Free-form illumination optics

2016 ◽  
Vol 5 (2) ◽  
Author(s):  
Rubén Mohedano ◽  
Julio Chaves ◽  
Maikel Hernández
Keyword(s):  
Injection Molding ◽  
Low Cost ◽  
Free Form ◽  
Modeling Tools ◽  
Design Problems ◽  
Optical Surfaces ◽  
The Past ◽  
Rotationally Symmetric ◽  
Geometrical Constraints ◽  
New Generation

AbstractIn many illumination problems, the beam pattern needed and/or some geometrical constraints lead to very asymmetric design conditions. These asymmetries have been solved in the past by means of arrangements of rotationally symmetric or linear lamps aimed in different directions whose patterns overlap to provide the asymmetric prescriptions or by splitting one single lamp into several sections, each one providing a part of the pattern. The development of new design methods yielding smooth continuous free-form optical surfaces to solve these challenging design problems, combined with the proper CAD modeling tools plus the development of multiple axes diamond turn machines, give birth to a new generation of optics. These are able to offer the performance and other advanced features, such as efficiency, compactness, or aesthetical advantages, and can be manufactured at low cost by injection molding. This paper presents two examples of devices with free-form optical surfaces, a camera flash, and a car headlamp.

The Contribution of Intermediate-Voltage, High-Resolution Electron Microscopy In Materials Science: An Appraisal

1990 ◽  
Vol 48 (1) ◽  
pp. 478-479
Author(s):  
John L. Hutchison
Keyword(s):  
High Resolution ◽  
Materials Science ◽  
High Resolution Electron Microscopy ◽  
Optical Diffraction ◽  
The Past ◽  
Resolution Electron ◽  
Extreme Sensitivity ◽  
Electron Microscopes ◽  
New Generation ◽  
Small Metal Particles

Over the past five years or so the development of a new generation of high resolution electron microscopes operating routinely in the 300-400 kilovolt range has produced a dramatic increase in resolution, to around 1.6 Å for “structure resolution” and approaching 1.2 Å for information limits. With a large number of such instruments now in operation it is timely to assess their impact in the various areas of materials science where they are now being used. Are they falling short of the early expectations? Generally, the manufacturers’ claims regarding resolution are being met, but one unexpected factor which has emerged is the extreme sensitivity of these instruments to both floor-borne and acoustic vibrations. Successful measures to counteract these disturbances may require the use of special anti-vibration blocks, or even simple oil-filled dampers together with springs, with heavy curtaining around the microscope room to reduce noise levels. In assessing performance levels, optical diffraction analysis is becoming the accepted method, with rotational averaging useful for obtaining a good measure of information limits. It is worth noting here that microscope alignment becomes very critical for the highest resolution.In attempting an appraisal of the contributions of intermediate voltage HREMs to materials science we will outline a few of the areas where they are most widely used. These include semiconductors, oxides, and small metal particles, in addition to metals and minerals.

Cross-culture outcomes of a brazilian professor Fulbright in the USA

2017 ◽  
Vol 26 (50) ◽  
pp. 115
Author(s):  
Marcelo Da Silva Leite ◽  
Celeste Gaia
Keyword(s):  
Higher Education ◽  
Low Cost ◽  
Cross Culture ◽  
College And University ◽  
Governmental Agencies ◽  
The Past ◽  
University Curriculum ◽  
Fulbright Scholar ◽  
The Usa ◽  
Higher Education Costs

Over the past decade due the expansion of globalization there has been an increasing emphasis on internationalization among faculty, administration and accrediting agencies in the Higher Education.  Although to promote internationalization in the Higher Education, costs are a big challenge, one way to have the international actions with low cost, it is seeking for grants from different governmental agencies and foundations.The Fulbright Scholar program provides a long-standing and externally-funded means for internationalizing college and university curriculum. This article is going to share the perspective   of a Brazilian Fulbright Scholar at an American college and the institution perspective of the Fulbright scholar participation at the College.

