29,940 research outputs found

    Asian Roboticism: Connecting Mechanized Labor to the Automation of Work

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    Abstract This article reconsiders the present-day automation of work and its transformation of who we are as humans. What has been missing from this important conversation are the social meanings surrounding Asian roboticism or how Asians have already been rendered as “robotic” subjects and labor. Through this racial gendered trope, I assess whether industrial automation will lessen, complicate, or exacerbate this modern archetype. By looking at corporate organizational practices and public media discourse, I believe that Asian roboticism will not simply vanish, but potentially continue to affect the ways such subjects are rendered as exploitable alienated robots without human rights or status

    Body-Worn Cameras: Reducing Citizen Complaints and Improving Relationships

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    Video recordings of police-citizen interactions, most notably those obtained from the dashboard cameras (dashcams) of police cars, have been successful in objectively capturing police-citizen exchanges. However, since police-civilian interactions do not solely occur in front of police cars, dashcams present significant limitations. Off-camera violent, and sometimes fatal, encounters (such as the notorious Ferguson case) have fueled increased public support for body-worn cameras. This is especially true in cases with conflicting accounts from the officer(s), victim(s), and witness(es). Requiring officers to wear bodycams may reduce incidents of force and citizen complaints, and increase officer accountability. This paper will present peer-reviewed research to help create an understanding of officer perceptions about the device, and will evaluate the effects of bodycams on both police officers and the communities they serve. Although bodycams have the potential to improve behaviors of both officers and civilians, its efficacy is dependent on its implementation (i.e., policies). Additionally, this paper will present suggestions for police agencies adopting the use of bodycams. Since bodycams hold promise for helping to rebuild relations between officers and the community, more research and feedback can help address the growing privacy and retention concerns

    Light-emitting diodes and photodiodes in the deep ultra-violet range for absorption photometry in liquid chromatography, capillary electrophoresis and gas sensing

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    Absorbance measurement in the deep ultra-violet range (below 300 nm) has been one of the most widely used detection methods for analytical techniques as a large number of organic compounds have strong absorption bands in the deep UV region. The use of incandescent or discharge lamps coupled to a monochromator for the wavelength selection in a conventional UV detector makes it complex and costly. Light-emitting diodes (LEDs) for the deep UV range commercially available in recent years have become potential alternatives to thermal light sources. LEDs with their relatively narrow emission bandwidths (typically 20 nm) are well suited for absorption photometry in which a monochromator is not required. This dissertation, therefore, concerns the utilization LEDs and photodiodes (PDs) in the deep UV range as radiation sources and light detectors, respectively for absorption photometry in high-performance liquid chromatography (HPLC), capillary electrophoresis (CE) and gas sensing. LEDs were known to perform as light detectors. In measuring systems based on LEDs as light sources, PDs have been normally employed for detection devices. The practical reasons for the use of LEDs as alternatives to PDs, however, have not been demonstrated. Only an advantage of cost-saving was pointed out. In the first project, the performance of LEDs in the light intensity measurement was investigated and compared to that of standard silicon PDs in three different measuring configurations: current follower mode to measure to photocurrents, photovoltaic mode to determine the voltage developed across the diode on irradiation without load and discharge time mode to measure the rate to discharge the junction capacitance of diodes. LEDs as detectors were generally found to be adequate for the analytical work but PDs offered higher sensitivity and linearity as well as provided stable readings with faster settling times. Absorbance detectors for narrow-column HPLC (250 ÎŒm inner diameter) and CE (50 ÎŒm inner diameter) based on deep UV-LEDs and PDs selective for emission wavelengths were developed and evaluated in the quantification of model compounds at 255 and 280 nm. Absorbance measurements were directly obtained by the use of a beam splitter and PDs for reference signals and a logarithmic ratio amplifier-based circuitry to emulate the Lambert-Beer’s law. Narrow-column HPLC is useful for the applications in which the reduction in eluent consumption is desired or only limited amount of samples is available when utmost sensitivity is not required. In CE, the use of a capillary as the separation channel to minimize the peak broadening downscales the detection window to micrometer range which is even much narrower than that of a narrow-bore HPLC. This makes the design and construction of these LED-based detectors for narrow detection channels more challenging than for a standard HPLC as the higher efficiency for light coupling and stray light avoidance is essentially required. Additionally, high mechanical stability is needed to minimize the noise resulted from mechanical fluctuations. The performance of these optical devices at two measured wavelengths was excellent in terms of the baseline noise (low ÎŒAU range), linearity between absorbance values and concentrations (correlation coefficients > 0.999) and reproducibility of peak areas (about 1%). Not only was the potential of a deep UV-LED as a radiation source for absorption spectroscopy investigated for separation techniques but also for the detection of benzene, toluene, ethylbenzene and the xylenes compounds in the gas phase at 260 nm. In the first part of this work, its performance in the acoustic waves excitation was preliminarily investigated with some different measuring systems for the detection of the toluene vapor. It was found that the intensity of a deep UV-LED was insufficient to produce detectable acoustic signals. This was followed by the construction of an absorbance detector for the determination of these target compounds based on the combination of a deep UV-LED and PDs. This optical device was designed to use optical fibers for the light coupling from the LED to a measuring cell and a reference PD, that allows removing a beam splitter previously required for detectors of a narrow column HPLC and CE. Its performance with regard to linearity and reproducibility was satisfactory. Detection limits of about 1 ppm were determined. It could be concluded that viable absorbance detectors for narrow-column HPLC, CE and gas sensing based on deep UV-LEDs and PDs as light sources and light detectors, respectively can be constructed. The performance of these inexpensive LED-based optical devices with regard to linearity, reproducibility and baseline noise was satisfactory and found to be comparable to that of more complex and expensive commercial detectors. These detectors with features of low power consumption and small size are useful for portable battery-powered devices

    Large gaps between consecutive zeros of the Riemann zeta-function. II

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    Assuming the Riemann Hypothesis we show that there exist infinitely many consecutive zeros of the Riemann zeta-function whose gaps are greater than 2.9 times the average spacing

    Twists of automorphic L-functions at the central point

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    We study the nonvanishing of twists of automorphic L-functions at the centre of the critical strip. Given a primitive character \chi modulo D satisfying some technical conditions, we prove that the twisted L-functions L(f.\chi,s) do not vanish at s=1/2 for a positive proportion of primitive forms of weight 2 and level q, for large prime q. We also investigate the central values of high derivatives of L(f.\chi,s), and from that derive an upper bound for the average analytic rank of the studied L-functions
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