bluuebunny/crossref_metadata_2025 huggingface dataset:
Nikczemne skrzaty i inne (nie)baśniowe potworności dzieciństwa w „Złodziejach snów” Małgorzaty Strękowskiej-Zaremby
Authors: Skowera Maciej
Published: December 2021

The first part of the article provides a short outline of the works by Małgorzata Strękowska-Zaremba, a well-known and critically acclaimed Polish children’s author, and gives special attention to her interest in certain popular literature genres. Among her works, a prominent place is occupied by three books in which the writer uses various genres and conventions of the fantastic to discuss important real-life problems: parents’ divorce and homelessness in Złodzieje snów [The Dream Stealers] (2008/2019), domestic violence in Dom nie z tej ziemi [The Otherworldly House] (2017), and depression in Lilana (2019). The main part of the paper covers an analysis of Złodzieje snów, which is focused on monsterological plots and motifs shown in the context of the use of fairytale conventions in the book. Strękowska-Zaremba utilises the figure of demonic gnomes (derived from French folklore) who in the story are believed to have stolen the dreams of the protagonist, little Basia, after her parents separated. However, as the author of the article claims in its last part, in Złodzieje snów, these creatures from the folk imagery are much less monstrous than real-life problems, including separation and divorce, loneliness, and homelessness. This also applies to Dom nie z tej ziemi and Lilana, which is briefly stated in the conclusion.
Czy teza o niedookreśleniu teorii przez dane doświadczenia czyni sukcesy nauki cudem?
Authors: Kotowski Mateusz
Published: December 2021

In his book Struktura rewolucji relatywistycznej i kwantowej w fizyce [The Structure of Relativistic and Quantum Revolution in Physics] Wojciech Sady presents a view on the thesis of underdetermination, according to which it should be regarded as a pseudoproblem of contemporary philosophy of science. I reject this view and suggest that Sady’s argumentation against the thesis of underdetermination is tantamount to attacking a straw man. This is because he argues against its correctness by pointing to the incorrectness of the conclusions he unjustifiably draws from it.
Fisher consistent estimation of regression parameter in the proportional mean residual life model with frailty
Authors: Skolimowska-Kulig Magdalena
Published: December 2021

In the article, we consider the Fisher consistent estimation of the regression parameters in the proportional mean residual life model with arbitrary frailty. It is discussed that conventional estimation procedures, such as the maximum likelihood estimation or Cox’s approach, which are employed in common regression models, may also yield consistent inference in the extended models.
Anadolu'da Bir Sadrazam Müessesesi: Kütahya Rüstem Paşa Medresesi
Authors: ÇİFTÇİ Mehdin
Published: December 2021

Islahatçılığıyla Osmanlı Devleti’nin siyasî ve malî gelişmesine önemli katkılarda bulunan ve dönemindeki iktidar mücadelelerinde aktif rol alması gibi sebeplerle de eleştirilen Kanûnî Sultan Süleyman devri sadrazamlarından Rüstem Paşa, kurduğu vakıflarla Hırvatistan, Macaristan, Balkanlar, Rumeli, İstanbul, Anadolu, Mısır, Medine ve Kudüs gibi Osmanlı’nın farklı coğrafyalarında birçok hayır eseri yaptırmıştır. Onun yaptırdığı eserlerden biri de Kütahya Rüstem Paşa Medresesi’dir. 945-946 (1538-1539) tarihleri arasında merkezi Kütahya olan Anadolu beylerbeyiliği görevinde de bulunan Rüstem Paşa bu medreseyi, kısa süreli bu görevi esnasında değil de daha sonra birinci sadrazamlığı devrinde yaptırmıştır. Kütahya’da başka hayır eserleri de yaptıran Rüstem Paşa’nın bu medresesi, 957 (1550) tarihinde İstanbul’daki medresesiyle aynı yılda inşa edilmiştir. Açık avlulu klasik Osmanlı mimarisiyle inşa edilen ve toplam on hücre ile bir dershaneden oluşan medrese, geçirdiği bazı restorasyonlarla günümüze ulaşmıştır. Mimar Sinan’ın mimarbaşı olarak imparatorluğun her yanındaki yapılardan sorumlu olduğu bir dönemde inşa edilen bu medrese, Mimar Sinan tezkirelerinde ve ona ait olduğu düşünülen isimsiz risalede geçmemektedir. Bu makalede, Osmanlı’nın en kudretli sadrazamlarından biri ve aynı zamanda Kanûnî’nin damadı olan Rüstem Paşa’nın ilgili medresesinin vakfiyesi, tarihçesi ve personeli gibi birçok yönü incelenerek Anadolu’daki bir Osmanlı eğitim kurumu gün yüzüne çıkarılmaya çalışılmıştır.
Başlangıçtan Yirminci Yüzyılın İlk Yarısına Kadar İslâmî Yazımda Cihad Literatürü
Authors: ÇOBAN Mehmet
Published: December 2021

