IV, we describe a scheme for propagating belief functions in qualitative Markov trees.
LAYERWIDTH: analysis of a new metric for directed acyclic graphs

We analyze a new property of directed acyclic graphs (DAGs), called layerwidth, arising from a useful class of DAGs proposed by Eiter and Lukasiewicz for tractable causal reasoning. First, we establish that the complexity of deciding whether a given graph has a bounded layerwidth is NP-complete. Then we proceed to prove key properties of layerwidth that are helpful in efficiently computing the optimal layerwidth. Finally, we compare this new DAG property to two other important DAG properties: treewidth and bandwidth.
An economic model of user rating in an online recommender system

Economic modeling provides a formal mechanism to understand user incentives and behavior in online systems. In this paper we describe the process of building a parameterized economic model of user-contributed ratings in an online movie recommender system. We constructed a theoretical model to formalize our initial understanding of the system, and collected survey and behavioral data to calibrate an empirical model. This model explains 34% of the variation in user rating behavior. We found that while economic modeling in this domain requires an initial understanding of user behavior and access to an uncommonly broad set of user survey and behavioral data, it returns significant formal understanding of the activity being modeled.
Assessing the Geographic Impact of Higher Food Prices in Guinea

Telling a policy maker that poverty will increase due to the recent increase in food prices is not very useful; telling the policy makers where the impact is likely to be larger is better, so that measures to cope with the impact of the crisis can be targeted to areas that need them the most. This paper shows how to use poverty mapping techniques to assess where higher food prices are likely to hurt the most using Guinea census and survey data as a case study. The results suggest that in the case of a rice price increase, the poorest areas of the country will not be the hardest hit, especially if the potential positive impact of higher food prices on rice producers is taken into account, in which case poverty may decline in some of these areas even if for the country as a whole poverty will increase significantly due to the large share of rice in the household consumption budget.
Heat Kernel Expansions on the Integers

In the case of the heat equation u t =u xx +Vu on the real line, there are some remarkable potentials V for which the asymptotic expansion of the fundamental solution becomes a finite sum and gives an exact formula. We show that a similar phenomenon holds when one replaces the real line by the integers. In this case the second derivative is replaced by the second difference operator L 0. We show if L denotes the result of applying a finite number of Darboux transformations to L 0 then the fundamental solution of u t =Lu is given by a finite sum of terms involving the Bessel function I of imaginary argument.
Aztec Diamonds, Checkerboard Graphs, and Spanning Trees

This note derives the characteristic polynomial of a graph that represents nonjump moves in a generalized game of checkers. The number of spanning trees is also determined.
The Billboard Poetry Project

Figure 1. Top left: Photographed by D. Barney. Poem installed on three consecutive billboards, September 10, 2011, Provo/Springville, Utah. Top right: Photographed by D. Barney. Two workshop participants learning how to create an iron oxide transfer drawing, September 10, 2011, Provo, Utah. Bottom right: Photographed by D. Barney. Photographs with transfer drawings created by workshop facilitator Bryan Hutchinson, September 10, 2011, Provo, Utah. Bottom left: Photographed by Rachel Call. Public event with a portable art gallery, an open microphone for poetry readings, and refreshments, September 10, 2011, Provo, Utah.
Characterization of mountain drainage patterns for GPS-denied UAS navigation augmentation

We present a novel approach to use mountain drainage patterns for GPS-denied navigation of small unmanned aerial systems, such as the ScanEagle, utilizing a down-looking fixed focus monocular imager. Our proposal allows for extension of GPS-denied missions in mountain areas, with no assumption of human-made geographic objects. We leverage the analogy between mountain drainage patterns, human aeteriograms, and human fingerprints, to match local drainage patterns to parallax occlusion maps of geo-registered radar returns (GRRR). The GRRR data may be loaded on-board the aircraft pre-mission to avoid the need for a scanning aperture radar during the mission. For recognition purpose, we represent a given mountain area with a set of spatially distributed mountain minutiae, i.e., details found in the drainage patterns, so that conventional minutiae-based fingerprint matching approaches can be used to match real-time camera images against template images in the training set. We use medical arteriography processing technique to extract the patterns. The minutiae-based representation of mountains is achieved by first exposing mountain ridges and valleys with a series of filters and then extracting mountain minutiae from these ridges/valleys. Our results are experimentally validated on actual terrain data and show the effectiveness of minutiae-based mountain representation method.
Finite Difference Approximation for Linear Stochastic Partial Differential Equations with Method of Lines

