Search results for "SELE"

showing 10 items of 4721 documents

Metal-Free and User-Friendly Regioselective Hydroxyfluorination of Olefins

2018

A simple, user-friendly, metal-free protocol for the regioselective anti-Markovnikov hydrofluorination of olefins using readily available and inexpensive reagents has been developed. This new approach displays a broader scope than previously reported methodologies and has been applied to the late-stage fluorination of a complex molecule, giving rise to a fluorosteroid derivative. The stereochemistry of the process has also been studied in some detail.

User FriendlyHalogenationMolecular Structure010405 organic chemistryOrganic ChemistryRegioselectivityAlkenes010402 general chemistry01 natural sciencesBiochemistryCombinatorial chemistryArticle0104 chemical scienceschemistry.chemical_compoundchemistryMetal freeMetalsPhysical and Theoretical ChemistryDerivative (chemistry)
researchProduct

Prediction of user action in moving-target selection tasks

2015

Selection of moving targets is a common, yet complex task in human–computer interaction (HCI), and more specifically in virtual reality (VR). Action prediction has proven to be the most comprehensive enhancement to address moving-target selection challenges. Current predictive techniques, however, heavily rely on continuous tracking of user actions, without considering the possibility that target-reaching actions may have a dominant pre-programmed component—this theory is known as the pre-programmed control theory.Thus, based on the pre-programmed control theory, this research explores the possibility of predicting moving-target selection prior to action execution. Specifically, three level…

User intentionPerformanceDifficulté prospectiveMoving-Target selectionIntentionSélection de cibles en mouvementHuman-Computer interactionLoi de FittsProspective difficultyFitts' LawInteraction homme-Machine[SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
researchProduct

Platform for efficient and secure data collection and exploitation in intelligent vehicular networks

2016

Nowadays, automotive area is witnessing a tremendous evolution due to the increasing growth in communication technologies, environmental sensing & perception aptitudes, and storage & processing capacities that we can find in recent vehicles. Indeed, a car is being a kind of intelligent mobile agent able to perceive its environment, sense and process data using on-board systems and interact with other vehicles or existing infrastructure. These advancements stimulate the development of several kinds of applications to enhance driving safety and efficiency and make traveling more comfortable. However, developing such advanced applications relies heavily on the quality of the data and therefore…

VANETAnalyse de donnéesData analysisSécuritéNetwork SelectionQuality of serviceCollecte de donnéesData collectionSecurity[INFO.INFO-DB] Computer Science [cs]/Databases [cs.DB]Qualité de ServiceRoutageRoutingSelection du réseau
researchProduct

Fuzzy Investment Portfolio Selection Models Based on Interval Analysis Approach

2012

Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/628295 This paper employs fuzzy set theory to solve the unintuitive problem of the Markowitz mean-variance (MV) portfolio model and extend it to a fuzzy investment portfolio selection model. Our model establishes intervals for expected returns and risk preference, which can take into account investors' different investment appetite and thus can find the optimal resolution for each interval. In the empirical part, we test this model in Chinese stocks investment and find that this model can fulfill different kinds of investors' objectives. Fi…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Actuarial scienceArticle SubjectComputer scienceInvestment strategyApplication portfolio managementGeneral Mathematicslcsh:MathematicsGeneral EngineeringBlack–Litterman modellcsh:QA1-939VDP::Social science: 200::Economics: 210::Econometrics: 214lcsh:TA1-2040Return on investmentEconometricsPost-modern portfolio theoryPortfolio optimizationlcsh:Engineering (General). Civil engineering (General)Investment performanceSelection (genetic algorithm)Mathematical Problems in Engineering
researchProduct

Latvijas alus iespēju analīze eksportam uz Latīņameriku

2022

Maģistra darba tēma ir “Analīze par Latvijas alus eksporta iespējām Latīņamerikā”. Darba autore ir Jarlotte Camila Quintero Martinez un darba vadītājs - Prof., Erika Sumilo. Maģistra darba mērķis ir noteikt, kurš modelis tiks izmantots starptautiskā tirgus atlasei, un veikt Latīņamerikas tirgus izpēti, lai noskaidrotu, kura šī reģiona valsts būtu piemērotākā Latvijas alus eksportam. Lai sasniegtu maģistra darba mērķi, tiek veikta Latīņamerikas valstu izpēte, īstenota teorētiskā materiāla analīze par starptautisko tirgus atlases modeļu raksturojumu, kā arī riska pārvaldības un eksporta barjerām, tā rezultātā nosakot valsti ar labāko vidi Latvijas alus eksportam. Maģistra darbs sastāv no piec…

