Розробка системи організації модульної конструкторсько-технологічної підготовки виробництва чавунних поршнів двигунів внутрішнього згоряння

Modern engine building requires a significant increase in power, fuel efficiency and ensuring high environmental performance of internal combustion engines (ICE). When forcing the operating modes of diesel engines, one of the most loaded engine parts becomes a piston, due to a significant increase in mechanical and thermal stresses. With increasing load on the piston, the difficulty of meeting the high demands for them increases. When creating modern ICE and improving the quality of existing ones, special attention is paid to the design and technological preparation of the production of pistons, which is the object of research. Pistons determine the reliability and life of the engine as a whole.To solve this problem, all the main works related to the design and manufacture of cast-iron pistons are proposed to divide into separate modules, performed simultaneously in three areas: organizational, design and technological. These modules are integral sectors of a single modular system for organizing design and technological preparation for production of cast iron pistons. Modeling of the stressed-strain state of monolithic cast-iron pistons is considered for an example of implementation of one of the modules. The results of calculations of the stress-strain state and the temperature distribution field in the body of the piston are presented. The results show that the maximum temperature is 315 °C and concentrated on the edge of the combustion chamber. The stress does not exceed 617 MPa.Предложена система модульной конструкторско-технологической подготовки производства чугунных поршней двигателей внутреннего сгорания (ДВС). Особенностью данной системы является то, что она обеспечивает возможность одновременного выполнения конструкторских, технологических и организационных работ. Показано, что это достигается путем использования модульного принципа проектирования чугунных поршней ДВС. Для примера реализации одного из модулей проведено моделирование напряженно-деформированного состояния монолитных чугунных поршней.Запропоновано систему модульної конструкторсько-технологічної підготовки виробництва чавунних поршнів двигунів внутрішнього згоряння (ДВЗ). Особливістю даної системи є те, що вона забезпечує можливість одночасного виконання конструкторських, технологічних і організаційних робіт. Показано, що це досягається шляхом використання модульного принципу проектування чавунних поршнів ДВС. Для прикладу реалізації одного з модулів проведено моделювання напружено-деформованого стану монолітних чавунних поршнів

Species identification based on a semi-diagnostic marker : Evaluation of a simple conchological test for distinguishing blue mussels Mytilus edulis L. and M. trossulus Gould

Cryptic and hybridizing species may lack diagnostic taxonomic characters leaving researchers with semi-diagnostic ones. Identification based on such characters is probabilistic, the probability of correct identification depending on the species composition in a mixed population. Here we test the possibilities of applying a semi-diagnostic conchological character for distinguishing two cryptic species of blue mussels, Mytilus edulis and M. trossulus. These ecologically, stratigraphically and economically important molluscs co-occur and hybridize in many areas of the North Atlantic and the neighboring Arctic. Any cues for distinguishing them in sympatry without genotyping would save much research effort. Recently these species have been shown to statistically differ in the White Sea, where a simple character of the shell was used to distinguish two mussel morphotypes. In this paper, we analyzed the associations between morphotypes and species-specific genotypes based on an abundant material from the waters of the Kola Peninsula (White Sea, Barents Sea) and a more limited material from Norway, the Baltic Sea, Scotland and the Gulf of Maine. The performance of the "morphotype test" for species identification was formally evaluated using approaches from evidence-based medicine. Interspecific differences in the morphotype frequencies were ubiquitous and unidirectional, but their scale varied geographically (from 75% in the White Sea to 15% in the Baltic Sea). In addition, salinity-related variation of this character within M. edulis was revealed in the Arctic Barents Sea. For every studied region, we established relationships between the proportions of the morphotypes in the populations as well as between the proportions of the morphotypes in samples and the probabilities of mussels of different morphotypes being M. trossulus and M. edulis. We provide recommendations for the application of the morphotype test to mussels from unstudied contact zones and note that they may apply equally well to other taxa identified by semi-diagnostic traits.Peer reviewe

The puzzle of HD 104994 (WR 46)

Intense coordinated spectroscopic and photometric monitoring of the suspected Wolf-Rayet binary WR 46 in 1999 reveals clear periodic variations, P = 0.329 ± 0.013 days, in the radial velocities of the emission lines of highest ionization potential, O VI and N V, found deepest in the Wolf-Rayet wind and thus least likely to be perturbed by a companion. These are accompanied by coherent variability in the profiles of lines with lower ionization/excitation potential and in the continuum flux. Most probably originating from orbital motion of the Wolf-Rayet component of the binary, this periodic radial velocity signal disappears from time to time, thus creating a puzzle yet to be solved. We show that the entangled patterns of the line profile variability are mainly governed by transitions between high and low states of the system's continuum flux.Facultad de Ciencias Astronómicas y Geofísica

