94 research outputs found
Going Further with Point Pair Features
Point Pair Features is a widely used method to detect 3D objects in point
clouds, however they are prone to fail in presence of sensor noise and
background clutter. We introduce novel sampling and voting schemes that
significantly reduces the influence of clutter and sensor noise. Our
experiments show that with our improvements, PPFs become competitive against
state-of-the-art methods as it outperforms them on several objects from
challenging benchmarks, at a low computational cost.Comment: Corrected post-print of manuscript accepted to the European
Conference on Computer Vision (ECCV) 2016;
https://link.springer.com/chapter/10.1007/978-3-319-46487-9_5
Jamming Model for the Extremal Optimization Heuristic
Extremal Optimization, a recently introduced meta-heuristic for hard
optimization problems, is analyzed on a simple model of jamming. The model is
motivated first by the problem of finding lowest energy configurations for a
disordered spin system on a fixed-valence graph. The numerical results for the
spin system exhibit the same phenomena found in all earlier studies of extremal
optimization, and our analytical results for the model reproduce many of these
features.Comment: 9 pages, RevTex4, 7 ps-figures included, as to appear in J. Phys. A,
related papers available at http://www.physics.emory.edu/faculty/boettcher
Extremal Optimization for Graph Partitioning
Extremal optimization is a new general-purpose method for approximating
solutions to hard optimization problems. We study the method in detail by way
of the NP-hard graph partitioning problem. We discuss the scaling behavior of
extremal optimization, focusing on the convergence of the average run as a
function of runtime and system size. The method has a single free parameter,
which we determine numerically and justify using a simple argument. Our
numerical results demonstrate that on random graphs, extremal optimization
maintains consistent accuracy for increasing system sizes, with an
approximation error decreasing over runtime roughly as a power law t^(-0.4). On
geometrically structured graphs, the scaling of results from the average run
suggests that these are far from optimal, with large fluctuations between
individual trials. But when only the best runs are considered, results
consistent with theoretical arguments are recovered.Comment: 34 pages, RevTex4, 1 table and 20 ps-figures included, related papers
available at http://www.physics.emory.edu/faculty/boettcher
Tuberous sclerosis with pulmonary lymphangioleiomyomatosis and renal angiomyolipomas. Computed tomographic findings: a case report
The authors describe a case of a 31-year-old female with tuberous sclerosis, a genetic, rare, variably expressed disease. Clinical symptoms were chest pain, and progressive dyspnea. Computed tomography scan of the chest showed bilateral, diffuse, small thin-walled cysts scattered throughout the lungs characteristic for pulmonary lymphangioleiomyomatosis. Computed tomography scan of the abdomen revealed enlarged, heterogeneous kidneys, with low density tumors corresponding to angiomyolipomas. Pulmonary lymphangioleiomyomatosis and bilateral renal angiomyolipomas are some presentations of tuberous sclerosis and the coexistence of both conditions may cause devastating morbidity and mortality
Efectos de la nutrición y el riego en la producción de pimiento en toba volcánica
In this study aimed at increasing sustainability in soilless cultivation, volcanic tuff was used as substrate and the tested plant material was blocky type pepper (cv. 4-Ever F1). Three experimental factors were evaluated: cultivation system (open or closed), nutrient composition (N1, N2, N3, N4) and irrigation frequency (I1, I2, I3, I4). Macro nutrient concentrations of N2, N3 and N4 were 2-, 3- and 4-fold of N1. Concentrations of micronutrients were the same for all treatments. Irrigation was started when indoor solar radiation reached 6, 4, 2 and 1 MJ m–2 in the treatments I1, I2, I3 and I4, respectively. As a sustainable soilless technique, closed system was found to be recommendable by incorporating the treatment N4 + I2 to provide high yield and quality for blocky type pepper production. In the case of an open