Different geometries for special relativity

This paper introduces a different time-measuring convention for special relativity (SR), where a time interval t can be measured by dc, the distance traveled from an origin by the spherical wave-front of a light pulse c. Adoption of this convention leads to a Euclidean geometry for SR, different from the Euclidean geometry already proposed by Montanus. The present geometry is governed by the functions of the circle, rather than the hyperbola, and the spherical wave-front of a light pulse provides both a fourth set t of frame-dependent coordinate points and a parameter w for measuring intervals that are invariant between reference frames. Since sine values under the circle range from 1 to 0, rather than 1 to ¥, the new model does not allow, for a reference frame velocity » c, any interval to have length » ¥. Furthermore, the form of the new model excludes any notion of “travel” with respect to time

Design against nature

The process of disinfecting pits technology against nature. This issue is considered through examination of the design and development of a microwave disinfecting system for contact lenses. Here, technology intervenes to remedy a naturally occurring deficiency in human sight and the design solution requires indiscriminate annihilation of ‘lesser’ forms of life. With the march of science transforming our ethical and theological visions, questions are raised about the justifications for this strategy and the senses in which it may be seen to be responsible. The competing discourses of responsibility reveal the attraction of seeking to develop such technologies through multidisciplinary teams

Alternative conventions and geometry for special relativity

This paper argues that Einstein’s conventionalist definition of time is sufficient for, but not necessary to the geometric modelling of Special Relativity. A different convention allows that any time interval t, can be measured by dc, the distance travelled from an origin by the spherical wave-front of a light pulse, c. This means that the relationships represented by the hyperbolic geometry of Minkowski can also be represented by circular function geometry (CFG), where the spherical surface of c provides both a fourth set t, of frame-dependent co-ordinate points and a parameter s, for measuring intervals that are invariant between reference frames. However, sine values under the circle range from 1-0, rather than 1-∞. This does not allow that for a reference frame velocity ≈ c, any interval length ≈ ∞. Furthermore, since CFG does not subdivide space-time into past and future zones, it excludes the possibility of backwards time travel for signal velocities > c

Expert systems and the emergence of teledesign

This paper considers the extent to which the amateur use of expert systems for home design challenges traditional views of the design process. The issues are examined in the context of competing definitions of design. The emergence of a design process characterised as ‘teledesign’ is then considered, wherein retailers provide a CAD/CAM service to consumers, allowing the latter to use expert systems to modify template designs and get products fabricated to their own specifications. Such a system may be seen to empower consumers as designers, rather than just selectors of products, and would differ considerably from established paradigms of design, manufacture and consumption, such as that given by Baudrillard

Effects of microwave irradiation on the parameters of hydrogel contact lenses

Ten brands of hydrogel contact lenses were selected from five of the six British Approved Name lens classification groups to test in vitro the effects of repeated heat disinfection by means of microwave irradiation. Each lens type was tested over a number of cycles corresponding to its scheduled number of wearing days. The total diameter and back vertex power of all 80 test and 12 control lenses were measured at the end of their relevant cycling period. The back optic zone radius, center thickness, and water content were measured for 40 test and 8 control lenses. No clinically significant change was found in any of the 10 brands tested. Statistically significant changes were found in the back optic zone radius of the Frequency 55 group and water content of the Precision UV group. Some discoloration was noted in Ciba Visitint lenses

Testing of a dual-mode microwave care regimen for hydrogel lenses

Purpose. To test the design of a patient care regimen for soft lenses that aims to provide the highest standards of disinfecting through use of domestic microwave cookers, while also providing storage equipment and solution that enable patients to follow a conventional cold disinfecting regimen when traveling. The cleaning efficacy of surfactant agents during microwave treatment was also considered. Methods. The microbiologic performance of the regimen and its disinfecting apparatus was tested according to the Food and Drug Administration (FDA) protocols for contact lens heat disinfectors. Subsequently, a prospective pilot clinical trial of the regimen involving 15 subjects was carried out to the protocols of the FDA and International Standards Organization 11,980:1997. Results. Lenses inoculated with 107 colony-forming units (cfu) of Enterococcus faecalis were disinfected to 0 cfu by a 12-s irradiation of a compact disinfecting case that held the lenses suspended in 12 ml saline. A proof of operation indicator performed correctly for all 10 cases tested. No adverse reactions were found in the pilot patient trial, using Renu multipurpose (Bausch & Lomb, Rochester, NY) as the test solution, and no statistically significant difference was found between test and control groups in respect of any sign. However, the greater incidence of edema, palpebral hyperemia, and lens front-surface deposition in the microwave test group may be clinically significant

Clinical trial of a patient-operated microwave care system for hydrogel contact lenses

The clinical effects of a patient-operated system of microwave disinfection for soft contact lenses were assessed in a prospective pilot trial involving 103 patients who were drawn from five optometric practices. Fifty-six subjects used the test system for 1 month, and 13 subjects continued use for a total of 3 months. Both test and control subjects were examined for clinical signs using slitlamp tests. After 1 month, the incidence of all signs reported in the microwave group was not significantly greater than in the control group (p = 0.267), and the same was true after 3 months (p = 0.214). There was a significantly greater incidence of edema in the 1-month test group and of staining in the control group. UV spectroscopic examination of worn lenses from test subjects exhibiting significant signs did not show a higher level of deposition than on lenses worn by control subjects (p = 0.397)

Impacts of stratospheric aerosol geoengineering strategy on Caribbean coral reefs

Purpose: Currently, negotiation on global carbon emissions reduction is very difficult due to lack of international willingness. In response, geoengineering (climate engineering) strategy is proposed to artificially cool the planet. Meanwhile, as the harbor around one-third of all described marine species, coral reefs are the most sensitive ecosystem on the planet to climate change. However, until now, there is no any quantitative assessment on impacts of geoengineering on coral reefs. In this study, we model impacts of stratospheric aerosol geoengineering on coral reefs. Design/methodology/approach: We will use the HadGEM2-ES climate model to model and evaluate impacts of stratospheric aerosol geoengineering on coral reefs. Findings: This study shows that a) stratospheric aerosol geoengineering could significantly mitigate future coral bleaching throughout the Caribbean Sea; b) Changes in downward solar irradiation, sea level rise and sea surface temperature caused by geoengineering implementation should have very little impacts on coral reefs; c) although geoengineering would prolong the return period of future hurricanes, this may still be too short to ensure coral recruitment and survival after hurricane damage