bluuebunny/crossref_metadata_2025 huggingface dataset:
Kartografija u Hrvatskoj 2019–2023, Nacionalni izvještaj na 19. generalnoj skupštini ICA-e
Authors: Lapaine Miljenko
Published: February 2024

Hrvatska je članica Međunarodnoga kartografskog društva (International Cartographic Association − ICA) od 1995. godine, a jedna od njezinih obveza je podnošenje nacionalnih izvještaja o kartografskim aktivnostima generalnoj skupštini koja se održava svake četiri godine. Nositelj tih aktivnosti u Hrvatskoj je Hrvatsko kartografsko društvo.
The mediating effect of cultural diversity on organizational commitment and well-being of Filipino cruise seafarers
Authors: Calinao Ryan  Joseph G , Alvarez Lyziel , Calderon Joshua , Eusebio Karl
Published: February 2024

Purpose The purpose of this study is to identify how the current setting of the workplace environment onboard, specifically hotel operations, affects the level of commitment and overall well-being of Filipino cruise seafarers towards their workmates of different nationalities. Design/methodology/approach This study focuses on Filipino cruise seafarers’ experiences in working in a cross-cultural environment onboard. Researchers used quantitative-predictive-causal research for this study. Using the adapted and modified instrument, researchers surveyed 291 Filipino cruise seafarers working in hotel operations through online data collection procedures. Findings The results revealed that cruise seafarers agree that cultural diversity, organizational commitment, and well-being are essential in seafarers’ living and working conditions onboard. Regarding psychographic profiles in terms of lifestyle, the study reveals a significant difference in cultural diversity and organizational commitment. Using the Pearson Correlation, the study found a high relationship between the level of organizational commitment and well-being. As the level of organizational commitment increases, the level of well-being of respondents also tends to increase. By using SB-SEM through AMOS, it revealed that cultural diversity mediates the relationship between organizational commitment and well-being. The study only covers Filipino cruise seafarers' work and life experiences in hotel operations. The sample for this study was restricted to the other types of maritime groups. In addition, this study is strictly limited to Filipinos as the primary population for this research. Keywords: Filipino cruise seafarers, cultural diversity, organizational commitment, well-being, structural equation modeling
Hybrid Crow Search and RBFNN: A Novel Approach to Medical Data Classification
Authors: Ali Marai , Khan Faisal , Atta Muhammad Nouman , Khan Abdullah , Khan Asfandyar
Published: February 2024

The Radial Basis Function Neural Network (RBFNN) is frequently employed in artificial neural networks for diverse classification tasks, yet it encounters certain limitations, including issues related to network latency and local minima. To tackle these challenges, researchers have explored various algorithms to enhance learning performance and alleviate local minima problems. This study introduces a novel approach that integrates the Crow Search Algorithm (CSA) with RBFNN to augment the learning process and address the local minima issue associated with RBFNN. The study evaluates the performance of this innovative model by comparing it to state-of-the-art models like Flower-pollination-RBNN (FP-NN), Artificial Neural Network (ANN), and the conventional RBFNN. To assess the efficacy of the proposed model, the study employs specific datasets, such as the Breast Cancer and Thyroid Disease datasets from the UCI Machine Repository. The simulation results illustrate that the proposed model surpasses other models in terms of accuracy, exhibiting lower Mean Squared Error (MSE) and Mean Absolute Error (MAE) values. Specifically, for the Breast Cancer dataset, the proposed model attains an accuracy of 99.9693%, MSE of 0.000307024, and MAE of 0.00789449. Likewise, for the Thyroid Disease dataset, the proposed model achieves an accuracy of 99.9535%, along with MSE of 0.000464932 and MAE of 0.0057098. For the diabetes dataset, the proposed model demonstrates an accuracy of 98.8073%, MSE of 0.003024, and MAE of 0.009449. In summary, this analysis underscores the enhanced accuracy and effectiveness of the proposed model when compared to traditional approaches.
Modelling of Virtual Campus Tour in Minecraft
Authors: Tan Lin Liyana , Neo Han-Foon
Published: February 2024

Virtual tours have revolutionized the way to explore and experience places from the comfort of our own home. Through advanced technology and immersive digital platforms, virtual tours offer a compelling alternative to tradition face-to-face visits. Whether a famous landmark, museum, real estate or natural wonders, virtual tours offer a unique opportunity to navigate and discover these places form a distance. Meanwhile, creating a virtual tour in Minecraft can provide a unique and immersive experience that sets the users apart from other virtual tour platforms. Minecraft is one of the most popular video games in the world and boasts a large and dedicated community of players. Using Minecraft for a virtual tour allow users to reach a larger audience who are already familiar with the game, increasing the likelihood of engagement and participation. In this paper, the aim is to create a virtual campus tour in Minecraft to give the visitors an immersive and interactive experience with creative freedom. A series of buildings have been built such as Siti Hasmah Digital Library, Common Lecture Complex (CLC) and Smart Lab. Visitors can move around the campus with some gameplay mechanics using mouse and keyboard. Building information was also integrated so visitors can see details about each building during the virtual tour. The virtual tour provides access, comfort and a sense of connection to prospective students, their families and international visitors. Additionally, it serves as a low-cost marketing tool that increases engagement, attracts potential students, researchers and staff and ultimately benefits the University’s recruitment efforts.
A Lung Cancer Detection with Pre-Trained CNN Models
Authors: Chai Chee Chiet , Khoh Wee How , Pang Ying Han , Yap Hui Yen
Published: February 2024

