Miracle-dz/UniFAR-FTUs huggingface dataset:
Manager perceptions of big data reliability in revenue management

This paper investigates the perceptions that managers have of the value and reliability of using big data to make hotel revenue management and pricing decisions. Whilst big data-driven automated revenue systems are technically capable of making pricing and inventory decisions without user input, the findings here show that the reality is that managers still interact with every stage of the revenue and pricing process from data collection to the implementation of price changes. They believe their personal insights are as valid as big data in increasing the reliability of the decision-making process. This is driven primarily by a lack of trust on the behalf of managers in the ability of the big data systems to understand and interpret local market and customer dynamics. The less a manager believes in the ability of those systems to interpret this data, the more they perceive gut-instinct to increase the reliability of their decision-making and the less they conduct an analysis of the statistical data provided by the systems. This provides a clear message that there appears to be a need for automated revenue systems to be flexible enough for managers to import the local data, information, and knowledge that they believe leads to revenue growth.
Have we so far only seen the tip of the iceberg? Exploring species diversity and distribution of the giant amphipod Eurythenes

Abstract Additional material of the iconic giant amphipod Eurythenes was investigated. Recently, the species E. gryllus has been separated into 12 distinct species-level lineages of which several have been described as distinct species, based on both morphology and genetics. This study revealed three additional species-level lineages from unique sampling localities, showing that with minimal sampling effort, species diversity within Eurythenes can still increase. One species-level lineage was found in the Indian Ocean and another one in the Pacific, which was subsequently identified as E. thurstoni. In addition to the three species already reported from the Southern Ocean (E. maldoror, E. gryllus s.s. and E. andhakarae), a supplementary bathyal species was found in the Weddell Sea. E. gryllus was confirmed to be amphitropical including newly sampled localities around the Kerguelen Islands and additional samples from the Svalbard Archipelago. Building on new and earlier data, geographic and bathymetric distributions of the different species that have been discovered so far are presented here and several factors are evaluated for their likelihood of having triggered past speciation events in this scavenger. Topographic and hydrographical features are discussed but rejected as sufficient reasons for the distributional patterns observed. Bathymetric segregation is interpreted with regard to what is known about the ecology of the species. The previously reported genetic break around 3000 m persists in this new data-set for all species but one. This study underlines the need of processing all individuals sampled, since two or more sympatric species are found in different proportions, and that conclusions regarding diversity and distribution may drastically change when increasing sampling intensity and coverage. Finally, I suggest here that only a mere fraction of all Eurythenes species has yet been discovered and that a more complete knowledge of the ecology of the species is of paramount importance for interpreting their evolution.
On the completion of latin rectangles to symmetric latin squares

Abstract We find necessary and sufficient conditions for completing an arbitrary 2 by n latin rectangle to an n by n symmetric latin square, for completing an arbitrary 2 by n latin rectangle to an n by n unipotent symmetric latin square, and for completing an arbitrary 1 by n latin rectangle to an n by n idempotent symmetric latin square. Equivalently, we prove necessary and sufficient conditions for the existence of an (n−1)-edge colouring of Kn (n even), and for n-edge colouring of Kn (n odd) in which the colours assigned to the edges incident with two vertices are specified in advance.
Stellar surface structures and the astrometric search for exoplanets

