PotLLL: A Polynomial Time Version of LLL With Deep Insertions

Lattice reduction algorithms have numerous applications in number theory, algebra, as well as in cryptanalysis. The most famous algorithm for lattice reduction is the LLL algorithm. In polynomial time it computes a reduced basis with provable output quality. One early improvement of the LLL algorithm was LLL with deep insertions (DeepLLL). The output of this version of LLL has higher quality in practice but the running time seems to explode. Weaker variants of DeepLLL, where the insertions are restricted to blocks, behave nicely in practice concerning the running time. However no proof of polynomial running time is known. In this paper PotLLL, a new variant of DeepLLL with provably polynomial running time, is presented. We compare the practical behavior of the new algorithm to classical LLL, BKZ as well as blockwise variants of DeepLLL regarding both the output quality and running time.Comment: 17 pages, 8 figures; extended version of arXiv:1212.5100 [cs.CR

Micro-Doppler Based Human-Robot Classification Using Ensemble and Deep Learning Approaches

Radar sensors can be used for analyzing the induced frequency shifts due to micro-motions in both range and velocity dimensions identified as micro-Doppler ($\boldsymbol{\mu}$-D) and micro-Range ($\boldsymbol{\mu}$-R), respectively. Different moving targets will have unique $\boldsymbol{\mu}$-D and $\boldsymbol{\mu}$-R signatures that can be used for target classification. Such classification can be used in numerous fields, such as gait recognition, safety and surveillance. In this paper, a 25 GHz FMCW Single-Input Single-Output (SISO) radar is used in industrial safety for real-time human-robot identification. Due to the real-time constraint, joint Range-Doppler (R-D) maps are directly analyzed for our classification problem. Furthermore, a comparison between the conventional classical learning approaches with handcrafted extracted features, ensemble classifiers and deep learning approaches is presented. For ensemble classifiers, restructured range and velocity profiles are passed directly to ensemble trees, such as gradient boosting and random forest without feature extraction. Finally, a Deep Convolutional Neural Network (DCNN) is used and raw R-D images are directly fed into the constructed network. DCNN shows a superior performance of 99\% accuracy in identifying humans from robots on a single R-D map.Comment: 6 pages, accepted in IEEE Radar Conference 201

Stairs Detection for Enhancing Wheelchair Capabilities Based on Radar Sensors

Powered wheelchair users encounter barriers to their mobility everyday. Entering a building with non barrier-free areas can massively impact the user mobility related activities. There are a few commercial devices and some experimental that can climb stairs using for instance adaptive wheels with joints or caterpillar drive. These systems rely on the use for sensing and control. For safe automated obstacle crossing, a robust and environment invariant detection of the surrounding is necessary. Radar may prove to be a suitable sensor for its capability to handle harsh outdoor environmental conditions. In this paper, we introduce a mirror based two dimensional Frequency-Modulated Continuous-Wave (FMCW) radar scanner for stair detection. A radar image based stair dimensioning approach is presented and tested under laboratory and realistic conditions.Comment: 5 pages, Accepted and presented in 2017 IEEE 6th Global Conference on Consumer Electronics (GCCE 2017

Honesty and Self-Selection into Cheap Talk

In many situations, people can lie strategically for their own benefit. Since individuals differ with respect to their willingness to lie, the credibility of statements will crucially depend on who self-selects into such cheap-talk situations. We study this process in a two-stage political competition setting. At the entry stage, potential candidates compete in a contest to become their party’s candidate in an election. At the election stage, the nominated candidates campaign by making promises to voters. Confirming the model’s key prediction, we find in our experiment that dishonest people over-proportionally self-select into the political race and thereby lower voters’ welfare.publishe

Sudden death after open gastric bypass surgery

Purpose: Gastric bypass surgery has become a relatively low-risk bariatric surgical intervention in a high-risk patient population (Nguyen et al., Arch Surg, 141:445-449, 2006; Buchwald et al. JAMA, 13:1724-1737, 2004). Surgical interventions in patients suffering from morbid obesity are typically associated with excess morbidity (Parikh et al., Am Surg, 73:959-962, 2007). Though overall mortality after bariatric surgery is <1% is low (Mason et al., Obes Surg, 17:9-14, 2007), some surgical complications such as anastomotic leaks, staple line disruption and bowel obstruction may still impact on postoperative outcome (Parikh et al., Am Surg, 73:959-962, 2007; Mason et al., Obes Surg, 17:9-14, 2007). Early symptoms are often missed, as clinical presentation may be discreet, inexistent or falsely attributed to obesity. Methods: This case report refers to a patient in whom discomfort and agitation associated with a rise in temperature heralded a fulminant septic shock syndrome precipitating his death. Literature on early complications and management after gastric bypass is reviewed. Conclusion: A high level of suspicion should be present in the case of an unexpected postoperative deterioration of the patient's general condition. Time to treat may be very short (Mason et al., Obes Surg, 17:9-14, 2007). Computed tomography is mandatory to rule out pulmonary embolism and bypass obstructio