Cihadın mana, boyut ve uygulamasına bakıldığında genel olarak Allah yolunda can ve mal ile mücadele etmek şeklinde tanımı yapılabilir. Cihad, Kur’an ve sünnetin üzerinde önemle durduğu temel meselelerden biridir. Hem teorik hem de pratik bir mesele olan cihad konusu ile ilgili ilk dönemden günümüze kadar pek çok çalışma yapılmış olup zengin bir literatür oluşturulmuştur. Bu araştırmada, ilk asırlardan yirminci yüzyılın ilk yarısına kadar söz konusu alanla ilgili yazılan literatür ele alınacaktır. Mevcut akademik çalışmalarda genel olarak hadis ilmi özelinde Kitâbü’l-cihad edebiyatı ve belli dönemlerde yazılan cihad risaleleri incelenir. Bu çalışmada ise İslâm hükümlerinin mükellefler üzerindeki yansımasını konu edinen fıkıh ilminde cihad konusunun nasıl ele alındığı, fıkıh mezhepleri arasında bu yazım alanında hangi mezhebin daha ağırlıkta olduğu, cihad yazımının tarih boyunca hangi yüzyıllarda ve merkezlerde yoğunlaştığı hususları araştırılacaktır. Bununla birlikte yirminci yüzyılın ilk yarısına kadar risale ve kitap olarak kaleme alınan cihad literatürünün bir bütün olarak dökümü ortaya konulacaktır.
In the article
Authors: Рахмати Ахмад  , Дмитрий Николаевич Зинченко
Published: December 2021

In the article the comparative analysis of possible performance characteristics LA with bearing surfaces of various types. In this paper, a comparison of the results of numerical simulation and physical experiments for three different types of bearing surfaces: the direct and the disc-shaped wings, a ring bearing surface of the closed type and the results of the test tube model aircraft general purpose of the classical scheme (Aeroprakt A-20).
Equations of motion of masses of the Chelomey pendulum model
Authors: Kryshchuk N.
Published: December 2021

To verify the provisions stated by V.I. Bogomolov, B.I. Puzanov. and Linevich E.I. about the possibility of performing over-unit work by inertial forces, a closed mechanical system in the form of kinematically connected rotating masses is proposed for consideration. The research aimed, within the framework of Newtonian mechanics, to study the fulfillment of the laws of conservation of momentum, angular momentum and energy, to establish the possibility of performing work by inertial forces (centrifugal and Coriolis), to assess the change in kinetic parameters using the example of the Chelomey pendulum model. For the complex radial-circular motion of the masses of the Chelomey pendulum model, resolving equations are obtained. To verify the analytical calculations, algorithms for numerical solutions of the above problems have been developed and implemented in the MathCAD software package
Особливості формування позитивного контенту в соціальних мережах під час домінування панічних настроїв населення
Authors: Балюн О. О. , Проданчук О. В.
Published: December 2021

У статті пропонується розглянути вплив негативної та недостовірної інформації про пандемію коронавірусу COVID-19 на психологічне здоров’я українців, що спричиняє формування панічних настроїв серед населення. З’ясовано, що наслідком цілеспрямованого впливу різних комунікаційних технологій стала психоемоційна де­ста­білізація людини, що виявлялось у підвищеному рівні тривожності, посиленні паніч­них настроїв населення. Виявлено, що одним із головних каналів розповсюдження інфодемії стали соціальні мережі.
Чутки як соціокомунікаційний феномен
Authors: Юркова О. А.
Published: December 2021

У статті розглянуто особливості феномену чуток, обставини, за яких вони виникають, суспільну роль, яку вони виконують. Наведено стислий аналіз ключових етапів вивчення феномену чуток у різні історичні періоди. Відповідно до цього виокремлено головні характеристики та спроби систематизації чуток на різних етапах розвитку наукової думки. Зроблено висновок, що чутки є особливим жанром комунікації зі специфічними характеристиками.  Поява, розповсюдження та потенційні наслідки чуток аналізуються з точки зору масових комунікацій з урахуванням напрацювань суміжних наук. Використано доробок науковців у царині психології, соціальної психології, соціології, історії, політичних технологій, реклами.  Окрему увагу приділено новітній проблематиці, пов’язаній з особливостями й наслідками поширення чуток у соціальних мережах.
Потенціал соціальних мереж у контексті функціонування сучасної студентської періодики
Authors: Скороход Т. О. , Смола Л. Є.
Published: December 2021

У статті досліджено рівні використання потенціалу соціальної мережі Фейсбук редакціями українських студентських періодичних видань. Відповідно до першого рівня, редакції студентської періодики використовують соціальні мережі для ретрансляції новин, статей із друкованого видання або постатейного дублювання електронних версій видань. Відповідно до другого рівня, використання соціальних мереж для функціонування студентських редакцій стосується створення інтерактивного майданчика для комунікації з читачами. Виявлено, що за допомогою різних форм контенту колектив студентських видань прагне не тільки поінформувати читача про певні організаційні аспекти своєї діяльності, мотивувати до прочитання, але й емоційно вплинути на нього, налаштувати на інтерактивну комунікацію, залучити його до співтворення видання.
Ускладнювальні фактори комунікації під час пандемії
Authors: Говера О. І.
Published: December 2021

У статті розглянуто, як змінюються елементи комунікативної моделі Гарольда Лассвелла за умов поширення інформації під час пандемії. Модель Лассвелла передбачає, що шлях інформації від суб’єкта (комуніканта) до суб’єкта (комуніката) формується за формулою SMCRE: хто (sourse) виступає у ролі комуніканта, що (message) він транслює, яким каналом (channel), кому (recipient) та з яким ефектом (effect). Результатом дослідження стала систематизація цих ускладнювальних факторів комунікації на різних етапах взаємодії комуніканта з комунікатом.
Синтез плоских хвилеводних антенних решіток з урахуванням взаємного впливу випромінювачів
Authors: Андрійчук Михайло І. , Мельник Михайло Р.
Published: December 2021