system, N2 + I4 proved to be the most efficient strategy.El objetivo de este estudio fue aumentar la sostenibilidad en un cultivo sin suelo, utilizando como sustrato toba volcánica y como material vegetal pimiento tipo rectangular (cv. 4-Ever F1). Se evaluaron tres factores experimentales: sistema de cultivo (abierto o cerrado), composición de nutrientes (N1, N2, N3, N4) y frecuencia de riego (I1, I2, I3, I4). Las concentraciones N2, N3, y N4de macro nutrientes fueron 2, 3 y 4 veces las de N1, siendo las concentraciones de micronutrientes las mismas para todos los tratamientos. El riego se inició cuando la radiación solar bajo cubierta alcanzó 6, 4, 2 y 1 MJ m2 en los tratamientos I1, I2, I3 e I4, respectivamente. Como técnica de cultivo sin suelo sostenible, en el sistema cerrado los tratamientos que proporcionan mayor rendimiento y calidad de pimiento son N4 + I2. En el caso de sistema abierto, la estrategia más eficiente es utilizar los tratamientos N2 + I4
Transitional cell carcinoma of the ureter and renal pelvis
Transitional cell carcinoma (TCC) of ureter and renal pelvis is relatively uncommon. Smoking, occupational carcinogens, analgesic abuse, Balkan nephropathy are, the risk factors. Cytogenetic studies revealed that the most frequent aberration is the partial or complete loss of chromosome 9. Approximately 20-50% of patients with upper urinary tract (UUT) TCC have bladder cancer at some point on their course, whereas the incidence of UUT TCC after primary bladder cancer is 0.7-4%. Excretory urography and retrograde pyelography are the conventional diagnostic tools; however, ureteropyeloscopy combined with cytology and biopsy is more accurate. Grade and stage of the disease have the most significant impact on survival. Nephroureterectomy with bladder cuff excision has been the mainstay of treatment. Local resection may be appropriate for distal ureteral lesions especially when the disease is low grade and stage. Advances in endourology have made it possible to treat many tumors conservatively. Ureteroscopic and to a certain extent percutaneous surgical approaches are widely used today especially in patients with low grade, low stage disease. Endoscopic close surveillance is mandatory for these patients. Adjuvant topical therapies appear to be safe but confirmation of any benefits awaits the results of further large studies. More recently, laparoscopic techniques have become a viable alternative to open surgery, but long term cancer control data are lacking. Aggressive surgical resection does not affect the outcome of patients with advanced disease. Adjuvant radiotherapy is ineffective, and systemic chemotherapy results in a low complete response rate for patients with metastases. (C) 2003 Elsevier Ireland Ltd. All rights reserved
Effects of irrigation based on different moisture levels of growing medium on soilless grown greenhouse tomatoes
6th Balkan Symposium on Vegetables and Potatoes -- SEP 29-OCT 02, 2014 -- Zagreb, CROATIAWOS: 000392627800015This research was conducted in order to determine effects of irrigation based on different moisture levels of growing medium on yield, fruit quality and water use efficiency of soilless grown greenhouse tomatoes during fall and spring seasons of 2010 and 2011 in PE covered greenhouse. The treatments were composed of full and two deficit irrigation programs. Irrigations were started automatically according to the soil moisture sensor readings when available moisture capacity of substrate was consumed 20% (full), 40% (deficit 1) or 60% (deficit 2) respectively in the plant root zone. Experiments were set according to the randomized blocks design with four replicates. Drip irrigation method was used in nutrient solution supply and timing was based on soil moisture sensors placed at root zone. The duration of irrigation was set according to the daily leaching fraction which was kept around 30-40%. In both seasons the highest total and marketable yield was obtained from plants under full irrigation. Compared with full irrigation, total yield in autumn decreased 19.2 and 19.3% in deficit 1 and deficit 2, respectively, while it was 35.2 and 32.1% lower in spring. It was determined that plant growth, water use efficiency (WUE) and some fruit quality parameters showed differences in irrigation treatments according to growing seasons. Total soluble solids, titratable acidity, EC of fruit juice, total antioxidants and vitamin C increased with water deficit. The highest WUE was determined in deficit 2 in autumn and full irrigation in spring. It was concluded that water deficit could be applied in autumn, however, more attention should be paid to irrigation since there are more risks in spring season production.Int Soc Hort Sc