Aims. To investigate the astrometric effects of stellar surface structures as a practical limitation to ultra-high-precision astrometry (e.g. in the context of exoplanet searches) and to quantify the expected effects in different regions of the HR-diagram. Methods. Stellar surface structures (spots, plages, granulation, non-radial oscillations) are likely to produce fluctuations in the integrated flux and radial velocity of the star, as well as a variation of the observed photocentre, i.e. astrometric jitter. We use theoretical considerations supported by Monte Carlo simulations (using a starspot model) to derive statistical relations between the corresponding astrometric, photometric, and radial velocity effects. Based on these relations, the more easily observed photometric and radial velocity variations can be used to predict the expected size of the astrometric jitter. Also the third moment of the brightness distribution, interferometrically observable as closure phase, contains information about the astrometric jitter. Results. For most stellar types the astrometric jitter due to stellar surface structures is expected to be of the order of 10 micro-AU or greater. This is more than the astrometric displacement typically caused by an Earth-size exoplanet in the habitable zone, which is about 1-4 micro-AU for long-lived main-sequence stars. Only for stars with extremely low photometric variability (< 0.5 mmag) and low magnetic activity, comparable to that of the Sun, will the astrometric jitter be of the order of 1 micro-AU, sufficient to allow the astrometric detection of an Earth-sized planet in the habitable zone. While stellar surface structure may thus seriously impair the astrometric detection of small exoplanets, it has in general a negligible impact on the detection of large (Jupiter-size) planets and on the determination of stellar parallax and proper motion. From the starspot model we also conclude that the commonly used spot filling factor is not the most relevant parameter for quantifying the spottiness in terms of the resulting astrometric, photometric and radial velocity variations.
Portfolio optimization under partial observation : theoretical and numerical aspects

We give a survey of the methods involved in portfolio selection with partial observation. We describe both the theoretical and numerical aspects related to these optimization problems. The presentation is divided in two parts. In the first one, we focus on continuous-time problem : here, the mean rates of return of the asset prices are not directly observable. Investors observe only asset prices. By the method of change of probability and innovation process in filtering theory, the partial observation portfolio selection problem is transformed into a full observation one with the additional filter state variable, for which one may apply the martingale or PDE approach. We investigate dierent cases for the modelling of the unobervable mean rate of return : Bayesian, linear-Gaussian and finite state Markov chain. In the second part, we consider discretetime optimization problems : this context includes the case of unobservable volatility. We are then concerned with the numerical approximation of the optimization problem under partial observation. This is achieved by performing a quantization of the pair process filter-observation, and using backward dynamic programming formulas. Several numerical experiments illustrate the resuts for hedging problems in the context of partially observed stochastic volatility models.
The effect of genetic polymorphisms on the mechanical heart valve dysfunction Mekanik kalp kapaği disfonksiyonunda genetik polimorfizmlerin etkisi

Amaç: Bu çalışmada, mekanik kalp kapağı disfonksiyonu olan hastalardaki genetik polimorfizmler araştırıldı. Ça­lış­ma­pla­nı:­Ocak 1994 Aralık 2004 tarihleri arasında mekanik kalp kapağı disfonksiyonu nedeni ile yeniden ameliyat edilen hastaların oluşturduğu 18 hasta (grup 1), normal fonksiyonel olan ve mekanik kalp kapağı replasmanı yapılmış, uluslararası normalleştirilmiş oran (INR) düzeyleri düşük olan 15 hasta (grup 2) ve 50 sağlıklı kişi (grup 3) olmak üzere, toplam 83 hasta çalışmaya dahil edildi. Faktör V Leiden, protrombin, interlökin (IL-6) ve tümör nekroz faktör alfa (TNF-a) polimorfizmleri tespit edilerek, mekanik kalp kapağı disfonksiyonu ile olan muhtemel ilişkileri araştırıldı. Bul gu lar: İnterlökin-6 polimorfizmi sonuçları, grup 1 ve grup 3 karşılaştırıldığında anlamlı olarak farklı bulundu (p<0.05). Diğer polimorfizmler ve mekanik kalp kapağı disfonksiyonu açısından gruplar arasında anlamlı bir farklılık görülmedi. İnterlökin-6 G-174C polimorfizmi mekanik kalp kapağı disfonksiyonu ile anlamlı olarak ilişkili bulundu. So­nuç:­ Ana enflamatuvar yanıt sitokini IL-6, muhtemelen devam eden kronik enflamatuvar süreçler ile mekanik kalp kapak disfonksiyonunda etkin bir rol oynayabilir. Anah tar söz cük ler: Genetik polimorfizm; interlökin; mekanik kalp kapağı disfonksiyonu. Background:­ This study aims to investigate genetic polymorphisms in patients with mechanical heart valve dysfunction. Methods: Between January 1994 and December 2004, a total of 83 patients including 18 patients who were reoperated due to mechanical heart valve dysfunction (group 1), 15 patients with normal functions with lower international normalized ratio (INR) levels who underwent mechanical valve replacement (group 2), and 50 healthy individuals (group 3) were included. Factor V Leiden, prothrombin, interleukin (IL-6), and tumor necrosis factor alpha (TNF-a) polymorphisms were investigated for possible relationships between these factors and mechanical heart valve dysfunction. Results:­A significant difference in IL-6 polymorphism was found between group 1 and group 3 (p<0.05). Other polymorphisms were not significantly associated with mechanical heart valve dysfunction among the groups. The IL-6 G-174C polymorphism was found to be significantly associated with mechanical heart valve dysfunction. Conclusion:­Interleukin-6, the key inflammatory response cytokine, may play an effective role in mechanical heart valve dysfunction possibly through ongoing chronic inflammatory processes.
The Ordering of Alliances: Space, Complexity, and Structure Draft Theory Chapter

