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This study seeks to explore the aerodynamic performance of wings with different shapes at low Reynolds numbers.

The airfoils of these wings are made from aluminum plates, and the maximum cord length and wingspan are 15 cm. Wings A to D are plates with 6 percent Gottingen camber but different wing planforms. The forward‐half sections of wings E and F are dragonfly‐like, whereas the rear‐half sections of wings E and F are flat and positively cambered, respectively. The aspect ratios of these wings are close to one, and the ratios of plate thickness to the maximum cord length are 1.3 percent. Experimental results indicate that the wings with Gottingen camber have a superior lift and lift‐to‐drag ratio, whereas the wings with dragonfly‐like airfoils perform well in terms of drag and pitch moment.

The aerodynamic measurements of the wings demonstrate that the wing with the Gottingen camber airfoil, a swept‐back leading edge and a straight trailing edge is suitable for use in micro aerial vehicle (MAV). An MAV is fabricated with this wing and the aerodynamic performance of the MAV is examined and compared with the bare wing data.

This study develops several criteria to the design of MAV‐sized wings. For example, the thickness ratio of airfoil must be small, usually less than 2 percent. Besides, the airfoil must be cambered adequately. Furthermore, a wing planform with a swept‐back leading edge and a straight trailing edge would be contributive to the successful flights of MAVs.

With aims to increase the aerodynamic efficiency of aerodynamic surfaces, study on flow control over these surfaces has gained importance. With the addition of flow control devices such as synthetic jets and vortex generators, the flow characteristics can be modified over the surface and, at the same time, enhance the performance of the body. One such flow control device is the tubercle. Inspired by the humpback whale’s flippers, these leading-edge serrations have improved the aerodynamic efficiency and the lift characteristics of airfoils and wings. This paper aims to discusses in detail the flow physics associated with tubercles and their effect on swept wings.

This study involves a series of experimental and numerical analyses that have been performed on four different wing configurations, with four different sweep angles corresponding to 0°, 10°, 20° and 30° at a low Reynolds number corresponding to Re_c=100,000.

Results indicate that the effect of tubercles diminishes with an increase in wing sweep. A significant performance enhancement was observed in the stall and post-stall regions. The addition of tubercles led to a smooth post-stall lift characteristic compared to the sudden loss in the lift with regular wings. Among the four different wings under observation, it was found that tubercles were most effective on the 0° configuration (no sweep), showing a 10.8% increment in maximum lift and a 38.5% increase in the average lift generated in the post-stall region. Tubercles were least effective on 30° configuration. Furthermore, with an increase in wing sweep, co-rotating vortices were distinctly observed rather than counter-rotating vortices.

While extensive numerical and experimental studies have been performed on straight wings with tubercles, studies on the tubercle effect on swept wings at low Reynolds number are minimal and mainly experimental in nature. This study uses numerical methods to explore the complex flow physics associated with tubercles and their implementation on swept wings. This study can be used as an introductory study to implement passive flow control devices in the low Reynolds number regime.

The purpose of this paper is to explore the social climate of therapeutic wings and mainstream wings within one prison, to identify positive areas of social climate that can be built upon and areas for improvement.

In total, 1,054 social climate questionnaires (the Essen Climate Evaluation Schema – EssenCES) were sent to prisoner-facing staff and all prisoners within an English Category B prison holding indeterminate sentenced prisoners. Perceptions of social climate on therapeutic wings and mainstream wings and perceptions of social climate between staff and prisoners were compared.

The results showed that the therapeutic wings felt safer, there were better staff-prisoner relationships and there was better peer support among prisoners than people on the mainstream wings. Also, prisoners felt safer than staff, staff rated the overall social climate as more positive than prisoners and staff felt that they supported prisoners, but prisoners did not feel the same.

The main limitation is that the EssenCES measure does not explain the participants’ ratings of the social climate.

There is a need to transfer the principles and values of therapeutic wings to mainstream wings. In addition, there is significant room for improvement in the social climate of this prison.

This is the first study to compare the social climate of therapeutic and mainstream wings within one single prison. The research has a valuable contribution to the development of positive social climates conducive to better clinical outcomes.