Lung cancer is a common cancer in Malaysia, affecting the majority of male citizens. The early detection of lung cancer will decrease its death rate. The only way to detect lung cancer is with a CT scan, and it also requires the doctor to check the scan to confirm the disease. In another way, the computer's support for the detection and diagnosis tool will assist doctors in determining lung cancer more accurately and efficiently. There are three main objectives for this research work. The first target is to study state-of-the-art research work to detect and recognize lung cancer from CT scan images. Then, the article will aim to adopt pre-trained convolutional neural network models in lung cancer detection. It also evaluates the performance of convolutional models on lung cancer imagery data. Then, the pre-trained models with a few added layers and modifications to parameters such as epochs, batch size, optimizer, etc. to conduct model training in this article. After that, Python Pylidc is used in image pre-processing to filter the dataset. Overall, pre-trained models such as ResNet-50, VGG-16, Xception, and MobileNet achieve above-state-of-the-art performance in classifying lung cancer from CT scan images in the range of 78% to 86% accuracy. The best detection accuracy result is the pre-trained VGG-16 model with the addition of some fully connected layers, 16 batch sizes, and the Adam optimizer, which achieved 86.71%.
Optimizing Medical IoT Disaster Management with Data Compression
Authors: Mrewa Nunudzai , Mohd Ramly Athirah , Amphawan Angela , Neo Tse Kian
Published: February 2024

In today's technological landscape, the convergence of the Internet of Things (IoT) with various industries showcases the march of progress. This coming together involves combining diverse data streams from different sources and transmitting processed data in real-time. This empowers stakeholders to make quick and informed decisions, especially in areas like smart cities, healthcare, and industrial automation, where efficiency gains are evident. However, with this convergence comes a challenge – the large amount of data generated by IoT devices. This data overload makes processing and transmitting information efficiently a significant hurdle, potentially undermining the benefits of this union. To tackle this issue, we introduce "Beyond Orion," a novel lossless compression method designed to optimize data compression in IoT systems. The algorithm employs advanced techniques such as Lempel Ziv-Welch and Huffman encoding, while also integrating strategies like pipelining, parallelism, and serialization for greater efficiency and lower resource usage. Through rigorous experimentation, we demonstrate the effectiveness of Beyond Orion. The results show impressive data reduction, with up to 99% across various datasets, and compression factors as high as 7694.13. Comparative tests highlight the algorithm's prowess, achieving savings of 72% and compression factor of 3.53. These findings have significant implications. They promise improved data handling, more effective decision-making, and optimized resource allocation across a range of IoT applications. By addressing the challenge of data volume, Beyond Orion emerges as a significant advancement in IoT data management, marking a substantial step towards realizing the full potential of IoT technology.
Francesconi, Federica. Invisible Enlighteners: The Jewish Merchants of Modena, from the Renaissance to the Emancipation. Philadelphia: University of Pennsylvania Press, 2021.
Authors: Devine Luke
Published: February 2024

Book Review
Jewish Mysticism as a Form of Feminism in Early 20th Century Hungarian Jewish Literature: Anna Lesznai’s Response to Otto Weininger
Authors: Rethelyi Mari
Published: February 2024

This article examines Anna Lesznai’s radical imagining of sex and its use for transcendental purposes that heavily rely on Jewish mystical ideas intertwined with Otto Weininger's theory of gender binarism. In her gender theory—part of feminist discourse at the turn of the twentieth century—Lesznai describes female love, using religious language and ideas from Jewish mysticism, especially those resembling Hassidic concepts, and ultimately compares sexual union to yihud- unio mystica with God. Working within the patriarchal understanding of the biological definition of gender and of the concept of "female difference," Lesznai’s feminism rooted in the belief that certain personality traits and skills are inherently gendered, but she reverses the hierarchy by placing women in the position of power, thus turning Jewish mysticism and Weininger’s gender philosophy on its head.
PERIODIZATION OF FRENCH BORROWINGS IN THE BASIC ENGLISH VOCABULARY
Authors:   Mykhailo Tuhan-Baranovskyi Donetsk National University of Economics and Trade, Vorobiova L. V. , Dehtiar Ya. V. ,   Mykhailo Tuhan-Baranovskyi Donetsk National University of Economics and Trade
Published: February 2024