A stochastic partial differential equation, or SPDE, describes the dynamics of a stochastic process defined on a space-time continuum. This paper provides a new method for solving SPDEs based on the method of lines (MOL). MOL is a technique that has largely been used for numerically solving deterministic partial differential equations (PDEs). MOL works by transforming the PDE into a system of ordinary differential equations (ODEs) by discretizing the spatial dimension of the PDE. The resulting system of ODEs is then solved by application of either a finite difference or a finite element method. This paper provides a proof that the MOL can be used to provide a finite difference approximation of the boundary value solutions for two broad classes of linear SPDEs, the linear elliptic and parabolic SPDEs.
FADS: a fuzzy anomaly detection system

In this paper, we propose a novel anomaly detection framework which integrates soft computing techniques to eliminate sharp boundary between normal and anomalous behavior. The proposed method also improves data pre-processing step by identifying important features for intrusion detection. Furthermore, we develop a learning algorithm to find classifiers for imbalanced training data to avoid some assumptions made in most learning algorithms that are not necessarily sound. Preliminary experimental results indicate that our approach is very effective in anomaly detection
Quantum online memory checking

The problem of memory checking considers storing files on an unreliable public server whose memory can be modified by a malicious party. The main task is to design an online memory checker with the capability to verify that the information on the server has not been corrupted. To store n bits of public information, the memory checker has s private reliable bits for verification purpose; while to retrieve each bit of public information the checker communicates t bits with the public memory. Earlier work showed that, for classical memory checkers, the lower bound s×t∈Ω(n) holds. In this article we study quantum memory checkers that have s private qubits and that are allowed to quantum query the public memory using t qubits. We prove an exponential improvement over the classical setting by showing the existence of a quantum checker that, using quantum fingerprints, requires only s∈O(logn) qubits of local memory and t∈O(polylog n) qubits of communication with the public memory.
Akrasia and the Rule of Appetite in Plato's Protagoras and Republic

According to a prevalent developmentalist line of interpretation, Plato’s introduction of the three-part soul in Republic 4 was motivated in part by his desire to acknowledge and account for cases of akratic action, and thereby to repudiate the psychology and the conclusions of the earlier dialogue Protagoras . In this paper I reject this interpretation, arguing that countenancing akrasia was never a major philosophical concern for Plato, and a fortiori that it was not his motivation for introducing the tripartite soul. I argue that his moral psychological focus and concern in the Republic was rather on the notion of psychic rule, and on illuminating various ways in which reasoning is corrupted by non-rational desires (rather than overcome by them through brute psychic ‘force’). I then offer an explanation of Plato’s lack of concern for akrasia by appealing to the Protagoras itself. I conclude with a rejection of sharp developmentalism between the two dialogues.
Is deliberation equitable ? evidence from transcripts of village meetings in south India

Deliberative decision-making processes are becoming increasingly important around the world to make important decisions about public and private goods allocation, but there is very little empirical evidence about how they actually work. In this paper the authors use data from India extracted from 131 transcripts of village meetings matched with data from household surveys conducted in the same villages prior to the meetings, to study whose preferences are reflected in the meetings. The meetings are constitutionally empowered to make decisions about public and private goods. The findings show that the more land a person owns, the higher the likelihood her preference is mentioned in the meeting, the longer the amount of time spent discussing this preference, and the higher the likelihood that a decision to provide or repair this public or private good is taken. At the same time, the voices of disadvantaged castes, while not dominating the meeting, are also heard. By contrast, the preferences of Muslims are given less time. High village literacy and the presence of higher level officials during village meetings mitigate the power of the landed, but political reservations for low castes for the post of village president increase the power of the landed.
Market access and the mirage of marketing to the maximum: new measures

