Blind spot detection

There has been little advancement of intelligent transportation systems research dedicated to motorcycle safety. Motorcycle ADAS (Advanced Driver Assistance Systems) could improve the safety of the rider as well. There is however a nrrmber of obstacles that will likely lead to a slower uptake compared to passenger cars, including the challenges posed by the Human Machine Interface rcqrrircments, costs and the required support from the motorcyclists community. In spite of these obstacles, ITS has a role to play to increase motorcycle safety in the future. e-Call, blind spot detection, curve and collision warning systems are suitable applications for the motorcycle - once sufficiently developed for them. 

Blind spot detection Round view systems - Hoao-updisplay ... 

In addition to the practical advantages of replacing side-view mirrors with camera monitor systems, such systems also have strategic importance for the fumre. Sensors on the side of the vehicle will convey essential information for autonomous driving in the fumre. Functions such as blind spot detection, trailer support, lane detection, lane change assist and turn assist are steps on the path to autonomous driving. 

Muns ENDOR mvolves observation of the stimulated echo intensity as a fimction of the frequency of an RE Ti-pulse applied between tlie second and third MW pulse. In contrast to the Davies ENDOR experiment, the Mims-ENDOR sequence does not require selective MW pulses. For a detailed description of the polarization transfer in a Mims-type experiment the reader is referred to the literature [43]. Just as with three-pulse ESEEM, blind spots can occur in ENDOR spectra measured using Muns method. To avoid the possibility of missing lines it is therefore essential to repeat the experiment with different values of the pulse spacing Detection of the echo intensity as a fimction of the RE frequency and x yields a real two-dimensional experiment. An FT of the x-domain will yield cross-peaks in the 2D-FT-ENDOR spectrum which correlate different ENDOR transitions belonging to the same nucleus. One advantage of Mims ENDOR over Davies ENDOR is its larger echo intensity because more spins due to the nonselective excitation are involved in the fomiation of the echo. 

Fig. 3.1 Detection of light in the eye (a) structure of the human eye (b) distribution of cones and rods in the temporal side of the retina (nasal side is similar except for the blind spot between 12" and IS"" from the fovea).

Although it has the ability for hyperfine selection, the Davies ENDOR sequence is not so sensitive to blind spots as in a Mims ENDOR, and thus it is more useful for detecting powder-pattern ENDOR line shapes. The Davies sequence, however, generally does not give so large a percent ENDOR effect typical Davies ENDOR effects in proteins are approximately 1-15% of the spin echo amplitude. 

In a three-pulse ESEEM experiment the time T between the second and the third pulse is increased while the time x between the first and second pulse is kept constant. In contrast to the two-pulse ESEEM experiment, the three-pulse ESEEM spectra do not contain sum and difference frequencies as illustrated schematically in Fig. 2.21 for an S = Vi species with anisotropic hyperfine coupling due to a proton. Both spectra contain lines with nuclear frequencies and v expected for = /2. The combination lines at v v seen as satellites in the two-pulse spectrum do not appear in the corresponding 3-pulse spectrum. On the other hand lines can escape detection in the 3-pulse spectrum for certain values of the time x between the first and second pulse at so called blind spots. It is therefore customary to record several 3-pulse specfra with different values of x. 

In the solid state, relaxation measurements from the ns—fis blind spot is possible, although the detection of such motions in solution NMR is difficult due to overlapping of the range to overall tumbling motion [138]. In fact. 

Considering the resolution of the nuclear frequency spectrum, this two-pulse echo experiment is not optimal. The nuclear frequencies are here measured as differences of frequencies of the ESR transitions, so that the line widths correspond to those of ESR transitions. The nuclear transitions have longer transverse relaxation times Tin and thus smaller line widths. In fact, if the second mw pulse is changed from a n pulse to a Ji/2 pulse, coherence is transferred to nuclear transitions instead of forbidden electron transitions. This coherence then evolves for a variable time T and thus acquires phase v r or vpT. Nuclear coherence cannot be detected directly, but can be transferred back to allowed and forbidden electron coherence by another nil pulse. The sequence (jt/2)-x-(Jt/2)-r-(jt/2)-x generates a stimulated echo, whose envelope as a function of T is modulated with the two nuclear frequencies v and vp. The combination frequencies v+ and v are not observed. The modulation depth is also 8 211. The lack of combination lines simplifies the spectrum and the narrower lines lead to better resolution. There is also, however, a disadvantage of this three-pnlse ESEEM experiment. Depending on interpulse delay x the experiment features blind spots. Thus it needs to be repeated at several x values. 

The remote-echo detector is shown in Figure 11. In this method the electron spin echo at the end of the pulse sequence, which uses Vi < rnuclear coherence generator, is not recorded. Instead, at the time of echo formation an additional nil pulse transfers the electron coherence to longitudinal magnetization. The echo amplitude information can thus be stored for a time interval up to the order of T. After a fixed time delay h < T l, the z-magnetization is read out using a two-pulse echo sequence with a fixed time interval X2 > r. Remote echo detection can be applied to many experiments, including three-pulse ESEEM and HYSCORE, and thus can eliminate blind spots with an appropriate choice of small ri. Note, however, that it may suffer from reduced sensitivity due to the increased sequence time. 

Systems Obstacle Detection A transport company in Canada reduced at-frult accidents by 34% in 1st year after installation of a radar-based collision warning system with forward-looking and side sensors to warn drivers of obstacles in blind spots. 1 study (Srour et al. 2003). 

You may believe that the accidents could not happen at your plant because you have systems to prevent them. Many of the accidents I describe occurred on plants that had such systems, but the systems were not always followed. The accidents happened because of various management failures failure to convince people that they should follow the systems, failure to detect previous violations (by audits, spot checks, or just keeping an open eye), or deliberately turning a blind eye to avoid conflict or to get a job done quickly. The first step down the road to many a serious accident occurred when someone turned a blind eye to a missing blind (see Chapter 1). 

The next step in validation was to test known positive specimens that had been archived. This approach was important in validating a variety of disorders. In today s environment, however, these specimens, critical to method validation, have become increasingly more difficult to obtain due to privacy concerns and regulations. For example, it was important to obtain blood spots analyzed previously by other methods and compare results in a blinded fashion in order to validate the newer methodology. A fundamental paper for demonstrating the improvement of PKU detection was carried out using this approach. 

A commonly-used device for testing colour perception is the Isihara test. This consists of a number of plates composed of numerous spots of different colours and sizes. Incorporated into this random arrangement are a number of dots, tracing out numerals, which are of a colour distinguishable from the remainder. The colour sensitivity of the observer s eye is assessed by his ability to read these numbers. It is also possible to detect different kinds of colour blindness with the plates. Four of them, for example, each contain two numbers one in scarlet and the other in purple. Those who suffer from panatropy cannot see the scarlet spots and only read the purple ones, but the deuteranopes read only the scarlet numerals those with normal vision see both numbers. (For further information see JORDINSON AND MlNSHALL, J. 5.D.C., 1959, 75, 585.)... 

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