Effect of Distance to Orthogonal Buffer Zone Boundary on Contaminant Detection Well Layout at Solid Waste Impoundment

A modeling investigation examined the effect of nearby buffer zone (property) boundaries on passive groundwater monitoring networks at a hypothetical landfill. Network designs considered the unknown location of a small point source in the landfill's liner, contaminant concentrations simulated in groundwater, and the need to detect a contaminant before its concentration at a buffer zone boundary reached a certain threshold. Several buffer zone boundaries were considered, ranging from 6 m to 51 m downgradient of the landfill's downgradient corner. Monitoring wells in each network were located 5 m downgradient of the landfill's downgradient boundaries. Both the minimum number of wells, and the rate of increase in number of wells, increased with proximity of the landfill's downgradient corner to the buffer zone boundary. Based on out-comes of this study, landfill designers should consider a possible need for many closely-spaced detection wells for small potential point sources and close buffer zone boundaries.

Comments on Kathrin Koslicki’s “Essence and Identity”

Kathrin Koslicki’s chapter is a wonderfully bold and innovative attack on the question of crossworld-identity: Quine thought Aristotelian essentialism was the problem; and she takes Aristotelian hylomorphism to be the solution. Let me begin with a small point. Koslicki takes a criterion of crossworld identity to be a criterion for when an entity y...

Reading the Nicomachean Ethics as an Investigation

Aristotle tells us that the Nicomachean Ethics is an “inquiry” and an “investigation” (methodos and zētēsis). This paper focuses on an under-appreciated way that the work is investigative: its employment of an exploratory investigative strategy—that is, its frequent positing of, and later revision or even rejection of, merely preliminary positions. Though this may seem like a small point, this aspect of the work’s methodology has important consequences for how we should read it—specifically, we should be open to the possibility that some contradictions in the text are the result of his employment of this investigative strategy. In the paper, I describe this investigative strategy, discuss what motivates Aristotle to employ it in the work, and go through three contradictions that are plausibly identified as examples of its use—specifically, his claims that courageous people do and do not fear death, that friendship is and is not mutually recognized goodwill, and that virtuous people do and do not choose noble actions for their own sake.

Comparative analysis of segmentation algorithms for the allocation of microcalcifications on mammograms

Breast cancer is the most common disease of the current century in the female population of the world. The main task of the research of most scientists is the detection of this pathology at an early stage (the tumor size is less than 7 mm) when a woman can still be helped. An indicator of this disease is the presence of small-point microcalcifications, located in groups within or in the immediate circle of the tumor. Microcalcification is a small-point character at cancer, reminding grains of sand of irregular shape which sizes are from 100 to 600 microns. The probability of breast cancer increases with the increase in the number of microcalcifications per unit area. So, the probability of cancer is 80% if more than 15 microcalcifications on 1 sq. cm. The microcalcifications are often the only sign of breast cancer, therefore, their detection even in the absence of a tumor node could be a harbinger to cancer. Image segmentation is one way to identify microcalcifications. The conducted research allowed us to choose the optimal segmentation algorithms of mammograms to highlight areas of microcalcifications for further analysis of their groups, sizes, and so on.

Positive Breakdown Streamers and Acceleration in a Small Point-Plane Liquid Gap and Their Variation with Liquid Properties.

<p>Positive breakdown streamers have been investigated in a short (5 mm) point-plane gap in cyclohexane and n-tridecane with and without the additives N,N-dimethylamine (DMA) with low ionization potential and azobenzene with a not quite as low ionization potential but a very low lowest excitation level. The effects off additives are fairly similar to what is known from longer gaps with DMA or pyrene added: the additives caused reduced breakdown voltage, significantly increased acceleration voltage and increased streamer velocity around breakdown. Molecule for molecule, azobenzene has less effect than DMA. The ratio between the acceleration and the breakdown voltage is significantly higher than in long gaps, though. Nonetheless, tests in short gaps are sufficiently good for screening (a large number of) liquid combinations.<br />The two base liquids without additives, and also neat trichloroethene and DMA have been tested with and without a tube causing spatial restriction of the streamer. Restriction causes increased breakdown voltage and promotes the fastest streamer modes.</p>