Molecular Epidemiology and Biomarkers in Etiologic Cancer Research: The New in Light of the Old

2020 ◽  
Author(s):  
Lungwani Muungo
Keyword(s):  
Gene Expression ◽  
Cancer Research ◽  
Molecular Epidemiology ◽  
Exposure Assessment ◽  
Large Scale ◽  
First Generation ◽  
Cancer Epidemiology ◽  
Policy Changes ◽  
The Past ◽  
New Generation

The purpose of this review is to evaluate progress inmolecular epidemiology over the past 24 years in canceretiology and prevention to draw lessons for futureresearch incorporating the new generation of biomarkers.Molecular epidemiology was introduced inthe study of cancer in the early 1980s, with theexpectation that it would help overcome some majorlimitations of epidemiology and facilitate cancerprevention. The expectation was that biomarkerswould improve exposure assessment, document earlychanges preceding disease, and identify subgroupsin the population with greater susceptibility to cancer,thereby increasing the ability of epidemiologic studiesto identify causes and elucidate mechanisms incarcinogenesis. The first generation of biomarkers hasindeed contributed to our understanding of riskandsusceptibility related largely to genotoxic carcinogens.Consequently, interventions and policy changes havebeen mounted to reduce riskfrom several importantenvironmental carcinogens. Several new and promisingbiomarkers are now becoming available for epidemiologicstudies, thanks to the development of highthroughputtechnologies and theoretical advances inbiology. These include toxicogenomics, alterations ingene methylation and gene expression, proteomics, andmetabonomics, which allow large-scale studies, includingdiscovery-oriented as well as hypothesis-testinginvestigations. However, most of these newer biomarkershave not been adequately validated, and theirrole in the causal paradigm is not clear. There is a needfor their systematic validation using principles andcriteria established over the past several decades inmolecular cancer epidemiology.

Vēsturiskā atmiņa Latvijas teātra jaunās paaudzes mākslinieku darbos: izrādes „Dvēseļu utenis” piemērs

2020 ◽  
pp. 269-275
Author(s):  
Ieva Rodiņa
Keyword(s):  
Historical Memory ◽  
Intergenerational Relationships ◽  
Phenomenological Approach ◽  
Political Theater ◽  
Hermeneutic Phenomenological ◽  
The Past ◽  
The Social ◽  
Humanistic Study ◽  
New Generation ◽  
Flea Market

The aim of the research “Historical Memory in the Works of the New Generation of Latvian Theater Artists: The Example of “The Flea Market of the Souls” is to focus on the current but at the same time little discussed topic in Latvian theater – the change of generations and the social processes connected to it, that are expressed on the level of world views, experiences, intergenerational relationships. Most directly, these changes are reflected in the phenomenon of historical memory. The concept of “postmemory” was defined by German professor Marianne Hirsch in 1992, suggesting that future generations are closely related to the personal and collective cultural traumas of previous generations, which are passing on the past experience through historical memory, thus affecting the present. Grotesque, self-irony, and focusing on socio-political, provocative questions and themes are the connecting point of the generation of young Latvian playwrights born in the late 1980s and early 1990s, including such personalities as Jānis Balodis, Rasa Bugavičute-Pēce, Matīss Gricmanis, Justīne Kļava, etc. However, unlike Matīss Gricmanis or Janis Balodis who represent the aesthetics of political theater, in Justīne Kļava’s works, sociopolitical processes become the background of a generally humanistic study of the relationships between generations. This theme is represented not only in “The Flea Market of the Souls”, but also in other plays, like “Jubilee ‘98” and “Club “Paradise””. The tendency to investigate the traces left by the Soviet heritage allows to define these works as autobiographical researches of the identity of the post-Soviet generation, analyzing life in today's Latvia in terms of historical memory. Using the semiotic, hermeneutic, phenomenological approach, the play “The Flea Market of the Souls” and its production in Dirty Deal Teatro (2017) are analyzed as one of the most vivid works reflecting the phenomenon of historical memory in recent Latvian original drama.

Free Form Low Cost Fabrication Using Titanium

2007 ◽  
Author(s):  
Corby G. Anderson ◽  
John J. Krstulich
Keyword(s):  
Low Cost ◽  
Free Form

An Assessment of a Low-Cost Wastewater Disposal System after Twenty-Five Years of Operation

1987 ◽  
Vol 19 (5-6) ◽  
pp. 701-710 ◽  
Author(s):  
B. L. Reidy ◽  
G. W. Samson
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Wastewater Disposal ◽  
Industrial Base ◽  
Industrial Wastewaters ◽  
The Past ◽  
Gasification Process ◽  
Appropriate Treatment ◽  
Environmentally Safe ◽  
Coal Resource

A low-cost wastewater disposal system was commissioned in 1959 to treat domestic and industrial wastewaters generated in the Latrobe River valley in the province of Gippsland, within the State of Victoria, Australia (Figure 1). The Latrobe Valley is the centre for large-scale generation of electricity and for the production of pulp and paper. In addition other industries have utilized the brown coal resource of the region e.g. gasification process and char production. Consequently, industrial wastewaters have been dominant in the disposal system for the past twenty-five years. The mixed industrial-domestic wastewaters were to be transported some eighty kilometres to be treated and disposed of by irrigation to land. Several important lessons have been learnt during twenty-five years of operating this system. Firstly the composition of the mixed waste stream has varied significantly with the passage of time and the development of the industrial base in the Valley, so that what was appropriate treatment in 1959 is not necessarily acceptable in 1985. Secondly the magnitude of adverse environmental impacts engendered by this low-cost disposal procedure was not imagined when the proposal was implemented. As a consequence, clean-up procedures which could remedy the adverse effects of twenty-five years of impact are likely to be costly. The question then may be asked - when the total costs including rehabilitation are considered, is there really a low-cost solution for environmentally safe disposal of complex wastewater streams?

