A test to discover where pupils make mistakes in word problems in algebra

Thesis (Ed.M.)--Boston University, 1947. This item was digitized by the Internet Archive

Report on water supply and distribution, storm and sanitary sewer systems for Longview, Washington

Thesis (Civil Engineering)--University of Kansas, Civil Engineering, 1924

Desperate Measures: How Teacher Preparation Programs can Engage and Retain Black Male Teacher Candidates

Black male teachers are less than two percent of all current teachers in the United States. However, there has been an effort to recruit and retain Black men into the teaching profession for a number of reasons. All student benefit when they have a Black male teacher. Black boys, in particular, have markedly higher test scores and improved discipline when they have a Black male teacher. Black male adults in educational settings is essential for enhancing Black boys’ academic and social development. There is a need for Black male teachers in education. Even with nationwide recruitment efforts like My Brother's Keeper, the numbers of Black male teacher remain small. Additionally, Black male teachers leave the profession at a higher rate than other subgroups. This paper will examine one teacher preparation program's effort to increase retention of Black males in the teacher preparation program and the teaching profession.&nbsp

Theoretical Expectations for Rare and Forbidden Tau Decays

Given the experimental evidence for $\nu_\mu - \nu_\tau$ oscillations, the existence of lepton flavor violation in $\tau$ decays is a theoretical certainty. In this brief review, I consider the connection between models of neutrino mass and the expected observability of some $\tau$ decays.Comment: Talk at TAU 02 (Santa Cruz, CA

Towards Secure and Legal E-Tendering

Tendering processes are considered to be a suitable mechanism for governments to fairly assign contracts for construction projects and procurement. The demand for efficiencies to be created in the process has resulted in a significant number of governments implementing e-tendering systems. E-tendering systems generally involve the submission of tender offer documents to a secure system hosted by the government (principal). An electronic environment presents obvious opportunities for collusion between principal and certain tenderers, fraud by tenderers and a minefield of legal uncertainties for fuelling protracted disputes. Critical examination of the security and legal requirements for e-tendering systems does not appear in the current literature. This paper identifies key security and legal issues to be addressed in the design of e-tendering systems, which may be included in e-procurement software, and proposes a new e-tendering architecture, using distributed trusted third parties which may be suitable for secure large scale operations such as the construction industry

Can a quality improvement project impact maternal and child health outcomes at scale in northern Ghana?

Background Quality improvement (QI) interventions are becoming more common in low- and middle-income countries, yet few studies have presented impact evaluations of these approaches. In this paper, we present an impact evaluation of a scale-up phase of ‘Project Fives Alive!’, a QI intervention in Ghana that aims to improve maternal and child health outcomes. ‘Project Fives Alive!’ employed a QI methodology to recognize barriers to care-seeking and care provision at the facility level and then to identify, test and implement simple and low-cost local solutions that address the barriers. Methods A quasi-experimental design, multivariable interrupted time series analysis, with data coming from 744 health facilities and controlling for potential confounding factors, was used to study the effect of the project. The key independent variables were the change categories (interventions implemented) and implementation phase – Wave 2a (early phase) versus Wave 2b (later phase). The outcomes studied were early antenatal care (ANC), skilled delivery, facility-level under-five mortality and attendance of underweight infants at child welfare clinics. We stratified the analysis by facility type, namely health posts, health centres and hospitals. Results Several of the specific change categories were significantly associated with improved outcomes. For example, three of five change categories (early ANC, four or more ANC visits and skilled delivery/immediate postnatal care (PNC)) for health posts and two of five change categories (health education and triage) for hospitals were associated with increased skilled delivery. These change categories were associated with increases in skilled delivery varying from 28% to 58%. PNC changes for health posts and health centres were associated with greater attendance of underweight infants at child welfare clinics. The triage change category was associated with increased early antenatal care in hospitals. Intensity, the number of change categories tested, was associated with increased skilled delivery in health centres and reduced under-five mortality in hospitals. Conclusions Using an innovative evaluation technique we determined that ‘Project Fives Alive!’ demonstrated impact at scale for the outcomes studied. The QI approach used by this project should be considered by other low- and middle-income countries in their efforts to improve maternal and child health

Predators modify the temperature dependence of life-history trade-offs

Although life histories are shaped by temperature and predation, their joint influence on the interdependence of life-history traits is poorly understood. Shifts in one life-history trait often necessitate shifts in another—structured in some cases by trade-offs— leading to differing life-history strategies among environments. The offspring size–number trade-off connects three traits whereby a constant reproductive allocation (R) constrains how the number (O) and size (S) of offspring change. Increasing temperature and size-independent predation decrease size at and time to reproduction which can lower R through reduced time for resource accrual or size-constrained fecundity. We investigated how O, S, and R in a clonal population of Daphnia magna change across their first three clutches with temperature and size-independent predation risk. Early in ontogeny, increased temperature moved O and S along a trade-off curve (constant R) toward fewer larger offspring. Later in ontogeny, increased temperature reduced R in the no-predator treatment through disproportionate decreases in O relative to S. In the predation treatment, R likewise decreased at warmer temperatures but to a lesser degree and more readily traded off S for O whereby the third clutch showed a constant allocation strategy of O versus S with decreasing R. Ontogenetic shifts in S and O rotated in a counterclockwise fashion as temperature increased and more drastically under risk of predation. These results show that predation risk can alter the temperature dependence of traits and their interactions through trade-offs. Includes supplemental material

Object Segmentation from Motion Discontinuities and Temporal Occlusions–A Biologically Inspired Model

BACKGROUND: Optic flow is an important cue for object detection. Humans are able to perceive objects in a scene using only kinetic boundaries, and can perform the task even when other shape cues are not provided. These kinetic boundaries are characterized by the presence of motion discontinuities in a local neighbourhood. In addition, temporal occlusions appear along the boundaries as the object in front covers the background and the objects that are spatially behind it. METHODOLOGY/PRINCIPAL FINDINGS: From a technical point of view, the detection of motion boundaries for segmentation based on optic flow is a difficult task. This is due to the problem that flow detected along such boundaries is generally not reliable. We propose a model derived from mechanisms found in visual areas V1, MT, and MSTl of human and primate cortex that achieves robust detection along motion boundaries. It includes two separate mechanisms for both the detection of motion discontinuities and of occlusion regions based on how neurons respond to spatial and temporal contrast, respectively. The mechanisms are embedded in a biologically inspired architecture that integrates information of different model components of the visual processing due to feedback connections. In particular, mutual interactions between the detection of motion discontinuities and temporal occlusions allow a considerable improvement of the kinetic boundary detection. CONCLUSIONS/SIGNIFICANCE: A new model is proposed that uses optic flow cues to detect motion discontinuities and object occlusion. We suggest that by combining these results for motion discontinuities and object occlusion, object segmentation within the model can be improved. This idea could also be applied in other models for object segmentation. In addition, we discuss how this model is related to neurophysiological findings. The model was successfully tested both with artificial and real sequences including self and object motion