Alliances have long formed a central concern of International Relations. These partnerships are a key method by which states produce and enhance their security in an anarchical international system (Walt, 1987; Schroeder, 1976), and they have been charged with maintaining stability through the preservation of the balance of power. (Waltz, 1979) Alliances have also been identified as a critical element in the construction of international order (Keohane, 1984; Ikenberry, 2001), organizing, coordinating, and regularizing relations between states on military, security, and even economic and social affairs. This has generated a voluminous body of work assessing the purpose and credibility of alliance commitments. The latter subject has motivated much of the recent work on the effectiveness of allied military action and how states can successfully signal their intentions to both allies and adversaries.
Experimental quantum process tomography of non-trace-preserving maps

The ability of fully reconstructing quantum maps is a fundamental task of quantum information, in particular when coupling with the environment and experimental imperfections of devices are taken into account. In this context, we carry out a quantum process tomography approach for a set of non-trace-preserving maps. We introduce an operator P to characterize the state-dependent probability of success for the process under investigation. We also evaluate the result of approximating the process with a trace-preserving one.
Developing a methodology for the use of COTS operating systems with safety-related software

Conventional wisdom within the System Safety community has been that Commercial-Off-The-Shelf (COTS) Operating Systems (OS) with unknown pedigree are unsuitable for deployment in safety-related systems at anything other than the lowest integrity levels. Without assurance evidence for the OS it is difficult to gain confidence in safe behaviour of the functions provided. The typical solution therefore has been to either develop wholly embedded systems or use operating systems which have been certified to a particular standard. Regulatory and societal expectations on software assurance is continually increasing, however ever-competitive market conditions are causing budgets to remain stable, if not decreased. As modern systems become more complex artefacts, the use of certified operating systems, or development of a bespoke embedded system, present challenges to system designers which are difficult to solve within these budgetary and schedule constraints. Consequently, the use of generic COTS OS is becoming more of a necessity. Standards poorly define how to manage OS as far as COTS is concerned, allowing for either excessively restrictive or permissive definitions of what is required. This paper proposes a methodology to isolate the safety-related service or program from failures of the COTS OS through design and detection techniques. The model argument presented, within the framework of the SIL based standards, justifies the use of Microsoft Windows OS (or equivalent) to enable safety-related functionality up to SIL 2.
An Improved Preamble Aided Preamble Structure Independent Coarse Timing Estimation Method for OFDM Signals

Timing estimation has been one of the major research issue in orthogonal frequency division multiplexing (OFDM) systems. In the literature there are mainly two types of preamble (data) aided timing estimation methods have been proposed. One type of timing estimation methods that depend on the specific structure of the preamble and the other type of timing estimation methods that work independent of the structure of the preamble. Performance of most of the timing estimation methods, which work independent of the structure of the preamble is severely affected in the presence of carrier frequency offset (CFO). The challenge is to design a preamble structure independent timing metric that should be robust to CFO. In this paper, a data aided coarse (initial) timing estimation scheme for OFDM system is proposed. Proposed timing estimation method is independent of the structure of the preamble and it works better than the other existing methods in the presence of CFO. The algorithm is also capable of using multiple preambles for coarse timing estimation. The performance is compared in terms of probability of erasure, probability of correct estimation and mean square error (MSE) with the existing timing synchronization methods for OFDM systems. Keywords—Timing synchronization; OFDM; Preamble; carrier frequency offset; Timing metric; MSE; Probability of erasure; Probability of correct estimation.
Screening and partial purification of photoprotective pigment scytonemin from cyanobacterial crusts dwelling on the historical monuments in and around Varanasi, India

