Interview of Carl Clayton, F.S.C.

Brother Carl Clayton was born George Clayton in 1938, the youngest of four boys, whose family resided in Baltimore, Maryland. He attended Calvert Hall High School and received a scholarship to attend La Salle College in Philadelphia, PA, beginning in September 1956. After a brief time as a student, Mr. Clayton decided to enter the Christian Brothers order. He completed his spiritual and intellectual training and took the name Damian Carl. Eventually his name would change to just Carl. Br. Carl reported to Pittsburg Central Catholic in September 1961 and was later assigned to La Salle High School in 1963. Br. Carl served as vice principal until 1968. Brother Carl would return to La Salle on three different occasions and served as vice principal (1972-77), religion teacher (1986) and guidance counselor. He also served as campus minister at La Salle College (1978-80), California Polytechnic University (1991-94) and St. Mary’s University (mid 1990’s) in Winona, Minnesota. He also served as principal at St. John’s High School in Washington D.C. (1988-91) and oversaw its transition to a coeducational institution. Brother Carl was a member of the Bethlehem University faculty (1998) and returned to serve on the faculties at Hudson Catholic High School (2002-05) and Calvert Hall High School (2005-08). Brother Carl currently lives at the Brothers’ Residence at La Salle High School and is the moderator of the Alumni Association

Design of an Automated Vehicle Detection System for Bicycles: Fireworks Cycling Sensor

Abstract This report explores the necessity for increased cyclist safety in urban settings, leading to the birth of a product which aims to drastically reduce the risk of accidents while heightening the sense of safety overall. The project outlines and details the product development process of a consumer-friendly vehicle detection system, with a holistic scope which includes technical rapid prototyping and coding, team dynamics, decision making process, and change management. Two formal prototypes were developed before a functional final product was identified and constructed, each iteration drastically improving practicality and efficiency of detection. The final product underwent extensive testing in both simulated and natural environments with a maximum range of 45 meters, with a field of view of 1.28 degrees. These parameters were critical in defining the positional angle of the sensor on the bicycle frame. Paired with an LED strip along the top tube of the bicycle frame, the sensor system accurately detects vehicles approaching from the cyclist’s blind spot, and feeds back via the lighting and color of the LED’s to both the cyclist and driver, in both light and dim settings

Simulation Builder, Analysis, and Development (SimBAD) Toolkit for Human Spaceflight Operation Training Using the Spacecraft Simulation Platform

As the scope of human spaceflight continues to expand, the Human Systems Integration (HSI) developed to support complex missions must be robust and efficient. This risk has been outlined in the Human Research Roadmap (HRR) as the “Risk of Adverse Outcomes Due to Inadequate Human Systems Integration Architecture” [1], short name HSIA. One of the most critical elements of any human spaceflight mission is training, which prepares flight operations teams with the resources necessary to carry out that mission. As more distant destinations such as the Moon or Mars are targeted for human spaceflight, ensuring crew have the tools they need to overcome new types of challenges will be a significant focus when developing new training infrastructures. With the nature of such missions, there are several knowledge gaps associated with HSIA that motivate investigating how training should be carried out on such missions. This research focuses on studying these gaps and using the findings to create a conceptual demonstration for a tool that can be used to assist in the training infrastructure that supports future spaceflight missions. This tool is called the Simulation Builder, Analysis, and Development (SimBAD) tool, which is a User Interface (UI) that utilizes the Space Collaborative Real-time Analysis and Flight Toolkit to build virtual training environments. There are four main objectives that incentivize the development of this tool, the improved collaboration between groups in the flight operations team, a training framework that is capable of being packaged on board a spacecraft, a framework that accounts for dynamic mission parameters, and a heightened level of autonomy for crew on missions. These objectives have been driven by the findings from an examination of current spaceflight training methods, previous research on training for future missions, and elements of the HSIA risk that pertain to training. The SimBADtool was designed with features that were motivated by these objectives to effectively create a virtual training facility. These features allow the user to control the environments, systems, procedures, events, and evaluations that are constructed together inside a virtual simulation. Giving this control to users as well as access to the environment through Virtual Reality (VR) is the overall method through which this thesis argues the objectives of the concept are met. These objectives are determined to be met and results for analysis are created through a demonstration of the concept. For this research the demonstration is done through several scenarios that are constructed in simulations using the SimBAD tool. The first is a simulation of IntraVehicular Activities (IVA) procedures being executed on board the International Space Station (ISS) which demonstrates the tool is able to account for dynamic mission parameters; the second is a simulation of two users inside a Mars habitat performing a comms check procedure that demonstrates capability for improved collaboration between groups on the flight operations team. The UI and VR platform demonstrate the tool is capable of packaging on board a spacecraft as well as increasing the autonomy the crew has during their mission. The elements of SimBAD establish a closed-loop infrastructure as a virtual training facility that offers improvements towards human spaceflight in HSI, particularly for future exploration missions by offering functionality towards the construction of simulated scenarios with procedure capability, dynamic event scripting, and simulation evaluation