The Twenty-first Century

2018 ◽  
Author(s):  
Alexander Gillespie
Keyword(s):  
Environmental Sustainability ◽  
First Century ◽  
Bad News ◽  
Good News ◽  
Species Loss ◽  
The Past ◽  
Scientific Terms ◽  
Twenty First Century ◽  
Open Question ◽  
New Generation

The cumulative environmental challenge of sustainable development in the twenty-first century is larger than anything humanity has ever had to deal with in the past. The good news is that solid progress is being reached in the understanding of issues in scientific terms and understanding what needs to be done. The bad news is twofold. First, although many of the environmental problems of earlier centuries are now being confronted, a new generation of difficulties is eclipsing what were the older difficulties. Secondly, much of the progress is being achieved by the wealthier parts of the planet, rather than the developing world. From population growth to climate change to unprecedented habitat and species loss, whether environmental sustainability can be achieved in the twenty-first century is an open question.

Economic Consequences of War

1943 ◽  
Vol 3 (S1) ◽  
pp. 1-8
Author(s):  
Curtis P. Nettels
Keyword(s):  
Low Cost ◽  
Economic Consequences ◽  
Competitive Advantages ◽  
Competitive Position ◽  
The Past ◽  
History Of ◽  
Costs Of Production ◽  
Foreign Competitors

One influence of war has repeatedly asserted itself in the past—an effect on the costs of production and on the competitive position of the industries and firms of victorious or neutral nations. This subject needs more study, but certain facts suggest a hypothesis, of three parts. First: war expands some industries or concerns, increases their efficiency, enables them to operate, at the end of the struggle, on a comparatively low-cost basis, intensifies their competitive advantages, and improves their position in relation to foreign competitors. Second: war—for the duration—bolsters up some high-cost units by enabling them to sell at a profit all they can produce. The end of the war places such high-cost units at a disadvantage in the process of absorbing the shocks of the transition to a peacetime economy. Third: the history of postwar periods usually exhibits a sharp contest between such low-cost and high-cost enterprises. While “low cost” and “high cost” may refer to the relative positions of units within the same country, in most of this discussion, the terms will be applied to the producers of one country (either victor or neutral) to mean that their costs are low or high in comparison with those of their foreign competitors.

scholarly journals Normative Aspects of Nudging in the International Sphere

AJIL Unbound ◽  
2021 ◽  
Vol 115 ◽  
pp. 263-267
Author(s):  
Doron Teichman ◽  
Eyal Zamir
Keyword(s):  
Energy Consumption ◽  
Organ Donation ◽  
Low Cost ◽  
National Level ◽  
The Past ◽  
The People ◽  
Posthumous Organ Donation ◽  
Regulatory Problems

The use of nudges—“low-cost, choice-preserving, behaviorally informed approaches to regulatory problems”—has become quite popular at the national level in the past decade or so. Examples include changing the default concerning employees’ saving for retirement in a bid to encourage such saving; altering the default about consent to posthumous organ donation to increase the supply of organs for transplantation; and informing people about other people's energy consumption to spur them to reduce theirs. Nudges are therefore used to promote the welfare of the people being nudged, and of society at large. However, the use of nudges has sparked a lively normative debate. When turning to the international arena, new arguments for and against nudges can be raised. This essay focuses on the normative aspects of using nudges in the international arena.

Fused Ambipolar Aza-isoindigos with NIR absorption

2021 ◽  
Author(s):  
Liping Yao ◽  
Danlei Zhu ◽  
Hailiang Liao ◽  
Sheik Haseena ◽  
Mahesh kumar Ravva ◽  
...  
Keyword(s):  
Organic Semiconductors ◽  
High Performance ◽  
Low Cost ◽  
Light Weight ◽  
The Past ◽  
Pi Conjugated ◽  
Nir Absorption ◽  
Conjugated Organic Semiconductors

Due to their advantages of low-cost, light-weight, and mechanical flexibility, much attention has been focused on pi-conjugated organic semiconductors. In the past decade, although many materials with high performance has...

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