VoIP Goes the Bad Guy: Understanding the Legal Impact of the Use of Voice Over IP Communications in Cases of NSA Warrantless Eavesdropping, 24 J. Marshall J. Computer & Info. L. 227 (2006)

For purposes of national security, the Bush administration delegated authority to the National Security Administration (“NSA”) to conduct warrantless surveillance of Americans; and such surveillance defies tradition. At the same time, emerging communications technology, like Voice over Internet Protocol (“VoIP”), complicates the already controversial issue by generating uncertainty about how courts will analyze warrantless surveillance of such forums. The problem lies in outdated communications and surveillance regulations, which effectively address older communications forums, like the telephone, but encounter stifling ambiguity vis-à-vis VoIP and other new forums. VoIP is a relatively new technology, but it encompasses the large and ever-growing use of voice conversations over the Internet. The U.S. must govern this area with regulations that accommodate the rapid development of this and other new communications technologies. In the hands of wrongdoers, VoIP has the power to wield extraordinary harm, which supports warrantless surveillance in this domain. Notwithstanding the obvious national security concern, however, such intrusive governmental action jeopardizes the privacy of American citizens. Therefore, in modifying its policies, the Legislature must balance national security interests and citizens’ privacy interests, while ensuring conformity to acceptable legal standards. A failure to modify existing regulations to adapt and grow with new technologies places the interests of both this nation and its people at stake

Acoustic monitoring of additive manufacturing for damage and process condition determination

Additive manufacturing (AM) is the process of forming materials in a layer-by-layer fashion, as opposed to more traditional, subtractive manufacturing methods. The method enables the inclusion of features not possible with classical methods such as complex internal and external geometry, and gradations of material composition for some processes. While these geometry and composition variations are an enabling capability for design freedom and customization, uncertainty remains regarding the quality and in the resulting material properties and defect distributions for AM parts. There remains a need to identify appropriate means and methodologies to inspect them. AM is well suited for low production volume, complex, high value components and thus, real-time, in-situ characterization on a part-by-part basis of these materials has become of interest to academia and industry. Acoustic methods have been utilized for monitoring cutting, milling, welding, and laser processing of metals and polymers in the past. In this work, an acoustic monitoring array was utilized to monitor directed energy deposition of Ti-6AL-4V onto a steel substrate. Temporal waveforms were recorded intermittently and passively, and later analyzed using temporal and spectral methods. Metallographic analysis and comparison of crack densities with acoustic metrics are shown to correlate well as a material damage indicator. Low amplitude process noise is also shown to correlate with the process state, for which 3 variations around nominal deposition parameters were tested

Capacitive Sensing of Intercalated H2O Molecules Using Graphene

Understanding the interactions of ambient molecules with graphene and adjacent dielectrics is of fundamental importance for a range of graphene-based devices, particularly sensors, where such interactions could influence the operation of the device. It is well-known that water can be trapped underneath graphene and its host substrate, however, the electrical effect of water beneath graphene and the dynamics of how it changes with different ambient conditions has not been quantified. Here, using a metal-oxide-graphene variable-capacitor (varactor) structure, we show that graphene can be used to capacitively sense the intercalation of water between graphene and HfO2 and that this process is reversible on a fast time scale. Atomic force microscopy is used to confirm the intercalation and quantify the displacement of graphene as a function of humidity. Density functional theory simulations are used to quantify the displacement of graphene induced by intercalated water and also explain the observed Dirac point shifts as being due to the combined effect of water and oxygen on the carrier concentration in the graphene. Finally, molecular dynamics simulations indicate that a likely mechanism for the intercalation involves adsorption and lateral diffusion of water molecules beneath the graphene.Comment: E.J.O. and R.M. made an equal contribution to this wor