Quantum-accelerated constraint programming

Constraint programming (CP) is a paradigm used to model and solve constraint satisfaction and combinatorial optimization problems. In CP, problems are modeled with constraints that describe acceptable solutions and solved with backtracking tree search augmented with logical inference. In this paper, we show how quantum algorithms can accelerate CP, at both the levels of inference and search. Leveraging existing quantum algorithms, we introduce a quantum-accelerated filtering algorithm for the $\texttt{alldifferent}$ global constraint and discuss its applicability to a broader family of global constraints with similar structure. We propose frameworks for the integration of quantum filtering algorithms within both classical and quantum backtracking search schemes, including a novel hybrid classical-quantum backtracking search method. This work suggests that CP is a promising candidate application for early fault-tolerant quantum computers and beyond.Comment: published in Quantu

Examining EdD Dissertations in Practice: The Carnegie Project on the Education Doctorate

In 2007, 25 colleges and schools of education (Phase I) came together under the aegis of the Carnegie Project on the Education Doctorate (CPED) to transform doctoral education for education practitioners. A challenging aspect of the reform of the educational doctorate is the role and design of the dissertation or Dissertation in Practice. In response to consortium concerns, members of the CPED Dissertation in Practice Awards Committee conducted this action research study to examine the format and design of Dissertations in Practice submitted by (re) designed programs. Data were gathered with an online survey, interviews, analyses of 25 Dissertations in Practice submitted in 2013 to the Committee. Results indicated few changes occurred in the final product, despite evidence of change in the Dissertation in Practice process. Findings contribute to debates about the distinctive nature of EdDs (and of professional doctorates generally) as distinct from PhDs, and how about the key criteria for demonstrating “new knowledge to solve significant problems of practice” are demonstrated through the dissertation submission

Engaging Students With Course Content Using Scheduled and Unscheduled Emails and Text Messages

This study addressed college students’ acceptance of push communication (i.e., email and SMS messaging) as a means of receiving course-related content, and modified the Unified Theory of Acceptance and Use of Technology by including Scheduled Message as an independent variable. Surveys of 301 students’ perceptions of instructor-sent email and SMS texts directing them to materials in six instructors’ 10 courses were analyzed by PLS-PM for their impact on the students’ intention to use these push communication technologies. In contrast to previous studies on technology acceptance, we evaluated actual usage patterns for both the scheduled and unscheduled push communication. Scheduled emails did not yield higher average duration times or unique visitors than unscheduled ones, yet click-through rates and return visits were higher. Scheduled SMS messages did yield higher average duration times, unique visitors, and click-through rates than unscheduled SMS messages, yet unscheduled SMS messages yielded more return visits. We argue that the differences in the results for email vs. SMS may have been due to email’s slower delivery time. We also consider implications for faculty wishing to facilitate distributed learning among students via push communication

Engaging Students With Course Content Using Scheduled and Unscheduled Emails and Text Messages

This study addressed college students’ acceptance of push communication (i.e., email and SMS messaging) as a means of receiving course-related content, and modified the Unified Theory of Acceptance and Use of Technology by including Scheduled Message as an independent variable. Surveys of 301 students’ perceptions of instructor-sent email and SMS texts directing them to materials in six instructors’ 10 courses were analyzed by PLS-PM for their impact on the students’ intention to use these push communication technologies. In contrast to previous studies on technology acceptance, we evaluated actual usage patterns for both the scheduled and unscheduled push communication. Scheduled emails did not yield higher average duration times or unique visitors than unscheduled ones, yet click-through rates and return visits were higher. Scheduled SMS messages did yield higher average duration times, unique visitors, and click-through rates than unscheduled SMS messages, yet unscheduled SMS messages yielded more return visits. We argue that the differences in the results for email vs. SMS may have been due to email’s slower delivery time. We also consider implications for faculty wishing to facilitate distributed learning among students via push communication

SKITTER/implement mechanical interface

SKITTER (Spacial Kinematic Inertial Translatory Tripod Extremity Robot) is a three-legged transport vehicle designed to perform under the unique environment of the moon. The objective of this project was to design a mechanical interface for SKITTER. This mechanical latching interface will allow SKITTER to use a series of implements such as drills, cranes, etc., and perform different tasks on the moon. The design emphasized versatility and detachability; that is, the interface design is the same for all implements, and connection and detachment is simple. After consideration of many alternatives, a system of three identical latches at each of the three interface points was chosen. The latching mechanism satisfies the design constraints because it facilitates connection and detachment. Also, the moving parts are protected from the dusty environment by housing plates