The puzzle of HD 104994 (WR 46)

Intense coordinated spectroscopic and photometric monitoring of the suspected Wolf-Rayet binary WR 46 in 1999 reveals clear periodic variations, P = 0.329 ± 0.013 days, in the radial velocities of the emission lines of highest ionization potential, O VI and N V, found deepest in the Wolf-Rayet wind and thus least likely to be perturbed by a companion. These are accompanied by coherent variability in the profiles of lines with lower ionization/excitation potential and in the continuum flux. Most probably originating from orbital motion of the Wolf-Rayet component of the binary, this periodic radial velocity signal disappears from time to time, thus creating a puzzle yet to be solved. We show that the entangled patterns of the line profile variability are mainly governed by transitions between high and low states of the system's continuum flux.Facultad de Ciencias Astronómicas y Geofísica

Встановлення змін технічних параметрів дійкової гуми доїльних апаратів та їх вплив на експлуатаційні характеристики

Nipple rubber is an important part of a milking machine, one of its key elements. This is the only component of a milking plant that has direct contact with the surface of a cow udder. In addition, nipple rubber is the most loaded component of a milking machine. During the milking process, it is compressed and unclenched more than 400 times. In order to maximize the effect of the use of rubber, it is necessary to calculate the conditions of its use correctly, to monitor technical parameters in due time. The task of the study is to establish changes in the technical parameters of the nipple rubber of milking machines and their impact on the performance of the article.In the course of the research, it was established that the service life of all kinds of nipple rubbers was 1,000 hours, which, if used for 8 hours a day, corresponds to 125 days or 4 months of operation. When used for 1,000 hours, the rubber stiffness varies within significant limits and an average is: for products made of silicone 2,849.61±52.23–3,343.76±51.26 N/m; made of the material of rubber mixtures – 2,597.76±78.26–2,821.43±55.24 N/m. The readiness coefficient of all products is 1. Using electron microscopy, it was possible to establish the changes of the inner surface of nipple rubber after operating for 125 days/1,000 hours and after operating for 250 days/2,000 hours. It is proved that all its basic parameters change during operation. The weight of an article changes by 8.5 %, the depth – by 37 %, the wall thickness – by 2.5 %, and the stretching length – by 27 %. The high positive correlation dependence (r=+0.939) between the nipple rubber stiffness and milking intensity was found.The studied indicators are important for determining the performance and nipple rubber suitability for use. The conducted research offers a real possibility of taking into consideration the qualitative parameters of nipple rubber during their selection and subsequent operationСосковая резина – важная часть доильного аппарата, одна из его ключевых элементов. Это тот единственный компонент доильной установки, который имеет непосредственный контакт с поверхностью вымени коров. Наряду с этим, сосковая резина – это самый нагруженный компонент доильного аппарата. За время процесса доения она сжимается и разжимается более 400 раз. С целью максимального эффекта от использования сосковой резины, необходимо правильно рассчитать условия ее использования, своевременно осуществлять контроль технических параметров. Задача исследования заключается в установлении изменений технических параметров сосковой резины доильных аппаратов и их влияния на эксплуатационные характеристики изделия.В ходе исследований установлено, что работоспособность всех сосковых резин составила 1000 часов, что при наработке в день восьми часов соответствует 125 дням или 4 месяцам эксплуатации. При наработке в 1000 часов жесткость сосковой резины колеблется в значительных пределах и в среднем составляет: для изделий из силикона 2849,61±52,23 – 3343,76±51,26 Н/м; с материала резиновых смесей – 2597,76±78,26 – 2821,43±55,24 Н/м. Коэффициент готовности всех изделий составляет 1. При использовании электронной микроскопии установлены изменения внутренней поверхности сосковой резины после наработки 125 дней/1000 часов и после эксплуатации в течение 250 дней/2000 часов. Доказано, что изменениям во время эксплуатации сосковой резины подвергаются все основные ее параметры. Масса изделия изменяется на 8,5 %, глубина – на 37 %, толщина стенок – 2,5 %, а длина растяжения – на 27 %. Между жесткостью сосковой резины и интенсивностью молокоотдачи установлена высокая положительная корреляционная зависимость (r=+0,939).Исследованные показатели важны в определении работоспособности и пригодности сосковой резины к использованию. Проведенные исследования представляют реальную возможность учета качественных параметров сосковой резины доильных аппаратов при выборе и дальнейшей эксплуатацииДійкова гума – важлива частина доїльного апарату, один з його ключових елементів. Це той єдиний компонент доїльної установки, який має безпосередній контакт з  поверхнею вимені корів. Поряд з цим, дійкова гума – це самий навантажений компонент доїльного апарату. За час процесу доїння вона стискається і розтискається понад 400 разів. З метою максимального ефекту від використання дійкової гуми, необхідно правильно розрахувати умови її використання, своєчасно здійснювати контроль технічних параметрів. Завдання дослідження полягає у встановленні змін технічних параметрів дійкової гуми доїльних апаратів та їх впливу на експлуатаційні характеристики виробу.В ході досліджень встановлено, що працездатність всіх дійкових гум склала 1000 годин, що при напрацюванні в день восьми годин відповідає 125 дням або 4 місяцям експлуатації. При напрацюванні в 1000 годин жорсткість дійкової гуми коливається в значних межах і в середньому становить: для виробів з силікону 2849,61±52,23–3343,76±51,26 Н/м; з матеріалу гумових сумішей – 2597,76±78,26–2821,43±55,24 Н/м. Коефіцієнт готовності усіх виробів становить 1. За використання електронної мікроскопії встановлено зміни внутрішньої поверхні дійкової гуми після напрацювання 125 днів/1000 годин та після експлуатації протягом 250 днів/2000 годин. Доведено, що змінам під час експлуатації дійкової гуми піддаються всі основні її параметри. Маса виробу змінюється на 8,5 %, глибина – на 37 %, товщина стінок – 2,5 %, а довжина розтягнення – на 27 %. Між жорсткістю дійкової гуми та інтенсивністю молоковіддачі встановлено високу позитивну кореляційну залежність (r=+0,939).Досліджені показники є важливими у визначенні працездатності та придатності дійкової гуми до використання. Проведені дослідження представляють реальну можливість врахування якісних параметрів дійкової гуми доїльних апаратів під час вибору та подальшої експлуатаці