Objective. The objective of the article is to analyze and compare French borrowings which came into the English language; to identify periodization, some of its stages and periods, to analyze and compare the French borrowings appropriate to each period in order to enable effective intercultural research process connected with historical aspect of philological and linguistic studies. Methods. The main scientific results are obtained using the method of theoretical generalization, which made it possible to determine and nature of French borrowings’ periodization; comparative – to compare historical phenomena, events and facts of the socio-cultural life of the studied countries; the problem-genetic method – to justify the provisions regarding the analysis of problems that may hinder effective intercultural research process connected with historical aspect of philological and linguistic studies. Results. The theoretical analysis of the nature of the French borrowings made it possible to identify the stages and periods of possible periodization that enables effective intercultural studies in the fields of linguistics, philology, terminology. Interpretation and analysis of the genesis of possible periods will lead to successful management of the educational process for philology and history students. Three periods are identified. The first period is characterized with the Norman French borrowings in such semantic groups as: administration, titles and ranks of nobility, jurisdiction, the сhurch and religion, military terms. The second period is characterized with the Parisian French borrowings in such semantic groups as: entertainment, fashion, cuisine. On probation, the third period can be characterized bilingually where the French borrowings can be traced in such semantic groups as: art, architecture, literature, science, medicine.
CREATIVE TECHNOLOGIES APPLICATION IN THE PROCESS OF TEACHING A FOREIGN LANGUAGE
Authors:   Mykhailo Tuhan-Baranovskyi Donetsk National University of Economics and Trad, Rybalka N. V.
Published: February 2024

Objective. The objective of the article is to consider and analyze creative pedagogical technologies for the developing foreign language communicative competence; identifying their main characteristics; familiarization with heuristic learning technologies and their classifications; consideration of examples of the use of language and group creative games as methods of creative writing and heuristic methods in the process of learning a foreign language. Methods. The main scientific results are obtained using such research methods as analysis of psychological and pedagogical literature, generalization of best practices and observation. Results. Based on the fact that creative technologies for teaching a foreign language will contribute to the development of students' creative thinking and their linguistic creativity, and will ensure a high level of foreign language communicative competence, the author comes to the conclusion that the development of students' linguistic creativity can be carried out on the basis of creative writing technologies, which will contribute to the removal of psychological barriers and will stimulate students' creative thinking when completing written tasks. Heuristic learning technologies have a huge potential for the development of creativity, the main characteristics of which are: openness, problematic, lack of a known solution in advance and reliance on the student's creative potential. The technologies of heuristic foreign language learning for future specialists include heuristic methods of learning an object, identifying its main features, and heuristic methods of transforming the features of an object and creating a new object. The presented heuristic techniques can be used in foreign language classes in different versions depending on the type of communication skills that the class is aimed at developing.
INFLUENCE OF EXTERNAL FACTORS ON LANGUAGE CHANGES
Authors:   Mykhailo Tuhan-Baranovskyi Donetsk National University of Economics and Trade, Revutska S. K. , Bilokon V. M. ,   Mykhailo Tuhan-Baranovskyi Donetsk National University of Economics and Trade
Published: February 2024

Objective of the article is to find out the main external and internal factors influencing language changes, in particular in the Ukrainian language. Methods. The main scientific results are obtained through an analytical review of the theoretical positions of domestic scientists, in which the issue of internal and external influences on the development and functioning of the Ukrainian language is considered; observation of language phenomena in the modern Ukrainian language. Results. The influence of external factors on language changes is one of the key topics in the field of linguistics. Language, as a living organism, constantly develops and undergoes changes under the influence of various external and internal factors. The study of these factors is currently relevant in connection with the strengthening of the struggle for the purity of the Ukrainian language and its purification from the influences on the lexical composition of the imperial aggressor country The influence of external factors on language changes is a necessary and natural process that occurs in the modern world. Similar processes lead to activation of internal influences. Cultural contact, socio-political changes, technological progress and other factors contribute to the evolution of language through borrowing, adaptation and transformation of the vocabulary and the language system in general. Over the past couple of decades, we have had an impact on vocabulary in various areas, including education. The distance learning system and the globalization of the information space affect the spread of foreign terms and expressions, especially from English to Ukrainian. This is reflected in the use of foreign words, names of educational platforms, abbreviations, logos and terms in communication processes. Changes in language reflect modern realities and needs of society, contribute to more accurate expression of thoughts and ideas. However, it is important to maintain a balance between enriching the language with new borrowings and preserving national identity and cultural heritage.
TRANSLATION TRANSFORMATIONS IN THE PROCESS OF FICTION TEXTS TRANSLATION
Authors:   Mykhailo Tuhan-Baranovskyi Donetsk National University of Economics and Trade, Udovichenko H. M. , Demchenko V. L. ,   Mykhailo Tuhan-Baranovskyi Donetsk National University of Economics and Trade
Published: February 2024

