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This paper aims to focus on the tracking of a moving magnetic target by using total field magnetometers and to present a tracking method based on the gradient of a magnetic anomaly. In the tracking, it is assumed that the motion of the target is equivalent to a first-order Markov process. And the unit direction vector of the magnetic moment from the gradient of the magnetic anomaly can be obtained. According to the unit direction vector, the inverse problem is turned into an optimization problem to estimate the parameters of the target. The particle swarm optimization algorithm is used to solve this optimization problem. The proposed method is validated by the numerical simulation and real data. The parameters of the target can be calculated rapidly using the proposed method. And the results show that the estimated parameters of the mobile target using the proposed method are very close to the true values.

The authors focus on the tracking of a moving magnetic target by using total field magnetometers and present a tracking method based on the gradient of a magnetic anomaly.

The paper provides an effective method for tracking the magnetic target based on an array with total field sensors.

Comparing with a vector magnetic sensor, the measurement of the scalar magnetic sensor is almost not influenced by its orientation. In this paper, a moving magnetic target was tracked by using total field magnetometers and a tracking method presented based on the gradient of a magnetic anomaly.

By applying Erving Goffman’s concept of role embracement (1961), I analyze the role of a hardcore music fan, online and offline. I collected ethnographic data from discussion boards, an online questionnaire, interviews, emails, private messaging, and field observation to provide support for the usefulness of Goffman’s concept to illuminate aspects of online and offline role performances. “Attachment,” “demonstration,” and “engagement” are the three elements of role embracement that illustrate aspects of the hardcore fan’s passion for the Rolling Stones, expressed both on the Internet and in everyday face-to-face situations. The study shows that Goffman’s ideas about a person’s commitment to a role and the handling of potential stigma (1963) in relation to it can help researchers understand how fans or those belonging to a special interest community enact their roles in the ever-growing seamlessness of the offline/online spheres.

The purpose of the current study is to profile Orlando and Florida culinary fans and compare them to culinary critics on several factors, including sociodemographics, psychographics, and travel behavior characteristics, and to identify potential factors that explain visitors' tendency to promote or criticize the cuisine of a destination. The study also seeks to identify the image attributes that explain the likelihood to visit for culinary fans and critics.

Online survey responses from 4,082 participants were analyzed using Qualtrics for survey design and Amazon's Mechanical Turk for data collection.

Demographic differences between culinary fans and critics were identified and significant relationships between perceptions of a destination's cuisine and various elements of the visitor experience were found.

The current study extends the literature on the characteristics of culinary tourists by showing a significant relationship between perceptions of a destination's cuisine and various elements of the visitor experience, such as destination image, satisfaction, number of past trips, and revisit intentions. Future studies should look at a greater number of distinct and geographically diverse destinations to test the generalizability of the current study's findings.

The results of this study provide implication for destination marketers in general and for those of Orlando and Florida in particular, especially in using cuisine as a potential core offering rather than a peripheral tourism product.

This study is believed to be the first to compare culinary fans and culinary critics, thereby extending the literature and demonstrating several differences between the two groups.

This study aims to examine foreign direct investment (FDI) factors and develops a rational framework for FDI inflow in Western European countries such as France, Germany, the Netherlands, Switzerland, Belgium and Austria.

Data for this study were collected from the World development indicators (WDI) database from 1995 to 2018. Factors such as economic growth, pollution, trade, domestic capital investment, gross value-added and the financial stability of the country that influence FDI decisions were selected through empirical literature. A framework was developed using interpretable machine learning (IML), decision trees and three-stage least squares simultaneous equation methods for FDI inflow in Western Europe.

The findings of this study show that there is a difference between the most important and trusted factors for FDI inflow. Additionally, this study shows that machine learning (ML) models can perform better than conventional linear regression models.

This research has several limitations. Ideally, classification accuracies should be higher, and the current scope of this research is limited to examining the performance of FDI determinants within Western Europe.

Through this framework, the national government can understand how investors make their capital allocation decisions in their country. The framework developed in this study can help policymakers better understand the rationality of FDI inflows.

An IML framework has not been developed in prior studies to analyze FDI inflows. Additionally, the author demonstrates the applicability of the IML framework for estimating FDI inflows in Western Europe.

This study aims to understand how the assembly of rotating ring affects the axial forced vibration of gas face seals.

A three-mass kinematic model is established to investigate the axial movement of the rotating ring with bilateral constraints. The separation, collision and frictional sliding of the rotating ring in sleeve are discussed under rotor excitation. The effects of operating parameters and O-ring dynamic characteristics on the separation degree and film thickness disturbance are analyzed. A dimensionless axial characteristic force is defined to determine the critical conditions for the occurrence of separation. Several effective methods to eliminate the separation are proposed based on the adjustment of typical installation parameters.