THE change from the parallel wings of the now obsolescent biplane to the tapered wings of the monoplane, usually fitted with flaps, raised a great number of problems, both aerodynamic and structural. Work on these has been pursued vigorously during the past few years, but the designer is still some considerable distance from having all his questions answered. For instance, further information is required as to the relation between wing thickness and profile drag before it can be decided what is the maximum thickness which can be used, taking both aero‐dynamical and structural considerations into account. This question is complicated by the fact that, so far as the tip sections are concerned,. the indications are that the thickness ratio has important effects on the nature of the stall, violent or gentle. So, too, will such factors as centre line camber and position of maximum ordinate affect the nature of the stall in greater or Jess degree. Added to these factors there is, of course, the important one of the taper itself, including—as is now realised—the question as to the way in which the tapering is done, that is, whether by sweeping the trailing edge forward or the leading edge back, or, as is more usual, a combination of the two.

This study aims to analyze prisoners’ experiences of prison drug-treatment programs in Sweden. How do they describe their personal relationships with the prison staff and with other prisoners in the wings? How do they describe the social climate and the control in drug-treatment wings? How could differences between these wings be understood?

The data consist of observations and face-to-face interviews with male and female prisoners in three Swedish prison drug-treatment wings. Analytical concepts used are roles, relationships and rituals.

The prisoners’ relationships with prison officers seemed connected to what kinds of rituals the prisoners and staff engaged in. In all three treatment wings, the staff and prisoners were involved in natural rituals. This was most frequent in the women’s prison with a 12-step program. The prisoners were frustrated with control measures but were mainly positive to the measures as preventing drugs from coming into the wing.

Only three prison wings, however in varying prisons, have been studied.

These results gives a useful prisoners’ perspective on the development of drug-prevention and treatment in different kinds of prisons.

The purpose of this exhaustive experimental study is to investigate the fluid-structure interaction in the flexible membrane wings over a range of angles of attack for various Reynolds numbers.

In this paper, an experimental study on fluid-structure interaction of flexible membrane wings was presented at Reynolds numbers of 2.5 × 10⁴, 5 × 10⁴ and 7.5 × 10⁴. In the experimental studies, flow visualization, velocity and deformation measurements for flexible membrane wings were performed by the smoke-wire technique, multichannel constant temperature anemometer and digital image correlation system, respectively. All experimental results were combined and fluid-structure interaction was discussed.

In the flexible wings with the higher aspect ratio, higher vibration modes were noticed because the leading-edge separation was dominant at lower angles of attack. As both Reynolds number and the aspect ratio increased, the maximum membrane deformations increased and the vibrations became visible, secondary vibration modes were observed with growing the leading-edge vortices at moderate angles of attack. Moreover, in the graphs of the spectral analysis of the membrane displacement and the velocity; the dominant frequencies coincided because of the interaction of the flow over the wings and the membrane deformations.

Unlike available literature, obtained results were presented comparatively using the sketches of the smoke-wire photographs with deformation measurement or turbulence statistics from the velocity measurements. In this study, fluid-structure interaction and leading-edge vortices of membrane wings were investigated in detail with increasing both Reynolds number and the aspect ratio.

Recovery is the predominant discourse within current UK drug policy, promoted as freedom from dependence. In support of such a policy driver, prison drug recovery wings have been piloted in ten prisons in England and Wales to address high drug prevalence rates in prisoner populations. The purpose of this paper is to explore the development of these specialist wings within the context of wider developments to tackle reoffending among drug-using prisoners.

The first part of the paper offers an analysis of the emergence of the recovery paradigm in the prison context through analysis of official policy documents. The second draws predominantly upon two process evaluations of the drug recovery wings, alongside literature on prison drug treatment.

There is limited empirical evidence to inform the debate about whether prisons can provide settings to facilitate recovery from the effects of illicit drug use. What is available suggests that effective therapeutic environments for recovering drug users could be established within prisons. Key components for these appear to be sufficient numbers of staff who are competent and confident in providing a dual role of support and discipline, and a common purpose of all prisoners committing to recovery from illicit drugs and supporting each other. Further research regarding the impact of drug recovery wings upon health, crime and wider social outcomes is needed.

This paper provides an updated perspective on the development of drug treatment in prisons, with a particular focus on the implications of the new recovery paradigm.