Effects of nutrition and irrigation on sweet pepper production in volcanic tuff
In this study aimed at increasing sustainability in soilless cultivation, volcanic tuff was used as substrate and the
tested plant material was blocky type pepper (cv. 4-Ever F1). Three experimental factors were evaluated: cultivation
system (open or closed), nutrient composition (N1, N2, N3, N4) and irrigation frequency (I1, I2, I3, I4). Macro nutrient
concentrations of N2, N3 and N4 were 2-, 3- and 4-fold of N1. Concentrations of micronutrients were the same for all
treatments. Irrigation was started when indoor solar radiation reached 6, 4, 2 and 1 MJ m�2 in the treatments I1, I2, I3
and I4, respectively. As a sustainable soilless technique, closed system was found to be recommendable by incorporating
the treatment N4 + I2 to provide high yield and quality for blocky type pepper production. In the case of an open system,
N2 + I4 proved to be the most efficient strategy.El objetivo de este estudio fue aumentar la sostenibilidad en un cultivo sin suelo, utilizando como sustrato toba volcánica
y como material vegetal pimiento tipo rectangular (cv. 4-Ever F1). Se evaluaron tres factores experimentales:
sistema de cultivo (abierto o cerrado), composición de nutrientes (N1, N2, N3, N4) y frecuencia de riego (I1, I2, I3, I4).
Las concentraciones N2, N3, y N4de macro nutrientes fueron 2, 3 y 4 veces las de N1, siendo las concentraciones de
micronutrientes las mismas para todos los tratamientos. El riego se inició cuando la radiación solar bajo cubierta alcanzó
6, 4, 2 y 1 MJ m2 en los tratamientos I1, I2, I3 e I4, respectivamente. Como técnica de cultivo sin suelo sostenible,
en el sistema cerrado los tratamientos que proporcionan mayor rendimiento y calidad de pimiento son N4 + I2. En
el caso de sistema abierto, la estrategia más eficiente es utilizar los tratamientos N2 + I4
Use of different growing media and nutrition in organic seedling production
29th International Horticultural Congress on Horticulture - Sustaining Lives, Livelihoods and Landscapes (IHC) / International Symposium on Innovation and New Technologies in Protected Cropping -- AUG 17-22, 2014 -- Brisbane, AUSTRALIAWOS: 000378731500022Legislation in organic agriculture also sets up the rules for production of seeds and other plant propagation materials. In Turkey, organic seedlings are raised mostly by the farmers themselves since propagation material released from commercial nurseries is very limited due to the lack of standard protocols and research under controlled organic conditions. The aim of this research was to develop growing medium as an alternative due to the pressures on peat as a non-renewable resource and fertilization programs using local resources that could be applicable at commercial level to produce organic tomato ('Meils') seedlings. In two experiments, liquid vermicompost, diluted poultry manure and liquid composted farmyard manure were tested in order to develop the nutritional program with (1) peat, (2) local peat + clinoptilolite + vermicompost (1:1:1; v:v), (3) local peat + perlite + vermicompost (1:1:1; v:v) and (4) local peat (60%) + vermicompost (40%). In the first experiment, only the effect of growing media on shoot dry weight was found significantly different while in the second one the main and interaction effects of treatments were significant. The mixture of local peat and vermicompost was as good as peat in terms of shoot fresh and dry weights. Among the tested fertilizers, liquid composted farmyard and poultry manure were found promising however liquid composted farmyard manure could be more appropriate for commercial use considering its effects on plant fresh weight, availability and cost.Int Soc Hort Sc
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