The puzzle of HD 104994 (WR 46)

Intense coordinated spectroscopic and photometric monitoring of the suspected Wolf-Rayet binary WR 46 in 1999 reveals clear periodic variations, P = 0.329 ± 0.013 days, in the radial velocities of the emission lines of highest ionization potential, O VI and N V, found deepest in the Wolf-Rayet wind and thus least likely to be perturbed by a companion. These are accompanied by coherent variability in the profiles of lines with lower ionization/excitation potential and in the continuum flux. Most probably originating from orbital motion of the Wolf-Rayet component of the binary, this periodic radial velocity signal disappears from time to time, thus creating a puzzle yet to be solved. We show that the entangled patterns of the line profile variability are mainly governed by transitions between high and low states of the system's continuum flux.Facultad de Ciencias Astronómicas y Geofísica

DEVELOPMENT OF LOGISTICS SUPPORT IN UKRAINE

In the article defined the dominant role of logistics - inclusion Logistics Performance Index to identify International Indices of the national economy.The concept of logistics, the stages of its formation and development function. Highlight specific factors that accelerate or suspended national logistics system development software for a specific period. The current state of logistics software, its challenges and opportunities. Compared to the development of the logistics system of Ukraine CIS countries and Europe. Thesis there is determined factors of positive and negative influence on logistics support. It was established the need for innovation in logistics. It is proved that the realization of production and industry need logistic support already producing way of achieving their goals. Priority and emphasized the need to implement existing logistics capacity.Undoubtedly, the process of Ukraine's integration into the global economy involves the creation of powerful logistics associations, but in the way it faces a number of factors that need immediate deployment

Effect of recombinant Sox9 protein on the expression of cartilage-specific genes in human dermal fibroblasts cell culture

