1,778 research outputs found
Collaborative Leadership and the Design of a School-Based Chemical Health Service System
This work-related project used strategies of collaborative leadership behavior to facilitate the design and implementation of a county-wide, comprehensive, and coordinated school-based chemical health service system. People involved in the design included representatives from school districts, county government departments, chemical dependency treatment agencies, nonprofit organizations, and a parent. The goal of this project was to create an effective, sustainable, and cohesive collaboration through the use of a facilitation process that illustrated the principles of collaborative leadership. The project demonstrated that interagency collaboration, along with effective leadership skills, can be successful in achieving meaningful system change that benefits adolescents and their families
Mass transport during coagulation of cellulose-ionic liquid solutions in different non-solvents
Cellulose can be regenerated from cellulose-ionic liquid (IL) solutions by immersion in water or alcohols. These compounds are potent non-solvents due to their proton-donating ability in hydrogen bonds to IL anions. Although they share this fundamental way of reducing IL solvent quality, coagulation in water is distinctly different from coagulation in alcohols with regard to the microstructures formed and the mechanisms that generate the microstructures. In this study, the possibility of mass-transport effects on microstructures was investigated. The mass-transport of all components: non-solvent (EtOH, 2PrOH), IL ([C2mim][OAc]), and a co-solvent (DMSO), during coagulation was studied. The data was compared to previous data with water as the non-solvent. Results showed that diffusion is essentially limited to a continuous non-solvent-rich phase that is formed during phase separation in all non-solvents. There were also significant differences between non-solvents. For instance, [C2mim][OAc] diffusion coefficients were 6–9 times smaller in 2PrOH than in water, and there were apparent effects from cellulose concentration in 2PrOH that were not observed in water. The differences stem from the interactions between solvent, non-solvents, and cellulose, which can be both mutual and competitive. Weaker [C2mim][OAc]-non-solvent interactions with alcohols give more persistent [C2mim][OAc]-cellulose interactions than with water as the non-solvent, which has consequences for mass-transport. Graphic abstract: [Figure not available: see fulltext.]
The Use of DISC Behavioral Profiling and Training: An Innovative Pedagogical Strategy to Enhance Learning and Future Career Opportunities in Sport Management and Sport Coaching Higher Education Classrooms
Implementing effective training and education programs is of critical importance for sport management and sport coaching academic education programs. This exploratory ÂÂÂÂÂresearch examined the implementation and effectiveness of DISC behavioral profiling in sport management and sport coaching classrooms at the university level. Over four academic years (eight semesters), pre- and post-tests were collected from multiple samples of sport management and sport coaching students (N = 216) at two universities in the United States. Students received a personalized DISC behavioral profile and educational activities were used to enhance the value of the behavioral profiling initiatives. Using pre- and post-activity surveys of the knowledge and skills gained during in-course activities, paired sample t-test showed positive and significant results for 11 of 16 measured areas. The findings suggest that behavioral profiling tools and activities within sport management and sport coaching curricula can enhance student’s self-awareness and help develop leadership skills which will prepare for future career opportunities. Limitations and opportunities for future research are also presented
Large Steel Tank Fails and Rockets to Height of 30 meters - Rupture Disc Installed Incorrectly
AbstractAt a brewery, the base plate-to-shell weld seam of a 90-m3 vertical cylindrical steel tank failed catastrophically. The 4 ton tank “took off” like a rocket leaving its contents behind, and landed on a van, crushing it. The top of the tank reached a height of 30 m. The internal overpressure responsible for the failure was an estimated 60 kPa. A rupture disc rated at < 50 kPa provided overpressure protection and thus prevented the tank from being covered by the European Pressure Equipment Directive. This safeguard failed and it was later discovered that the rupture disc had been installed upside down. The organizational root cause of this incident may be a fundamental lack of appreciation of the hazards of large volumes of low-pressure compressed air or gas. A contributing factor may be that the standard piping and instrumentation diagram (P&ID) symbol for a rupture disc may confuse and lead to incorrect installation. Compressed air systems are ubiquitous. The medium is not toxic or flammable. Such systems however, when operated at “slight overpressure” can store a great deal of energy and thus constitute a hazard that ought to be addressed by safety managers
Compact, Deep-Penetrating Geothermal Heat Flow Instrumentation for Lunar Landers
Geothermal heat flow is obtained as a product of the two separate measurements of geothermal gradient in, and thermal conductivity of, the vertical soi/rock/regolith interval penetrated by the instrument. Heat flow measurements are a high priority for the geophysical network missions to the Moon recommended by the latest Decadal Survey [I] and previously the International Lunar Network [2]. The two lunar-landing missions planned later this decade by JAXA [3] and ESA [4] also consider geothermal measurements a priority
Development of a Compact, Deep-Penetrating Heat Flow Instrument for Lunar Landers: In-Situ Thermal Conductivity System
