Regularizing soft decision trees

Recently, we have proposed a new decision tree family called soft decision trees where a node chooses both its left and right children with different probabilities as given by a gating function, different from a hard decision node which chooses one of the two. In this paper, we extend the original algorithm by introducing local dimension reduction via L-1 and L-2 regularization for feature selection and smoother fitting. We compare our novel approach with the standard decision tree algorithms over 27 classification data sets. We see that both regularized versions have similar generalization ability with less complexity in terms of number of nodes, where L-2 seems to work slightly better than L-1.Publisher's VersionAuthor Post Prin

Role of stocking density of tilapia (Oreochromis aureus) on fish growth, water quality and tomato (Solanum lycopersicum) plant biomass in the aquaponic system

The present study reports the results of the production of Nile tilapia (Oreochromis aureus) and tomato (Solanum lycopersicum) in the classical aquaponic system (one-loop) with different fish density. The experiment as the first scientific aquaponics study in Turkey was conducted at the Ankara University, Faculty of Agriculture, using in-door, small-scale classical aquaponic systems. Ninety six tilapia juveniles (O. aureus) were stocked at different ratio; 25 kg/m3 (Group I), 35 kg/m3 (Group II) and 50 kg/m3 (Group III) and fed with 45% raw protein feed at the level of 2% body weight for 126 days. Fish density affected the fish growth parameters and the most densiest group showed the best results in terms of fish growth and feed efficiency. Water quality parameters measured fluctated during the experiment even the exceed of the optimal ranges for the fish. However, tilapia tolerated the changes of water quality. Total plant biomass was low with the various limiting factors including insufficient lighting of in-door aquaponics system and low level of water potassium. The results of this study clearly illustrate the fish stocking rate has an impact on total biomass in the aquaponics and in one-loop aquaponics the water quality fluctation is the main challenging factor

Adsorption of Nitrogen Dioxide (NO2) for Different Gas Concentrations, Temperatures and Relative Humidities by using Activated Carbon Filter: An Experimental Study

Noxious gases can be reduced through activated carbon; nevertheless, this process is very complex due to the changing parameters. Nitrogen dioxides take place in the so-called reactive gases. The nitrogen dioxide concentration existing in the environment can be harmful, in particular for asthmatics and it also has the potential to bring about other serious diseases. For instance, interior diseases are often caused by nitrogen oxide gases. Through this study, we have observed the nitrogen dioxide adsorption on the active carbon for varying air temperatures, gas concentrations and air relative humidities. In this context, it has been examined the effect of all three parameters. While conducting this project, we have used parameters between 1ppm and 30ppm (for NO2 concentration), 23°C and 33°C (for air temperature), 30% and 90% (for air relative humidity). In order to understand this process, breakthrough curves of NO2evaluated from experiments have been used in the present study. Results show that the humidity has not a remarkable effect on the adsorption of NO2; however, increasing relative humidity causes to a decrease in the capacity of the activated carbon for NO2 adsorption. Additionally, NO2 adsorption is exothermic, therefore it increases the air temperature

CAST: Recent results & future outlook

Çetin, Serkant Ali (Dogus Author) -- Ezer, Cemile (Dogus Author) -- Yıldız, Süleyman Cenk (Dogus Author) -- Conference full title: 6th Patras Workshop on Axions, WIMPs and WISPs, PATRAS 2010; Zurich; Switzerland; 5 July 2010 through 9 July 2010.The CAST (CERN Axion Solar Telescope) experiment is searching for solar axions by their conversion into photons inside the magnet pipes of an LHC dipole. The analysis of data taken so far has shown no signal above the background, thus implying an upper limit to the axion-photon coupling of ga < 0.85 × 10-10GeV -1 at 95% CL for ma < 0.02 eV/c2. Ongoing measurements, with the magnet bores filled with a buffer gas (3He), are improving the sensitivity of the experiment for higher axion masses towards 1 eV/c2. Recent results, new ideas for Axion-Like Particle (WISPs) searches with CAST in the near future and the prospects of a new generation Helioscope are presented here

Bringing Order to Special Cases of Klee's Measure Problem

Klee's Measure Problem (KMP) asks for the volume of the union of n axis-aligned boxes in d-space. Omitting logarithmic factors, the best algorithm has runtime O*(n^{d/2}) [Overmars,Yap'91]. There are faster algorithms known for several special cases: Cube-KMP (where all boxes are cubes), Unitcube-KMP (where all boxes are cubes of equal side length), Hypervolume (where all boxes share a vertex), and k-Grounded (where the projection onto the first k dimensions is a Hypervolume instance). In this paper we bring some order to these special cases by providing reductions among them. In addition to the trivial inclusions, we establish Hypervolume as the easiest of these special cases, and show that the runtimes of Unitcube-KMP and Cube-KMP are polynomially related. More importantly, we show that any algorithm for one of the special cases with runtime T(n,d) implies an algorithm for the general case with runtime T(n,2d), yielding the first non-trivial relation between KMP and its special cases. This allows to transfer W[1]-hardness of KMP to all special cases, proving that no n^{o(d)} algorithm exists for any of the special cases under reasonable complexity theoretic assumptions. Furthermore, assuming that there is no improved algorithm for the general case of KMP (no algorithm with runtime O(n^{d/2 - eps})) this reduction shows that there is no algorithm with runtime O(n^{floor(d/2)/2 - eps}) for any of the special cases. Under the same assumption we show a tight lower bound for a recent algorithm for 2-Grounded [Yildiz,Suri'12].Comment: 17 page

