Africans in Colonial America (1619-1763) Essays - Economy

Africans in Colonial America (1619-1763) Essays - Economy Africans in Colonial America (1619-1763) Directions Please save this document before you begin working on the assignment. Type your answers directly in the document. _________________________________________________________________________ Part 1 Answer the following questions in two to three complete sentences. (Each question is worth three points) 1. Describe how African Americans resisted enslavement during colonial times. What were the results of these efforts? Type your response here: 2. How did an indentured servant differ from an enslaved person? Type your response here: 3. Describe an enslaved African's working conditions and living arrangements on a plantation. Type your response here: 4. How did racial prejudices and racist laws affect romantic unions between Africans and Europeans in the colonial period? Type your response here: 5. Describe two reasons why slavery did not develop in the northern colonies. Type your response here: 6. How does the story of Anthony Johnson and his family reflect the change of legal status of African Americans in Virginia in the 1600s? Type your response here: Part 2 Answer the following questions by writing at least a paragraph (five sentences). (Each question is worth ten points) 1. Why did the system of indentured service give way to slavery in North America? Give at least two reasons. Type your response here: 2. Agree or disagree with the following statement. The lives of European indentured servants in American colonies were generally good and always better than the lives of Africans there. Be sure to offer evidence for your views. Type your response here: - Submission - 2013 EDMENTUM, INC.

Health And Safety Issues Of Immersive Virtual Reality Technologies Essays

Health And Safety Issues Of Immersive Virtual Reality Technologies Essays Health And Safety Issues Of Immersive Virtual Reality Technologies Paper Health And Safety Issues Of Immersive Virtual Reality Technologies Paper Gupta, Wantland and Klien (1996) propose that many of the peripheral equipments used in VR are possible fomites. A fomite is a safe object that is capable to harbour pathogenic organisms and as such, may work as an agent for the transmission of infectivity. They then propose that airborne pathogens and skin flora flourish in atmospheres as similar to those of HMDs and hand controller devices. An added thought at this point is that HMDs are frequently of enclosed design and produce a substantial heat in powering the displays. This can regularly lead to some sweating for the user particularly if the immersive task needs a definite amount of physical activity. Immersion Injuries Both Gupta et al. (1996) and Viirre (1993) propose that there may also be a chance of injury while the user is using a fully immersive HMD. As Viirre proposes, when a user is using an HMD, they are operationally blind in actual terms. This can cause problems due to conflict with real world objects or probably the VR system cabling and even if the user has some external vision, the forceful immersive scene may divert attention from the real world. Additional, many HMDs also offer sound cues for the user that effectively reduce aural stimulation from the real world. Physiological Physiological problems are probably the most well documented and at present, well researched sickness problem recently credited to VR systems. In fact some accounted physiological side-effects such as simulator sickness have been studied for some time. Of the probable physiological side-effects, visual symptoms and motion sickness type symptoms emerge to cause the most concern. As a result, majority of the studies into physiological results has been focussed in these areas. Visual Issues The visual presentation of the virtual atmosphere is very significant. The processing and organisation of visual input engages the use of a larger portion of the brain than for any other sense. North (1993) approximated that for a complicated task such as driving, 90 per cent of the received information is visual. It is therefore not astonishing that producers go to great lengths to offer a compelling visual atmosphere. As proposed however, stereoscopic semi-immersive systems may have added side-effects. One of the prime causes for the origin of side-effects is proposed to be the dissociation of accommodation and union in the visual system. Indication of Near Market Development In 1993, Mon-Williams, Wann and Rushton accounted physiological symptoms in many subjects pursued by immersion in an HMD. Of the 20 subjects who contributed in their experiment, 12 complained of symptoms such as headache, eyestrain and nausea and 4 displayed a transient decrease in binocular visual acuity. The subjects also displayed symptoms of binocular stress that included modifications in heterophoria and an increment in near point of junction. Mon-Williams and Pascal (1995) proposed that these symptoms of visual/binocular stress were connected, not only to poor image quality and close working distance of the screens, but more primarily with the inconsistency between space and convergence requirement when using a stereoscopic HMD. This problem will take place in any stereoscopic system where the main image is shaped on a flat screen and stereo images are presented by demonstrating slightly dissimilar images to each eye. In the natural atmosphere, focus and union are essentially connected. If one accommodates (focuses) on a near object, the eyes will automatically unite. Likewise, if focus is transformed to a distant object, the eyes will mechanically deviate slightly (see Figure 1). Using stereoscopic display devices such as shutter glasses or HMDs, this will not happen. In this situation, the focal demand is always invariable but the convergence demand modifies as the user regards objects at different geometric depths in the virtual world. This accommodation/ convergence is not a natural occurrence and has been said to result in visual stress. Probable Health Benefits Mutually Howarth (1994) and Wilson (1996) point out that in addition to looking for problems; it is significant to make out that VR methods may also attest helpful in various applications. Recently there is much investigation work being carried out in the VR field that will be of benefit to users. In terms of physical issues, more usual interface methods may reduce static posture problems, the use of LCD displays may minimise vision problems associated with CRT displays and physical loads associated with keying (Wilson, 1996). VR also presents a much improved method for health and safety training, even though as Howarth (1994) proposes, this function is largely concealed. VR methods can be used in ergonomic assessment of workspace plan, for fast prototyping of control interfaces, for the simulation of probably dangerous surroundings such as nuclear plant maintenance and in education and training of users in parts such as the maintenance of complicated machinery. As Howarth says, the fact that the use of VR has helped an operator avoid an accident or react correctly in the event of a crisis is largely unseen. VR also has numerous applications that can be directly linked to healthcare. In a white paper on the usage of Virtual Surroundings for Health Care, Moline (1995) shows numerous parts where patient care can be assisted by VR methods. These include:  ·Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The use of VR for remote telesurgery.  ·Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   VR methods used in local surgery such as endoscopy, where the surgeon manipulates instruments by viewing a TV monitor.  ·Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   VEs used as surgical simulators or trainers.  ·Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   VEs used as therapy devices to reduce anxiety or fear. One example is dentists using 3D eyeglasses to divert a patients attentiveness during dental operations  ·Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   VEs are also being used to reduce phobias such as agoraphobia and vertigo. North, North and Coble (1996) present an indication of existing work in the use of VR methods to decrease phobias in their book VR Therapy. 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