Automatic visual inspection system for microelectronics

A system for automatically inspecting an integrated circuit was developed. A device for shining a scanning narrow light beam at an integrated circuit to be inspected and another light beam at an accepted integrated circuit was included. A pair of photodetectors that receive light reflected from these integrated circuits, and a comparing system compares the outputs of the photodetectors

Demonstrating the Value of the Public Library: Economic Valuation and the Advocacy Imperative

Promising developments in the field of library valuation over the last fifteen years are providing new options for demonstrating library value. Metrics-gathering has moved away from counting inputs and outputs toward measuring the value of the public library in monetary terms using increasingly sophisticated quantitative methods formerly reserved for business and industry. While it is premature to draw a firm conclusion as to the impact of economic valuation efforts on the success of library advocacy, the adoption of private sector concepts represents a new window of opportunity for library advocates. This critical review synthesizes the library valuation literature, exploring the various frameworks through which library value is being articulated, and finds that econometrics will be most useful to advocates when: 1) library valuation efforts are united with advocacy plans; 2) library services are linked to the achievement of public policy goals; and 3) public libraries are able to connect to a wider funding base

Cross correlation anomaly detection system

This invention provides a method for automatically inspecting the surface of an object, such as an integrated circuit chip, whereby the data obtained by the light reflected from the surface, caused by a scanning light beam, is automatically compared with data representing acceptable values for each unique surface. A signal output provided indicated of acceptance or rejection of the chip. Acceptance is based on predetermined statistical confidence intervals calculated from known good regions of the object being tested, or their representative values. The method can utilize a known good chip, a photographic mask from which the I.C. was fabricated, or a computer stored replica of each pattern being tested

Improved process for making thin-film sodium niobate capacitors

Sodium niobate, formed by high vacuum, flash, and reactive evaporations, has a high dielectric constant and is used as a thin film dielectric in microelectronic capacitors. High purity films are formed from relatively inexpensive, pure starting materials. Crystalline sodium niobate films can be formed on amorphous or crystalline materials

Strongly Charged, Flexible Polyelectrolytes in Poor Solvents -- Molecular Dynamics Simulations

We present a set of molecular dynamics (MD) simulations of strongly charged, flexible polyelectrolyte chains under poor solvent conditions in a salt free solution. Structural properties of the chains and of the solutions are reported. By varying the polymer density and the electrostatic interaction strength we study the crossover from a dominating electrostatic interaction to the regime of strong screening, where the hydrophobic interactions dominate. During the crossover a multitude of structures is observed. In the limit of low polymer density strongly stretched, necklace like conformations are found. In the opposite limit of high polymer density which is equivalent to strongly screened electrostatic interactions, we find that the chains are extremely collapsed, however we observe no agglomeration or phase separation. The investigations show that the density of free charges is one of the relevant parameters which rules the behavior of the system and hence should be used as a parameter to explain experimental results.Comment: 42 pages, including 22 figures and 2 table

Invariant Measures for Dissipative Dynamical Systems: Abstract Results and Applications

In this work we study certain invariant measures that can be associated to the time averaged observation of a broad class of dissipative semigroups via the notion of a generalized Banach limit. Consider an arbitrary complete separable metric space $X$ which is acted on by any continuous semigroup $\{S(t)\}_{t \geq 0}$. Suppose that $\S(t)\}_{t \geq 0}$ possesses a global attractor $\mathcal{A}$. We show that, for any generalized Banach limit $\underset{T \rightarrow \infty}{\rm{LIM}}$ and any distribution of initial conditions $\mathfrak{m}_0$, that there exists an invariant probability measure $\mathfrak{m}$, whose support is contained in $\mathcal{A}$, such that $$\int_{X} \phi(x) d\mathfrak{m} (x) = \underset{T\to \infty}{\rm{LIM}} \frac{1}{T}\int_0^T \int_X \phi(S(t) x) d \mathfrak{m}_0(x) d t,$$ for all observables $\phi$ living in a suitable function space of continuous mappings on $X$. This work is based on a functional analytic framework simplifying and generalizing previous works in this direction. In particular our results rely on the novel use of a general but elementary topological observation, valid in any metric space, which concerns the growth of continuous functions in the neighborhood of compact sets. In the case when $\{S(t)\}_{t \geq 0}$ does not possess a compact absorbing set, this lemma allows us to sidestep the use of weak compactness arguments which require the imposition of cumbersome weak continuity conditions and limits the phase space $X$ to the case of a reflexive Banach space. Two examples of concrete dynamical systems where the semigroup is known to be non-compact are examined in detail.Comment: To appear in Communications in Mathematical Physic

Vitamin D Status among Bangladeshi Women of Reproductive Age

Vitamin D deficiency is of particular concern among women in many south Asian countries due to low availability of vitamin D-rich foods, dark skin pigmentation, and cultural and religious practices that promote the wearing of concealing clothing. However, information regarding the vitamin D status of many subpopulations in south Asian countries is limited. The current study was conducted to assess the vitamin D status of 147 Bangladeshi women of reproductive age and determine whether vitamin D status influences susceptibility to arsenic-associated skin lesions (75 cases, 72 controls). Serum 25(OH)D3 levels were measured using a radioimmunoassay. The mean serum vitamin D level among the women in the current study was 60.1 nmol/L, which is well below the cut-off value of 75 nmol/L defining optimal vitamin D status. Over 81% of the women were below this cut-off value. Vitamin D status was not influenced by the presence of arsenic-associated skin lesions. Sun exposure and very low egg consumption were factors identified as significant predictors of vitamin D status (p\u3c0.05, p\u3c0.04, respectively). Every additional hour of sun exposure per week during work was associated with a 0.32 nmol/L, on average, increase in serum vitamin D levels. Very low egg consumption corresponded to a 10.85 nmol/L lower serum vitamin D level compared to frequent egg consumption. Public health efforts in Bangladesh should promote increased consumption of food sources rich in vitamin D. Vitamin D fortification or supplementation may also be viable options to improve the vitamin D status of the population

Revisiting capital punishment: Factors that matter when receiving the death penalty (a state by state analysis)

Although the death penalty is popular by most accounts, is it really a good social policy? The purpose of this study is to add to this discussion by examining the factors that directly impact death penalty cases. The data used in this study come from the state level database which contains information on all decisions of initial capital direct, state and federal habeas corpus cases between 1973 and 1995. What are the factors that lead some state compared to others to use the death penalty more often? Some have suggested that this could be the result of a minority-majority conflict. The author discusses her findings in the context of the social policy debate and makes recommendations for change