National Repository of Grey Literature 82 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Evolution strategies for policy optimization in transformers
Lorenc, Matyáš ; Neruda, Roman (advisor) ; Pilát, Martin (referee)
We explore the capability of evolution strategies to train a transformer architecture in the reinforcement learning setting. We perform experiments using OpenAI's highly parallelizable evolution strategy and its derivatives utilizing novelty and quality-diversity searches to train Decision Transformer in Humanoid locomotion environment, testing the ability of these black-box optimization techniques to train even such relatively large (com- pared to the previously tested in the literature) and complicated (using a self-attention in addition to fully connected layers) models. The tested algorithms proved to be, in gen- eral, capable of achieving strong results and managed to obtain high-performing agents both from scratch (randomly initialized model) and from a pretrained model. 1
Automation for welding cell
Lorenc, Michal ; Stibor, Karel (referee) ; Štohl, Radek (advisor)
The work deals with automation, safety and control of the welding cell. At the beginning the possibilities of communication between the PLC and the robot are discussed. Then the work moves on to the definition of the cell requirements and the design of the function concept. This design is followed by a risk assessment which is followed by the design of risk reduction measures, including the design of the specific equipment used. This moves the work to the design and implementation of the control program for the PLC and HMI. The safety features proposed in the welding cell safety section are also addressed in the program. Following the implemented control program, a verification plan is designed and evaluated. And in the last section, suggestions for further development of the welding cell are written and the achieved results are summarized at the end.
Bifunctional ligands for copper(II) complexation
Benešová, Martina ; Kotek, Jan (advisor) ; Lorenc, Miroslav (referee)
The main aim of this thesis was preparation of makrocyclic ligand based on 1,4,8,11- tetraazacyklotetradecane skeleton, which is suitable for selective complexation of divalent copper. Cyclam macrocycle bears one weakly coordinating aminobenzylphospinate pendant arm (compound L). During the synthesis was the skeleton asymmetrically protected in positions 1,4 and 8. Attachment of phospinate pendant arm was tried with the corresponding Mannich reaction of ethyl or bis(trimethylsilyl) esters 4-nitrobenzylphosphinic acid and alkylation using mesyl ester derived from hydroxomethyl(4-nitrobenzyl)phosphinic acid (benzyl O- methylsulfonylhydroxymethyl(4-nitrobenzyl)phosphinate). In the frame of this work the synthesis of the targeted product was developed. Reproducibility was also verified for synthesis of cyclam and its asymmetrical protection in three positions. Furthermore, a study of the kinetics of de-protection of cyclam skeleton and pendant arm using basic and acid hydrolysis was done. NHNH NH N P O NH2 OH ( L ) KEYWORDS Cyclam, phosphinates, nuclear medicine, copper(II) complexes.
Bifunctional ligands for copper(II) complexation
Paúrová, Monika ; Kotek, Jan (advisor) ; Lorenc, Miroslav (referee)
In this Bachelor thesis, cyclam bifunctional derivatives bearing pendant phosphonate groups [4-methyl-11-p-carboxybenzyl-1,4,8,11-tetraazacyclotetradecane-1,8-bis(methylenephosphonic acid) and 4-methyl-11-p-nitrobenzyl-1,4,8,11-tetraazacyclotetradecane-1,8-bis(methylenephosphonic acid)], were prepared and studied as a potential ligands for complexation of divalent copper ion. These ligands can to be used as macromolecular carriers. Vytvořeno pomocí Software602 Print2PDF 8. Tuto řádku odstraníte zakoupením licence a aktivací na http://www.software602.cz/
Aminocarbonydrates as part of cyclic polyamines
Vacková, Zuzana ; Lorenc, Miroslav (advisor) ; Veselý, Jan (referee)
Magnetic resonance imaging is one of the imaging methods that are needed in medicine for diagnostic purposes. This method neither exposes the patient to X-rays, nor any other negative effects on the human organism are known by then. Another significant advantage of MRI is its ability to achieve high contrast even between structurally very similar tissues. The contrast agents commonly used with the magnetic resonance imaging help heighten this ability. Part of these contrast agents is a metal ion, the ion gadolinium (GdIII) is the most commonly used nowadays. But it must be complexed by a suitable ligand. This work deals with the synthesis of a number of potentially suitable model ligands. The saccharide component is even a part of these ligands. This component should enable to achieve a greater solubility of the complex or the possibility of linking other additional saccharide units, another ligand or a detecting group. Several theoretical paths leading to the final fabric were created. Not all of them led to the target, only one was successful. The produced macrocycle is the potentially applicable ligand for complexation with GdIII or other metal ion, it means a good part of the new potential contrast agent.
Design and synthesis of selective gallium(III) chelators
Krchová, Tereza ; Kotek, Jan (advisor) ; Lorenc, Miroslav (referee)
This bachelor thesis is focused on the preparation of two new ligands (based on the 1-oxa-4,7-diazacyclononane skeleton), which would be potentially suitable for fast and selective complexation of Ga(III). Complexes of these ligands could find applications in radiodiagnostics (PET, SPECT), or as a new class of contrast agents for MRI based on proton chemical exchange saturation transfer (CEST). This thesis also describes the preparation of 1-oxa-4,7-diazacyclononane and attempts of preparation of N-benzyloxycarbonylaziridine. Thesis also includes a description of radiodiagnostic and radiotherapeutic methods of nuclear medicine. It also discusses the method of magnetic resonance tomography (MRI), especially the method using CEST contrast agents. Thesis contains an overview of the use of Ga(III) radioisotopes in radiomedicine.

National Repository of Grey Literature : 82 records found   1 - 10nextend  jump to record:
See also: similar author names
3 Lorenc, Marek
1 Lorenc, Marián
2 Lorenc, Martin
2 Lorenc, Matyáš
4 Lorenc, Michal
2 Lorenc, Miroslav
Interested in being notified about new results for this query?
Subscribe to the RSS feed.