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In recent years, increased use of all-aspect infrared (IR)-guided missiles based on the long-wave infrared (LWIR; 8–12 µm) band has lowered the probability of aircraft survival in warfare. The lock-on of these highly sensitive missiles is difficult to break, especially from the front. Aerodynamically heated swept-back leading edges (SBLE), because of their high temperature and large area, serve as a prominent LWIR source for aircraft detection from the front. This study aims to report the influence of sweep-back angle (Λ, based on the Mach number [M_∞]) on aerodynamic heating and the LWIR signature of SBLE.

The temperature along SBLE is obtained numerically as radiation equilibrium temperature (T_w) by discretizing the SBLE length into “n” number of segments, and for each segment, emission based on T_w is evaluated. IR radiance due to reflected external sources (sky-shine and Earthshine) and radiance due to T_w are collectively used to determine the IR contrast between SBLE and its replaced background in the LWIR band (i_{cont-SBLE,LWIR}).

The results are obtained for low subsonic turboprop aircraft (Λ = 3°, M_∞ = 0.44); high subsonic strategic bombers (Λ = 35°, M_∞ = 0.8); fifth-generation stealth aircraft (Λ = 40°, M_∞ = 1.6); and aircraft with supercruise/supersonic capability (Λ = 50°, M_∞ = 2.5). The aircraft with supersonic capability (Λ = 50°, M_∞ = 2.5) reports the maximum LWIR signatures and hence the highest visibility from the front. The results obtained are compared with values at Λ = 0° for all cases, which shows that increasing Λ significantly reduces aerodynamic heating and LWIR signatures.

The novelty of this study comes from its report on the influence of Λ on the LWIR signatures of aircraft SBLE in the frontal aspect for the first time.

As real‐time, high‐fidelity visual scene simulation has become ubiquitous in the training, modeling and simulation community, a growing need for more than “out‐the‐window” scene simulation has developed. A strong requirement has developed for the ability to simulate the output of different types of sensors, especially electro‐optical (EO), infrared (IR), night vision goggle (NVG) and radar systems. To satisfy the need for advanced sensor simulation, Evans & Sutherland (E&S) has developed a physics‐based, dynamic, real‐time sensor simulation which allows users to model advanced EO, IR and NVG devices that are fully correlated with the “out‐the‐window” visual view. In this paper, the unique sensor simulation capabilities of E&S will be described. A brief description of the physics employed, input and output are presented along with example images.

DO THE GIRLS of the Mary Erskine School in Edinburgh remember that the teaching staff once included—in the days when it was known at Queen Street Ladies' College—a writer of considerable distinction? James Logie Robertson was his name, but his works appeared with the pen‐name ‘Hugh Haliburton’.

Entrepreneurship, agriculture, small business management and strategic planning.

This case is most relevant to undergraduates.

This case is about Azad Ahmed who will soon graduate from his business school. He has the option of either landing in a high-paying job or joining his family business. Azad has the task of thinking for his family's future and turning the family business around. The case gives information on the condition of the agriculture sector in Pakistan, issues that the sector is facing, its non-traditional alternatives and the bright future it holds for the farmers who want to enter into agribusiness to capture international markets. The case also talks about how ownership structure of a family farm changes as the family expands further and baton is passed on to the future generations.

The case should get the students to define the term “family business” and weigh the perks and risks of working in a family business; recognize the importance of agriculture and farming in the Pakistani context; evaluate the dynamics of family expectations with respect to collectivistic society; identify the ownership transition stages and transition elements such as trigger points; define the term “agriprenuers”; and set up a business plan for agribusiness.

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‘I LIKE YOUR dress, Miss.’