Для розв’язання задачі синтезу плоскої прямокутної решітки з хвилеводним збудженням її елементів використано варіаційний підхід. Запропонований функціонал включає три доданки, які дають змогу мінімізувати середньоквадратичне відхилення заданої та синтезованої амплітудних діаграм спрямованості (ДС), значення амплітуди поля в заданих областях ближньої зони, та норму коефіцієнтів збудження елементів решітки. При розв’язанні відповідної електродинамічної задачі аналізу враховується взаємний вплив випромінювачів решітки. Для визначення розподілу струму в випромінювачах решітки використовується інтегральне рівняння типу Халлена. Оптимальні коефіцієнти збудження випромінювачів визначені шляхом мінімізації запропонованого функціоналу, що зводиться до розв’язання системи нелінійних інтегральних рівнянь Ейлера, оскільки вхідними даними задачі є амплітудні характеристики випромінювання. Отримана система нелінійних інтегральних рівнянь розв’язується ефективно методом послідовних наближень, характерною властивістю якого є релаксаційність. Результати обчислень показали, що розроблений підхід може бути використаний для решіток з різною геометрією, зокрема з гексагональним розміщенням випромінювачів.
Разрежение спектра собственных колебаний открытого двухзеркального резонатора с помощью модоселективных рассеивателей на поверхности одного из зеркал
Authors: Пазынин Вадим Леонидович
Published: December 2021

В статье предложена эффективная процедура разрежения спектра собственных колебаний двухзеркальных открытых резонаторов (ОР), основанная на размещении рассеивателей со специально подобранным геометрическим профилем на поверхности одного из зеркал, и образующих с ним единый модоселективный отражатель. С помощью этой процедуры для ОР с плоским и цилиндрическим зеркалами синтезированы два профиля таких рассеивателей. Один из них представляет собой прямоугольный металлический брус, другой — отражатель уголковоэшелеттного типа с тремя симметричными относительно плоскости симметрии резонатора ступенями прямоугольной формы. Геометрия этих рассеивателей подобрана так, чтобы при размещении на плоском зеркале ОР они оказывали минимальное влияние на пространственно-частотные характеристики рабочего собственного колебания, и существенным образом понижали добротность большинства остальных. Рассчитаны спектральные характеристики ОР с такими вставками при возбуждении как токовым источником, так и собственной модой подводящего волновода. Показана возможность существенного уменьшения числа собственных колебаний ОР, по сравнению с резонатором без таких рассеивателей. При использовании рассеивателя уголковоэшелетного типа наблюдался эффект увеличения радиационной добротности рабочего колебания. Использованная методика определения геометрического профиля рассеивателей пригодна для разрежения спектра ОР произвольных размеров и формы зеркал.
Pendekatan Kognitif dalam Teori Kesehatan Mental Al-Balkhi: Psikologi Positif di Abad Keemasan Islam
Authors: Istikhari Naufil
Published: December 2021

This research is to present a ninth-century Muslim polymath, Abu Zayd Al-Balkhi,and his theoretical contribution on the formation of the epistemological equilibrium betweenmental disorder and mental health which tends to be separated in the history of Westernpsychology. In his phenomenal treatise, The Sustenance of Body and Soul, Al-Balkhi made abridge between ‘positive’ and ‘negative’ psychology in the common clinical approaches. Thisstudy also reveals the cognitive therapy approach as Al-Balkhi’s authentic finding in the Islamicworld, an approach well known long before modern psychology developed. Particular attentionis paid to Al-Balkhi’s emphasizes in positioning his theory of mental health, especially in apositive approach, in such as a pioneer of the Western psychological one.
Hubungan Kelekatan Ayah dan Kontrol Diri dengan Kesejahteraan Subjektif serta Kesejahteraan Psikologis sebagai Mediator pada Mahasiswa
Authors: Filsuf Tasaufi Muhammad Novvaliant , Naimi Anisa Syarifah , Rahmi Nasifah , Jasmine Sabrina Audiht
Published: December 2021

Every individual always faces problems, as well as undergraduate students. The problems are usually related to academic and non-academic issues which require the ability to manage and control themselves, so they are not overwhelmed by these problems. Father attachment can help undergraduate students in overcoming various kinds of problems. This study aims to examine the dynamics of these undergraduate students that focus on the relationship between fatherhood attachment and self-control in which subjective well-being (SWB) and psychological well-being (PWB) mediate among students in Yogyakarta. The subjects of this study were undergraduate students who lived in Yogyakarta (N = 245). This study uses five scales, two scales for the subjective well-being variable, one for the psychological well-being variable, one for the self-control variable and one for the fatherhood attachment variable. The scales used include (a) Satisfaction with Life Scale created by Diener et al (1985); (b) Positive and Negative Affect Scales by Watson et al (1988); (c) Ryff's Psychological Well-Being Scale developed by Ryff (1989); (d) Self-Control Scale from Tangney et al (2004); and (e) The fatherhood attachment scale developed by Armsden & Greenberg (1987). The data were then analyzed using mediation analysis techniques through the JASP application. The results showed that fatherhood attachment did not have a direct effect on self-control, but subjective well-being and psychological well-being could act as mediators of the relationship between fatherhood attachment and self-control.
Uji Validitas Konstruk Work Role Performance pada Karyawan di Indonesia
Authors: Saviera Bella , Susanto Hery , Lestari Kadiyono Anissa
Published: December 2021