Purpose – Globalization means integrating the economy and consumer market with the rest of the world, which involves the removal of restrictions on imports and foreign investment. The purpose of this paper is to examine the implications of globalization on international marketing from the point of multinational firms, in the context of an emerging consumer market – India. Design/methodology/approach – This is a general review-based study with some secondary data analysis. The author introduces new measures for industry analysis. Findings – It was found that Indian market has opened up substantially and there are many foreign players in most sectors. Imports growth rate has gone up substantially during post-World Trade Organization period. The author provides insights based on sector-wise analysis. Originality/value – The most important contribution of this paper is the introduction of two measures for carrying out industry analysis by integrating economics, marketing and strategy a Success-probability Ind...
Analyzing Risky Choices: Q-learning for Deal-No-Deal

In this paper, we derive an optimal strategy for the popular Deal or No Deal game show. To do this, we use Q-learning methods, which quantify the continuation value inherent in sequential decision making in the game. We then analyze two contestants, Frank and Susanne, risky choices from the European version of the game. Given their choices and our optimal strategy, we find what their implied bounds would be on their levels of risk aversion. Previous empirical evidence in risky decision making has suggested that past outcomes affect future choices and that contestants have time-varying risk aversion. We demonstrate that the strategies of Frank and Susanne are consistent with constant risk aversion levels except for their final risk-seeking choice. We conclude with directions for future research. Copyright © 2013 John Wiley & Sons, Ltd.
Data bases: uncontrollable or uncontrolled?

In the last two years the "data base" concept has received as much management publicity as did "Management by Objectives" in the years just prior. The popularity of and recognition given to the power of computing in recent years, coupled with increased awareness of the role the enlightened manager should assume, have encouraged one installation after another to acquire a data base system in the pursuit of modern techniques for information retrieval. As both hardware and software have become cheaper and more widely available, the decision has become easier to make; thus the apparent need for foresight and planning has declined. Unfortunately, all too many people are now seeing the entire data base technology as an impossible dream and discrediting the concept as an expensive toy devised by the ever-hungry computer vendors. This trend is summarized in a brochure for a current seminar on data bases: "No subject in computing history has had the import of data base, nor disaster stories of equal magnitude." And yet the "disasters" are not necessary. With proper foresight and planning and continued supervision, a data base system can produce all the results it promises.
Metrology and quantification of micromilled x-ray masks and exposures

Micromechanical milling has been shown to be a rapid and direct method for the production of x-ray masks with features within the process limits. A method for compensating milling tool run out has been adapted and the tolerance of mask absorber features has been reduced to approximately 0.5 micrometers. The milling process leaves some absorber burrs and the absorber is also tapered at the machined wall which introduces an additional process bias, both of which add to exposure degradation. Nevertheless, both of these effects can be greatly reduced with further work.
A Phase I Report of Paclitaxel Dose Escalation Combined with a Fixed Dose of Carboplatin in the Treatment of Head and Neck Carcinoma