Examining the roles of child temperament and teacher-child relationships as predictors of Turkish children’s social competence and antisocial behavior

The present study examined the concurrent contribution of Turkish children’s temperament and teacher-child relationship quality to their social competence and antisocial behavior, with a specific focus on the moderating role of teacher-child relationships (closeness and conflict) on children’s temperament (inhibitory control and shyness) when predicting social competence and antisocial behavior. Participants were 94 children (56 boys) with mean age of 7.05 years (SD = .88) enrolled in 24 classrooms from five elementary schools in a suburban school district in Turkey. Mothers reported on children’s temperament and teachers reported on their relationships with children as well as children’s social competence and antisocial behavior. SAS PROC MIXED was used to test hierarchical regression models of children nested within classrooms. Results showed that high conflict teacher-child relationships moderated the association between low shyness and antisocial behavior. Less shy children displayed more antisocial behavior at higher levels of teacher-child conflict. In addition, at high levels of child shyness, social competence ratings improved as teacher-child closeness increased. Inhibitory control was positively correlated with social competence and negatively correlated with antisocial behavior. The qualities of teacher-child relationships can effectively support children’s social competence and antisocial behavior depending upon their temperamental characteristics. Limitations and future directions of the current study are discussed

Mitigating Tipburn True Foliar Calcium Application in Indoor Hydroponicly Grown Mini Cos Lettuce

Hydroponic systems provide a highly advantageous environment for cultivating green leafy vegetables. Among these advantages, there is a significant acceleration in harvest compared to conventional farming methods, the attainment of high yields, enhanced leaf coloring, increased nutritional content, and improved sweetness, all of which are crucial factors. However, a particular issue known as tip burn is encountered when cultivating, especially Yedikule (Romaine) type lettuce in hydroponic systems. This study investigates various calcium dosages applied via foliar spray to mitigate tip burn on Thespian and Suntred lettuce varieties (green and red Romaine mini types). Different calcium dosages were employed for both lettuce varieties. This experiment examined various parameters for both lettuce types, including plant height, root length, stem diameter, plant age, dry weight, root dry and fresh weight, macro and micronutrient content, dry matter, and total yield. The results indicate that combining foliar calcium and adequate ventilation effectively mitigates tipburn. This research emphasizes the significance of such a combined approach in preventing tip burn in hydroponically grown lettuce, specifically Thespian and Suntred varieties

Spectra disentangling applied to the Hyades binary Theta^2 Tau AB: new orbit, orbital parallax and component properties

Theta^2 Tauri is a detached and single-lined interferometric-spectroscopic binary as well as the most massive binary system of the Hyades cluster. The system revolves in an eccentric orbit with a periodicity of 140.7 days. The secondary has a similar temperature but is less evolved and fainter than the primary. It is also rotating more rapidly. Since the composite spectra are heavily blended, the direct extraction of radial velocities over the orbit of component B was hitherto unsuccessful. Using high-resolution spectroscopic data recently obtained with the Elodie (OHP, France) and Hermes (ORM, La Palma, Spain) spectrographs, and applying a spectra disentangling algorithm to three independent data sets including spectra from the Oak Ridge Observatory (USA), we derived an improved spectroscopic orbit and refined the solution by performing a combined astrometric-spectroscopic analysis based on the new spectroscopy and the long-baseline data from the Mark III optical interferometer. As a result, the velocity amplitude of the fainter component is obtained in a direct and objective way. Major progress based on this new determination includes an improved computation of the orbital parallax. Our mass ratio is in good agreement with the older estimates of Peterson et al. (1991, 1993), but the mass of the primary is 15-25% higher than the more recent estimates by Torres et al. (1997) and Armstrong et al. (2006). Due to the strategic position of the components in the turnoff region of the cluster, these new determinations imply stricter constraints for the age and the metallicity of the Hyades cluster. The location of component B can be explained by current evolutionary models, but the location of the more evolved component A is not trivially explained and requires a detailed abundance analysis of its disentangled spectrum.Comment: in press, 13 pages, 10 Postscript figures, 5 tables. Table~4 is available as online material. Keywords: astrometry - techniques: high angular resolution - stars: binaries: visual - stars: binaries: spectroscopic - stars: fundamental parameter

Uncertainties in models of stellar structure and evolution

Numerous physical aspects of stellar physics have been presented in Ses- sion 2 and the underlying uncertainties have been tentatively assessed. We try here to highlight some specific points raised after the talks and during the general discus- sion at the end of the session and eventually at the end of the workshop. A table of model uncertainties is then drawn with the help of the participants in order to give the state of the art in stellar modeling uncertainties as of July 2013.Comment: Proc. of the workshop "Asteroseismology of stellar populations in the Milky Way" (Sesto, 22-26 July 2013), Astrophysics and Space Science Proceedings, (eds. A. Miglio, L. Girardi, P. Eggenberger, J. Montalban