Employee performance is critical to the overall success of the company. In achieving their goals, companies will face many challenges. This can be overcome in several ways, one of which is by improving employee performance. Therefore, it is important to measure the role performance of employee in Indonesia. Work role performance scale was first delevoped in Australia in 2007 and have not been adapted for Indonesian population. This study intends to evaluate the validity and the reliability of the Indonesian version of work role performance scale. Aiken’s V formula was used to evaluate the content validity of the scale. Both CTT and Rasch analysis were employed to evaluate the reliability of the scale. Participants in this study were employees, with a total of 370 (n = 370), collected by using accidental sampling techniques. The results showed Aiken’s V of 0.87 to 0.91 shows that items of the adapted scale were relevant to measure the construct. The adapted scale was found reliable with Cronbach’s alpha of 0.936 and Rasch’s person and item reliability were 0.87 and 0.98. In CFA results, the model fit was acceptable (RMSEA=0.08 and CFI=0.96) shows that the data fit the hypoteshized model.
Distres sebagai Mediator antara Resiliensi dan Well-being pada Dewasa di Indonesia
Authors: Nur Shabrina Fariza , Sigumonrong Grace Elizabeth Romorani , Isnandini Nabila , Alya Eka Putri Syora
Published: December 2021

COVID-19 merupakan situasi yang menimbulkan stres, di luar kendali individu, dan berdampak buruk pada well-being. Pada situasi stres, resiliensi dinilai sebagai faktor protektif dari well-being yang ditandai dengan optimisme dan fleksibilitas kognitif. Individu yang resilien dengan kata lain berpotensi memiliki persepsi distres psikologis rendah sehingga memiliki well-being yang baik bahkan selama pandemi COVID-19. Penelitian ini melihat peran distres psikologis sebagai mediator dalam hubungan antara resiliensi dan well-being pada situasi COVID-19 di Indonesia. Pengambilan data dilakukan menggunakan survei online dengan tiga alat ukur berbentuk self-reported inventory yaitu HSCL-10, RS-14, dan MHC-SF. Hasil analisis mediasi dari 260 partisipan menunjukan bahwa distres psikologis berperan sebagai mediator parsial dalam hubungan antara resiliensi dan well-being. Semakin tinggi resiliensi, maka semakin positif individu melihat situasi mereka yang ditandai dengan rendahnya distres psikologis. Distres psikologis yang rendah kemudian berpengaruh terhadap peningkatan well-being. Hasil penelitian ini menguatkan pentingnya peran persepsi kognitif terhadap well-being selama kondisi pandemi COVID-19. Intervensi psikologis dalam bentuk peningkatan fleksibilitas kognitif dan pendekatan mindfulness dapat menjadi alternatif dalam menanggulangi dampak negatif COVID-19 terhadap well-being.
New Techniques in Hemorrhoidal Disease but the Same Old Problem: Anal Stenosis
Authors: Leventoglu Sezai , Mentes Bulent , Balci Bengi , Kebiz Halil Can
Published: December 2021

Anal stenosis, which develops as a result of aggressive excisional hemorrhoidectomy, especially with the stoutly use of advanced technologies (LigaSure, Ultrasonic Dissector, Laser, etc.), has become common, causing significant deterioration in the patient's quality of life. Although non-surgical treatment is effective for mild anal stenosis, surgical reconstruction is unavoidable for moderate to severe anal stenosis that causes distressing, severe anal pain, and inability to defecate. The problem in anal stenosis, unlike anal fissure, is that the skin does not stretch as a result of chronic fibrosis due to surgery. Therefore, the application of lateral internal sphincterotomy does not provide satisfactory results in the treatment of anal stenosis. Surgical treatment methods are based on the use of flaps of different shapes and sizes to reconstruct the anal caliber and flexibility. This article aims to review the functional results, postoperative care, and complications of these methods.
Nativity Status and Poly Tobacco Use among Young Adults in the United States
Authors: Okpala Peace C. , Rosario Carrie , Dupont-Reyes Melissa J. , Martin Romero Michelle Y. , Alam Md Towfiqul , Paivanas Hailey , Echeverria Sandra E.
Published: December 2021

Introduction: Young adults are the second largest segment of the immigrant population in the United States (US). Given recent trends in later age of initiation of tobacco use, we examined variation in use of tobacco products by nativity status for this population group. Methods: Our study included young adults 18-30 years of age sampled in the National Health Interview Survey (2015-2019), a nationally representative sample of the US population. We calculated prevalence of use of any and 2 or more tobacco products (cigarettes, cigars, pipes, e-cigarettes, and smokeless tobacco) for foreign-born (n=3,096) and US-born (n=6,811) young adults. Logistic regression models adjusted for age, sex, race-ethnicity, education, and poverty, while accounting for the complex survey design. Results: Foreign-born young adults were significantly less likely to use any tobacco product (Cigarette = 7.3% vs 10.7%; Cigar= 1.8% vs 4.8%; E-cigarette= 2.3% vs 4.5%, respectively; p<0.01) or poly tobacco use (1.9% vs. 4.2%; p<0.01) than US-born young adults. Adjusted regression models showed lower odds of poly tobacco use among the foreign-born than their US-born counterparts (Odds Ratio = 0.41, (95% Confidence Interval: 0.26-0.63)). Conclusion: Findings highlight the importance of targeted interventions by nativity status and further tobacco prevention efforts needed for the US-born.
Morphology and Performance Characterizations of 316 Stainless Steel Additively Fabricated by Laser Thermal-Joule Heating Composite Process
Authors: Li Suli , Ma Kaijue , Chao Xu , Gao Yang , Yang Laixia , Lu Bingheng
Published: December 2021