Geothermal heat flow is obtained as a product of the geothermal gradient and the thermal conductivity of the vertical soil/rock/regolith interval penetrated by the instrument. Heat flow measurements are a high priority for the geophysical network missions to the Moon recommended by the latest Decadal Survey and previously the International Lunar Network. One of the difficulties associated with lunar heat flow measurement on a robotic mission is that it requires excavation of a relatively deep (approx 3 m) hole in order to avoid the long-term temporal changes in lunar surface thermal environment affecting the subsurface temperature measurements. Such changes may be due to the 18.6-year-cylcle lunar precession, or may be initiated by presence of the lander itself. Therefore, a key science requirement for heat flow instruments for future lunar missions is to penetrate 3 m into the regolith and to measure both thermal gradient and thermal conductivity. Engineering requirements are that the instrument itself has minimal impact on the subsurface thermal regime and that it must be a low-mass and low-power system like any other science instrumentation on planetary landers. It would be very difficult to meet the engineering requirements, if the instrument utilizes a long (> 3 m) probe driven into the ground by a rotary or percussive drill. Here we report progress in our efforts to develop a new, compact lunar heat flow instrumentation that meets all of these science and engineering requirements
Improved Data Reduction Algorithm for the Needle Probe Method Applied to In-Situ Thermal Conductivity Measurements of Lunar and Planetary Regoliths
The needle probe method (also known as the' hot wire' or 'line heat source' method) is widely used for in-situ thermal conductivity measurements on soils and marine sediments on the earth. Variants of this method have also been used (or planned) for measuring regolith on the surfaces of extra-terrestrial bodies (e.g., the Moon, Mars, and comets). In the near-vacuum condition on the lunar and planetary surfaces, the measurement method used on the earth cannot be simply duplicated, because thermal conductivity of the regolith can be approximately 2 orders of magnitude lower. In addition, the planetary probes have much greater diameters, due to engineering requirements associated with the robotic deployment on extra-terrestrial bodies. All of these factors contribute to the planetary probes requiring much longer time of measurement, several tens of (if not over a hundred) hours, while a conventional terrestrial needle probe needs only 1 to 2 minutes. The long measurement time complicates the surface operation logistics of the lander. It also negatively affects accuracy of the thermal conductivity measurement, because the cumulative heat loss along the probe is no longer negligible. The present study improves the data reduction algorithm of the needle probe method by shortening the measurement time on planetary surfaces by an order of magnitude. The main difference between the new scheme and the conventional one is that the former uses the exact mathematical solution to the thermal model on which the needle probe measurement theory is based, while the latter uses an approximate solution that is valid only for large times. The present study demonstrates the benefit of the new data reduction technique by applying it to data from a series of needle probe experiments carried out in a vacuum chamber on JSC-1A lunar regolith stimulant. The use of the exact solution has some disadvantage, however, in requiring three additional parameters, but two of them (the diameter and the volumetric heat capacity of the probe) can be measured and the other (the volumetric heat capacity of the regolith/stimulant) may be estimated from the surface geologic observation and temperature measurements. Therefore, overall, the new data reduction scheme would make in-situ thermal conductivity measurement more practical on planetary missions
Development of Compact, Modular Lunar Heat Flow Probes
Geothermal heat flow measurements are a high priority for the future lunar geophysical network missions recommended by the latest Decadal Survey and previously the International Lunar Network. Because the lander for such a mission will be relatively small, the heat flow instrumentation must be a low-mass and low-power system. The instrument needs to measure both thermal gradient and thermal conductivity of the regolith penetrated. It also needs to be capable of excavating a deep enough hole (approx. 3 m) to avoid the effect of potential long-term changes of the surface thermal environment. The recently developed pneumatic excavation system can largely meet the low-power, low-mass, and the depth requirements. The system utilizes a stem which winds out of a pneumatically driven reel and pushes its conical tip into the regolith. Simultaneously, gas jets, emitted from the cone tip, loosen and blow away the soil. The thermal sensors consist of resistance temperature detectors (RTDs) embedded on the stem and an insitu thermal conductivity probe attached to the cone tip. The thermal conductivity probe consists of a short 'needle' (2.4-mm diam. and 15- to 20-mm length) that contains a platinum RTD wrapped in a coil of heater wire. During a deployment, when the penetrating cone reaches a desired depth, it stops blowing gas, and the stem pushes the needle into the yet-to-be excavated, undisturbed bottom soil. Then, it begins heating and monitors the temperature. Thermal conductivity of the soil can determined from the rate of temperature increase with time. When the measurement is complete, the system resumes excavation until it reaches the next targeted depth
Characterisation of spatial network-like patterns from junctions' geometry
We propose a new method for quantitative characterization of spatial
network-like patterns with loops, such as surface fracture patterns, leaf vein
networks and patterns of urban streets. Such patterns are not well
characterized by purely topological estimators: also patterns that both look
different and result from different morphogenetic processes can have similar
topology. A local geometric cue -the angles formed by the different branches at
junctions- can complement topological information and allow to quantify the
large scale spatial coherence of the pattern. For patterns that grow over time,
such as fracture lines on the surface of ceramics, the rank assigned by our
method to each individual segment of the pattern approximates the order of
appearance of that segment. We apply the method to various network-like
patterns and we find a continuous but sharp dichotomy between two classes of
spatial networks: hierarchical and homogeneous. The first class results from a
sequential growth process and presents large scale organization, the latter
presents local, but not global organization.Comment: version 2, 14 page
Violent explosion after inadvertent mixing of nitric acid and isopropanol – Review 15 years later finds basic accident data corrupted, no evidence of broad learning
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