The purpose of this paper is to consider divergence of composite plate wings as well as slender wings with thin-walled cross-section of small-size airplanes. The main attention is paid to establishing of closed-form mathematical solutions for models of wings with coupling effects. Simplified solutions for calculating the divergence speed of wings with different geometry are established.

The wings are modeled as anisotropic plate elements and thin-walled beams with closed cross-section. Two-dimensional plate-like models are applied to analysis and design problems for wings of large aspect ratio.

At first, the equations of elastic deformation for anisotropic slender, plate-like wing with the large aspect ratio are studied. The principal consideration is delivered to the coupled torsion-bending effects. The influence of anisotropic tailoring on the critical divergence speed of the wing is examined in closed form. At second, the method is extended to study the behavior of the large aspect ratio, anisotropic wing with box-like wings. The static equations of the wing with box-like profile are derived using the theory of anisotropic thin-walled beams with closed cross-section. The solutions for forward-swept wing with box-like profiles are given in analytical formulas. The formulas for critical divergence speed demonstrate the dependency upon cross-sectional shape characteristics and anisotropic properties of the wing.

The following simplifications are used: the simplified aerodynamic theory for the wings of large aspect ratio was applied; the static aeroelastic instability is considered (divergence); according to standard component methodology, only the component of wing was modeled, but not the whole aircraft; the simplified theories (plate-lime model for flat section or thin-walled beam of closed-section) were applied; and a single parameter that defines the rotation of a stack of single layers over the face of the wing.

The simple, closed-form formulas for an estimation of critical static divergence are derived. The formulas are intended for use in designing of sport aircraft, gliders and small unmanned aircraft (drones). No complex analysis of airflow and advanced structural and aerodynamic models is necessary. The expression for chord length over the span of the wing allows for accounting a board class of wing shapes.

The derived theory facilitates the use of composite materials for popular small-size aircraft, and particularly, for drones and gliders.

The closed-form solutions for thin-walled beams in steady gas flow are delivered in closed form. The explicit formulas for slender wings with variable chord and stiffness along the wing span are derived.

Wings Academy is a charter school¹ in Milwaukee, Wisconsin that opened in August of 2002. It is located in the basement of an enormous, beautifully decorated and well maintained convent which houses several social service agencies, retired School Sisters who live there and another charter school. This school was envisioned and created by the authors (Co-Directors), two special education teachers (one is also a parent of a child with Asperger’s Syndrome) who believed the local districts were not providing an appropriate education for students with special education needs, and those with a label of “learning disabled” in particular. Prior to meeting, the Co-Directors had thoughts of creating their own Utopian school in which all students were taught with appropriate methodologies. By the time they had met, they both knew what their school would look like. Eventually, they combined their ideas and opened a school three years later. In this chapter, they describe the rationale for this school and programmatic realities that they have adapted to achieve their vision.

This study aims to investigate the effectiveness of two types of winglets, multi-tip and raked, on the performance of sinusoidal and simple leading-edge wings and compares it by a numerical method.

The wing configuration in this study is rectangular and uses NACA0020 section, and all simulations are performed by a numerical method based on finite volume and base pressure algorithm in Reynolds 2 × [10]^5. In the mentioned numerical method, the flow is considered turbulent, and the k-ω-SST model is used. To calculate the stresses on the wing surface, the mesh is extended to below the viscous layer, and a second-order upstream accuracy is used to calculate the convection flux.

The use of raked and multi-tip winglets for the sinusoidal edge of the wing improved aerodynamic performance by 5.12 and 2.28%, respectively, and the greatest effect of these two winglets was on increasing the lifting force and reducing the inductive drag, respectively. Also, by examining the distribution of induced vortices around the configurations, it was found that the curvature of the sinusoidal wing tip at the angles of attack before stall reduced the strength of the induced vortices and, the use of winglet during and after stall, caused increased aerodynamic performance of the sinusoidal wing.

The whale is an international species of aquatic animal found in most of the world’s oceans. It has large fin aspect ratios that have a series of bulges at the edge of the attack, which improves the aerodynamic performance near and after stall. Today, one of the fields of research is the use of this idea in the wings of micro air vehicle.

Winglet reduces induced drag in simple wings. So far, the effect of winglets on wings with sinusoidal attack edges has not been investigated.