The Laser Thermal-Joule Heating Composite Process was studied by orthogonal tests based on an analysis of fabrication parameters such as the laser power, wire feeding speed, and electric current. Temperature profiles and the geometric morphology of deposited layers under different process parameters were analyzed, and the overlaps between the layers and the substrate were observed. Results show that when the temperature at the bottom layer of the additive manufacturing is higher than the melting point of the substrate, and the highest temperature at the top layer does not exceed the over-firing temperature, good morphology and close bonding with the substrate can be obtained. Finally, appropriate process parameters were identified and verified to print multiple layers continuously.
Efektifitas Tanaman Refugia Border Crop terhadap Serangan Hama Plutella xylostella dan Crocidolomia Binotalis pada Tanaman Kubis Bunga
Authors: Witri Ludviyatil , Purnomo Hari
Published: December 2021

Pest attacks that become obstacles in cauliflower cultivation are Plutella xylostella and Crocidolomia binotalis, which can cause yield loss and crop failure. Efforts that can be used to reduce excessive use of pesticides are by controlling by the principles of integrated pest control by manipulating habitat using refugia plants grown as border crops. The plants used as refugia were T. subulata and T. erecta. The purpose of the study was to determine the effectiveness of refugia as a border crop against the intensity and attack of P. xylostella and C. binotalis pests. The design used was a Randomized Block Design (RBD) with four treatments and six replications. Observations were made eight times with an interval of one week. Parameters observed were pest population, attack intensity, and parasitization level. The population of P. xylostella and C. binotalis larvae was highest in the P0 (control) treatment. The lowest average P. xylostella and C. binotalis larvae population was in the P3 treatment (T. subulata + T. erecta). The highest percentage of damage intensity every week in the control treatment (P0). Treatment P3 (T. subulata + T. erecta) gave a significantly different effect compared to treatment P1 (T. subulata) P2 (T. erecta) and P0 (control). No parasitoid was found that attacks P. xylostella, Eriborusargenteopilosus is a parasitoid of C. binotalis with a parasitation rate of 54%.
Formation of a Flow-Line Technical Diesel Engine by the Method of Safety-Free Diagnostics
Authors: Chishkala Pavlo , Meshkov Denis , Bozhko Oduard
Published: December 2021

The analysis of diagnostic methods of diesel engines is given. The principle of diagnostics by certain methods, parameters, by which the diagnostics of fuel injection equipment is conducted, as well as disadvantages of one or another method are considered. The main causes of derangements in the nodes of the fuel injection equipment of diesel engines are determined. The examples have proved that the direct diagnostics methods are the most effective in determining correlation dependencies, for example, indicating the workflow in a diesel cylinder. It is particularly established that the methods of technical diagnostics do not require dismantling of the fuel injection equipment and have proven themselves to be versatile and operative, allowing to comprehensively evaluate the condition of the diesel. The methods of non-separable diagnostic of the condition of a diesel engine are described in detail, the features of such indirect diagnostic methods as vibration, acoustic, indirect indicating by determining the voltage in the cylinder head studs, estimation of the wear rate of component parts with a metal content in engine oil, as well as diagnosing with uneven rate speed of the crankshaft. The vibro-acoustic diagnostic method of a diesel engine can be used to determine the technical condition of such elements as a diesel fuel injection pump , nozzles, and a fuel-priming pump. In addition, the characteristics of motor testers, highly specialized testers and auto scanners are given. A diagnostic feature using a computer auto scanner is that it allows evaluating the condition of nodes in a comprehensive manner, that is, taking into account the mutual influence of derangements on each other. It is noted that the methods that do not require disassembling can be considered the most effective, and the most accurate assessment of the technical condition of the diesel fuel system can be given using the diagnostic method according to the parameters of work processes.
Heat Exchange of the Cylindrical Liquid Body of a Limited Height with the Environment
Authors: Tkachenko Stanislav , Vlasenko Olga , Rezydent Natalia
Published: December 2021

The experimental investigations of the intensity of the heat exchange between the internal surface of the thin-wall metal cylinder and the studied liquid medium were carried out in conditions of its cooling (heating), i.e. under nonstationary heat exchange conditions. The existence of the regular thermal mode in the liquid medium surrounded by the thin-wall metal cylinder has been established. Local in time heat loss coefficients were derived using appropriate dimensionless equations for the stationary mode conditions of heat-exchange in a large volume. Heat loss coefficients were determined using regular thermal mode methods and computational-&-experimental heat loss coefficients. The changes in the relative values of the heat loss coefficients were analyzed using the method of regular thermal mode and computational-&-experimental heat loss coefficients. The deviations in the values of given coefficients in time are mainly within ± 10 %. Relative values of the heat loss coefficients deviate within ± 40 % using appropriate dimensionless equations for the conditions of the stationary mode of heat exchange in a large volume. This conclusion is natural because the cooling (heating) process is nonstationary.
Particularity of Heat Exchange of Twisted Heat Exchangers in External Flow
Authors: Tuz Valerii , Lebed Nataliy , Lytvynenko Maksym
Published: December 2021

