The approach to building the algorithm for controlling rotor motion in a hybrid mechatronic bearing

The paper describes the approach to building the algorithm for controlling the rotor motion in a hybrid mechatronic bearing. Such bearings include a rolling bearing, a gas foil bearing, an electromagnetic and a piezo actuator. Fuzzy logic techniques are used in the proposed algorithm. Its main aim is to minimize the deviation of the rotor position in the bearing from the equilibrium position. It results in reducing the vibrational activity of the rotor-bearing system and reducing the friction losses

Molecular versus excitonic disorder in individual artificial light-harvesting systems

Natural light-harvesting antennae employ a dense array of chromophores to optimize energy transport via the formation of delocalized excited states (excitons), which are critically sensitive to spatio-energetic variations of the molecular structure. Identifying the origin and impact of such variations is highly desirable for understanding and predicting functional properties yet hard to achieve due to averaging of many overlapping responses from individual systems. Here, we overcome this problem by measuring the heterogeneity of synthetic analogues of natural antennae-self-assembled molecular nanotubes-by two complementary approaches: single-nanotube photoluminescence spectroscopy and ultrafast 2D correlation. We demonstrate remarkable homogeneity of the nanotube ensemble and reveal that ultrafast (∼50 fs) modulation of the exciton frequencies governs spectral broadening. Using multiscale exciton modeling, we show that the dominance of homogeneous broadening at the exciton level results from exchange narrowing of strong static disorder found for individual molecules within the nanotube. The detailed characterization of static and dynamic disorder at the exciton as well as the molecular level presented here opens new avenues in analyzing and predicting dynamic exciton properties, such as excitation energy transport

Анархія як політико-правова доктрина: історія та сучасність

Розвиток сучасного світу та його всюди суща глобалізація має декілька теорій розвитку, серед яких є досить оптимістичні: створення єдиної земної держави, колонізація космосу, створення планетарних організацій. Але є і досить песимістичний варіант майбутнього – кіберпанк з всюди сущою владою транснаціональних корпорацій та фактичною відсутністю влади з боку держави

Algorithms for anomaly detection in data from clinical trials and health registries

This master's thesis deals with the problems of anomalies detection in data from clinical trials and medical registries. The purpose of this work is to perform literary research about quality of data in clinical trials and to design a personal algorithm for detection of anomalous records based on machine learning methods in real clinical data from current or completed clinical trials or medical registries. In the practical part is described the implemented algorithm of detection, consists of several parts: import of data from information system, preprocessing and transformation of imported data records with variables of different data types into numerical vectors, using well known statistical methods for detection outliers and evaluation of the quality and accuracy of the algorithm. The result of creating the algorithm is vector of parameters containing anomalies, which has to make the work of data manager easier. This algorithm is designed for extension the palette of information system functions (CLADE-IS) on automatic monitoring the quality of data by detecting anomalous records

Внутрішньоканальна інкорпорація сухожилкового автотрансплантата передньої схрещеної зв’язки з імплантацією поліпропіленової сітки за даними МРТ

Hamstring tendon graft remains one of the most popular for ACL reconstruction (ACLR). However, its disadvantage is long term ligamentation process and intracanal incorporation and delayed rehabilitation. One of the methods for stimulation of connective tissue growth is the implantation of polypropylene mesh (PPM), which are widely used in hernioplasty. Objective. To compare the MRI data dynamics of intracanal incorporation of tendon graft with implantation of PPM in bone canals. Methods. For evaluation of graft reconstruction in the femoral and tibial canals we used criteria based on the analysis of MRI images in PD FS and STIR sequences: the nature of the signal from the graft in the center of bone canal; general view of the graft; the nature of the MRI signal from the tissues around the graft on the tendons-bone border; the pre­sence of synovial fluid in the canals and bone edema around them. Results of MRI of 75 patients who underwent «all-inside» ACLR with semitendinosus graft were analyzed. In the study group (40 patients) were compared to control group (35 patients) additionally implanted PPM around the ends of the tendon graft. Results. Intracanal graft incorporation in the group of patients with implantation of PPM occurred faster. The nature of the signal from the center of the bone canal and on the bone-tendon border progressed significantly faster in all observed terms. In the research group there was not presence of synovial fluid in the canals along the graft. Conclusions. Implantation of PPM around the ends of the ACL tendon autograft immersed in bone canals, leads, according to MRI data, to faster intra-canal incorporation. Key words. Knee joint, anterior cruciate ligament, arthroscopy.Трансплантат із сухожилків згиначів гомілки залишається одним із найпопулярніших для пластики передньої схрещеної зв’язки (ПСЗ). Проте його недоліком є тривалий процес лігаментації та внутрішньоканальної інкорпорації, що затримує реабілітацію. Одним із методів стимуляції росту сполучної тканини є імплантація поліпропіленових сіток (ПС), які широко застосовують у герніопластиці. Мета. Провести порівняльний аналіз МРТ-динаміки внут­рішньоканальної інкорпорації сухожилкового трансплантата з імплантацією ПС у кісткових каналах. Методи. Для оцінювання перебудови трансплантата в каналах стегнової та великогомілкової кісток використовували критерії, засновані на аналізі зображень МРТ у PDFS і STIR послідовностях: характер сигналу від трансплантата по центру кісткового каналу; загальний вигляд трансплантата; характер МРТ-сигналу від тканин навколо трансплантата на межі «сухожилок – кістка»; наявність синовіальної рідини в кісткових каналах і кісткового набряку навколо них у стегновій і великогомілковій кістках. Проаналізовано результати МРТ 75 пацієнтів, яким виконана пластика ПСЗ методом «all-inside» автотрансплантатом із сухожилка напівсухожилкового м’яза. У групі дослідження (40 осіб) на відміну від групи порівняння (35) додатково імплантували ПС навколо кінців сухожилкового трансплантата. Результати. Внутрішньоканальна перебудова трансплантата в групі пацієнтів з імплантацією ПС відбувалася швидше. Характер сигналу по центру кісткового каналу і на межі сухожилка з кісткою прогресував достовірно швидше в усі терміни спостереження. У групі дослідження практично не реєстрували затікання рідини уздовж транс­плантата в кісткові канали. Висновки. Імплантація ПС навколо кінців сухожилкового автотрансплантата ПСЗ, занурених у кісткові канали, приводить, за даними МРТ, до його швидшої внутрішньоканальної інкорпорації. Ключові слова. Колінний суглоб, передня схрещена зв’язка, артроскопі