In the present investigation, biological crusts from the surface of eight historical monuments of Varanasi, India, were examined for the presence of scytonemin (a cyanobacterial photoprotective pigment) containing cyanobacterial species. Lyngbya sp. and Scytonema sp. were the dominant cyanobacteria present in all crust samples. The absorption spectroscopic data of chlorophyll, carotenoids and scytonemin showed that scytonemin was more abundant than the carotene and chlorophyll in all the crusts. Identification of these compounds was done using UV-Vis spectroscopy and High Performance Liquid Chromatography (HPLC) analysis. HPLC analysis revealed the presence of scytonemin in seven out of eight samples and peaks of scytonemin with retention time ranging from 1.4-1.9 min with corresponding absorbance maxima at 386, 300 and 252±2 nm. As per our knowledge this is the first report of its kind from monuments of Varanasi. From this study, it can be concluded that synthesis of photoprotective compounds like scytonemin and its derivatives counteract the damaging effects of solar radiation which enable cyanobacteria to colonize and inhabit almost all kinds of habitats, including extreme lithic habitats, such as rocks and walls of monuments which face prolonged high intensity solar radiation.
Empirical Research on Information Transmission in the Hang Seng Index Markets: Evidence from Index Futures, Flagship Index and Finance Index

This paper investigates the price discovery mechanism in the Hang Seng Index markets. The analysis is based on the cross-market volatility spillover effects by using the daily sets of Hang Seng Index (HSI), Hang Seng Finance Index (HSFIN), and Hang Seng Index futures (HSCIS00). In order to testify the influence of 2007 financial tsunami on the volatility spillover effect, the study employs the vector autoregressive model (VAR) and the bivariate GARCH model based on the BEKK parameterization. The testing period has been divided into the pre-crisis (1 April, 2003 to 31 July, 2007) and the crisis & recovery period (1 August, 2007 to 1 April, 2013). The empirical results depict that there exists bi-directional volatility spillover effect between HSI and HSCIS00 for the whole testing period. In contrast, a strong bi-directional volatility spillover effect between HSFIN and HSCIS00 is only recognized after the outbreak of the 2007 financial crisis.
Conjecture Mapping the Library: Iterative Refinements Toward Supporting Maker Learning Activities in Small Community Spaces

A recent and important innovation in design-based research (DBR) is the use of conjecture maps, where researchers explicitly articulate the conjectured mediational relations between their designed goals and the learning designs and contexts. In this paper, we present a design case as an iterative sequence of evolving conjecture maps. As each conjecture map was tested, we revised it to highlight and refine our articulation of the tools and processes that embodied our design approach. Our design case involves small-town and rural community and school libraries in the United States as partners and DBR sites, with the goal of supporting librarians as they learn to develop and enact new STEM-oriented maker programs for youth. We show how conjecture mapping informed and supported our DBR work and how it helped push for specificity in hypothesized relations between the design, the learning setting, the outcomes, while also forcing a reflection on design constraints.
Beware the reformers: A Machiavellian view of the accounting profession and public sector reform in Australia

During the last two decades of New Public Management (NPM), reformist governments have transformed the principle underlying Australia’s government accountability from compliance to performance evaluation. This change has been instituted in three phases, against a backdrop of uncertainty, complexity, and the diverse interests of pressure groups. A Machiavellian interpretation of reform, focusing on resistance and power, proposes that the development of public sector accounting in Australia has been highly politicized and characterized by power battles between the accounting profession and government departments. This is illustrated by analyzing the process by which a policy for the valuation of public sector assets in Australia was developed. The result is that control over accounting standard setting has been wrested from the accounting profession by the government, using the adoption of international financial reporting standards as a catalyst for change, at the expense of professional and governmental accountability.
Adaptive Predictor for Entropy Coding