Perfecting the existing technologies and developing new ones require to rethink the processes in order to obtain qualitatively new results. Widespread use of cryogenic engineering in the chemical industry and medicine calls for a thorough analysis of both the efficiency of thermodynamic cycles and the hardware design of appropriate equipment. The power necessary to obtain low working medium temperatures is distributed between the cooling of the object and the losses in the various elements of the cryogenic setup. One of the best ways to increase the efficiency of the setup is to use the cold energy recovery. This is done by using various designs of recuperative heat exchangers, such as twisted heat exchangers. Existing methods of calculating the parameters of power equipment are based on empirical dependencies, which require some justification and clarification in order to be used for calculating cryogenic equipment parameters. The article describes the experimental setup, presents the research methods applied and analyses the results of the study on convective heat transfer in external flow past the tubular surface of the twisted heat exchanger. The obtained results for the laminar gas flow mode at Re < 2300 allowed determining the length of the initial heat section depending on the regime parameters of the contact phases and the geometric specifications of the twisted heat exchanger. The obtained dependence will make it possible to refine the method of calculating the parameters of the twisted heat exchanger in the annular channel.
Decreasing NOx Emissions by Way of the Staged Fuel Combustion
Authors: Lohvyniuk Maksym , Novakivskyy Yevhen
Published: December 2021

The purpose of this scientific paper was to analyze the mathematical model built for the staged arrangement of the fuel combustion system and calculate the formation of nitrogen oxides throughout the boiler furnace height for the different distributions of thermal loadings along the full vertical extent of the combustion chamber. The obtained results enable the determination of the overall amount of nitrogen oxides formed in the boiler and it allows us to provide appropriate ecological indices for the boiler when regulating the air concentration in the burner rows. In practice, to suppress the formation of nitrogen oxides we often use such basic methods as low-toxic burners, staged fuel combustion, flue gas recirculation, etc. The analysis of the computations done allows us to draw a conclusion that the operation of the boiler with ecological indices that satisfy standard values of the European Directive 2010/75/EU is only possible for the load below 40 %. After reconstruction of the burner system and adjustment of the air supply system with the observation of above ecological norms the boiler power can be increased up to 80 % using the staged fuel burning with the ensurance of environmental performances during its operation. Computational and experimental data errors varied in the range of 8 % to 12 %. With the increase in the overall chemical incomplete combustion by 40 % to 60 % (q3) these losses are compensated by a decrease in absolute losses due to the boiler aggregate load and the losses through external walls (q5) due to an increase in the boiler power.
Mathematical Modeling of the Working Process of a Two-Stroke Engine with Countermoving Pistons
Authors: Kravchenko Serhii , Linkov Oleg , Shelestov Maxim , Bekaryuk Alexander , Bozhko Eduard
Published: December 2021

Simulation of the working process of an internal combustion engine is the basis for all further calculations and studies of the engine. Of particular relevance is the availability of an adequate mathematical model of the engine process due to the fact that due to the trend of continuous improvement of engine performance, it is necessary to take into account many influencing factors to obtain a satisfactory result. The most complex and dependent on many physicochemical parameters is the process of combustion of fuel in the engine. Models of combustion in diesel engines can be divided into three groups: detailed models; empirical and semipemirical models. The analysis of world experience in research and mathematical modeling of combustion process in internal combustion engines is performed in the work. The advantages and disadvantages of different mathematical models are indicated. It is proposed to use a semi-empirical mathematical model of combustion which describes the differential characteristic of the combustion rate by two curves corresponding to the periods of the first flash and diffusion combustion. Use of such model simplifies performance of calculations and at the same time allows to receive qualitative results considering many factors of influence.
Structural-&-Phase Condition and the Damageability of the Welded Joints of Steam Pipelines at Thermal Power Plants
Authors: Dmitrik Vitaly , Kasyanenko Igor , Krakhmalyov Alexandr
Published: December 2021

