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The paper introduces and illustrates the use of numerical models for the simulation of electromagnetic and thermal processes in an absorbing ceramic layer (susceptor) of a new millimeter-wave (MMW) heat exchanger. The purpose of this study is to better understand interaction between the MMW field and the susceptor, choose the composition of the ceramic material and help design the physical prototype of the device.

A simplified version of the heat exchanger comprises a rectangular block of an aluminum nitride (AlN) doped with molybdenum (Mo) that is backed by a thin metal plate and irradiated by a plane MMW. The coupled electromagnetic-thermal problem is solved by the finite-difference time-domain (FDTD) technique implemented in QuickWave. The FDTD model is verified by solving the related electromagnetic problem by the finite element simulator COMSOL Multiphysics. The computation of dissipated power and temperature is based on experimental data on temperature-dependent dielectric constant, loss factor, specific heat and thermal conductivity of the AlN:Mo composite. The non-uniformity of patterns of dissipated power and temperature is quantified via standard-deviation-based metrics.

It is shown that with the power density of the plane wave on the block’s front face of 1.0 W/mm², at 95 GHz, 10 × 10 × 10-mm blocks with Mo = 0.25 – 4% can be heated up to 1,000 °C for 60-100 s depending on Mo content. The uniformity of the temperature field is exceptionally high – in the course of the heating, temperature is evenly distributed through the entire volume and, in particular, on the back surface of the block. The composite producing the highest level of total dissipated power is found to have Mo concentration of approximately 3%.

In the electromagnetic model, the heating of the AlN:Mo samples is characterized by the volumetric patterns of density of dissipated power for the dielectric constant and the loss factor corresponding to different temperatures of the process. The coupled model is run as an iterative procedure in which electromagnetic and thermal material parameters are upgraded in every cell after each heating time step; the process is then represented by a series of thermal patterns showing time evolution of the temperature field.

Determination of practical dimensions of the MMW heat exchanger and identification of material composition of the susceptor that make operations of the device energy efficient in the required temperature regime require and expensive experimentation. Measurement of heat distribution on the ceramic-metal interface is a practically challenging task. The reported model is meant to be a tool assisting in development of the concept and supporting system design of the new MMW heat exchanger.

While exploitation of a finite element model (e.g. in COMSOL Multiphysics environment) of the scenario in question would require excessive computational resources, the reported FDTD model shows operational capabilities of solving the coupled problem in the temperature range from 20°C to 1,000°C within a few hours on a Windows 10 workstation. The model is open for further development to serve in the ongoing support of the system design aiming to ease the related experimental studies.

Recommendation systems are a fundamental tool for hotels to adopt a differentiating competitive strategy. The main purpose of this work is to use machine learning techniques to treat imbalanced data sets, not applied until now in the tourism field. These techniques have allowed the authors to analyse the influence of imbalance data on hotel recommendation models and how this phenomenon affects client dissatisfaction.

An opinion survey was conducted among hotel customers of different categories in 120 different countries. A total of 135.102 surveys were collected over eleven quarters. A longitudinal design was conducted during this period. A binary logistic model was applied using the function generalized lineal model (GLM).

Through the analysis of a representative amount of data, the authors empirically demonstrate that the imbalance phenomenon is systematically present in hotel recommendation surveys. In addition, the authors show that the imbalance exists independently of the period in which the survey is done, which means that it is intrinsic to recommendation surveys on this topic. The authors demonstrate the improvement of recommendation systems highlighting the presence of imbalance data and consequences for marketing strategies.

The main contribution of the current work is to apply to the tourism sector the framework for imbalanced data, typically used in the machine learning, improving predictive models.

Performance feedback about whether responses are correct or incorrect provides valuable information to help guide learning. Although feedback itself has no extrinsic value, it can produce subjective feelings similar to “rewards” and “punishments.” Therefore, feedback can play both an informative and a motivational role. Over the past decade, researchers have identified a neural circuit that processes reward value and promotes reinforcement learning, involving target regions of dopaminergic input (e.g., striatum and ventromedial prefrontal cortex). Importantly, this circuit is engaged by performance feedback even in the absence of reward. Recent research suggests that feedback-related brain activity can be modulated by motivational context, such as whether feedback reflects goal achievement, whether learners are oriented toward the informative versus evaluative aspect of feedback, and whether individual learners are motivated to perform well relative to their peers. This body of research suggests that the brain responds flexibly to feedback, based on the learner’s goals.

The purpose of this paper is to investigate the structure and electrical properties of eutectic Sb_7.4Te_92.6 as made thin films to evaluate their potentiality for application to non-volatile phase-change memories.

The films were prepared by the pulsed laser deposition technique. The films were characterized by using X-ray diffraction in grazing-incident geometry, differential scanning calorimetry, Raman spectroscopy and transversal current–voltage curves.

The memory effect state, characteristic of a typical phase-change memory material, was observed. The temperature of crystallization was about 100ºC.

Further studies on endurance, scaling and SET/RESET operations are needed.