Under rotor excitation, there may be two collisions between the rotating ring and the sleeve surfaces in one excitation period. This will cause self-excited vibration of the fluid film, increasing the risk of seal failure. The separation and collision can be prevented by increasing the equilibrium ratio, the installation radius of the O-ring on the outer surface of the rotating ring and the friction in the sleeve.

The results develop the modeling of multibody dynamics of gas face seals, enabling more accurate prediction of vibration characteristics.

The case is set in Northeast Wisconsin, where the two largest industries are dairy farming and papermaking. Dairy farms have a continual need for bedding material for cows, and Lynn Heemeyer recognized an opportunity for a new bedding material: a waste byproduct of recycled paper. The case includes the progression of Heemeyer’s venture – Alternative Animal Bedding (AAB) – from the idea phase, to initiation and growth, to near collapse, recovery, and renewed growth. By September 2015, AAB was at a turning point as the sales were increasing, and Jess, Lynn’s daughter, had joined the business. Jess’s challenge: how best to grow the business.

Information for the case was gathered via interviews with Jess Heemeyer; she also provided some supporting materials. Jess Heemeyer is a former student of the author and a graduate of the institution that employs the author. Additional information for the case was collected from publicly available sources, as referenced. The identification of the college was not included in the case.

The case is best suited for use in an undergraduate or graduate entrepreneurship course or courses that include entrepreneurship as a topic. The case fits well with the topics of alertness and opportunity identification, and the innovation process. It can also be used to illustrate critical factors for new-venture development and growth. In addition, the benefits and challenges related to family-based entrepreneurial ventures can be included as a learning objective.

This case draws upon and illustrates the concept of alertness (Kirzner, 1973) which was further developed by Tang et al. (2012) when they identified three dimensions of alertness: “scanning and searching for information, connecting previously disparate information, and making evaluations on the existence of profitable business opportunities” (p. 77). Also, the case follows the creativity-based model of opportunity recognition developed by Corbett (2005) that uses experiential learning theory. Finally, students are asked to apply Ansoff’s Growth Matrix (Ansoff, 1957) to identify and evaluate the growth options available to the business owners and managers. As an optional pasture for discussion, a stewardship theory perspective can be applied to examine the family business aspect of this case (see Eddleston and Kellermanns, 2007).

Hydro-viscous drive (HVD) clutches are widely used in equipment requiring soft start, such as fans and pumps, to transmit torque and adjust speed by changing the gap distance between friction pairs. This paper aims to propose a novel two-parameter evaluation method for HVD during the mixed lubrication stage. The objective is to develop an effective model that establishes the relationship between these parameters and the actual surface topography.

In the presented methods, the fractal features of the real manufacturing surface are calculated based on the power spectrum function by the ultra-depth three-dimensional microscope. After that, the hybrid friction model of the friction plate is established based on mixed elasto-hydrodynamic lubrication theory, boundary friction model and fractal theory. Then the torque and load bearing characteristics of the clutch are obtained, and the influences of the surface fractal features are investigated and discussed. Finally, the Weierstrass–Mandelbrot function is adopted for the surface topography characterization and evaluation.

The results indicate that the proposed method exhibits good accuracy, while the speed difference between the friction pair exceeds 2,500 rpm. It is concluded that this paper proposed a way to evaluate the torque and loading capacity of HVD considering the real manufacturing surface topography and is helpful for surface optimization.

The originality and value of this study lie in its development of a novel torque and load bearing capacity evaluation method for HVD in mixed lubrication stage, considering manufacturing surface topography and describing the real manufacturing surface.

AXIAL flow fans were originally developed from aircraft airscrews and therefore can be claimed as children of aeronautical science. Their use has been confined in aeronautics to wind tunnels and radial engine cooling until the advent of ‘pressurized’ cabins. In this case ventilation requirements have caused an axial flow fan to be used. These fans have been gradually developed in the ventilation industry and they are replacing centrifugal fans where these would have been used previously. Price and noise level have not been in the axial flow fans' favour in this fight but they have advantages of higher efficiency, ease of installation and non‐overloading power characteristic. Latest developments in aerodynamic design and production technique suggest that the disadvantages are being overcome. This note is intended to furnish a general introduction to the design features of axial flow fans for aircraft ventilation.