BACKGROUND Standard therapy for advanced head and neck carcinoma is surgery and radiation, and the subsequent 5-year survival with this treatment has been less than 50%. New combined modality treatment strategies are being tested to improve survival. New chemotherapy combinations are being developed and administered simultaneously with, or sequenced with, radiation and surgery. This article reports the Phase I results of administering paclitaxel and carboplatin preoperatively. The authors' objective was to develop an outpatient chemotherapy that would downstage tumors and allow organ preservation with equal or improved survival as compared with standard therapy. METHODS Thirty-six patients with untreated Stage III/IV head and neck carcinoma were treated and were evaluable for toxicity. All patients had lesions that were measurable in perpendicular planes. A nonrandomized, Phase I design was used, according to which cohorts of patients were treated every 21 days with escalating doses of paclitaxel (150-265 mg/m2) given as a 3-hour infusion immediately preceding carboplatin. Premedication was used to avoid acute hypersensitivity reactions. Carboplatin was administered intravenously over 1 hour at a constant dose calculated with the Calvert formula (area under the curve, 7.5). RESULTS The dose-limiting toxicities were neuropathy and thrombocytopenia at a paclitaxel dose of 265 mg/m2. Neutropenic fever was observed in 30% of patients at a paclitaxel dose of 250-265 mg/m2. Other observed adverse effects included pruritus, myalgia, arthralgia, alopecia, nausea, and vomiting. CONCLUSIONS Toxicity was acceptable. The maximum tolerated dose of paclitaxel was 230 mg/m2 without hematopoietic growth factor, or 250 mg/m2 with hematopoietic growth factor, the carboplatin dose held constant, calculated at area under the curve of 7.5. Phase II studies of this combination are warranted in the treatment of these carcinomas. Cancer 1997; 79:2016-23. © 1997 American Cancer Society.
Elastic metamaterials and dynamic homogenization: a review

In this paper, we review the recent advances which have taken place in the understanding and applications of acoustic/elastic metamaterials. Metamaterials are artificially created composite materials which exhibit unusual properties that are not found in nature. We begin with presenting arguments from discrete systems which support the case for the existence of unusual material properties such as tensorial and/or negative density. The arguments are then extended to elastic continuums through coherent averaging principles. The resulting coupled and nonlocal homogenized relations, called the Willis relations, are presented as the natural description of inhomogeneous elastodynamics. They are specialized to Bloch waves propagating in periodic composites and we show that the Willis properties display the unusual behavior which is often required in metamaterial applications such as the Veselago lens. We finally present the recent advances in the area of transformation elastodynamics, charting its inspirations f...
The Redshift Search Receiver 3 mm Wavelength Spectra of 10 Galaxies

The 3 mm wavelength spectra of 10 galaxies have been obtained at the Five College Radio Astronomy Observatory using a new, very broadband receiver and spectrometer, called the Redshift Search Receiver (RSR). The RSR has an instantaneous bandwidth of 37 GHz covering frequencies from 74 to 111 GHz, and has a spectral resolution of 31 MHz (�100 km s −1 ). During tests of the RSR on the FCRAO 14 m telescope the complete 3 mm spectra of the central regions of NGC 253, Maffei 2, NGC1068, IC 342, M82, NGC 3079, NGC 3690, NGC 4258, Arp 220 and NGC 6240 were obtained. Within the wavelength band covered by the RSR, 20 spectral lines from 14 different atomic and molecular species were detected. Based on simultaneous fits to the spectrum of each galaxy, a number of key molecular line ratios are derived. A simple model which assumes the emission arises from an ensemble of Milky Way-like Giant Nolecular Cloud cores can adequately fit the observed line ratios using molecular abundances based on Galactic molecular cloud cores. Variations seen in some line ratios, such as 13 CO/HCN and HCO + /HCN, can be explained if the mean density of the molecular gas varies from galaxy to galaxy. However, NGC 3690, NGC 4258 and NGC 6240 show very large HCO + /HCN ratios and require significant abundance enhancement of HCO + over HCN, possible due to the proximity to active galactic nucleus activity. Finally, the mass of dense molecular gas is estimated and we infer that 25-85% of the total molecular gas in the central regions of these galaxies must have densities greater than 10 4 cm −3 . Subject headings: galaxies: ISM —ISM: Molecules — ISM: Abundances — Radio Lines: galaxies
Changing strategies in natural products chemistry