Analysis of argon isotope separation by low temperature adsorption

In this work, the estimated calculated values of the critical parameters of argon isotopes 36Ar, 38Ar, 40Ar and the corresponding values of the constants of the Van der Waals, Redlich-Kwong and Peng-Robinson equations of state are obtained. The data obtained make it possible to calculate the adsorption isotherms of argon isotopes on microporous adsorbents. The technique proposed for obtaining analytical expressions for the adsorption isotherms of argon isotopes at cryogenic temperatures makes it possible to estimate the degree of influence of the pressure of the isotope mixture and its composition on the mixture separations coefficients

Analysis of argon isotope separation by low temperature adsorption

In this work, the estimated calculated values of the critical parameters of argon isotopes 36Ar, 38Ar, 40Ar and the corresponding values of the constants of the Van der Waals, Redlich-Kwong and Peng-Robinson equations of state are obtained. The data obtained make it possible to calculate the adsorption isotherms of argon isotopes on microporous adsorbents. The technique proposed for obtaining analytical expressions for the adsorption isotherms of argon isotopes at cryogenic temperatures makes it possible to estimate the degree of influence of the pressure of the isotope mixture and its composition on the mixture separations coefficients

Method for On-Line Remaining Useful Life and Wear Prediction for Adjustable Journal Bearings Utilizing a Combination of Physics-Based and Data-Driven Models: A Numerical Investigation

RUL (remaining useful life) estimation is one of the main functions of the predictive analytics systems for rotary machines. Data-driven models based on large amounts of multisensory measurements data are usually utilized for this purpose. The use of adjustable bearings, on the one hand, improves a machine’s performance. On the other hand, it requires considering the additional variability in the bearing parameters in order to obtain adequate RUL estimates. The present study proposes a hybrid approach to such prediction models involving the joint use of physics-based models of adjustable bearings and data-driven models for fast on-line prediction of their parameters. The approach provides a rather simple way of considering the variability of the properties caused by the control systems. It has been tested on highly loaded locomotive traction motor axle bearings for consideration and prediction of their wear and RUL. The proposed adjustable design of the bearings includes temperature control, resulting in an increase in their expected service life. The initial study of the system was implemented with a physics-based model using Archard’s law and Reynolds equation and considering load and thermal factors for wear rate calculation. The dataset generated by this model is used to train an ANN for high-speed on-line bearing RUL and wear prediction. The results show good qualitative and quantitative agreement with the statistics of operation of traction motor axle bearings. A number of recommendations for further improving the quality of predicting the parameters of active bearings are also made as a summary of the work

Heteroleptic Zn(II)–Pentaiodobenzoate Complexes: Structures and Features of Halogen–Halogen Non-Covalent Interactions in Solid State

Reactions between Zn(II) nitrate, pentaiodobenzoic acid (HPIBA) and different pyridines in dimethylformamide (DMF) result in the formation of the heteroleptic neutral complexes [Zn(3,5-MePy)2PIBA2] (1) and [Zn(DMF)3(NO3)PIBA] (2). Both compounds were isolated in pure form, as shown by the PXRD data. The features of specific non-covalent interactions involving halogen atoms (halogen bonding) were examined by means of DFT calculations (QTAIM analysis and the estimation of corresponding energies)