The authors studied the interrelation between the type of structure and the damage rate of the welded joints of steam pipelines made of the heat-resistant pearlitic steels that were operated for a long time, i.e. more than 270 thousand hours in the conditions of creepage and low-cycle fatigue. The purpose of this research was to establish the interrelation between the structural-&-phase condition of the metal used for welded joints of the elements of steam systems and their damageability rate for the service life of welded joints exceeding 270 thousand hours. During the studies, the methods of optical and electron microscopy were used according to the requirements of the guideline documentation and also the methods that are used for the determination of mechanical properties. The level of their reliability has been substantiated and the residual life has been determined. To impart functional performances to welded joints we used well-known methods that were appropriately emended according to the structural changes of above joints. Such changes condition the conversion of the original structure of welded joints into the ferrite-carbide mixture. The availability of the conversion process of the initial structure on the thermal action zone sections (TAZ) of welded joints has essential distinctions due to a different disposition of metal to its own damageability. On the whole, the welded joints are damaged more intensively in comparison to the basic metal of steam pipelines. The analysis of the structural state of welded joints in the steam pipelines of thermal power plants as for the extension of their service life results in a considerable economic effect. Understanding the fact that the metal deterioration in welded joints adheres mainly to the fragile mechanism we managed to establish the level of their damageability that demands the renewal of damaged welded joints. We believe that the damageability level of welded joints that tots up to 0.25 or 0.35 of the volume of their TAZ section should be considered as critical for the service life exceeding 270 thousand hours. The damaged welded joints should be renewed throughout the time period of 15 to 20 thousand hours as soon as the specified damageability level is attained.
SENSITIVITY OF STRENGTH, RIGID AND DYNAMIC CHARACTERISTICS OF THE CONSOLE ROTOR TO VARIATION OF DESIGN PARAMETERS
Authors: Tkachuk Mykola А. , Grabovskiy Andrey , Prokopenko Nickolay , Tkachuk Mykola M. , Shut Oleksandr , Lipeiko Andrii , Litvin Boris , Ovcharov Egor , Mosnitska Daria
Published: December 2021

The analysis sensitivity of strength, rigid and dynamic characteristics of the console rotor to variation of design parameters in paper describes The speed of rotation of the shaft, the material of the impeller vary. The dependences of radial and axial displacements on the angular velocities of rotation and the modulus of elasticity of the impeller material are established. For objects of the type of rotary systems with a cantilever arrangement of the impeller, not one, but a set of criteria has been introduced into consideration, which should be taken into account in the research of this type of objects. The tendencies of change of the first and second critical rotational speeds from the modulus of elasticity, rotor rotational frequencies and density of the impeller material are also determined. On this basis, recommendations have been developed for determining the design parameters of the rotor part of the air blower with a cantilevered impeller.
Keywords: air blower; critical rotation speed; natural vibration frequency; rotary system; stress-strain state
NUMERCNAL ANALYSIS OF CONTACT INTERACTION OF BODIES WITH NEARLY FORM SURFACES
Authors: Grabovskiy Andrey , Tkachuk Mykola А. , Domina Natalia , Tkachuk Ganna , Ishchenko Olha , Tkachuk Mykola M. , Kalinin Pavel , Voloshina Iryna , Tretyak Vladeslav , Saverska Mariia , Kutsenko Serhii , Loznyi Oleg
Published: December 2021

Contact interaction of structural elements has been studied in the case of nominally close (nearly matching) surfaces. A non uniform gap is present between the contacting parts. Contact pressure and contact spot depend on the shape of this gap. Correspondingly so does the stress-strain state of the contacting bodies too. Since the problem is essentially nonlinear, the contact pressure distribution and the contact zones change with the growing loads. The solution is qualitatively different to the case of perfectly matching bodies. For the latter case, the contact pressure is linearly proportional to the load and the contact zone is predefined. Hence for the real structures for which the deviation from the nominal shape is unavoidable the impact of these inaccuracies on the contact pressure distribution and the stress-strain state need to be taken into account. This problem is addressed in the paper by example of elements of stamping dies.
Keywords: element of stamping dies, stress-strain state, contact pressure, contact interaction, variational inequalities, Kalker’s variational principle, finite element method, boundary element method
ADVANTAGES AND DISADVANTAGES OF DIFFERENT METHODS FOR STUDYING THE PHASE-STRUCTURAL STATES OF MATERIALS (A REVIEW)
Authors: Kniazieva (Postelnyk) Hanna , Kniaziev Serhii , Tkachuk Mykola M. , Pinchuk Natalia
Published: December 2021

The paper provides a brief overview of the standard capabilities of X-ray techniques for studying materials with examples of modern performance of elemental and structural studies. X-ray research methods make it possible to reveal the elemental and phase-structural state. Thanks to modern software and electronic databases, the use of previously complex techniques is becoming simpler and more accessible. To illustrate the solution of specific problems, several examples of obtaining and decoding diffraction patterns and identifying the phase composition of the coating and ceramic material are given. An example of work in modern specialized software for acceleration and automation of phase identification is shown. For clarity, an example of identifying phases using electronic database cards is presented, which is still used today for manual decoding.  The practice of interaction between researchers shows that even specialists in the field of X-ray structural analysis are not always aware of modern methods of processing and decoding the obtained data. The possibilities and algorithm of action in research can be interesting for students, engineers, researchers of materials science and mechanical engineering profile.

Keywords: microscopy, X-raystructural analysis, X-rayfluorescence analysis
TECHNOLOGY OF INFORMATION COMPUTER SYSTEMS IN APPLICATIONS AND TASKS
Authors: Ol'hovs'ka Victoriia
Published: December 2021