The oxygen isotope evolution of parent body aqueous solutions as recorded by multiple carbonate generations in the Lonewolf Nunataks 94101 CM2 carbonaceous chondrite

The CM2 carbonaceous chondrite LON 94101 contains aragonite and two generations of calcite that provide snapshots of the chemical and isotopic evolution of aqueous solutions during parent body alteration. Aragonite was the first carbonate to crystallize. It is rare, heterogeneously distributed within the meteorite matrix, and its mean oxygen isotope values are δ18O 39.9±0.6‰, Δ17O -0.3±1.0‰ (1σ). Calcite precipitated very soon afterwards, and following a fall in solution Mg/Ca ratios, to produce small equant grains with a mean oxygen isotope value of δ18O 37.5±0.7‰, Δ17O 1.4±1.1‰ (1σ). These grains were partially or completely replaced by serpentine and tochilinite prior to precipitation of the second generation of calcite, which occluded an open fracture to form a millimeter-sized vein, and replaced anhydrous silicates within chondrules and the matrix. The vein calcite has a mean composition of δ18O 18.4±0.3‰, Δ17O -0.5±0.5‰ (1σ). Petrographic and isotopic results therefore reveal two discrete episodes of mineralization that produced Ca-carbonates with contrasting δ18O, but whose Δ17O values are indistinguishable within error. The aragonite and equant calcite crystallized over a relatively brief period early in the aqueous alteration history of the parent body, and from static fluids that were evolving chemically in response to mineral dissolution and precipitation. The second calcite generation crystallized from solutions of a lower Δ17O, and a lower δ18O and/or higher temperature, which entered LON 9410 via a fracture network. As two generations of calcite whose petrographic characteristics and oxygen isotopic compositions are similar to those in LON 94101 occur in at least one other CM2, multiphase carbonate mineralization could be the typical outcome of the sequence of chemical reactions during parent body aqueous alteration. It is equally possible however that the second generation of calcite in formed in response to an event such as impact fracturing and concomitant fluid mobilisation that affected a large region of the common parent body of several CM2 meteorites. These findings show that integrated petrographic, chemical and isotopic studies can provide new insights into the mechanisms of parent body alteration including the spatial and temporal dynamics of the aqueous system

Fluid evolution in CM carbonaceous chondrites tracked through the oxygen isotopic compositions of carbonates

The oxygen isotopic compositions of calcite grains in four CM carbonaceous chondrites have been determined by NanoSIMS, and results reveal that aqueous solutions evolved in a similar manner between parent body regions with different intensities of aqueous alteration. Two types of calcite were identified in Murchison, Mighei, Cold Bokkeveld and LaPaz Icefield 031166 by differences in their petrographic properties and oxygen isotope values. Type 1 calcite occurs as small equant grains that formed by filling of pore spaces in meteorite matrices during the earliest stages of alteration. On average, the type 1 grains have a δ18O of ∼32–36‰ (VSMOW), and Δ17O of between ∼2‰ and −1‰. Most grains of type 2 calcite precipitated after type 1. They contain micropores and inclusions, and have replaced ferromagnesian silicate minerals. Type 2 calcite has an average δ18O of ∼21–24‰ (VSMOW) and a Δ17O of between ∼−1‰ and −3‰. Such consistent isotopic differences between the two calcite types show that they formed in discrete episodes and from solutions whose δ18O and δ17O values had changed by reaction with parent body silicates, as predicted by the closed-system model for aqueous alteration. Temperatures are likely to have increased over the timespan of calcite precipitation, possibly owing to exothermic serpentinisation. The most highly altered CM chondrites commonly contain dolomite in addition to calcite. Dolomite grains in two previously studied CM chondrites have a narrow range in δ18O (∼25–29‰ VSMOW), with Δ17O ∼−1‰ to −3‰. These grains are likely to have precipitated between types 1 and 2 calcite, and in response to a transient heating event and/or a brief increase in fluid magnesium/calcium ratios. In spite of this evidence for localised excursions in temperature and/or solution chemistry, the carbonate oxygen isotope record shows that fluid evolution was comparable between many parent body regions. The CM carbonaceous chondrites studied here therefore sample either several parent bodies with a very similar initial composition and evolution or, more probably, a single C-type asteroid

