Arithmetic needed in the textile industry

Thesis (M.A.)--Boston University This item was digitized by the Internet Archive

Probe Vehicle Bluetooth Study for Travel Time Savings Estimation

Interstate 69 is a new highway envisioned to eventually travel the length of the United States, from Canada to Mexico. In Indiana, the construction is being completed in a series of segments, as shown below. With the opening of new sections, the travel time savings for travelers can be quantified. By deploying Bluetooth data loggers to capture unique MAC addresses of travelers’ devices, timestamps for corresponding MAC addresses along the study route can be matched to determine travel time. Compared to the posted speeds and lengths of new interstate sections, the travel time saved by using I-69 can be estimated. One such study was completed for the previous opening of I-69 Sections 1-3, and researchers completed a study for Section 4, which opened to public traffic on December 6, 2015

Scalable Dashboard for Identifying Split Failures and Heuristic for Reallocating Split Times

The three fundamental parameters of a traffic signal system are split, cycle, and offset. This paper describes the use of high-resolution data (a) to identify time periods during which split parameters may be insufficient and (b) to help practitioners identify opportunities for reallocating split time. A case study of seven corridors with 47 intersections is presented. A drill-down approach was developed to identify movements that could be improved by a reallocation of split times. A heuristic that can reallocate up to 5 seconds of underutilized green time on a competing phase was applied to those corridors. For the selected phase identified in this study, the adjustment reduced split failures by an average of 40% while also decreasing yellow occupancy an average of 40% and red light violations an average of 66%. The paper concludes by recommending that central systems implement drill-down dashboards. Such tools would enable easy identification and systemwide monitoring of split failures and would provide opportunities to reallocate slack time

Detector-Free Optimization of Traffic Signal Offsets with Connected Vehicle Data

It has recently been shown that signal offset optimization is feasible using vehicle trajectory data at low levels of market penetration. This study performs offset optimization on two corridors using this type ofdata. Six weeks oftrajectory splines were processed for two corridors including 25 signalized intersections, in order to create vehicle arrival profiles, using a proposed procedure called virtual detection. After processing and filtering the data, penetration rates between 0.09-0.80% were observed, varying by approach. The arrival profiles were statistically compared against those measured with physical detectors, with the majority of the approaches showing statistically significant goodness-of-fit at a 90% confidence level. Finally, the virtual detection arrival profiles were used to optimize offsets, and compared against a solution derived from physical detector arrival profiles. The results demonstrate that virtual detection can produce good quality offsets with current market penetration rates of probe data. The study also includes a sensitivity analysis to the sample period, which shows that two weeks of data may be sufficient for data collection at current penetration rates

Real-Time Probe Data Dashboard for Monitoring Detour Route during I-65 N Road Closure

On August 7, 2015, a 37 mile stretch of I-65 N from MM 141 to 178 was closed due to a structural evaluation of a bridge. Traffic was detoured onto US-52, SR-26, and US-231 before returning to the highway. In order to monitor delay and congestion on the detour route, a real-time dashboard was implemented in the style of the interstate Traffic Ticker. Throughout the detour, this website was used to monitor congestion in real time and measure the impact of mitigation actions. The improvement in travel can be seen from the addition of temporary signals, retiming of the US-231 corridor, and conversion of US-231 and SR-18 to a two-way stop

The Universal Stellar Mass-Stellar Metallicity Relation for Dwarf Galaxies

We present spectroscopic metallicities of individual stars in seven gas-rich dwarf irregular galaxies (dIrrs), and we show that dIrrs obey the same mass-metallicity relation as the dwarf spheroidal (dSph) satellites of both the Milky Way and M31: Z_* ∝ M_*^(0.30±0.02). The uniformity of the relation is in contradiction to previous estimates of metallicity based on photometry. This relationship is roughly continuous with the stellar mass-stellar metallicity relation for galaxies as massive as M_* = 10^(12) M_☉. Although the average metallicities of dwarf galaxies depend only on stellar mass, the shapes of their metallicity distributions depend on galaxy type. The metallicity distributions of dIrrs resemble simple, leaky box chemical evolution models, whereas dSphs require an additional parameter, such as gas accretion, to explain the shapes of their metallicity distributions. Furthermore, the metallicity distributions of the more luminous dSphs have sharp, metal-rich cut-offs that are consistent with the sudden truncation of star formation due to ram pressure stripping

Evaluation of Mobile Advanced Road Weather Information Sensor (MARWIS) by Lufft for Indiana Winter Road Operations

The students of the Field Infrastructure Assessment course evaluated the Mobile Advanced Road Weather Information Sensor by Lufft on behalf of the Indiana Department of Transportation. The device is mounted on a vehicle, takes roadway condition measurements 100 times per second, and aggregates the measurements into one-second intervals. The data is transmitted real-time to the cloud. The class specifically evaluated the following measurements: road condition, surface temperature, and friction. It was found that the MARWIS temperature reading was systematically 4˚F lower than the probe readings. Skid test empirical results were consistent with the MARWIS friction readings. It was also found, using two devices on the back of the test vehicle, that the friction in the wheel track was greater than the friction in the center of the lane, as expected. Lastly, the “chemically wet” road condition was not consistently observed by MARWIS where expected

Wildlife-friendly farming increases crop yield: evidence for ecological intensification

Ecological intensification has been promoted as a means to achieve environmentally sustainable increases in crop yields by enhancing ecosystem functions that regulate and support production. There is, however, little direct evidence of yield benefits from ecological intensification on commercial farms growing globally important foodstuffs (grains, oilseeds and pulses). We replicated two treatments removing 3 or 8% of land at the field edge from production to create wildlife habitat in 50–60 ha patches over a 900 ha commercial arable farm in central England, and compared these to a business as usual control (no land removed). In the control fields, crop yields were reduced by as much as 38% at the field edge. Habitat creation in these lower yielding areas led to increased yield in the cropped areas of the fields, and this positive effect became more pronounced over 6 years. As a consequence, yields at the field scale were maintained—and, indeed, enhanced for some crops—despite the loss of cropland for habitat creation. These results suggested that over a 5-year crop rotation, there would be no adverse impact on overall yield in terms of monetary value or nutritional energy. This study provides a clear demonstration that wildlife-friendly management which supports ecosystem services is compatible with, and can even increase, crop yields