Changing ideas of bodily cleanliness

The modern bathroom reflects Western ideas on the handling of bodily wastes, and consequently ideas of cleanliness. Taking a historical study as the point of departure, the purpose of this paper is to understand the extent to which the idea of cleanliness influences the possibility of converting the water closet to a more sustainable technology. An examination of historical changes demonstrates that our present ideas on cleanliness are distinct in their own way. It also demonstrates that our present ideas of cleanliness represent a drawing together of several loose ends, development towards which having been incoherent. Great variation has been apparent in practices surrounding, and the social importance of, cleanliness. People have lived in different ways and have had different ideas about how to behave. The Roman culture thought of bathing and relieving oneself as social duties. In the Middle Ages, uncleanliness ruled the day as people had a very natural and relaxed attitude to bodily waste. Following the urbanisation process, cleanliness was thought of as a step towards progress and a sanitational cure for epidemics in the cities. In more recent times, cleanliness became a project of orderliness and became institutionalised in society. The water closet is inextricably linked with our present ideas of cleanliness. This could impede a future conversion of the water closet, these ideas in several ways conflicting with the more sustainable toilet system. Nevertheless, it is also a point of this paper to illustrate that our present ideas of cleanliness are not self-evident. On the contrary, our ideas are contextually bound and might thus change, for instance, due to a strengthening of e.g. the environmental discourse

Ramification and cleanliness

This article is devoted to studying the ramification of Galois torsors and of $\ell$-adic sheaves in characteristic $p>0$ (with $\ell\not=p$). Let $k$ be a perfect field of characteristic $p>0$, $X$ be a smooth, separated and quasi-compact $k$-scheme, $D$ be a simple normal crossing divisor on $X$, $U=X-D$, $\Lambda$ be a finite local ${\mathbb Z}_\ell$-algebra, $F$ be a locally constant constructible sheaf of $\Lambda$-modules on $U$. We introduce a boundedness condition on the ramification of $F$ along $D$, and study its main properties, in particular, some specialization properties that lead to the fundamental notion of cleanliness and to the definition of the characteristic cycle of $F$. The cleanliness condition extends the one introduced by Kato for rank one sheaves. Roughly speaking, it means that the ramification of $F$ along $D$ is controlled by its ramification at the generic points of $D$. Under this condition, we propose a conjectural Riemann-Roch type formula for $F$. Some cases of this formula have been previously proved by Kato and by the second author (T.S.)

Contamination control program for the Cosmic Background Explorer: An overview

Each of the three state of the art instruments flown aboard NASA's Cosmic Background Explorer (COBE) were designed, fabricated, and integrated using unique contamination control procedures to ensure accurate characterization of the diffuse radiation in the universe. The most stringent surface level cleanliness specifications ever attempted by NASA were required by the Diffuse Infrared Background Experiment (DRIBE) which is located inside a liquid helium cooled dewar along with the Far Infrared Absolute Spectrophotometer (FIRAS). The DRIBE instrument required complex stray radiation suppression that defined a cold primary optical baffle system surface cleanliness level of 100A. The cleanliness levels of the cryogenic FIRAS instrument and the Differential Microwave Radiometer (DMR) which were positioned symmetrically around the dewar were less stringent ranging from 300 to 500A. To achieve these instrument cleanliness levels, the entire flight spacecraft was maintained at level 500A throughout each phase of development. The COBE contamination control program is described along with the difficulties experienced in maintaining the cleanliness quality of personnel and flight hardware throughout instrument assembly

Public Transportation: Perceptions of Filth Contributing to Poor Health

Public transportation vehicles such as trains or buses have a reputation as unsanitary. Many riders of public transit are concerned with the health risks they are facing in regards to contagion. Perceptions of cleanliness derive from public health historically, with class, morality, and good health tied together in the American public’s attitudes. Certainly, infectious disease and sanitation are directly correlated in many instances, such as in the highly overcrowded and dirty cities in the early twentieth-century United States. Those living in filthy conditions (particularly, lower class individuals) were not only prone to becoming ill, but also considered to be immoral for not practicing proper cleanliness and hygiene. Such perceptions of cleanliness tied to class and morality still remain, as current attitudes about public transit reveal. However, according to various studies, despite the prevalent perception of public transit as filthy and unhealthy, collected specimens show that not as many harmful bacteria reside in the subway as most think. Furthermore, riding the bus or train every day to go to work is actually a great way to be exposed to pathogens in order to build a stronger immune system. In fact, growing health concerns having to do with obesity or other chronic diseases are said to be results of less people using the transit. Therefore, the public perception of cleanliness correlated with health is not quite accurate. This paper explores the current perceptions versus reality of health risks of public transportation in historical context

High-power microstrip switch

Switch, which uses only two p-i-n diodes on microstrip substrate, has been developed for application in spacecraft radio systems. Switch features improved power drain, weight, volume, magnetic cleanliness, and reliability, over currently-used circulator and electromechanical switches

A Computer Vision System to Localize and Classify Wastes on the Streets

Littering quantification is an important step for improving cleanliness of cities. When human interpretation is too cumbersome or in some cases impossible, an objective index of cleanliness could reduce the littering by awareness actions. In this paper, we present a fully automated computer vision application for littering quantification based on images taken from the streets and sidewalks. We have employed a deep learning based framework to localize and classify different types of wastes. Since there was no waste dataset available, we built our acquisition system mounted on a vehicle. Collected images containing different types of wastes. These images are then annotated for training and benchmarking the developed system. Our results on real case scenarios show accurate detection of littering on variant backgrounds

Evaluation of the ground contamination environment for STS payloads

The cleanliness and contamination control requirements for the shuttle program are reviewed. The objectives of the facility verification program are discussed