81 research outputs found
Timing diagrams requirements modeling using Event-B formal methods
No full textTiming diagrams provide an intuitive graphical specification for time constraints and causal dependencies between a system’s objects. Such a view can provide useful insight during Requirements Engineering (RE). Formal Modeling techniques allow abstract system level models to be explored in revealing detail and provide feedback via verification and validation methods such as proofs of consistency, model checking and animation. Here, we bring these two modelling approaches together. In particular we present techniques to extend a graphical modeling capability for formal modeling into the real-time domain by developing a Timing diagram view for the Event-B formal method and its graphical front-end, UML-B. Translation schemes to Event-B and UML-B are proposed and presented. A case study of a lift system is used to demonstrate the translation in practice
Overlook poem with Mackinac Island poem
No full textPrinted text of two poems written by John. J. Snook: Overlook and Mackinac Island. Handwritten notes by the author correcting text
Rib/snook design in mechanised depillaring of rectangular/square pillars
No full textThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.A field study at different mechanised depillaring (MD) operations in Indian coalfields (with depth ranging from 60 to 377 m and caveability Index variation from 2300 to 10500) found mixed performances of adopted sizes of the ribs/snooks. Formation of an irregular shaped rib/snook during MD of the existing square/rectangular pillars by a continuous miner and uniqueness of the existing geo-mining conditions limit scope of application of the conventional rib/snook design approaches. Taking guidance from the field studies, a parametric investigation is conducted in laboratory on the calibrated simulated models using FLAC3D. An analysis of stress redistribution for different stages of the MD in simulated models provided a different characteristic of an irregular shaped ribs/snooks failure. Presence of moderate roof strata is found to be, relatively, more significant for the rib/snook design. Based on the simulation results, an attempt is made to provide a model for the rib/snook design in MDCSIR-CIMF
Clinical Results and Functional Evaluation of the Chrisman-Snook Procedure for Lateral Ankle Instability in Athletes
No full textThere is no consensus regarding optimum surgical treatment for chronic ankle instability. The purpose of this study is to describe a variation of the Chrisman-Snook lateral ligament reconstruction that the senior author uses in patients with chronic ankle instability recalcitrant to conservative management. All patients who underwent reconstruction from 1997 to 2006 were identified, and those with a minimum 2-year follow-up were included, representing a total of 44 ankles in 43 patients. All underwent clinical evaluation and completion of the Foot and Ankle Outcome Survey and the Kaikkonen Scale. At mean follow-up of 4.4 years, mean dorsiflexion loss was 2° compared with the nonoperative side. The postoperative mean Foot and Ankle Outcome Survey score was 74 ± 16 (range, 36-98), while the mean Kaikkonen total score was 77 ± 14 (range, 40-95). Thirty-eight patients (84.6%) were satisfied with their result. Six patients (13.6%) underwent reoperation, including 4 with peroneal tendon scarring requiring tenolysis. Return to sport was achieved in 28 of 35 patients (80%) at a median of 6 months postoperatively. It is concluded that dorsiflexion loss can be minimized and return to sport expected in most patients following this variation of the Chrisman-Snook reconstruction.Levels of Evidence: Therapeutic, Level IV</jats:p
Linkage analysis in cases of serial burglary : comparing the performance of university students, police professionals, and a logistic regression model
No full textUniversity students, police professionals, and a logistic regression model were provided with information on 38 pairs of burglaries, 20% of which were committed by the same offender, in order to examine their ability to accurately identify linked serial burglaries. For each offense pair, the information included: (1) the offense locations as points on a map, (2) the distance (in km) between the two offenses, (3) entry methods, (4) target characteristics, and (5) property stolen. Half of the participants received training informing them that the likelihood of two offenses being committed by the same offender increases as the distance between the offenses decreases. Results showed that students outperformed police professionals, that training increased decision accuracy, and that the logistic regression model achieved the highest rate of success. Potential explanations for these results are presented, focusing primarily on the participants' use of offense information, and their implications are discussed
Investigation of Colorado front range winter storms using a nonhydrostatic mesoscale numerical model designed for operational use
No full textFall 1993.Also issued as author's sdissertation (Ph.D.) -- Colorado State University, 1993.State-of-the-art data sources such as Doppler radar, automated surface observations, wind profiler, digital satellite, and aircraft reports are for the first time providing the capability to generate real-time, operational three-dimensional gridded data sets with sufficient spatial and temporal resolutions to diagnose the structure and evolution of mesoscale systems. A prototype data assimilation system of this type, called the Local Analysis and Prediction System (LAPS), is being developed at the National Oceanic and Atmospheric System's Forecast Systems Laboratory (FSL). The investigation utilizes the three-dimensional LAPS analyses for initialization of the full physics, nonhydrostatic Regional Atmospheric Modeling System (RAMS) model developed at the Colorado State University to create a system capable of generating operational mesoscale predictions. The LAPS/RAMS system structured for operational use can add significant value to existing operational model output and can provide an improved scientific understanding of mesoscale weather events. The results a.re presented through two case study analyses, the 7 January 1992 Colorado Front Range blizzard and the 8-9 March 1992 eastern Colorado snowstorm. Both cases a.re ideal for this investigation due to the significant mesoscale variation observed in the precipitation and flow structure. The case study results demonstrate the ability to successfully detect and predict mesoscale features using a mesoscale numerical model initialized with high resolution (10 km horizontal grid interval), non homogeneous data. Conceptual models of the two snowstorms are developed by utilizing the RAMS model output in combination with observations and other larger domain model simulations. The strong influence of the Colorado topography on the resultant flow is suggested by the generation of a lee vortex that frequently develops east of the Front Range and south of the Cheyenne Ridge in stable, northwest synoptic flow. The lee vortex, often called the "Longmont anticyclone", exhibits surface flow characteristics that are similar to results from low Froude number flow around an isolated obstacle. A series of numerical experiments using RAMS with idealized topography and horizontally homogeneous initial conditions are presented to investigate typical low Froude number flow characteristics in the vicinity of barriers representative of the Colorado topography. The results are compared to the findings of previous investigations and to the case study observations and numerical predictions. The findings suggest that the Colorado orography significantly altered the low-level flow in both case studies resulting in mesoscale variation of observed precipitation. Improved representation of the topography by the model led to the majority of the forecast improvement
Antiamoebin can function as a carrier or as a pore-forming peptaibol
No full textAbstractAntiamoebin is a 16-residue polypeptide whose crystal structure and lytic activity in membrane vesicles have recently been reported. It is a bent helical molecule and a member of the peptaibol family of antibiotics. Under conditions which produce voltage-dependent conductance activity by other members of the family, no single-channel conductance was detected for antiamoebin, and a carrier-like mechanism was put forward to account for its mode of action. We now present evidence for pore formation that is largely voltage-insensitive, with large amplitude single-channel events on top of a background conductance that may account for the previously proposed carrier-like activity. Thus, antiamoebin may be the first instance of a peptide which can function both as an ion carrier and a pore former
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