518 research outputs found
Academic Dishonesty and Testing: How Student Beliefs and Test Settings Impact Decisions to Cheat
Research shows that academic dishonesty in post-secondary education runs particularly high among students in the specific disciplines of engineering, business, and nursing. The authors were interested in how student attitudes towards specific environments for testing might contribute to the prevalence or likelihood of cheating on tests and exams. It was hypothesized that while there would be no difference in their beliefs or attitudes regarding the acceptability of cheating behaviors in unproctored versus proctored settings, students would be more likely to engage in cheating behavior in an unproctored setting. Technology continues to transform the world around us at a rapid pace, allowing faculty to incorporate more technology into the classroom and to educate more students remotely via hybrid and online classes. While these opportunities have their benefits, they also present new challenges. The opportunity for cheating on tests increases, especially when exams are delivered in unproctored environments. An instrument was created to investigate the attitudes and behaviors of first- and second-year undergraduate engineering students while taking tests in both proctored and unproctored environments. In all, 734 students were surveyed from four different institutions of higher education. Students provided both qualitative and quantitative responses to questions related to their beliefs and attitudes toward cheating in todayâs socially shareable society. Results indicated that both studentsâ attitudes and behaviors vary as a result of tests being delivered in a proctored versus unproctored environment
Test Proctors Share All: Stories From The Frontlines of Testing
A compilation of test proctor stories from testing centers around the United States and across the globe. Proctors reveal the day to day realities of being on the frontlines of test fraud mitigation in an ever increasing digitally shareable society
Trading Robustness Requirements in Mars Entry Trajectory Design
One of the most important metrics characterizing an atmospheric entry trajectory in preliminary design is the size of its predicted landing ellipse. Often, requirements for this ellipse are set early in design and significantly influence both the expected scientific return from a particular mission and the cost of development. Requirements typically specify a certain probability level (6-level) for the prescribed ellipse, and frequently this latter requirement is taken at 36. However, searches for the justification of 36 as a robustness requirement suggest it is an empirical rule of thumb borrowed from non-aerospace fields. This paper presents an investigation into the sensitivity of trajectory performance to varying robustness (6-level) requirements. The treatment of robustness as a distinct objective is discussed, and an analysis framework is presented involving the manipulation of design variables to effect trades between performance and robustness objectives. The scenario for which this method is illustrated is the ballistic entry of an MSL-class Mars entry vehicle. Here, the design variable is entry flight path angle, and objectives are parachute deploy altitude performance and error ellipse robustness. Resulting plots show the sensitivities between these objectives and trends in the entry flight path angles required to design to these objectives. Relevance to the trajectory designer is discussed, as are potential steps for further development and use of this type of analysis
Influence du climat et des traitements de potabilisation sur l'oxydabilité d'une eau en cours d'affinage
La matiĂšre organique prĂ©sente dans une eau clarifiĂ©e et ozonĂ©e puis filtrĂ©e sur charbon a Ă©tĂ© caractĂ©risĂ©e durant 8 mois par l'oxydabilitĂ© au KMnO4 Ă chaud et en milieu acide; on a relevĂ© les paramĂštres climatiques et notĂ© les traitements de potabilisation appliquĂ©s.Une analyse en composantes principales suivie d'une analyse discriminante effectuĂ©e sur 129 prĂ©lĂšvements fait ressortir que deux paramĂštres - la tempĂ©rature et le pH - suffisent Ă classer ces eaux en 3 groupes : chacun d'eux correspond Ă une saison, avec un pourcentage d'erreur de 6 %.En moyenne, l'oxydabititĂ© de l'eau Ă l'entrĂ©e du filtre ne varie pas d'une saison Ă l'autre; mais la dispersion des valeurs est plus importante au printemps. La politique de traitement appliquĂ©e n'apparaĂźt pas clairement. Des analyses de variance suivies de rĂ©gressions linĂ©aires multiples montrent que cette oxydabilitĂ© dĂ©pend Ă la fois de la sĂ©quence et du traitement d'ozonation : moins de 30 % de La variance se trouvent ainsi expliquĂ©s.La filtration sur charbon Ă 5 m.h-1 abaisse l'oxydabilitĂ© de G Ă 0,8 mg O2 par litre et diminue sa variabilitĂ©. On note cependant des relargages en fin de printemps lors du rĂ©Ă©quilibrage du