Objective of the article is to justify that the translation of the text can be artistically adequate only if it is considered as a two-level monolith with the obligatory selection of a code-schematic layout and its decomposition on the lines of the author's perspective on a micro-theme, theme, macro- theme and hyper-theme. Methods. The main scientific results are obtained applying a set of general scientific and special methods of research, namely: analysis and generalization of scientific literature on the problems of comparison in linguistics; theoretical generalization, analysis and synthesis; holistic and integral approaches to the study of comparison in linguistics; comparative, descriptive and analytical methods. Results. The doctrine notes that literary translation is a translation of works of fiction, and the main goal of a work of this type is to achieve an aesthetic impact, to create an artistic image; such an aesthetic orientation distinguishes artistic speech from other acts of speech communication. We cannot but agree with their opinions that the space of literary translation is insatiable, it absorbs all world literature with its hidden meanings, sifting through the cells of translations from language to language unstoppable, at first glance, time. Currently, there are many works on translation studies devoted to translation transformations, the problems of which occupy a central place in the theory of translation, and knowledge of its theoretical foundations is extremely important in the work of any translator. Giving definitions to translation transformations, philologists write that in fact we are talking about the relationship between the initial and final language expressions, about the replacement in the process of translation of one form of expression by another, about the replacement, which we figuratively call transformation. Referring to the works of other researchers, they note that translation transformation is such a process of translation, during which the system of meanings contained in the speech forms of the source text, perceived and understood by the translator due to his competence, is naturally transformed due to interlingual asymmetry into a more or less similar system of meanings, clothed in the form of the target language. The issues of typology and functionality of translation transformations are currently debatable.
Pelatihan Pembuatan Animasi Sederhana Menggunakan Macromedia Flash Untuk Meningkatkan Keterampilan Siswa SMK Karya Utama Tanjungbalai
Authors: Andriyani Suci , Efendi Zulfan , Latiffani Chitra
Published: February 2024

Abstract: Education plays an important role in quality human civilization to increase human resources globally. This development reflects the close relationship between education, technological innovation and the advancement of knowledge as an integral part of society's social and intellectual evolution. The use of technology-based media is considered to provide significant benefits for both teachers and students in the process of teaching and learning activities. In this context, the education system in vocational schools should explore the potential resources or potential available around the school environment, which are relevant to the demands of the world of work. In an effort to prepare student graduates who are superior and ready to work and are able to compete in the job market, there needs to be preparation in improving the hard skills and soft skills of mature students. This service activity aims to provide assistance and training to Karya Utama Vocational School students through the use of Multimedia Technology as additional skills. The method in this activity applies training and observation to students. As a result of this activity, 85% of students were able to create simple animations using Macromedia Flash software. Keywords: animation; macromedia flash; multimedia; training.
Pemberdayaan Kelompok Tani Unggas Jaya Melalui Teknologi Monitoring Gas Amonia Dan Suhu Kandang Otomatis Berbasis IoT
Authors: Risald Risald , Baso Budiman , Ullu Hevi Herlina , Lisnahan Charles Venirius
Published: February 2024

The Poultry Jaya farmer group is in the city of Kefamenanu, the native chicken farming system of the Jaya Poultry Group is still conventional. One of the main problems faced by this group is the lack of monitoring and controlling the temperature of the cage as well as monitoring the ammonia gas produced by chicken droppings. Temperature and ammonia gas levels have a major impact on chicken growth and health. To overcome this problem, it is necessary to implement Internet of Things (IoT) technology integrated with Android applications. This technology allows automatic and periodic monitoring of cage temperature and ammonia gas levels. Farmers can access information via the Android app and take necessary action if significant changes occur. This community service aims to build tools and systems for automatic temperature control and IoT-based ammonia levels integrated with Android, as well as introducing technology and providing training and assistance to the Unggas Jaya farmer group regarding IoT technology in chicken coop management. With the existence of IoT technology, it is hoped that the behavior patterns of farmers will change to become more modern and efficient. This technology can help improve poultry farming performance, reduce risks, and provide convenience in cage management so that it will bring positive changes to the productivity and welfare of farmers. Keywords: Poultry Jaya farmer group; chicken coop; Internet of Things (IoT)
Acquired Nonaccommodative Esotropia in Older Children
Authors: Kim Inkee , Kang Nam Yeo
Published: February 2024

Purpose: To evaluate the clinical findings and surgical outcomes in older children with acquired nonaccommodative esotropia (ANAET).Methods: A retrospective review was conducted on the medical records of 9 patients (aged 9-17 years) who were diagnosed with ANAET between 2014 and 2021. The age of onset, angle of deviation, presence of symptomatic diplopia, fusional state, stereo-acuity, and surgical results were analyzed.Results: The mean age at onset was 12.0 ± 2.8 years, and the mean duration of esodeviation was 11.8 ± 14.4 months. The mean follow-up period was 32.0 ± 19.5 months. Five of 9 patients presented with symptomatic diplopia accompanying esotropia, and two complained diplopia only. The mean angles of deviation were 32.0 ± 11.5 prism diopters (PD) for near and 31.8 ± 12.4 PD for distance. Six patients showed progressive esotropia, and none had neurological or intracranial disorders. Surgical correction was performed at 17.1 ± 15.0 months after the onset. At the final follow-up, all patients resolved diplopia, and 88.9% achieved successful motor alignment. Improved stereopsis was observed in all patients, with 77.8% demonstrating fusion at both near and far distant. However, only 44.4% gained normal 60 arcsec stereopsis.Conclusions: Diplopia with estropia was the main presenting symptom of ANAET in older children. Surgical treatment was effective in achieving good postoperative motor alignment and fusion, but recovery of fine steropsis was limited.
A Theocratic Approach To Governance In Ancient Times: Assyrıans
Authors: Pekşen Okay , Topaloğlu Yasin
Published: February 2024