Scientific strategies for the study of natural products from plants have changed substantially in the past few years for a number of reasons, including advances in technology, new molecules of substantial interest, changing ethical principles for organism collection and heightened awareness of the chemical and biological potential of the tropical rain forests. This review reflects on these changes and discusses, with recent examples, how they have impacted the conduct of natural products chemistry.
Spectral tests of the martingale hypothesis under conditional heteroscedasticity

Abstract We study the asymptotic distribution of the sample standardized spectral distribution function when the observed series is a conditionally heteroscedastic martingale difference. We show that the asymptotic distribution is no longer a Brownian bridge but another Gaussian process. Furthermore, this limiting process depends on the covariance structure of the second moments of the series. We show that this causes test statistics based on the sample spectral distribution, such as the Cramer von-Mises statistic, to have heavily right skewed distributions, which will lead to over-rejection of the martingale hypothesis in favour of mean reversion. A non-parametric correction to the test statistics is proposed to account for the conditional heteroscedasticity. We demonstrate that the corrected version of the Cramer von-Mises statistic has the usual limiting distribution which would be obtained in the absence of conditional heteroscedasticity. We also present Monte Carlo results on the finite sample distributions of uncorrected and corrected versions of the Cramer von-Mises statistic. Our simulation results show that this statistic can provide significant gains in power over the Box–Ljung–Pierce statistic against long-memory alternatives. An empirical application to stock returns is also provided.
A clustering based similarity measure and its application to human action recognition

Computing the similarity between videos is a challenging problem in many applications of video processing such as video retrieval and video-based action recognition. The main difficulty in evaluating similarity between videos is the lack of an effective distance measure. In this paper, we propose a clustering based distance measure to solve this problem. In our approach, a video sequence is represented by a set of spatiotemporal descriptors. Therefore computing the similarity between two video sequences can be achieved by estimating the distance between two sets of descriptors extracted from the videos. To compute the distance measure, we use clustering to obtain distributions and "constrained distributions" of the two sets of descriptors, and use Kullback-Leibler (KL) divergence [6] with the distributions. We apply our distance measure to the problems of distinguishing different human actions and content-based video retrieval. Our experimental results show that the proposed distance measure is an effective metric for these applications.
The onset of dominance in balls-in-bins processes with feedback

Consider a balls-in-bins process in which each new ball goes into a given bin with probability proportional to f(n), where n is the number of balls currently in the bin and f is a fixed positive function. It is known that these so-called balls-in-bins processes with feedback have a monopolistic regime: if f(x) = xp for p > 1, then there is a finite time after which one of the bins will receive all incoming balls. Our goal in this article is to quantify the onset of monopoly. We show that the initial number of balls is large and bin 1 starts with a fraction α > 1-2 of the balls, then with very high probability its share of the total number of balls never decreases significantly below α. Thus a bin that obtains more than half of the balls at a “large time” will most likely preserve its position of leadership. However, the probability that the winning bin has a non-negligible advantage after n balls are in the system is ∼const. × n1-p, and the number of balls in the losing bin has a power-law tail. Similar results also hold for more general functions f. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2009 Part of the work was done while the author was a Ph.D. student at New York University, supported by a CNPq Doctoral Fellowship.
Utilization rates of implantable cardioverter-defibrillators for primary prevention of sudden cardiac death: a 2012 calculation for a midwestern health referral region.