One of the main characteristic values, the hold voltage and the threshold voltage values, were about 0.85 and 1.2 V, respectively, in a line with those of Ge₂Sb₂Te₅, GeTe and Sb₂Te being considered to date as the main compounds for phase-change memory devices.

The conduction mechanism in the amorphous regime is highly agreed with the Poole–Frenkel effect in deep traps.

The purpose of this research was to investigate the effects of patriotism and identification with national players on identification with the NBA and, ultimately, with purchase intentions of league-related merchandise. Findings revealed that the interaction between patriotism and identification with national players was a significant predictor of identification with NBA, which in turn was a significant predictor of purchase intentions of league-related products. The moderated mediation model fit the data quite well and explained 44.5% of the variance in purchase intentions. Theoretical implications of the findings, as well as practical implications for sports managers, are discussed.

In commenting upon a recent action brought by a Mr. Soper for a libel published upon him in a trade journal in regard to the sale of adulterated boots, the Daily Telegraph makes some excellent remarks, which ought to appeal strongly to all manufacturers, no matter what trade they are engaged in, who are really desirous of conducting their concerns upon honest and straightforward lines. The Daily Telegraph observes that reformers are rarely popular with their rivals, especially when they expose tricks in the trade, and advocate raising the standard of commercial honesty. Mr. Soper, the plaintiff in the case in question, was in that position. He had started a crusade against the practice of adulterating the soles of boots with paper fillings, and advocated a standard mark, in order to distinguish what is genuine from what is adulterated. This was resented by the threatened interests. Mr. Soper raised up enemies, and, in consequence, the article complained of was written, accusing him of “knowingly” selling adulterated boots at his shop while he thus publicly denounced them. The libel lay in the word “knowingly,” for it appeared that adulterated boots were actually sold at Mr. SoPer's establishment. But this was because he had failed to detect their presence; he had taken all the precautions which he could take, and he had cut open a number of pairs; he demanded guarantees from the manufacturers with whom he dealt; and, moreover, he was willing to take back any pair from any customer which were found to contain paper. The boot trade does not emerge with credit from this investigation. It was admitted that adulteration had been going on for the last ten years, and one manufacturer's traveller, when asked whether he was not surprised that paper should be found in the soles of boots costing seven or eight shillings, frankly replied, “Nothing surprises me in the boot trade.” The public will share his truly Horatian attitude of mind. Some such standard mark as that advocated by Mr. Soper seems to be the only method of protecting the public, if, indeed, the public desires to be protected, which seems doubtful. The ordinary customer is as helpless in a boot shop as in a curiosity shop. He must trust the word of the shopkeeper. And in turn the shopkeeper has to trust the manufacturers. The excuses of some of the latter, that the use of paper instead of leather did not mean any profit for them, or that the workmen could not be stopped from using cardboard fillings, will not do. There would be no adulteration if it were not profitable to adulterate. Adulteration seems to be rampant in most industries. One might even say that in some it is no longer the exception, but the rule. Wool, for example, has been treated just as scurvily as leather. Woollen no longer means woollen, but cotton with a pinch of wool. One has to ask for “guaranteed pure wool”— and pay accordingly—to feel any confidence that one is getting wool. So, too, with flannel and silk, and even cotton is adulterated with minerals to give it an essentially false weight. The ingredients from which “shoddy” is made would terrify the future wearer of it if he could see the “devil” at work, tearing up the noisome rags. Ignorance in this respect is becoming more blissful every year. Cheap sweets, cheap jams, cheap table delicacies, and all kinds of foods, all of which are warranted pure by the manufacturers, are, as a matter of fact, adulterated with impunity, and are all, in reality, “nasty” as well as “cheap.” The impotence of Government departments and of the Legislature in face of this condition of things has been demonstrated ad nauseam, and while such efforts as are made by local authorities to detect and suppress adulteration should receive all possible support and encouragement, it must be admitted that there is only one effective way of dealing with the evil—namely, the supply of guarantees of an independent and authoritative type to retail vendors and purchasers.

While literature has examined market orientation, it is limited with respect to small businesses. More specifically, previous research has not considered empirically the relationship between small business market orientation and environmental uncertainty. Due to resource constraints, smaller businesses are especially vulnerable to environmental uncertainty. To address this, the purpose of this paper is to examine the relationship between environmental uncertainty and small business market orientation.

Drawing from small business literature, the authors developed a research model advancing and testing hypotheses to address the research aim. An empirical study was conducted with 104 small grocery retailers from Brazil. A questionnaire was administered, divided into two sections relating to measurement of market orientation and the market turbulence and technological turbulence as dimensions of environmental uncertainty. ANOVA technique and a multinominal logistic regression model were employed to analyze the results.

The findings reinforce the view of market orientation as a dynamic construct which can explain the relationship between small businesses and environmental uncertainty. Small businesses with higher levels of market orientation emphasized responsiveness as a critical dimension in orienting to turbulent markets. The findings also show that aspects of technological turbulence, particularly pertaining to the opportunities for competitive advantage and new ideas for product supply related to higher levels of market orientation.