The organized belief systems, temple structures, and religion-state relations that emerged with the Sumerians in ancient Mesopotamia began to undergo Semiticization with the dominance of Semitic societies in the region. Sumerian cultural elements, which underwent Semiticization during the Old Babylonian period, assumed an Assyrian character with the rise of the Assyrian State in the Ancient Near East and its evolution into an imperial structure. The Assyrian society, known for its religious orientation, operated on a religion-based understanding of state organization and the formulation of state policies. It was believed that divine requests and orders influenced various situations, such as kings' legitimacy, heirs' determination, and decisions regarding wars and peace. The land was perceived as belonging to the gods, and the kings were seen as representatives of the gods on earth. This study aims to uncover the theocratic aspects of Assyrian state administration based on information gleaned from cuneiform sources and modern literature.
Safety and Effectiveness Assessment of Ultraviolet-C Disinfection in Aircraft Cabins
Authors: Belland Kris , Garcia Diego , DeJohn Charles , Allen Gary R. , Mills William D. , Glaudel Stephen P.
Published: February 2024

INTRODUCTION: Aircraft cabins, susceptible to disease transmission, require effective strategies to minimize the spread of airborne diseases. This paper reviews the James Reason Swiss Cheese Theory in mitigating these risks, as implemented by the International Civil Aviation
Organization during the COVID-19 pandemic. It also evaluates the use of airborne ultraviolet-C (UV-C) light as an additional protective measure.METHODS: Our approach involved a thorough literature review by experts and a detailed risk-vs.-benefit analysis. The review covered existing
research to understand the scientific foundation, while the analysis used established techniques to assess the impact of influenza and COVID-19 in terms of infections, deaths, and economic costs.RESULTS: Integrating UV-C light in aircraft cabins, when applied with appropriate scientific
understanding and engineering safeguards, has the potential to reduce in-flight disease transmission. This additional mitigation strategy can work synergistically with existing measures.DISCUSSION: The research and risk-vs.-benefit analysis present strong evidence for the safety
and effectiveness of continuous UV-C disinfection in aircraft cabins. It suggests that UV-C light, maintained below exposure limits, can be a valuable addition to existing measures against disease transmission during flights.Belland K, Garcia D, DeJohn C, Allen GR, Mills WD, Glaudel
SP. Safety and effectiveness assessment of ultraviolet-C disinfection in aircraft cabins. Aerosp Med Hum Perform. 2024; 95(3):147–157.
Subalpine Meadow Vegetation of Talish Highlands of Azerbaijan
Authors: Aslanova S.
Published: February 2024

Subalpine meadow vegetation of Talish highlands has been spread over the subalpine zone of Lankaran highlands at lawny mountain-meadow soils at the height of 1800 m to 2500 m above sea level. During the carried out ecological-geobotanical research, it has been determined 7 formation classes, 12 formation groups and 20 associations. In parallel with the study of type composition and structure of phytocenosis found in the area of investigation, it has been also determined endemic species, productivity of formations, and intensification of degradation at soil-plant coverage of some lawny subalpine meadows, decrease in abundance and productivity of forage crop. Currently, for the purpose of the improvement of natural phytocenosis productivity, crop quality, protection of their genetic reserve and landscapes, as well as the vegetation study for solution of protection problems on the base of scientific means is of a great importance.
Methods for the Determination of Fire Blight on Pome Fruit Crop Plants in the Western Part of Azerbaijan
Authors: Guliyeva Z.
Published: February 2024

Fire blight caused by Erwinia amylovora (Burrill, 1882) Winslow et al., 1920 causes significant production losses in the world’s leading pome fruit crop producing countries. The main route of infection of many fruit crops, including apple and pear trees, is through newly blooming flowers. The bacterium overwinters in the bark tissue along the edges of cankers formed on branches and stems as a result of infection in the previous year and becomes a source of infection in the next year. Determining the prevalence of the disease in areas with a large number of orchards is important from the point of view of disease control. Therefore, the purpose of the work is to study the prevalence of the disease in the Ganja-Dashkesan and Gazakh-Tovuz Economic Regions, as well as the accurate diagnosis of the obtained E. amylovora isolates using classical and molecular methods. For this purpose, trees in the studied apple and pear orchards were examined for the disease, the pathogen was isolated from infected plants, and morphological, biochemical, physiological and molecular analyzes were carried out. Among 36 bacterial isolates obtained from 27 samples of infected plants, Erwinia amylovora was identified in 11 as a result of morphological, biochemical, physiological and molecular tests.
Blade excitation related flow behavior analysis on the turbocharger’s centrifugal compressor with volute and casing treatment
Authors:   Institute for aero engine Tsinghua University, Zheng Xuedong , Yan Chuanxiang ,   Institute for aero engine Tsinghua University, Wang Baotong ,   Institute for aero engine Tsinghua University, Zheng Xinqian ,   State Key Lab of Automotive Safety & Energy Tsinghua University
Published: February 2024