VadībzinātneDecision Support ModelRisk ManagementInternational Market Selection ModelsExportBeer industry
researchProduct

The Multi-Faceted Concept of Transparency

2014

Transparency has become a catchword and in the economic-political debate is often seen as a universal remedy for all sorts of problems. In this paper, we analyze and discuss the meaning and use of the concept of transparency in economic research. We look for common denominators across different areas where the concept is used, and find that transparency in essence is about reductions in information asymmetries, and therefore entails the transfer of information from a sender to a receiver. Transparency goes beyond mere information disclosure in that it has a demand-side dimension: the information transferred should be trustworthy and have a value to the receiver. We emphasize the distinction…

Value (ethics)MicroeconomicsInformation asymmetryEx-anteMoral hazardAccountabilityAdverse selectionBusinessCommunication sourceTransparency (behavior)SSRN Electronic Journal
researchProduct

A SELECTION OF METHODS AND TECHNIQUES PROFESSIONAL TEACHERS CAN APPLY TO THEIR OWN LIFELONG LEARNING

2018

A selection of methods and techniques professional teachers can apply to their own lifelong learning.Education is the key to converting knowledge and experience into practical actions, their analysis and application. It plays a key role in the synthesis of new knowledge into research and innovation. Such thoughts on education were expressed in the resolution of the sixth World Education Congress in 2011. Today, when world education forums are widely discussing how schools can better organise the learning process, when ambitious long-term reforms are being implemented in the Latvian education system—the transition to competency-based educational content and teaching methods—it is essential t…

Value (ethics)Process (engineering)business.industryLifelong learningProfessional developmentContext (language use)emotional and intellectual activity; pedagogical patterns; professional growth; teacher trainingPersonal developmentActive learningSelection (linguistics)Mathematics educationComputingMilieux_COMPUTERSANDEDUCATIONPsychologybusinessSOCIETY. INTEGRATION. EDUCATION. Proceedings of the International Scientific Conference
researchProduct

Review Paper: Are reproductive skew models evolutionarily stable?

2003

Reproductive skew theory has become a popular way to phrase problems and test hypotheses of social evolution. The diversity of reproductive skew models probably stems from the ease of generating new variations. However, I show that the logical basis of skew models, that is, the way in which group formation is modelled, makes use of hidden assumptions that may be problematical as they are unlikely to be fulfilled in all social systems. I illustrate these problems by re-analysing the basic concessive skew model with staying incentives. First, the model assumes that dispersal is an all-or-nothing response: all subordinates disperse as soon as concessions drop below a certain value. This leads …

Value (ethics)education.field_of_studyGeneral Immunology and MicrobiologyPopulationSkewGeneral MedicineBiologyGeneral Biochemistry Genetics and Molecular BiologySocial groupSocial systemEconometricsSocial evolutionGeneral Agricultural and Biological ScienceseducationSocial psychologySelection (genetic algorithm)General Environmental ScienceDiversity (business)Proceedings of the Royal Society of London. Series B: Biological Sciences
researchProduct

Feature Selection Approach based on Mutual Information and Partial Least Squares

2014

Feature selection technology can improve the modeling accuracy and reduce model’s complexity, especially for the high dimensional spectral data. Aim at this problem, feature selection approach based on mutual information (MI) and partial least square (PLS) is proposed in this paper. MI values between features and responsible variable are calculated, and the threshold value using to select final features is optimal selected based on PLS algorithm. The numbers of the latent values of the PLS and the threshold value of MI are selected according the modeling performance simultaneously. The experimental results based on the near-infrared spectrum show that the proposed approach has better perfor…

Variable (computer science)Threshold limit valuebusiness.industryPartial least squares regressionGeneral EngineeringPattern recognitionFeature selectionHigh dimensionalArtificial intelligenceMutual informationSpectral databusinessMathematicsAdvanced Materials Research
researchProduct

Variable selection with unbiased estimation: the CDF penalty

2022

We propose a new SCAD-type penalty in general regression models. The new penalty can be considered a competitor of the LASSO, SCAD or MCP penalties, as it guarantees sparse variable selection, i.e., null regression coefficient estimates, while attenuating bias for the non-null estimates. In this work, the method is discussed, and some comparisons are presented.

Variable selection L1-type penalty LASSO SCAD MCP
researchProduct