filtre. L'oxydabilitĂ© de l'eau filtrĂ©e dĂ©pend Ă la fois de celle mesurĂ©e Ă l'entrĂ©e du filtre et de la tempĂ©rature : les modĂšles retenus, dĂ©terminĂ©s par rĂ©gression linĂ©aire multiple, diffĂšrent d'une saison Ă l'autre, indiquant un fonctionnement diffĂ©rent du rĂ©acteur. Il est alors possible de dĂ©finir des pĂ©riodes oĂč elle est minimale.La qualitĂ© d'une eau affinĂ©e varie ainsi avec les saisons, ceci malgrĂ© un lissage dĂ» aux effets des traitements appliquĂ©s en amont.Oxidizability by KMnO4 in a hot acidic medium was used for 8 months to estimate organic matter in clarified-ozonized then GAC-filtered waters, treated on a pilot plant (Figure 1).Flowrate of the River Seine (DEB), temperature (TEM), pH (PHE) and oxidizability of the waters before GAC-filtration (OXE) are shown to vary with time (Figures 2 to 5). The first two parameters are generally used to classify raw waters but here they are not enough (Figure 6). Then, multivariate statistical analyses - principal component analysis and discriminant analysis - are carried out on 129 samples : they show (Figure 7) that two parameters, one in connection with climate only - temperature - and the other in connection with both climate and treatments - pH - are able to classify these waters into three groups equivalent to three seasons; the error coefficient is of 6 % only. Seasonal characteristics of these waters are given in Table 1. Average values of oxidizability (OXE) do not vary with the seasons, but standard-deviation is the greatest in Spring.There is no apparent connection between the different treatments - preozonation level (PO3), quantity of flocculant added (WAC), land-filtration velocity (VFS), ozonation level (O3F), residual ozone level (O3R), GAC-filtration flowrate (DAL) - except between the two ozonation treatments (Figure 3). Their seasonal variations are given in Table 2.Variance analyses show that the 3 factors, quantity of floccutant (WAC), sand-filtration velocity (VFS) and absence of preozonation (PO3), have no effect upon the oxidizability of the water supptying the GAC-filter (OXE). This parameter is a function of preozonation (PO3), interozonation (O3F) and residual ozone levels (O3R) and sequency (SEQ) : the models achieved, determined by linear multiple regression, account for less than 30 % of the variance (Figure 9).The GAC-filtration at 5 m.h-1 diminishes the oxidizability values of zero to 0.8 mg O2l-1 and their variability; however, some releases appear at the end of Spring, during the re-equilibration phase of the filter (Figure 10). By linear multiple regression, we can express the oxidizability of the filtered waters (OXS) as a function of (OXE) and temperature (TEM). The models achieved differ from one season to another (Figure 11) and account for 32 to 73 % of the variance; thus the working of the GAC-filter is dependent on the seasons.Many authors assume that the risk of bacterial regrowth in the distribution network is minimal when the oxidizability of the treated waters is minimal. Here, the oxidizability of the filtered waters (OXS) is at its lowest when temperature (TEM) and (OXE) are lowest (Figures 12 and 13). These conditions are often met in the middle of the seasons, when the quantity and the quality of the organic matter vary little; the fitter is then balanced.The quality of a treated water therefore varies with the seasons, despite polishing obtained through treatments applied upstream, which tend to improve it and diminish its variability
Angle of Attack Modulation for Mars Entry Terminal State Optimization
From the perspective of atmospheric entry, descent, and landing (EDL), one of the most foreboding destinations in the solar system is Mars due in part to its exceedingly thin atmosphere. To benchmark best possible scenarios for evaluation of potential Mars EDL system designs, a study is conducted to optimize the entry-to-terminal-state portion of EDL for a variety of entry velocities and vehicle masses, focusing on the identification of potential benefits of enabling angle of attack modulation. The terminal state is envisioned as one appropriate for the initiation of terminal descent via parachute or other means. A particle swarm optimizer varies entry flight path angle, ten bank profile points, and ten angle of attack profile points to find maximum-final-altitude trajectories for a 10 30 m ellipsled at 180 different combinations of values for entry mass, entry velocity, terminal Mach number, and minimum allowable altitude. Parametric plots of maximum achievable altitude are shown, as are examples of optimized trajectories. It is shown that appreciable terminal state altitude gains (2.5-4.0 km) over pure bank angle control may be possible if angle of attack modulation is enabled for Mars entry vehicles. Gains of this magnitude could prove to be enabling for missions requiring high-altitude landing sites. Conclusions are also drawn regarding trends in the bank and angle of attack profiles that produce the optimal trajectories in this study, and directions for future work are identified