Background Utilization rates (URs) for implantable cardioverter-defibrillators (ICDs) for primary prevention of sudden cardiac death (PPSCD) are lacking in the community. Objective The purpose of this study was to establish the ICD UR in central Indiana. Methods A query run on 2 hospitals in a health information exchange database in Indianapolis identified patients between 2011 and 2012 with left ventricular ejection fraction (EF) ≤0.35. ICD eligibility and utilization were determined from chart review. Results We identified 1863 patients with at least 1 low EF study. Two cohorts were analyzed: 1672 patients without and 191 patients with International Classification of Diseases, Ninth Revision, Clinical Modification procedure code 37.94 for ICD placement. We manually reviewed a stratified (by hospital) random sample of 300 patients from the no-ICD procedure code cohort and found that 48 (16%) had no ICD but had class I indications for ICD. Eight of 300 (2.7%) actually had ICD implantation for PPSCD. Review of all 191 patients in the ICD procedure code cohort identified 70 with ICD implantation for PPSCD. The ICD UR (ratio between patients with ICD for PPSCD and all with indication) was 38% overall (95% confidence interval [CI] 28%–49%). URs were 48% for males (95% CI 34%–61%), 21% for females (95% CI 16%–26%, P = .0002 vs males), 40% for whites (95% CI 27%–53%), and 37% for blacks (95% CI 28%–46%, P = .66 vs whites). Conclusion ICD UR is 38% among patients meeting class I indications, suggesting further opportunities for improving guideline compliance. This study also illustrates limitations in calculating ICD UR using large electronic repositories without hands-on chart review.
Bridge pier live load analysis using neural networks

The positioning of vehicular live loads on a bridge superstructure to achieve the maximum force effects in the bridge pier is an important design issue. For highway bridges, the worst load positioning for the superstructure design usually does not produce the worst force effects for the pier design. As a result, the correct positioning of the loads for the pier is left to engineering judgment. This paper investigates an implementation of neural networks to predict the worst load positioning for the bridge pier. The networks predict the load positioning for both single and multiple column piers given input parameters that describe the pier and bridge configuration. The procedure presented herein is intended to offer an alternative to the trial and error load positioning method used by many practicing engineers.
Stability analysis of one-dimensional asynchronous swarms

Coordinated swarm behavior in certain types of animals can also occur in groups of autonomous vehicles. Swarm "cohesiveness" is characterized as a stability property. Conditions for one-dimensional asynchronous swarms to achieve collision-free convergence even in the presence of sensing delays and asynchronism during movements are provided. Each finite-size swarm member has proximity sensors and neighbor position sensors that only provide delayed position information. Such stability analysis is of fundamental importance if one wants to understand the coordination mechanisms for "platoons" of autonomous vehicles, where intermember communication channels are less than perfect and collisions must be avoided.
An implicit optimization approach for survivable network design

We consider the problem of designing a network of minimum cost while satisfying a prescribed survivability criterion. The survivability criterion requires that a feasible flow must still exists (i.e. all demands can be satisfied without violating arc capacities) even after the disruption of a subset of the network's arcs. Specifically, we consider the case in which a disruption (random or malicious) can destroy a subset of the arcs, with the cost of the disruption not to exceed a disruption budget. This problem takes the form of a tri-level, two-player game, in which the network operator designs (or augments) the network, then the attacker launches a disruption that destroys a subset of arcs, and then the network operator attempts to find a feasible flow over the residual network. We first show how this can be modeled as a two-stage stochastic program from the network operator's perspective, with each of the exponential number of potential attacks considered as a disruption scenario. We then reformulate this problem, via a Benders decomposition, to consider the recourse decisions implicitly, greatly reducing the number of variables but at the expense of an exponential increase in the number of constraints. We next develop a cut-generation based algorithm. Rather than explicitly considering each disruption scenario to identify these Benders cuts, however, we develop a bi-level program and corresponding separation algorithm that enables us to implicitly evaluate the exponential set of disruption scenarios. Our computational results demonstrate the efficacy of this approach.
Embedding multidimensional grids into optimal hypercubes

