Component-wise incremental LTL model checking

Efficient symbolic and explicit-state model checking approaches have been developed for the verification of linear time temporal logic (LTL) properties. Several attempts have been made to combine the advantages of the various algorithms. Model checking LTL properties usually poses two challenges: one must compute the synchronous product of the state space and the automaton model of the desired property, then look for counterexamples that is reduced to finding strongly connected components (SCCs) in the state space of the product. In case of concurrent systems, where the phenomenon of state space explosion often prevents the successful verification, the so-called saturation algorithm has proved its efficiency in state space exploration. This paper proposes a new approach that leverages the saturation algorithm both as an iteration strategy constructing the product directly, as well as in a new fixed-point computation algorithm to find strongly connected components on-the-fly by incrementally processing the components of the model. Complementing the search for SCCs, explicit techniques and component-wise abstractions are used to prove the absence of counterexamples. The resulting on-the-fly, incremental LTL model checking algorithm proved to scale well with the size of models, as the evaluation on models of the Model Checking Contest suggests.     

High throughput processing of the structural information in the protein data bank

The protein data bank (PDB) is the largest, most comprehensive, freely available depository of protein structural information, containing more than 37 500 deposited structures. On one hand, the form and the organization of the PDB seems to be perfectly adequate for gathering information from specific protein structures, by using the bibliographic references and the informative remark fields. On the other hand, however, it seems to be impossible to automatically review remark fields and journal references for processing hundreds or thousands of PDB files.

We present here a family of combinatorial algorithms to solve some of these problems. Our algorithms are capable to automatically analyze PDB structural information, identify missing atoms, repair chain ID information, and most importantly, the algorithms are capable of identifying ligands with their respective binding sites.     

Electron‐beam curing of bismaleimide‐reactive diluent resins

Electron‐beam (E‐beam) curing of 4,4′‐bismaleimidodiphenylmethane (BMPM)/BMI‐1,3‐tolyl/o,o′‐diallylbisphenol A (DABPA)–based bismaleimide (BMI) systems and their mixing with various reactive diluents, such as N‐vinylpyrrolidone (NVP) and styrene, were investigated to elucidate how temperature, electron‐beam dosage, and diluent concentration affect the cure extent. The effect of free‐radical initiator on the cure reactions was also studied. It was found that low‐intensity E‐beam exposures cannot cause the polymerization of BMI. High‐intensity E‐beam exposures give high reaction conversion attributed to a high temperature increase, which induced thermal curing. It was shown that the dilution and activation of NVP in BMI cause a more complete BMI cure reaction under E‐beam radiation. BMI/NVP can be initiated easily by low‐intensity E‐beam without thermal curing. FTIR studies indicate that about 70% of the reaction is complete for BMI/NVP with 200 kGy dosage exposure at 10 kGy per pass. The sample temperature only reaches about 75°C. The free‐radical initiator, dicumyl peroxide, can accelerate the reaction rate at the beginning of E‐beam exposure, but does not affect the final reaction conversion. The increase of the concentration of NVP in the BMI/NVP systems increases the reactive conversions almost linearly. © 2004 Wiley Periodicals Inc. J Appl Polym Sci 94: 2407‐2416, 2004     

Improved mathematical modeling for the sheet reheat phase during thermoforming

In any thermoforming process, plastic sheet heating is the most important phase as it is responsible for final part quality as well as overall process efficiency and productivity. The goal of the study reported here was to improve existing mathematical models to accurately predict the temperature profile inside a heated sheet, where the model could be used to better control the overall thermoforming process. A mathematical model with temperature dependent, variable sheet material properties including density, thermal diffusivity, specific heat, and thermal conductivity was developed and validated against experimental data. Models with constant and variable plastic sheet properties were created, simulated, and compared in Matlab. The models were validated by experiments which obtained temperature profiles at different depths within a plastic sheet by inserting thermocouples and recording temperatures. Further, the effect of sheet color on heating was investigated by considering two extreme cases: white (transparent) and black (opaque) colored sheets, and the effect of oven air temperature and velocity on sheet heating was also investigated. Results indicated that a variable properties model was needed to control sheet reheating especially with narrow forming windows, and that the heating profiles required for colored and noncolored sheets were very different. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers     

Aspartame in conjunction with carbohydrate reduces insulin levels during endurance exercise

Background

As most sport drinks contain some form of non-nutritive sweetener (e.g. aspartame), and with the variation in blood glucose regulation and insulin secretion reportedly associated with aspartame, a further understanding of the effects on insulin and blood glucose regulation during exercise is warranted. Therefore, the aim of this preliminary study was to profile the insulin and blood glucose responses in healthy individuals after aspartame and carbohydrate ingestion during rest and exercise.

Findings

Each participant completed four trials under the same conditions (45?min rest?+?60?min self-paced intense exercise) differing only in their fluid intake: 1) carbohydrate (2% maltodextrin and 5% sucrose (C)); 2) 0.04% aspartame with 2% maltodextrin and 5% sucrose (CA)); 3) water (W); and 4) aspartame (0.04% aspartame with 2% maltodextrin (A)). Insulin levels dropped significantly for CA versus C alone (43%) between pre-exercise and 30?min, while W and A insulin levels did not differ between these time points.

