Investigation of welded interconnection of large area wraparound contacted silicon solar cells

An investigation was conducted to evaluate the welding and temperature cycle testing of large area 5.9 x 5.9 wraparound silicon solar cells utilizing printed circuit substrates with SSC-155 interconnect copper metals and the LMSC Infrared Controlled weld station. An initial group of 5 welded modules containing Phase 2 developmental 5.9 x 5.9 cm cells were subjected to cyclical temperatures of + or 80 C at a rate of 120 cycles per day. Anomalies were noted in the adhesion of the cell contact metallization; therefore, 5 additional modules were fabricated and tested using available Phase I cells with demonstrated contact integrity. Cycling of the later module type through 12,000 cycles indicated the viability of this type of lightweight flexible array concept. This project demonstrated acceptable use of an alternate interconnect copper in combination with large area wraparound cells and emphasized the necessity to implement weld pull as opposed to solder pull procedures at the cell vendors for cells that will be interconnected by welding

Passive solar array orientation system /thermal heliotrope/ Final report, 23 Dec. 1968 - 23 Sep. 1969

Tracking requirement, design, and fabrication of passive solar array orientation system using bimetal element

Safe Storage Gun Laws: Accidental Deaths, Suicides and Crime

It is frequently assumed that safe storage gun laws reduce accidental gun deaths and total suicides, while the possible impact on crime rates are ignored. However, given existing work on the adverse impact of other safety laws, such as safety caps for storing medicine, even the very plausible assumption of reduced accidental gun deaths cannot be taken for granted. Our paper analyzes both state and county data spanning nearly twenty years, and we find no support that safe storage laws reduce either juvenile accidental gun deaths or suicides. Instead, these storage requirements appear to impair people's ability to use guns defensively. Because accidental shooters also tend to be the ones most likely to violate the new law, safe storage laws increase violent and property crimes against low risk citizens with no observable offsetting benefit in terms of reduced accidents or suicides. During the first five full years after the passage of the safe storage laws, the group of fifteen states that adopted these laws faced an annual average increase of over 300 more murders, 3,860 more rapes, 24,650 more robberies, and over 25,000 more aggravated assaults. On average, the annual costs borne by victims averaged over $2.6 billion as a result of lost productivity, out-of-pocket expenses, medical bills, and property losses.gun control, crime, suicide, accidental death

Abortion and Crime: Unwanted Children and Out-of-Wedlock Births

Abortion may prevent the birth of ''unwanted'' children, who would have relatively small investments in human capital and a higher probability of crime. On the other hand, some research suggests that legalizing abortion increases out-of-wedlock births and single parent families, which implies the opposite impact on investments in human capital and thus crime. The question is: what is the net impact? We find evidence that legalizing abortion increased murder rates by around about 0.5 to 7 percent. Previous estimates are shown to suffer from not directly linking the cohorts who are committing crime with whether they had been born before or after abortion was legal.crime, abortion, out-of-wedlock briths, human capital

Method of fabricating a photovoltaic module of a substantially transparent construction

A method characterized by the steps of positioning a plurality of uniformly dimensioned photovoltaic cells in registered relation with a plurality of openings formed in a planar tool is disclosed. The method allows acess to the P contact surface of each of the cells. The steps of the method are: (1) connecting the N contact surface of alternate cells to the P contact surface of the cells interposed therebetween, (2) removing therefrom residue of solder flux, (3) applying to the N contact surfaces of the cells a transparent adhesive, (4) placing a common transparent cover plate in engaged relation with the adhesive, (5) placing a film over the circular openings for hermetically sealing the openings, and (6) establishing a vacuum between the film and the cover plate

Topology Change in (2+1)-Dimensional Gravity

In (2+1)-dimensional general relativity, the path integral for a manifold $M$ can be expressed in terms of a topological invariant, the Ray-Singer torsion of a flat bundle over $M$. For some manifolds, this makes an explicit computation of transition amplitudes possible. In this paper, we evaluate the amplitude for a simple topology-changing process. We show that certain amplitudes for spatial topology change are nonvanishing---in fact, they can be infrared divergent---but that they are infinitely suppressed relative to similar topology-preserving amplitudes.Comment: 19 pages of text plus 4 pages of figures, LaTeX (using epsf), UCD-11-9