The paper's findings, addressing a knowledge gap in the small business literature, emphasize the importance of small businesses orienting themselves to the market, particularly in environments characterized by higher levels of market and technological turbulence.

Because I want the next generation of women to be set free from the birdcage of racial, gender and class stereotypes, a place from which my mother, grandmothers and great grandmothers never had the chance to escape, it is a personal and political choice to rupture the experiences of racial prejudice that bind us into phobic races within various shades of hatred. I am both digging a new place to find “truth” and criticizing an essential part of who I am or what I was taught to believe about our black and indigenous heritage. An epiphanic moment combines past, present and future moments into an act of doing and becoming. In honoring the first “queen” in my family, I wrote the following non-fiction children's story about my great grandmother Bernarda in three languages. Although I have never seen a picture of Bernarda, I feel her Chibcha blood burning inside of me and within every awkward phrase that I piece together as I fumble through grammatical structures, reviving memories into performative language. I wrote the first draft in English and later translated it into French and Spanish.

This work provides a generic review of the existing data mining ontologies (DMOs) and also provides a base platform for ontology developers and researchers for gauging the ontologies for satisfactory coverage and usage.

The study uses a systematic literature review approach to identify 35 DMOs in the domain between the years 2003 and 2021. Various parameters, like purpose, design methodology, operations used, language representation, etc. are available in the literature to review ontologies. Accompanying the existing parameters, a few parameters, like semantic reasoner used, knowledge representation formalism was added and a list of 20 parameters was prepared. It was then segregated into two groups as generic parameters and core parameters to review DMOs.

It was observed that among the 35 papers under the study, 26 papers were published between the years 2006 and 2016. Larisa Soldatova, Saso Dzeroski and Pance Panov were the most productive authors of these DMO-related publications. The ontological review indicated that most of the DMOs were domain and task ontologies. Majority of ontologies were formal, modular and represented using web ontology language (OWL). The data revealed that Ontology development 101, METHONTOLOGY was the preferred design methodology, and application-based approaches were preferred for evaluation. It was also observed that around eight ontologies were accessible, and among them, three were available in ontology libraries as well. The most reused ontologies were OntoDM, BFO, OBO-RO, OBI, IAO, OntoDT, SWO and DMOP. The most preferred ontology editor was Protégé, whereas the most used semantic reasoner was Pellet. Even ontology metrics for 16 DMOs were also available.

This paper carries out a basic level review of DMOs employing a parametric approach, which makes this study the first of a kind for the review of DMOs.

The access to the rare originals of the early Spanish colonial imprints of the Philippines remains problematic. The reference librarians often are restricted to directing the students and scholars to the secondary resources that are available both in print and as a part of the digital assets within the North American academic libraries. This paper aims to focus on the select primary source editions including select Spanish language colonial imprints that are available electronically on the Web along the Open Access. These Web-based resources serve as the reference tools for the early history of the Philippines and Southeast Asia. As many of these publications are rare and extremely expensive for most libraries, the Open Access resources serve as an aid to building a virtual collection of these items.

The author had to create a data set of the early imprints of the Spanish Philippines using several bibliographic resources. The data set will be submitted as an Appendix for this research paper. The author did both qualitative and quantitative analysis of the data set along with the voyant-based digital humanities approach for topic modeling.

The goals of this paper were to not only survey the early Spanish printing of the Philippines but also provide the reader with a somewhat complete picture of how the printing began in the Spanish Philippines, what kind of the first books were printed and how one can access them given their rarity and fragility. The collection building paradigms are undergoing significant shifts, and the focus of many academic libraries is shifting toward providing access to these items. As these items high-value low-use items continue to be part of the Special Collections, the access to these is problematic. The virtual collections thus serve as a viable alternative that enables further research and access. While the creators of these works are long gone, the legacy of the Spanish colonial domination, printing and the religious orders in the Philippines remain alive through these works.

As this is an introductory paper, the author focused on the critical editions rather than providing a comprehensive bibliographic landscape of the presses that produced these editions. He also did not take into consideration many pamphlets that were published in the same period. He also did not consider the Chinese language publications of the Islands. The Chinese had been block printing since medieval times (Little, 1996). In the context of the Spanish Philippines, the Chinese migration and trade have been studied in detail by Chia (2006), Bjork (1998) and Gebhardt (2017). The scope of this paper also was centered toward building a virtual collection of these rare books.

Rare books are often expensive and out-of-reach for many libraries; the virtual collection of the same along the Open Access model represents an alternative to collect and curate these collections. The stewardship of these collections also acquires a new meaning in the digital milieu.

This research paper will allow scholars to see past the analog editions and help them focus on curating a virtual collection. The questions of electronic access are often ignored when it comes to visiting and using them in a controlled environment of the reading room in the Special Collections. The author argues that one way to enable access to these rare and expensive books is to provide access to their digital counterparts. These digital/virtual surrogates of the originals will facilitate further research.

The author could not find similar research on the publications of the early Spanish colony of the Philippines.