Anomalous negative excursion of carbon isotope in organic carbon after the last Paleoproterozoic glaciation in North America

Early Paleoproterozoic time (2.5–2.0 Ga) spanned a critical phase in Earth's history, characterized by repeated glaciations and an increase in atmospheric oxygen (the Great Oxidation Event (GOE)). Following the last and most intense glaciation of this period, marine carbonates record a large positive excursion of δ^(13)C value (termed the “Lomagundi event”) between about 2.2 and 2.1 Ga coinciding with the global appearances of red beds and sulfates, which suggest an accumulation of high levels of atmospheric oxygen. Here we report the discovery of large negative excursions of δ^(13)C in organic matter (down to −55‰) from quartzose sandstones (of the Marquette Range and the Huronian Supergroups, North America) intermediate in age between the last Paleoproterozoic glaciation and the possible onset of the Lomagundi event. The negative excursion is concomitant with the appearance of intensely weathered quartzose sandstones, which may represent hot and humid conditions. There are some interpretations that potentially explain the negative excursions: (1) redeposition of older ^(13)C-depleted kerogen, (2) later post-depositional infiltration of oil, (3) active methane productions by methanogens in shallow-marine environments, or (4) dissociation of methane hydrate. If the latter two were the case, they would provide clues for understanding the environmental change connecting the intense glaciation and an increase in oxygen

Development of flashlamp-pumped Q-switched Ho:Tm:Cr:YAG lasers for mid-infrared LIDAR application

A flashlamp-pumped 2.1 micron Ho:Tm:Cr:YAG laser was studied for both normal mode and Q-switched operations under a wide variety of experimental conditions in order to optimize performance. Laser output energy, slope efficiency, threshold and pulselength were determined as a function of operating temperature, output mirror reflectivity, input electrical energy and Q-switch opening time. The measured normal-mode laser thresholds of a Ho(3+) (0.45 atomic percent):Tm(3+) (2.5 atomic percent):Cr(3+) (0.8 atomic percent):YAG crystal ranged form 26 to 50 J between 120 and 200 K with slope efficiencies up to 0.36 percent with a 60 percent reflective output mirror. Under Q-switched operation the slope efficiency was 90 percent of the normal-mode result. Development of solid state lasers with Ho(3+), Tm(3+) and/or Er(3+) doped crystals has been pursued by NASA for eye-dafe mid-infrared LIDAR (light detection and ranging) application. As a part of the project, the authors have been working on evaluating Ho(3+):Tm(3+):Cr(3+):YAG crystals for normal-mode and Q-switched 2.1 micron laser operations in order to determine an optimum Tm(3+) concentration under flashlamp pumping conditions. Lasing properties of the Ho(3+) in the mid-infrared region have been studied by many research groups since the early 1960's. However, the technology of those lasers is still premature for lidar application. In order to overcome the inefficiency related to narrow absorption bands of the Ho(3+), Tm(3+) and Er(3+), the erbium has been replaced by chromium. The improvement in flashlamp-pumped Ho(3+) laser efficiency has been demonstrated recently by several research groups by utilizing the broad absorption spectrum of Cr(3+) which covers the flashlamp's emission spectrum. Efficient energy transfer to the Tm(3+) and then the Ho(3+) occurs subsequently. It is known that high Tm(3+) concentration and low Ho(3+) concentration are preferred to achieve a quantum efficiency approaching two and to avoid large reabsorption losses. However, determination of the optimum Tm(3+) concentration required to ensure efficient energy transfer from Cr(3+) to Tm(3+) and from Tm(3+) to Ho(3+) has not been made in the Ho:Tm:CR:YAG crystal. The results obtained so far are given