Introduction: Damage to the hyaline layer of large joints resulting from injuries or age-related changes restricts their mobility. The repair of these disorders is an actual issue in medicine. One of the promising therapies is the usage of cell engineering constructs based on a biodegradable scaffold and a modified cell culture. A frequently used method to modify the proliferation of cell culture for tissue engineering of hyaline cartilage, which makes it possible to introduce an experimental technique into clinical practice, is the application of recombinant proteins that affect chondrogenesis and lead to increase synthesis of extracellular matrix proteins. The goal of this work was to elucidate the effect of the key transcription factor in the chondrogenesis process – Sox9 protein – on the expression of genes responsible for chondrogenesis (Tgfβ3, Sox9, Acan, Comp, Col2a1). Materials and methods: Human dermal fibroblasts were used as a cell culture; recombinant Sox9 was added at each change of medium; the modification was carried out for 21 days, and difference in gene expression was determined by real-time PCR and -ΔΔCt method. Results and discussion: To assess the effectiveness of fibroblast modification, we analyzed the changing of expression of genes responsible for chondrogenesis (Tgfß3, Sox9, Col2a1, Acan, Comp). We studied the direct effect of different concentrations of the recombinant Sox9 protein on the proliferation of dermal fibroblasts in the chondrogenic direction. We showed that the addition of the recombinant Sox9 protein in various concentration did not significantly change the expression of both the genes encoding proteins of the extracellular matrix of hyaline cartilage (Acan, Col2a1, Comp) and the genes encoding chondrogenesis inducers (Tgfß3, Sox9). Conclusion: As a result of the experiments, it was shown that the recombinant Sox9 protein has practically no effect on chondrogenic differentiation and does not significantly change the expression of chondrogenesis genes

Systematic bias of average winter-time land surface temperatures inferred from MODIS at a site on Svalbard, Norway

Thermal remote sensing can quantify climate change in the Arctic, where ground-based measurements continue to be rare. The land surface temperature (LST) is accessible on the pan-arctic scale through a number of remote sensing platforms, such as the “Moderate Resolution Imaging Spectrometer” (MODIS). This study compares remotely sensed LST from MODIS to ground-based point measurements of the snow surface temperature on Svalbard for seven consecutive winters, thus covering more than half of the winter seasons in the operation period of MODIS Terra and Aqua. We find a systematic negative bias of the average winter surface temperature computed from single LST measurements between 1.5 and 6 K, with a mean bias of 3 K. The bias consistently occurs both for the MODIS L2 and for the daily and eight-day MODIS L3 products, which is explained by two reasons: i) During winter on Svalbard, cold surface temperatures are associated with clear-sky conditions, while warm surface temperatures typically occur during overcast periods. This leads to an overrepresentation of cold temperature in averages computed from remotely sensed LST measurements. ii) The MODIS cloud detection scheme fails to recognize some cloud-covered or partially cloud-covered situations, thus leading to admixing of colder cloud top temperatures. Both effects contribute equally to the total average bias accumulated over the winter season, with effect (i) dominating in some winters, while the observed bias can be fully explained by (ii) in other winters

Effect of recombinant Sox9 protein on the expression of cartilage-specific genes in human dermal fibroblasts cell culture

Introduction: Damage to the hyaline layer of large joints resulting from injuries or age-related changes restricts their mobility. The repair of these disorders is an actual issue in medicine. One of the promising therapies is the usage of cell engineering constructs based on a biodegradable scaffold and a modified cell culture. A frequently used method to modify the proliferation of cell culture for tissue engineering of hyaline cartilage, which makes it possible to introduce an experimental technique into clinical practice, is the application of recombinant proteins that affect chondrogenesis and lead to increase synthesis of extracellular matrix proteins. The goal of this work was to elucidate the effect of the key transcription factor in the chondrogenesis process – Sox9 protein – on the expression of genes responsible for chondrogenesis (Tgfβ3, Sox9, Acan, Comp, Col2a1). Materials and methods: Human dermal fibroblasts were used as a cell culture; recombinant Sox9 was added at each change of medium; the modification was carried out for 21 days, and difference in gene expression was determined by real-time PCR and -ΔΔCt method. Results and discussion: To assess the effectiveness of fibroblast modification, we analyzed the changing of expression of genes responsible for chondrogenesis (Tgfß3, Sox9, Col2a1, Acan, Comp). We studied the direct effect of different concentrations of the recombinant Sox9 protein on the proliferation of dermal fibroblasts in the chondrogenic direction. We showed that the addition of the recombinant Sox9 protein in various concentration did not significantly change the expression of both the genes encoding proteins of the extracellular matrix of hyaline cartilage (Acan, Col2a1, Comp) and the genes encoding chondrogenesis inducers (Tgfß3, Sox9). Conclusion: As a result of the experiments, it was shown that the recombinant Sox9 protein has practically no effect on chondrogenic differentiation and does not significantly change the expression of chondrogenesis genes