Abstract Let G and H be graphs, with | V ( H ) | ≥ | V ( G ) | , and f : V ( G ) → V ( H ) a one to one map of their vertices. Let dilation ( f ) = max { dist H ( f ( x ) , f ( y ) ) : x y ∈ E ( G ) } , where dist H ( v , w ) is the distance between vertices v and w of H. Now let B ( G , H ) = min f { dilation ( f ) } , over all such maps f. The parameter B ( G , H ) is a generalization of the classic and well studied “bandwidth” of G, defined as B ( G , P ( n ) ) , where P ( n ) is the path on n points and n = | V ( G ) | . Let [ a 1 × a 2 × ⋯ × a k ] be the k-dimensional grid graph with integer values 1 through a i in the i'th coordinate. In this paper, we study B ( G , H ) in the case when G = [ a 1 × a 2 × ⋯ × a k ] and H is the hypercube Q n of dimension n = ⌈ log 2 ( | V ( G ) | ) ⌉ , the hypercube of smallest dimension having at least as many points as G. Our main result is that B ( [ a 1 × a 2 × ⋯ × a k ] , Q n ) ≤ 3 k , provided a i ≥ 2 22 for each 1 ≤ i ≤ k . For such G, the bound 3k improves on the previous best upper bound 4 k + O ( 1 ) . Our methods include an application of Knuth's result on two-way rounding and of the existence of spanning regular cyclic caterpillars in the hypercube.
Characterizing cryptographic primitives for lightweight digital image encryption

We present a statistical footprint-based method to characterize several symmetric cryptographic primitives as they are used in lightweight digital image encryption. In particular, using spatial-domain histogram and frequency-domain image analysis techniques, we identify a number of metrics from the encrypted images and use them to contrast the security performance of different cryptographic primitives. For each of the metrics, the best performing cryptographic primitive is identified. Complementary primitives are then combined to result in a product cipher with better cryptographic performance.
Practical zero-knowledge proofs: Giving hints and using deficiencies

New zero-knowledge proofs are given for some number-theoretic problems. All of the problems are in NP, but the proofs given here are much more efficient than the previously known proofs. In addition, these proofs do not require the prover to be superpolynomial in power. A probabilistic polynomial-time prover with the appropriate trapdoor knowledge is sufficient. The proofs are perfect or statistical zero-knowledge in all cases except one.
Controlled Fusion Research-An Application of the Physics of High Temperature Plasmas

Some of the long-range implications and advantages of achieving the production of power from controlled fusion reactions between isotopes of hydrogen, helium, and lithium are set forth. The physical conditions which seemingly must be established to accomplish this are presented. These are shown to lead to a situation in which the fusion fuel will exist in the form of a very hot, tenuous, fully ionized gas-i.e., a plasma. It is shown that the required conditions can be maintained only by the use of a force field, for example, a magnetic field, to confine the plasma. A simple example of magnetic confinement?the pinch effect?is described. The electrodynamic properties of a fully ionized gas interacting with a magnetic field are briefly outlined. General scaling laws which would probably apply to any operable controlled fusion reactor are given. Examples are cited of fruitless approaches to the achievement of controlled fusion. Some aspects of the problem of "plasma diagnostics" are described to illustrate means for an experimental approach to high temperature plasma physics.
A hierarchical approach to instruction-level parallelization

In this paper we extend Percolation Scheduling (PS) to navigate through a hierarchical version of the Control Flow Graph (CFG) representation of a VLIW program. This extension retains the completeness of PS by allowing the “normal” PS transformations to be applied incrementally between adjacent instructions but also enablesnonincremental code motions across arbitrarily large single-entry/single-exit regions of code in constant time. Such nonincremental transformations eliminate the useless code explosions that would otherwise be caused by using incremental transformations to move operations through regions containing multiple control paths and, in conjunction with the hierarchical representation of the CFG, provide a framework for trading offuseful code explosions for increases in parallelism. Simulation results comparing nonincremental with incremental PS are presented.
Charge, Geometry, and Effective Mass

Charge, like mass in Newtonian mechanics, is an irreducible element of electromagnetic theory that must be introduced ab initio. Its origin is not properly a part of the theory. Fields are then defined in terms of forces on either masses—in the case of Newtonian mechanics, or charges in the case of electromagnetism. General Relativity changed our way of thinking about the gravitational field by replacing the concept of a force field with the curvature of space-time. Mass, however, remained an irreducible element. It is shown here that the Reissner-Nordstrom solution to the Einstein field equations tells us that charge, like mass, has a unique space-time signature.