Lunar crane hook

The base and ball hook system is an attachment that is designed to be used on the lunar surface as an improved alternative to the common crane hook and eye system. The design proposed uses an omni-directional ball hook and base to overcome the design problems associated with a conventional crane hook. The base and ball hook is not sensitive to cable twist which would render a robotic lunar crane useless since there is little atmospheric resistance to dampen the motion of an oscillating member. The symmetric characteristics of the ball hook and base eliminates manual placement of the ball hook into the base; commonly associated with the typical hook and eye stem. The major advantage of the base and ball hook system is it's ease of couple and uncouple modes that are advantages during unmanned robotic lunar missions

LoCuSS: The Sunyaev-Zel'dovich Effect and Weak Lensing Mass Scaling Relation

We present the first weak-lensing-based scaling relation between galaxy cluster mass, M_wl, and integrated Compton parameter Y_sph. Observations of 18 galaxy clusters at z~0.2 were obtained with the Subaru 8.2-m telescope and the Sunyaev-Zel'dovich Array. The M_wl-Y_sph scaling relations, measured at Delta=500, 1000, and 2500 rho_c, are consistent in slope and normalization with previous results derived under the assumption of hydrostatic equilibrium (HSE). We find an intrinsic scatter in M_wl at fixed Y_sph of 20%, larger than both previous measurements of M_HSE-Y_sph scatter as well as the scatter in true mass at fixed Y_sph found in simulations. Moreover, the scatter in our lensing-based scaling relations is morphology dependent, with 30-40% larger M_wl for undisturbed compared to disturbed clusters at the same Y_sph at r_500. Further examination suggests that the segregation may be explained by the inability of our spherical lens models to faithfully describe the three-dimensional structure of the clusters, in particular, the structure along the line-of-sight. We find that the ellipticity of the brightest cluster galaxy, a proxy for halo orientation, correlates well with the offset in mass from the mean scaling relation, which supports this picture. This provides empirical evidence that line-of-sight projection effects are an important systematic uncertainty in lensing-based scaling relations.Comment: Accepted versio

Resting pulmonary haemodynamics and shunting: a comparison of sea-level inhabitants to high altitude Sherpas

The incidence of blood flow through intracardiac shunt and intrapulmonary arteriovenous anastomoses (IPAVA) may differ between Sherpas permanently residing at high altitude (HA) and sea-level (SL) inhabitants as a result of evolutionary pressure to improve gas exchange and/or resting pulmonary haemodynamics. To test this hypothesis we compared sea-level inhabitants at SL (SL-SL; n = 17), during acute isocapnic hypoxia (SL-HX; n = 7) and following 3 weeks at 5050 m (SL-HA; n = 8 non-PFO subjects) to Sherpas at 5050 m (n = 14). inline image, heart rate, pulmonary artery systolic pressure (PASP) and cardiac index (Qi) were measured during 5 min of room air breathing at SL and HA, during 20 min of isocapnic hypoxia (SL-HX; inline image = 47 mmHg) and during 5 min of hyperoxia (inline image = 1.0; Sherpas only). Intracardiac shunt and IPAVA blood flow was evaluated by agitated saline contrast echocardiography. Although PASP was similar between groups at HA (Sherpas: 30.0 ± 6.0 mmHg; SL-HA: 32.7 ± 4.2 mmHg; P = 0.27), it was greater than SL-SL (19.4 ± 2.1 mmHg; P < 0.001). The proportion of subjects with intracardiac shunt was similar between groups (SL-SL: 41%; Sherpas: 50%). In the remaining subjects, IPAVA blood flow was found in 100% of subjects during acute isocapnic hypoxia at SL, but in only 4 of 7 Sherpas and 1 of 8 SL-HA subjects at rest. In conclusion, differences in resting pulmonary vascular regulation, intracardiac shunt and IPAVA blood flow do not appear to account for any adaptation to HA in Sherpas. Despite elevated pulmonary pressures and profound hypoxaemia, IPAVA blood flow in all subjects at HA was lower than expected compared to acute normobaric hypoxia

Genomic Profiling of Childhood Tumor Patient-Derived Xenograft Models to Enable Rational Clinical Trial Design.

Accelerating cures for children with cancer remains an immediate challenge as a result of extensive oncogenic heterogeneity between and within histologies, distinct molecular mechanisms evolving between diagnosis and relapsed disease, and limited therapeutic options. To systematically prioritize and rationally test novel agents in preclinical murine models, researchers within the Pediatric Preclinical Testing Consortium are continuously developing patient-derived xenografts (PDXs)-many of which are refractory to current standard-of-care treatments-from high-risk childhood cancers. Here, we genomically characterize 261 PDX models from 37 unique pediatric cancers; demonstrate faithful recapitulation of histologies and subtypes; and refine our understanding of relapsed disease. In addition, we use expression signatures to classify tumors for TP53 and NF1 pathway inactivation. We anticipate that these data will serve as a resource for pediatric oncology drug development and will guide rational clinical trial design for children with cancer