High cycle fatigue due to unsteady aerodynamic excitation is a common failure mode of turbocharger blades. This paper numerically investigates the flow unsteady characteristic in a turbocharger compressor with asymmetric volute and SRCT(Self-recirculation-Casing-Treatment). Unsteady-Reynolds-Averaged-Navier-Stokes (URANS) computation is performed on the full-annulus compressor model. The data-driven method of Dynamic Mode Decomposition (DMD) is used to explore the unsteady flow behavior related to blade excitation, also the result is compared with Fourier Decomposition (FD) method. It is concluded that asymmetric volute is a strong excitation source, which forms the 1Nodal Diameter(ND) and 2ND pressure pattern. As the operating condition changes from choke side to near-stall side with back pressure increasing, 1ND morphs into 2ND. The SRCT is a complex excitation source that contains two dominant phenomena caused by the potential field and the interaction between injection flow and the mainstream of the blades. The SRCT should be carefully designed to alleviate the injecting flow non-uniformity caused by the strut. As for the comparison of DMD and FD, the result from DMD is very similar to that from FD in the analysis of periodic unsteady flow characteristics, and both of them can reveal the blade excitation source to support the further blade design.
A rapid method for turbomachinery aerodynamic design and optimization using active subspace
Authors:   Nanjing University of Aeronautics and Astronautics, Xu Jiasen , Lou* Fangyuan ,   Institute for Aero Engine Tsinghua University
Published: February 2024

Preliminary design is a crucial step in the turbomachinery aerodynamic design process, which involves the initial conceptualization and serves as the foundation for subsequent detailed design and analysis. During preliminary design, designers typically use a combination of empirical correlations, simplified flow models, and computational tools to evaluate the impact of different design parameters on the machine's performance. This iterative process heavily relies on the designer's experience and knowledge, and errors made during preliminary design may not be rectifiable in later design phases. To address this challenge, this paper proposes a novel optimization strategy for turbomachinery aerodynamic preliminary design using active subspace. The method utilizes active subspace techniques to reduce the dimensionality of the design space, making efficient and accurate exploration of the space possible. In addition, the open-access Multall turbomachinery design suite is employed to evaluate the aero-thermal performance of different designs. The method was then utilized to optimize the aerodynamic design of the blade profile for a ducted fan. Results show that the optimization strategy can identify the most significant directions in the design space, providing designers with a clear path to achieving an optimal design. Overall, the proposed method can be of good value to the turbomachinery design community attribute to its reduced dependence on the designer's experience and elevated efficiency of the design process.
Dynamic response optimization algorithm applied to random geometrically mistuned bladed disks
Authors:   Chongqing University, Liang Daosen , Cao Zhifu ,   Chongqing University, Yao Jianyao ,   Chongqing University, Wu Yulin ,   Chongqing University, Jia Zichu ,   Chongqing University, Zhang Xu ,   Chongqing University
Published: February 2024

Unavoidable manufacturing tolerances in bladed disks can lead to geometric mistuning and generate vibration amplification, which can significantly reduce the reliability of the bladed disks. With the development of 3D measurement as well as high-fidelity modeling techniques, it has become convenient to obtain accurate geometric mistuned bladed disk models. However, the blade vibration response is very sensitive to the geometric mistuning parameters, and it is very difficult to optimize the geometric mistuning directly. In this paper, we propose a blade arrangement optimization algorithm to reduce the blade dynamic response amplification caused by the unavoidable geometric mistuning and investigate the influence law of the magnitude of geometric mistuning on the amplification of blade response. We have validated the optimization method by sampling some geometrically mistuned bladed disks through Monte Carlo simulations. The results show that the optimization algorithm can reduce the blade amplitude amplification ratio by more than 5%.
Effects of front small vane on aerodynamic performance of compressor cascade
Authors:   School of Power and Energy, Northwestern Polytechnical University, Feng Hanlin , Mao Xiaochen ,   School of Power and Energy, Northwestern Polytechnical University, Liu Bo ,   School of Power and Energy, Northwestern Polytechnical University, Jiao Yingchen ,   School of Power and Energy, Northwestern Polytechnical University
Published: February 2024

To control the corner separation of compressor stators better, a new flow control method with front small vane on the end wall near the blade leading edge was proposed and investigated. The influence of the front small vane on the flow field and the control mechanism were investigated in a highly loaded subsonic axial compressor cascade. The results show that the front small vane can effectively enhance the flow turning capability in near-wall region, reduce the corner separation and suppress the occurrence of corner stall, which makes huge differences at positive angles (i.e., i=0°~6°). However, the front small vane does not have a significant effect on the flow at negative incidence angles. The wake and the tip scraping vortex of the front small vane are affected by the position of the front small vane in pitchise direction, and they have coupling effects on the corner flow.
Research on the influence of design uncertainty on aeroengine thermodynamic cycle analysis
Authors:   Northwestern Polytechnical University, Xia YiZhen , Zhang YaoZhong ,   Northwestern Polytechnical University, Tu QiuYe ,   Northwestern Polytechnical University, Piao Nuo ,   Northwestern Polytechnical University
Published: February 2024