Conclusions

Aspartame with carbohydrate significantly lowered insulin levels during exercise versus carbohydrate alone.     

大屏幕LED背光液晶显示器批量生产的问题

对环境的保护,包括减少有害物质的使用、减少能源消耗以及延长产品使用寿命的需求,正在成为非冷阴极（non—CCFL—based）背光技术发展的动力。虽然批量生产的问题现在正在发生变化,但成本和技术上的壁垒曾经使得基于LED方案的产量难以提高。     

Agronomic Performance and Seed Inorganic Phosphorus Stability of Low‐Phytate Soybean Line TN09‐239

Phytate (myoinositol‐1,2,3,4,5,6‐hexa‐kisphosphate) in soybean (Glycine max (L.) Merr.) cannot be absorbed by livestock with monogastric digestive systems, and is often excreted in their waste. This can result in agricultural runoff pollution, as well as nutritional deficiencies in poultry (Gallus Gallus domesticus) and swine (Sus domesticus). The enzyme phytase is often applied to break the phytin‐salt bonds and allow for phosphorus (P) absorption, but is an added cost for animal producers. Therefore, we developed a low‐phytate BC₄ ‐ derived line TN09‐239 for comparison of agronomic and seed‐quality traits with the high‐yielding recurrent parent, 5601T. In a replicated, multienvironment field test in Tennessee, TN09‐239 was significantly higher for inorganic P (Pi) (P < 0.001), which is inversely correlated with the seed‐phytate concentration, but significantly lower for yield (P < 0.05) in comparison with the recurrent parent. These findings for increased Pi, but reduced yield, for TN09‐239 in comparison with 5601T were confirmed in the 2010 United States Department of Agriculture (USDA) Uniform Preliminary V Soybean Test grown in 10 southern US environments. 5601T and TN09‐239 differed in Pi stability across southern environments, with linear regression showing 5601T having stability across environments, while TN09‐239 showed variations based on the environments. However, in each environment TN09‐239 displayed nearly a 10‐fold increase in Pi compared to 5601T. Although the low‐phytate trait and much of the recurrent parent genome along with 85–90% of the yield have been captured, further backcrossing could help recover the remaining seed yield of 5601T and other traits desirable for southern US producers.     

A Technical Review of SCA Based Software Defined Radios: Vision,Reality and Current Status

The SCA 2.2.2 architecture has achieved widespread adoption in the military communications market. Hundreds of thousands of SCA enabled software defined radios (SDRs) have been deployed to date, and world-wide dozens of programs are working to field more of these types of radios. The reasons for this success are the benefits enabled through adoption of the SCA: proven cost and delivery time advantages, lower logistical overhead through enhanced inter-component interoperability, simplified insertion of new communications capabilities in deployed radios, enhanced coalition interoperability through portability of waveforms and reduced development risk. As a result of this success, new countries and new organizations have begun to explore the use of the SCA, driving a second generation of SDR market adoption. Successful deployment of SCA 2.2.2 based SDRs has identified improvements to be made to advance the technology further. The Wireless Innovation Forum is working in close collaboration with the U.S. Department of Defense Joint Tactical Networking Center (JTNC) to evolve the SCA. The resulting SCA 4.1 specification represents the future of defense SDR technology.     

Life Guard: Evaluation of an ACT-based workshop to facilitate reintegration of OIF/OEF veterans.

Over 2 million soldiers have been deployed to Iraq and Afghanistan since 2001. Evidence suggests that they confront significant difficulties postdeployment, including psychosocial problems such as depression, PTSD, substance abuse, and family distress. Few programs to promote healthy reintegration exist that are evidence-based and designed for those not in formal mental health care. In response to this need, a 2-hour workshop, Life Guard, was developed for the Arkansas National Guard. The workshop is based upon Acceptance and Commitment Therapy (ACT; Hayes & Strosahl, 2004) and emphasizes skill development to promote resiliency and successful postdeployment reintegration. The purposes of this pilot study were to describe the deployment experiences of OIF/OEF veterans and evaluate the effectiveness of the workshop. The sample included 144 veterans (63 intervention and 81 control) in a quasi-experimental, pre-post design (interim 2 months) with a delayed intervention control group. Both groups were largely young, male, Caucasian, and married. Control participants were significantly older, and more educated. Symptoms of a variety of psychological disorders and social adjustment were assessed at baseline and follow-up. Participants reported high levels of exposure to traumatic events, physical injury, and symptoms of psychosocial distress. In contrast to control participants, intervention participants reported significant declines in symptoms of depression, anxiety, and PTSD, and increases in relationship satisfaction. Only effects for depression and relationship satisfaction remained significant in between-group comparisons. Further work is needed to evaluate Life Guard, but results suggest it is a promising workshop to assist with reintegration and resiliency. (PsycINFO Database Record (c) 2011 APA, all rights reserved)