Developing Deadly Skies

The Canadian War Museum’s exhibition Deadly Skies – Air War, 1914-1918 examines the first air war from the perspective of nine international participants representing Canada, the United States, France, Great Britain, and Germany. Eschewing the romantic mythology of First World War aviation that focuses on the achievements of individual fighter pilots, the exhibition examines four key aspects of the air war: training, observation, bombing, and aerial combat. Adopting an interpretive approach that appeals to intergenerational audiences and that highlights personal experience in the war, the exhibition is presented as a series of life-sized graphic novels, supplemented with key artifacts, photos, audio clips, and videos. The historical and interpretative approaches together present a holistic and modern examination of the world’s first air war

The Essex Scottish Regiment in Operation Atlantic: What Went Wrong?

On 20–21 July 1944 the 6th Canadian Infantry Brigade was engaged in combat operations on Verrières Ridge south of Caen. Enemy resistance was stronger than expected and teh Canadian attack was met by strong German counterattacks supported by armour. During the course of the battle, two units, the Essex Scottish Regiment and the South Saskatchewan Regiment were driven back. In the aftermath of the battle the Essex Scottish Regiment and their commanding officer were criticized for their poor performance. This article examines the battle in an attempt to understand who was to blame. Lieutenant–Colonel B.J.S. MacDonald, the commanding officer of the Essex Scots, was fired for his role in the battle, but this article posits that Brigadier Hugh A. Young bears the greater share of responsibility for the operation’s failure

Strict Liability in Cycling Laws to Ready the Roads for Environmentally Friendly Commuting

Because automobiles cause harmful effects on the environment, the United States should encourage bicycling as an alternative means of transportation to automobiles. Many Americans elect not to cycle as a means of transportation out of fear of a collision with an automobile. Such collisions can be devastating physically and financially, and yet, after a bicycle-automobile collision, cyclists often bear the burden of proving negligence in a suit against the driver, and are often left without a remedy for their injuries. Other countries, such as the Netherlands, use a form of strict liability in lawsuits concerning bicycle-automobile collisions, which shifts the cost of such accidents to automobile drivers. U.S. courts should apply strict liability—as currently used in U.S. tort law—to collisions between cyclists and automobiles. Shifting the cost of bicycle-automobile accidents to automobile drivers will even out the consequences between cyclists and drivers, encouraging drivers to drive more safely, creating safer roads, and encouraging cycling—an environmentally friendly method of transportation—in place of driving a carbon emitting automobile

Liquid-Crystal Blazed-Grating Beam Deflector

A transmission-type nonmechanical multiple-angle beam-steering device that uses liquid-crystal blazed grating has been developed. Sixteen steering angles with a contrast ratio of 18 has been demonstrated. A detailed analysis of the liquid-crystal and poly(methyl methacrylate) blazed-grating deflector was carried out to provide guidance during the deflector’s development. A manufacturing offset compensation technique is proposed to improve the device’s performance greatly. A hybrid approach utilizing electrically generated blazed grating combined with the cascading approach described here yields in excess of 500 deflecting angles

Criminalising a ‘way of life’: The human rights implications of the UK Government’s ban of khat (or miraa) on the farmers of Meru County, Kenya

This paper explores the human rights implications of the categorisation of khat (miraa) as a ClassC Drug under the UK Misuse of Drugs Act 1977 on farmers in the Meru County of Kenya. The paper willargue that the criminalisation of khat is a contravention of the obligations under the International Covenanton Economic, Social and Cultural Rights (ICESCR), and other human rights instruments that provide forthe right of people to enjoy adequate standards of living. As the UK is signatory to the ICESCR and hasratified it into its domestic law, its obligations as a State Party to the Convention extend not only to the UKresidents, but also to the broader international community

Transient coherent Raman scattering in the time and frequency domain

A new type of Raman spectroscopy is presented: After transient excitation of molecular modes coherently scattered Raman spectra are investigated in a depayed probing experiment. The spectral position of the Raman mode is observed after long delay times. The dephasing time is obtained from the time dependence of the scattered amplitudes. Frequency disturbing non-resonant susceptibilities are eliminated. We report on first experimental results of transient coherent Raman spectroscopy of liquid CH3CCl3

Suspended liquid particle disturbance on laser-induced blast wave and low density distribution

The impurity effect of suspended liquid particles on the laser-induced gas breakdown was experimentally investigated in quiescent gas. The focus of this study is the investigation of the influence of the impurities on the shock wave structure as well as the low density distribution. A 532 nm Nd:YAG laser beam with an 188 mJ/pulse was focused on the chamber filled with suspended liquid particles 0.9 ± 0.63 μm in diameter. Several shock waves are generated by multiple gas breakdowns along the beam path in the breakdown with particles. Four types of shock wave structures can be observed: (1) the dual blast waves with a similar shock radius, (2) the dual blast waves with a large shock radius at the lower breakdown, (3) the dual blast waves with a large shock radius at the upper breakdown, and (4) the triple blast waves. The independent blast waves interact with each other and enhance the shock strength behind the shock front in the lateral direction. The triple blast waves lead to the strongest shock wave in all cases. The shock wave front that propagates toward the opposite laser focal spot impinges on one another, and thereafter a transmitted shock wave (TSW) appears. The TSW interacts with the low density core called a kernel; the kernel then longitudinally expands quickly due to a Richtmyer-Meshkov-like instability. The laser-particle interaction causes an increase in the kernel volume which is approximately five times as large as that in the gas breakdown without particles. In addition, the laser-particle interaction can improve the laser energy efficiency

Diffractive optical elements on non-flat substrates using electron beam lithography

The present disclosure describes a technique for creating diffraction gratings on curved surfaces with electron beam lithography. The curved surface can act as an optical element to produce flat and aberration-free images in imaging spectrometers. In addition, the fabrication technique can modify the power structure of the grating orders so that there is more energy in the first order than for a typical grating. The inventors noticed that by using electron-beam lithography techniques, a variety of convex gratings that are well-suited to the requirements of imaging spectrometers can be manufactured

Time resolved observation of resonant and non-resonant contributions to the nonlinear susceptibility χ(3)

The resonant and nonresonant part of χ(3) are distinguished by their different time behavior. The medium is coherently excited by two picosecond light pulses of defined frequency difference and the state of the system is monitored by a third properly delayed probe pulse. Results are presented on neat liquids of carbontetrachloride and cyclohexane and on the mixture of CCl4: C6H12