Post-polymerization functionalization of poly (ethylene oxide)âpoly (ÎČ-6-heptenolactone) diblock copolymers to tune properties and self-assembly
Polyester-based amphiphilic block copolymers and their nanoassemblies are of significant interest for a wide range of applications due to the degradability of the polyester block. However, the commonly used polyesters lack functional groups on their backbones, limiting the possibilities to chemically modify these polymers. Described here are new poly(ethylene oxide) (PEO)âpoly(ÎČ-6-heptenolactone) (PHEL) block copolymers having pendant alkenes at each repeat unit on the PHEL block. First, the self-assembly of these block copolymers in aqueous solution was studied and it was found that they formed solid nanoparticles and vesicles depending on the relative block lengths. Next the alkene moieties of the block copolymer were modified with either hydrophilic or hydrophobic pendant groups using thiolâene reactions, allowing the hydrophilic mass fractions and consequently the self-assembled morphologies to be tuned, accessing both smaller nanoparticles and cylindrical assemblies. It was also demonstrated that the anti-cancer drug paclitaxel or a fluorescent rhodamine dye could be easily conjugated to the block copolymers and the self-assembly of these conjugates was explored. Overall, the results of this study demonstrate that PEO-PHEL block copolymers can serve as versatile backbones for the preparation of functional, polyester-based materials
Post-polymerization functionalization of poly(ethylene oxide)âpoly(ÎČ-6-heptenolactone) diblock copolymers to tune properties and self-assembly
Copolymers were synthesized and functionalized with a variety of moieties to tune self-assembly and install drugs or fluorescent dyes. , Polyester-based amphiphilic block copolymers and their nanoassemblies are of significant interest for a wide range of applications due to the degradability of the polyester block. However, the commonly used polyesters lack functional groups on their backbones, limiting the possibilities to chemically modify these polymers. Described here are new poly(ethylene oxide) (PEO)âpoly(ÎČ-6-heptenolactone) (PHEL) block copolymers having pendant alkenes at each repeat unit on the PHEL block. First, the self-assembly of these block copolymers in aqueous solution was studied and it was found that they formed solid nanoparticles and vesicles depending on the relative block lengths. Next the alkene moieties of the block copolymer were modified with either hydrophilic or hydrophobic pendant groups using thiolâene reactions, allowing the hydrophilic mass fractions and consequently the self-assembled morphologies to be tuned, accessing both smaller nanoparticles and cylindrical assemblies. It was also demonstrated that the anti-cancer drug paclitaxel or a fluorescent rhodamine dye could be easily conjugated to the block copolymers and the self-assembly of these conjugates was explored. Overall, the results of this study demonstrate that PEO-PHEL block copolymers can serve as versatile backbones for the preparation of functional, polyester-based materials
Quantum algorithms for connectivity and related problems
An important family of span programs, st-connectivity span programs, have been used to design quantum algorithms in various contexts, including a number of graph problems and formula evaluation problems. The complexity of the resulting algorithms depends on the largest positive witness size of any 1-input, and the largest negative witness size of any 0-input. Belovs and Reichardt first showed that the positive witness size is exactly characterized by the effective resistance of the input graph, but only rough upper bounds were known previously on the negative witness size. We show that the negative witness size in an st-connectivity span program is exactly characterized by the capacitance of the input graph. This gives a tight analysis for algorithms based on st-connectivity span programs on any set of inputs. We use this analysis to give a new quantum algorithm for estimating the capacitance of a graph. We also describe a new quantum algorithm for deciding if a graph is connected, which improves the previous best quantum algorithm for this problem if we're promised that either the graph has at least k > 1 components, or the graph is connected and has small average resistance, which is upper bounded by the diameter. We also give an alternative algorithm for deciding if a graph is connected that can be better than our first algorithm when the maximum degree is small. Finally, using ideas from our second connectivity algorithm, we give an algorithm for estimating the algebraic connectivity of a graph, the second largest eigenvalue of the Laplacian
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