The sources of aero-engine component performance uncertainty mainly include design uncertainty, manufacturing uncertainty and operating uncertainty. In this paper, the parallel hybrid turbofan engine was chosen as the research object and the Monte Carlo numerical simulation method was adopted to investigate the impact of design uncertainty on the aero-engine thermodynamic cycle analysis. A surrogate model was established to solve the problem that the traditional engine performance calculation model takes too long in the case of large samples. A quantitative evaluation was proposed for schemes in terms of both advancement and realizability. The research showed that the design uncertainty would cause a difference in the scheme's design realization probability. Using the Monte Carlo numerical simulation method to study the impact of design uncertainty on engine performance can simultaneously achieve adjustments to design schemes. Compared with the traditional engine performance calculation model, the surrogate model can save 95% calculation time. The probability evaluation method provided a better and more comprehensive evaluation method for the thermodynamic cycle analysis results and the adjustment scheme after replacing component performance parameters. Due to the input of 1988kw electric power, compared with the conventional turbofan engine, the fuel consumption at the cruise point was reduced by 21.68% and the total temperature before the turbine at the maximum takeoff point was reduced by 12.88%.
Investigation of modified sweeping jet film cooling on turbine vane
Authors:   Shanghai Jiao Tong University, Wang Kechen , Wen Xin ,   Shanghai Jiao Tong University, Zhang Xu ,   Shanghai Jiao Tong University, Peng Di ,   Shanghai Jiao Tong University, Zhou* Wenwu ,   Shanghai Jiao Tong University, Liu Yingzheng ,   Shanghai Jiao Tong University
Published: February 2024

The sweeping Jet (SJ) demonstrates potential applications in film cooling, due to its self-excited sweeping motion. Experiments were carried out to evaluate the cooling performance of the modified SJ and 777-shaped hole. The Fast pressure-sensitive paint (Fast-PSP) technique was utilized to measure the adiabatic film cooling effectiveness distributions over the suction side of the VKI LS89 vane. Carbon dioxide, serving as the coolant, was discharged into one row of holes located on the suction side surface at blowing ratios ranging from M = 0.25 to 0.75. In addition, the film cooling effectiveness of the modified SJ and 777-shaped hole on the pressure side surface at M = 1.0 and 2.5 was measured. The results indicate that the SJ exhibits higher cooling effectiveness values than the 777-shaped hole at both the suction side and pressure side, particularly in the spanwise direction.
Analysis on stall mechanism of axial flow compressor with rotating inlet distortion by dynamic mode decomposition
Authors:   Institute of Engineering Thermo-physics, CAS, Qiu Jiahui , Zhao Yijia ,   Tianjin University, Zhong Yunhong ,   Tianjin University, Zhang Min ,   Institute of Engineering Thermo-physics, CAS, Liu Yang ,   Institute of Engineering Thermo-physics, CAS, Du Juan ,   Institute of Engineering Thermo-physics, CAS
Published: February 2024

To study the impact of rotating inlet distortion on stall mechanism of an axial compressor, the full -annulus unsteady simulation results are analysed using dynamic mode decomposition (DMD). Firstly, the frequency and energy ratio of each mode at near stall condition for the compressor with uniform inflow are obtained. A dominating frequency band 0.3 -0.6 BPF regarded as the characteristic frequency of unsteady tip leakage flow is observed. The distribution of eigenvalues further confirms that there are a few critical unstable modes in the flow field. With further throttling, four large -scale disturbance structures are captured by the second-order mode, whose frequency is twice as the rotor frequency. The circumferential propagation velocity of the stall cell is thus deduced to be about 50% of the rotor speed. Further, when the compressor is subjected to rotating inlet distortion, the change of stalling process is related to the relative position of distortion plate and stall cell according to the DMD mode frequency and shape. The addition of rotating distortion does not change the stall type of the compressor, but the unstable modes indicate that the number and shape of the stall cells have been varied.
An improved fitting-base keyphasor-free blade tip timing method and experimental validation
Authors:   Shanghai Jiao Tong University, Yiming Meng Yiming Meng , Zhicheng Xiao Zhicheng Xiao ,   Shanghai Jiao Tong University, Pengfei Chai Pengfei Chai ,   Shanghai Jiao Tong University, Shang Wang Shang Wang ,   Shanghai Jiao Tong University, Hua Ouyang Hua Ouyang ,   Shanghai Jiao Tong University
Published: February 2024