Abstract In this paper, an efficient predictor for entropy coding is proposed. It adaptively selects one of two prediction errors obtained by MED(median edge detector) or GAP(gradient adaptive prediction). The reduced error is encoded by existing entropy coding method. Experimental results show that the proposed algorithm can compress higher than existing predictive methods. 요 약 본 논문에서 엔트로피 코딩을 위한 효과적인 예측기를 제안한다 . 제안하는 예측기는 MED(median edge detector)와 GAP(gradient adaptive prediction)의 예측 에러 중의 하나를 적응적으로 선택한다. 감소한 에러는 기존의 엔트로피 코딩 방법을 이용하여 부호화한다. 실험 결과, 제안하는 알고리즘이 기존 예측 방법보다 향상된 압축이 가능함을 보인다. Key Words : Predictor, Entropy Coding, Lossless, Image Coding * Corresponding Author : Hyun-Sang Park(vandammm@kongju.ac.kr)Received October 1, 2009 Revised (1st December 11, 2009, 2nd December 20, 2009) Accepted January 20, 2010 1. Introduction Recently, many researches for image compression of digital images are increased. Especially, lossless compression is an important field of application for image compression. High-end digital devices enable the user to access the raw, uncompressed picture, i.e. not altered by any coding algorithm. Many algorithms were proposed. Context-based adaptive prediction schemes [1-5,7,8] have shown significant improvements over fixed prediction schemes. CALIC [1] uses gradient adaptive prediction (GAP). The new lossless compression standard JPEG-LS [2] adopts median edge detector (MED). A simple data prediction technique such as DPCM can de-correlate image data in smooth areas with very low computational cost. Prediction can be viewed as a context modeling technique of very low model cost that is highly effective under an assumption of smoothness. In JPEG-LS and CALIC, they chose to employ MED predictive coding and GAP predictive coding, respectively.In this paper, we propose an efficient technique called adaptive prediction algorithm which selects one of results obtained by the MED and GAP prediction, properly. Thus, it can reduce prediction error and obtain the reduced entropy of the residual error. Our proposed prediction method achieves good performance for entropy image coding and outperforms existing methods, such as MED and GAP, while having a low complexity.
Impact of Capturing Used Air on the Dynamics of Actuator Drive

This paper discusses the process of capturing the used air from the pneumatic actuator in a separate reservoir for its later use in order to get a higher energy efficiency of the pneumatic system. A mathematical model is developed and MATLAB simulations is performed. Certain conditions for collecting of air pressure under which the capturing can be used, without the loss of actuators dynamic characteristics, were determined by modeling and experimentally. A good correlation of results of modeling and the results obtained experimentally are shown.
A New Method of Grain Output Prediction Based on R/S Analysis

The grain production data series present some regularity and nonlinear characteristics in time. To overcome the shortcomings of the linear prediction low precision in traditional grain yield, the application of R/S analysis which based on the nonlinear fractal theory in grain output prediction is studied in this paper. Firstly, the hurst index of grain production series is calculated, thereby its average cycle is analyzed, finally, the prediction of grain production is obtained by the power value of grain production series. Simulation results have shown that the proposed method in this paper can realize the data prediction with nonlinear variation law, and has higher prediction accuracy, compared with the traditional grain output prediction method based on the arima model. Keywords-grain output, R/S analysis, prediction
A Cartesian model Model setup

This effort explores the fundamental dynamics of a solar model such as that of Gough and McIntyre[1]. The interaction of meridional flows downwelling from the convection zone into the radiative interior with a confined interior magnetic field is explored through a simple Cartesian model and linearized governing equations. Semianalytical solutions provide insight into these dynamics that have implications for magnetic confinement and gyroscopic pumping, as well as for stellar mixing.