Heat also facilitates the transmission of water through the cell walls, thereby assisting its passage from the interior to the surface of the material; it increases the vapour pressure of water, thus increasing its tendency to evaporate; and it increases the water‐vapour‐carrying capacity of the air. In the United States the unit of heat customarily used is the British thermal unit (B.t.u.), which for practical purposes is defined as the heat required to raise the temperature of a pound of water 1° F. Heat is commonly produced through the combustion of oil, coal, wood, or gas. Heating by electricity is seldom practicable because of its greater cost; but where cheap rates prevail it is one of the safest and most efficient, convenient and easily regulated methods. Direct heat, direct radiation and indirect radiation are the types of heat generally employed. Direct‐heating systems have the highest fuel or thermal efficiency. The mixture of fuel gases and air in the combustion chamber passes directly into the air used for drying. This method requires the use of special burners and a fuel, such as distillate or gas, which burns rapidly and completely, without producing soot or noxious fumes. The heater consists simply of a bare, open firebox, equipped with one or more burners, an emergency flue to discharge the smoke incidental to lighting, and a main flue, through which the gases of combustion are discharged into the air duct leading to the drying chamber. Direct‐radiation systems also are relatively simple and inexpensive and have a fairly high thermal efficiency. A typical installation consists of a brick combustion chamber with multiple flues, which carry the hot gases of combustion back and forth across the air‐heating chamber and out to a stack. The air is circulated over these flues and heated by radiation from them. The flues are made of light cast iron or sheet iron. The air‐heating chamber should be constructed of fireproof materials. The efficiency of the installation depends upon proper provision for radiation. This is attained by using flues of such length and diameter that the stack temperatures will be as low as is consistent with adequate draught. Heating the air by boiler and steam coils or radiators is an indirect‐radiation system, as the heat is transferred from the fuel to the air through the intermediate agency of steam. Such a system costs more to install and has a lower thermal efficiency than either of the other two systems. It is principally adapted to large plants operating over a comparatively long season on a variety of materials where the steam is needed to run auxiliary machinery or to process vegetables. Large volumes of air are required to carry to the products the heat needed for evaporation and to carry away the evaporated moisture. Insufficient air circulation is one of the main causes of failure in many dehydrators, and a lack of uniformity in the air flow results in uneven and inefficient drying. The fan may be installed to draw the air from the heaters and blow it through the drying chamber, or it may be placed in the return air duct to exhaust the air from the chamber. An advantage of the first installation is that the air from the heaters is thoroughly mixed before it enters the drying chamber. It has been claimed that exhausting the air from the chamber increases the rate of drying by reducing the pressure, but the difference is imperceptible in practice. Either location for the fan is satisfactory, and the chief consideration in any installation should be convenience. Close contact between the air and the heaters and between the air and the material is necessary for efficient transfer of heat to the air and from the air to the material, and to carry away the moisture. The increased pressure or resistance against which the fan must operate because of such contact is unavoidable and must be provided for, but at other points in the system every effort should be made to reduce friction. To this end air passages should be large, free from constrictions, and as short and straight as possible. Turns in direction should be on curves of such diameter as will allow the air to be diverted with the least friction. The general rule in handling air is that a curved duct should have an inside radius equal to three times its diameter. The water vapour present in air at ordinary pressures is most conveniently expressed in terms of percentage of relative humidity. Relative humidity is the ratio of the weight of water vapour actually present in a space to the weight the same space at the same temperature would hold if it were saturated. Since the weight of water vapour present at saturation for all temperatures here used is known, the actual weight present under different degrees of partial saturation is readily calculated from the relative humidity. Relative humidity is determined by means of two thermometers, one having its bulb dry and the other having its bulb closely covered by a silk or muslin gauze kept moist by distilled water. Tap water should not be used because the mineral deposits from it clog the wick, retard evaporation, and produce inaccurate readings. The wick must be kept clean and free from dirt and impurities. The two thermometers are either whirled rapidly in a sling or used as a hygrometer mounted on a panel with the wick dipping in a tube of water and the bulbs exposed to a rapid and direct current of air. The relative humidities corresponding to different wet‐ and dry‐bulb temperatures are ascertained from charts furnished by the instrument makers, or published in engineers' handbooks. As a general rule, the more rapidly the products have been dried the better their quality, provided that the drying temperatures used have not injured them. Some fruits and vegetables are more susceptible to heat injury than others, but all are injured by even short exposures to high temperatures. The duration of the exposure at any temperature is important, since injury can be caused by prolonged exposure at comparatively moderate temperatures. The rate of evaporation from a free water surface increases with the temperature and decreases with the increase of relative humidity of the air.

The analyses of trends in prosecutions under the Food and Drugs Act, 1955 and the various regulations, which we have prepared every two years or so, covering a three‐month period, have been so much appreciated by readers, both in the administration and the industry itself, that we have prepared a more extended survey, covering the whole of 1966. The survey, as before, takes the form of a month‐by‐month analysis of reports of legal proceedings received by us from all parts of the country, and as formerly records the prosecutions under similar groupings; cases under Section 2, subdivided into those relating to compositional offences, the presence of foreign bodies and those relating to mouldy food: false description cases under Section 6 of the Merchandise Marks Acts; Section 8, the unfit food provision, also subdivided with special categories for foreign bodies and mouldy food; Section 32, milk cases; cases under the Food Hygiene Regulations, 1960, with smoking offences separated; the Milk and Dairies Regulations, consisting almost entirely of prosecutions under Reg. 27, Meat Regulations, Preservative Regulations, Colouring Matter in Food Regulations, etc.