Blade tip timing (BTT) is a popular non-intrusive blade vibration online measurement technology. Most BTT systems rely on a once-per-revolution (OPR) or keyphasor sensor to provide accurate references. However, such a sensor could be difficult to install due to limited space in field tests. The keyphasor recovery method is the dominant method for keyphasorfree measurements, and several algorithms have been proposed in previous studies, while their accuracy has not been rigorously verified by comparison. In this paper, an improved method based on the linear fitting idea is proposed, and a test rig that can provide the benchmark of the blade tip displacement is designed. The displacement measurement accuracy of the proposed method in this paper is experimentally compared with three other keyphasor-free methods. The results demonstrated that the displacement measurement results of the proposed method are closest to the benchmark under lowspeed acceleration, synchronous vibration and non-synchronous vibration conditions, and the root mean square (RMS) of the measurement error is less than 0.05 mm. This indicates that the BTT is capable of completing long time online health monitoring without keyphasor sensors.
Full annulus simulation on a multistage axial-centrifugal combined compressor
Authors:   Tsinghua University, Tian Cheng , Fu Song ,   Tsinghua University
Published: February 2024

Axial-centrifugal combined compressors are widely used in small and medium aero-engines. This study aims to investigate the performance and flow characteristics of a multistage axial-centrifugal compressor using annulus unsteady simulation. The compressor comprises three axial stages and one radial stage, including the inlet and outlet guide vanes. The simulation employs an in-house URANS solver with a total of 357 million cells. The study analyzes two operating points, at the highest mass flow rate (choke) and near peak efficiency, respectively. The results show satisfactory agreement with the experimental data for the performance parameters of the compressor, such as pressure ratio, isentropic efficiency, and static pressure distribution. The simulation reveals the flow chokes in the radial diffuser, which is characterized by the presence of sonic surfaces occupying the throats of flow passages. Furthermore, two distinct vortices are observed in the radial diffuser, with one vortex axis being oriented vertically to the suction surface and the other being along hub-to-shroud direction. In contrast, the flow maintains a smooth trajectory from the inlet until it exits the impeller. Futhermore, even in scenarios where the compressor operates at choked conditions, the tip vortices of the first rotor manifest a distinctive trait of rotating instability, substantiated by the noticeable presence of a ”hump” within the frequency spectrum of pressure. The study can contribute to a better understanding of the flow behavior in axial-centrifugal compressors and provide insights for their design and optimization.
Interaction mechanism between incoming vortex and tip leakage vortex breakdown of a compressor cascade
Authors:   Northwestern Polytechnical University, Gao Xi , Yang Jing ,   Northwestern Polytechnical University, Cao Zhiyuan ,   Northwestern Polytechnical University, Wang Chuxuan ,   Northwestern Polytechnical University
Published: February 2024

Steady and unsteady simulation are utilized to investigate the interaction mechanism between casing incoming vortex and tip leakage vortex breakdown (TLVB). The incoming vortex is introduced by using vortex generator. Pitchwise location effect and rotating effect are firstly investigated at steady condition; then, unsteady investigation is employed based on the steady results. At steady condition, the TLVB can be completely removed by incoming vortex with stagger angle of 72° and pitchwise location of y3 (the pitchwise distance between blade leading edge and trailing edge of vortex generator is a half of pitch). The flow mechanism is that the vortex core of TLV is replaced by incoming vortex, which has higher strength, and the ability of TLV to withstand adverse pressure gradient is increased. Moreover, tip leakage mass flow near leading edge is also increased because of the increase of blade loading, coupled with the moderate adverse pressure gradient, the reduction of TLVB is achieved. The unsteady fluctuation on blade passage mainly caused by the interaction between incoming vortex and TLV near leading edge. The distribution of pressure near blade surface is also periodical disturbed by incoming vortex, and the fluctuation of pressure is mainly induced by incoming vortex.
Influence of Blowing Ratio on Double-Wall Cooling Characteristics under the Condition of High-temperature Flue Gas
Authors:   Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences, Yi Baichuan ,   University of Chinese Academy of Sciences, Liu Zhigang ,   Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Xiong Yan ,   Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Liu Yan ,   Key Laboratory of Advanced Energy and Power, Institute of Engineering Thermophysics, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Wei Xiaopo ,   Jiangsu Zhongke Research Center for Clean Energy and Power
Published: February 2024

Double-wall cooling structure has been widely studied due to its excellent cooling performance. Most of the previous studies on the cooling characteristics of double-wall have been carried out in the non-reacting conditions without considering the influence of high-temperature flue gas radiation. In this paper, an experiment was carried out to assess the effect of blowing ratio M on cooling characteristics of effusion/impingement cooling at reacting flow conditions. The experiment was performed at atmospheric pressure with adiabatic flame temperature of the flue gas reaching 1800 K. The flue gas temperature was measured by S type thermocouples. The temperature distribution on the wall was measured by an infrared camera and N type thermocouples. The results show that the laterally averaged cooling effectiveness of effusion/impingement cooling system increases with the increase of M. After M>3, the effect on cooling effectiveness is no longer obvious. The laterally averaged cooling effectiveness gradually increases along the flow direction, while its growth rate slows down. Meanwhile, the cooling effectiveness remains basically unchanged after X/D>50.