Long-term performance of organic crop rotations in the tropics: First results from a high and a medium potential site in sub-humid Central Kenya

Organic Agriculture is perceived by many stakeholders as a promising approach to increase food security in developing countries. However, only few attempts have been made so far to assess agronomic and economic performance of Organic Agriculture in these regions in a systematic way. The Research Institute of Organic Agriculture (FiBL), together with its partners, is presently establishing long-term comparisons of farming systems in various agro-ecological and socio-economic contexts to study the different parameters that are essential for sustainable development. To date, three study areas have been selected: (a) a sub-humid area in Kenya where farming is subsistence-oriented; (b) a semi-arid area in India where cotton is produced for the export market; and (c) a humid area in Bolivia where cacao and other perennial products are produced for the export and domestic markets. The key elements are replicated long-term field trials. These are complemented by farm surveys and short-term trials under on-farm conditions. This network of comparison of farming systems in the tropics is expected to (1) put the discussion on the benefits and drawbacks of Organic Agriculture on a rational basis; (2) help to identify challenges for Organic Agriculture that can then be addressed systematically; (3) provide physical reference points for stakeholders in agricultural research and development and thus support agricultural policy dialogue at different levels. In Kenya, the two trials sites are located in a high potential zone in Meru South District (Chuka) and in a medium potential zone in Maragua District (Thika). They consist of four treatments: conventional and organic, each at a low and a high input level, representing subsistence oriented and commercial farming, respectively. Maize, brassicas and maize were planted during the first, second and third season respectively in both organic and conventional plots. In the first three seasons, we found the following results: in Chuka, organic yields of the low input treatments were on average 4% lower than conventional yields. On the high input level, organic yields were 6% lower. In Thika, organic yields were on average 57% (low input level) and 33% (high input level) lower than conventional yields. It is assumed that the organic crops in Chuka could benefit from N and P mobilisation from the soil. In Thika, where N and P were probably less available, the crop depended on the easily soluble nutrients applied in the conventional treatments. The effect of lower nutrient availability in the organic treatments in Thika was possibly aggravated by serious drought spells during the second and third season. The questions of interest are a) whether the organic treatments can keep the yield level of the conventional treatments in Chuka or if they will go through a depression typical for conversion from conventional to Organic Agriculture; and b) if the organic treatments can improve soil fertility and thus the organic yield levels in Thika in the coming years

Mental disorders in the Pediatric Setting- Results of a Swiss Survey

Theoretical background: Mental disorders emerge in childhood and adolescence and are important risk factors for mental disorders in adolescents and adulthood. Since pediatricians typically are the first to see children with psychological problems, the aim of this study was to obtain a survey of mental disorders of children in pediatric settings. Methods: 250 pediatricians completed a questionnaire especially developed for this study, which asked for the estimated frequency and type of mental disorders in their patients, assurance in identifying mental disorders, used diagnostic and treatment strategies for these disorders and requests for training.Results: Pediatricians estimated that 15% percent of children in their pediatric setting reported psychological difficulties. The most frequent mental disorders indicated by the pediatricians were attention-deficit hyperactivity disorder (ADHD), anxiety disorders, depression, and aggressive disorders. Comfort in assigning diagnoses for anxiety disorders and depression was lower than for externalizing disorders. Counseling was the treatment approach most often reported in treating mental disorders, followed by psychopharmacological medication, psychotherapy however being reported very rarely. Their wish for continuing education included diagnostics and screening instruments for psychological problems in childhood. Conclusions: Estimated prevalence rates reported by pediatricians are comparable with rates in epidemiological studies. Because pediatricians are often confronted with psychological problems, they have the important role in recognizing early signs of mental problems

Prophylaxis of Heterotopic Ossification in Patients Sedated after Polytrauma: Medical and Ethical Considerations

Background and Purpose:: Heterotopic ossification (HO) often follows acetabular fractures after multitrauma. Irradiation is a mean for prophylaxis. We established a standard procedure in our hospital for patients under sedation, when obtaining informed consent for HO prophylaxis is impossible. Patients and Methods:: We reviewed current scientific evidence, calculated the risks of radiation and presented the ethical and legal framework. The subject was scrutinised by an interdisciplinary panel. Results:: Irradiation is the most effective means for prophylaxis and has few adverse effects in adult patients with fractures of the acetabulum. The lifetime risk of radiation-induced cancer or infertility are insignificant. Conclusions:: Informed consent for irradiation should be obtained before operation whenever possible. When this cannot be done prophylaxis can be postponed for a maximum of 3 days in order to obtain consent. If the patient is not able to communicate within this period, prophylactic irradiation should be given after consulting the relatives. The patient must be informed as soon as possibl