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We present an ultra-high frequency radio frequency identification based wireless communication set-up for paper-based point-of-care diagnostic applications, based on a sensing radio frequency identification chip. Paper provides a low-cost, disposable platform for ease of fluidic handling without bulky instrumentation, and is thus ideally suited for point-ofcare applications; however, result communication – a crucial aspect for healthcare to be implemented effectively – is still lacking. Printing of radio frequency identification antennas and electronic circuitry for sensing on paper are presented, with read out of the results using a radio frequency identification reader illustrated, demonstrating the feasibility of developing integrated, all-printed solutions for point-of-care diagnosis in resource-limited settings.

Research on affordable point-of-care health diagnostics is rapidly advancing1. Colorimetric biosensor applications are typically qualitative, but recently the focus has been shifted to quantitative measurements2,3. Although numerous qualitative point-of-care (POC) health diagnostic devices are available, the challenge exists of developing a quantitative colorimetric array reader system that complies with the ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, Deliverable to end-users) principles of the World Health Organization4. This paper presents a battery powered 8-bit tonal resolution colorimetric sensor circuit for paper microfluidic assays using low cost photo-detection circuitry and a low-power LED light source. A colorimetric 3×3-pixel array reader was developed for rural environments where resources and personnel are limited. The device sports an ultralow-power E-ink paper display. The colorimetric device includes integrated GPS functionality and EEPROM memory to log measurements with geo-tags for possible analysis of regional trends. The device competes with colour intensity measurement techniques using smartphone cameras, but proves to be a cheaper solution, compensating for the typical performance variations between cameras of different brands of smartphones. Inexpensive methods for quantifying bacterial assays have been shown using desktop scanners, which are not portable, and cameras, which suffer severely from changes in ambient light in different environments. Promising colorimetric detection results have been demonstrated using devices such as video cameras5, digital colour analysers6, flatbed scanners7 or custom portable readers8. The major drawback of most of these methods is the need for specialized instrumentation and for image analysis on a computer.

A fiber optic Bragg grating (FBG) sensor and interrogation scheme has been designed to capture the momentary peak pressure forces in the nip of two adjacent paper machine rolls. The spatial distribution of these nip forces along circumference and length of the roll, for production speeds of up to 2000 m/min are investigated. Additionally, this FBG sensor system measures the temperature distribution in the roll cover. FBG sensor embedding has been optimized for the implementation of pressure force measurements in various roll cover materials. High strength draw tower grating (DTG) sensor arrays were used for the embedding process combined with spectrometric interrogation and autonomous power supply technologies. This results in an extremely robust fiber optic sensor system for operation at rotation speeds of 700 rpm, equivalent to centrifugal accelerations of 300 G. These measurements enable immediate quality control during various stages of the high-speed paper production process. © (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Roughness of a paper surface is particularly important in paper and board destined to be printed. Surfaces are often coated and the amount of coating and method of application used depends on the roughness of the base paper. We present a method of measure of the roughness of the paper based in the analysis of speckle pattern on the surface. Images are captured by means of a simple configuration using a laser and a camera CCD. Then, we apply digital image processing using the co-occurrence matrix, so this method can be considered as a non-contact surface profiling method, that can be used online.

For the last eight years, the solar industry has experienced annual growth of over 40%. Concerns over the rising costs of conventional energy, as well as its environmentally damaging effects, have been driving this vigorous investment in solar energy. Now, with grid parity almost upon us, the solar industry is reassessing what it will look like as a commoditized, mainstream power source. Do the best opportunities for solar lie with a centralized or decentralized model of production? What are the most bankable PV technologies? How can costs be cut and efficiencies improved to take things to the next level and make that last push to reach grid parity? In this paper, we will examine Solaria's LCPV technology and approach to the future of solar power.

In present work the capabilities of an optical coherence tomography (OCT) setup to visualize paper structure are analyzed by means of Monte Carlo-simulation of the OCT images. The OCT setup at 910 nm was considered. Efficiency of several different optical clearing agents (OCA) for increasing the quality of the obtained images was studied. A multilayer non-planar edged paper model was developed for the characterization of a paper sample and simple recovery of its parameters. The effect of the setup parameters on the obtained OCT-images was studied. It was shown by comparison with the experimental data that the developed model provides satisfactory resemblance of simulated and experimental images of papers sample structure.

The proliferation of digital information is leading to a wide range of applications which make it desirable to display data easily in many locations, all changeable and updateable. The difficulty in achieving such ubiquitous displays is the cost of signage, the cost of installation, and the software and systems to control the information being sent to each of these signs. In this paper we will talk about a networked system of such signs which are made from gyricon electronic paper. Gyricon electronic paper is a reflective, bistable display which can be made in large web sheets at a reasonable price. Since it does not require a backlight nor does it require power to refresh the display image, such technology is ideal for making signs which can be run on batteries with extremely long battery life, often not needing replacement for years. The display also has a very broad illumination scattering profile which makes it readily viewable from any angle. The basic operating mechanism of the display, its manufacturing technique, and achieved performance will be described, along with the description of a networked solution using many such signs controlled with system software to identify speakers and meetings in conference rooms, hospitality suites, or classrooms in universities. Systems will also be shown which are adapted to retail pricing signage and others which can be used for large format outdoor billboards.

The paper presents benefits of optical time-of-flight spectroscopy for the pulp and paper characterization. A semiconductor pulse laser and a streak camera as the photodetector were utilized in experimental part of research described in this paper. Distribution of the time of flight of photons through various kinds of wood pulp (e.g. pulp after mechanical treatment coming both fi-om tree species giving hard and soft wood and pulp after thermo-mechanical treatment) was measured. The pulp samples used in the measurements had consistency ranging from 0 to 5% of dry mass in the suspension. The influence of additives (kaolin, talc and calcium carbonate) present in the suspension on the time of flight distribution of photons was studied as well. Finally, dependence of the time of flight of photons through various kinds of the paper (i.e. newspaper, copy paper, and tissue) on the thickness of the sample was investigated.

The refractive index of paper was determined by measuring the propagation delay of photons in optically cleared paper boards. The determination was based on the assumption that photon propagation delay achieves minimum value as the paper is optimally cleared. The measured paper sheets was made from elemental chlorine-free market pulp, i.e. fully bleached, unbeaten, softwood kraft pulp. Nine different clearing agents with a refraction index between 1.329 and 1.741 were eLuperimented with. According to the streakmem measurements, the refractive index of the test paper was 1.557.

Technological development is seen as one of the fundamental forces in shaping the modern economies. The effects and the role of technological development are also central questions in many issues of environmental protection. This paper presents the results of a life cycle assessment study of the Finnish pulp an paper industry. Three comparative scenarios are drawn. Two scenarios describe the technological levels and production volumes of 1993 and 1997. A comparison scenario with the production volumes of 1997 and the technological level of 1997 describes the effects avoided by improvements. The results demonstrate that technological development has had considerable effects on the material flows of the industry within a relatively short period of time. Changes in most material flows result from various improvements. The environmental performance of the industry has been improved by both changes in operative practices as well as capital investments. The study fails to describe some aspects of realized developments and thus indicates that factors connected to technological change are highly problematic for LCA modelling.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.