Розглянуто можливості застосування технології інформаційних комп’ютерних систем у різновидах прикладів та задач навчання студентів. Проведено та проаналізовано: бізнес-процеси обраної предметної області, визначення бізнес-функцій та бізнес-процесів, постановка задачі. Розроблені вимоги до інформаційної системи, та визначення функціональних вимог до інформаційної системи. Визначені критерії логічного та фізичного моделювання баз даних; розроблено UML моделювання клієнтської частини  інформаційної системи. Проведена розробка вимог до функцій серверної частини та інтерфейсу клієнтської частини інформаційної системи, описані можливості проектних рішень, розроблено інтерфейс клієнтської частини системи, створено базу даних для обраної платформи; розроблені засоби збереження процедур, функції для серверної частини інформаційної системи (ІС) та інтерфейс клієнтської частини ІС. Описане математичне обґрунтування застосованого алгоритму та зроблені необхідні висновки.
RESEARCH OF GENERAL HYDROGEN TECHNOLOGY ACCORDING TO OPTIMAL PARAMETERS AS A COMPONENT OF COMPLEX DEVELOPMENT OF EFCE AND CFE-UA ASSOCIATIONS
Authors: Zipunnikov Mykola , Bukhkalo Svetlana
Published: December 2021

The analysis of the prospects for the development of hydrogen energy in the EU and Ukraine is carried out. The possibilities of implementing projects and technologies for the production of green hydrogen for industrial use are considered. The conditions for the implementation of the project for the creation of a research and development center for hydrogen and hydrogen fuel cell technology are presented. A review of publications devoted to the process of obtaining hydrogen from water has been completed. The main factors influencing the course of reactions in the production of hydrogen from water using alloys are considered. Recommended alloys for producing hydrogen at autonomous facilities. The components of the research algorithm are given taking into account the system of process factors based on the analysis of literature data on the technology of hydrogen production by the electrolysis of water. The general principles of calculating gas generators have been established, which should be based on the basic principles of the thermodynamics of heterogeneous processes: classical thermodynamics of multiphase and heterogeneous systems.
Study of the structure of gas flow іn a cyclone wіth іntermedіate dust removal
Authors: Maistruk Volodymyr
Published: December 2021

The works in which designs of the dust collectors, which are often used in the industry, are analyzed. It is shown that the efficiency of dust collectors largely depends on the structure of the gas flow in the apparatus. Based on the analysis of the current cyclone devices, a picture of the separation process is obtained, and the factors that negatively affect the operation of dust collectors are identified. It is established that forecasting the work of dust collecting devices in certain conditions is most effective to perform methods of numerical modeling and simulation of the separation process, which are widely used for the research of devices of this type. Using the methods of numerical simulation, the study of the cyclone with intermediate dust removal was carried out. In this cyclone, the change in the radius of the apparatus of the tangential, radial, and axial velocity components is investigated. In the course of the research, it is established that in the separation space the tangential component of velocity increases from 18–20 m/s in the upper part of the device to 22–25 m/s in the area of the lower end of the exhaust pipe, the radial component of velocity takes values from 0 to 2 m/s, and the axial component of the speed has a maximum value of 10–15 m/s. In the conical part of the apparatus the tangential component of velocity decreases from 27 m/s in the upper planes of the conical part of the apparatus to 10 m / s near the dust unloading pipe, the radial component of speed has centripetal character, the axial component of speed decreases as the gas flow to the dust unloading pipe decreases. It has been established that in the cylindrical part of the apparatus about 60 % of the gas flow volume is transferred from the downstream to the upstream by a secondary vortex, and in the conical part, about 40 % of the gas volume is transferred from the downstream to the upstream. It is shown that large values of the tangential component of velocity in the separation zone contribute to the ingress of dust particles into the annular space behind the dust unloading holes, and small values of the tangential component of velocity, axial and radial in the annular space behind the dust unloading holes has a positive effect on the operation of the dust collector.
Resistive properties of Janson’s point contacts in the conditions of polarization inversion
Authors: Pospelov Alexander , Kamarchuk Gennadii , Sakhnenko Mykola , Savitskii Andrii , Proskurina Valeriya , Zyubanova Svitlana
Published: December 2021

The sensitive element of a new quantum sensor generation is the Janson dendritic point contact. Analytes that are in the space surrounding the sensitive element are able to interact with the freshly formed surface of the conduction channel of the Janson quantum point contact, as well as with the surface of the dendrite during its growth. This interaction provides the influence of the substances under study on the configuration of the output characteristic of the sensor, represented by the system conductivity histogram. The conductivity histogram is built on the basis of the chrono-resistogram of the self-oscillating point-contact cyclic switchover effect, which is directly recorded under self-oscillation conditions. In the structure of the sensor element, Janson's dendritic point contact is immersed in an electrolyte and in an electric field forms a chrono-resistogram, which depends on the environment composition. The paper considers one of the aspects of such chrono-resistograms formation. The features of a gapless electrochemical system in the process of realizing the point-contact cyclic switchover effect are analyzed. Modeling the sensitive element in the form of a gapless electrode system allowed explaining the mechanism and dynamics of the transition “Janson point contact – dendrite and counter electrode in the electrolyte”. The most important parameter of the gapless electrode system is the coordinate of the polarization inversion boundary. It is shown that the idea of the coordinate of the polarization inversion boundary plays a fundamental role in modeling the resistive properties of a point-contact system and its lifetime. The synthesized mathematical models describe well the experimentally obtained dependences of the resistance on the exposure time of the nanostructure in an electric field. It was found that the dependence of the contact resistance on the exposure time, obtained under the assumption of a linear distribution of the anodic polarization along the main axis of the conduction channel, is described by a differential equation in which the growth rate of resistance is directly proportional to the cube of this resistance. The materials obtained make it possible to purposefully optimize the design parameters and operating conditions of sensor devices based on Janson point contacts for the analysis of complex gaseous and liquid mixtures.