bluuebunny/crossref_metadata_2025 huggingface dataset:
Mushroom Classification using Random Forest and REP Tree Classifiers
Authors: Paudel Nawaraj , Bhatta Jagdish
Published: August 2022

Mushroom is a popular fruit of a much larger fungus that has a high level of protein and a rich source of vitamin B. It aids in the prevention of cancer, weight loss, and immune system enhancement. There are numerous thousands of mushroom species within the world and a few are eatable and a few are noxious due to noteworthy poisons on them. Hence, it is a vital errand to distinguish between eatable and harmful mushrooms. This paper focuses on comparing the performance of Random Forest and Reduced Error Pruning (REP) Tree classification algorithms for the classification of edible and poisonous mushrooms. In this paper, mushroom dataset from UCI machine learning repository has been classified using Random Forest and REP Tree classifiers. The result based on accuracy, precision, recall and F-measure showed that the Random Forest outperformed REP Tree algorithm as it had highest accuracy value of 100%, precision value of 100%, recall value of 100% and F- measure value of 100%. The performance is 100% by using Random Forest, which is found better with respect to REP Tree classifier.
Availability and Implementation of Instructional Materials in Science Teaching: A Glimpse of Gorkha District
Authors: Kattel Anju , Koirala Kamal Prasad
Published: August 2022

This paper focuses on the availability and implementation of instructional materials in science teaching with the main objectives to find the extent of laboratory and improvised materials used at the secondary level and to assess the practical activities completed by secondary science teachers prescribed in the science curriculum at the secondary level. This study is carried out based on the concept learning of Brunner, the cognition theory of Piaget and Skinner’s operant conditioning learning theory. This study is based on the descriptive survey design to explore the knowledge of teachers and students. For the study, eight public secondary schools within the Gorkha Municipality of Gorkha district were selected purposively and then eight science teachers were selected purposively and forty students selecting five students from each secondary level were selected using a simple random sampling method. A checklist, questionnaire and class observation guidelines were prepared and used to generate data. Data obtained from different tools were analyzed first using simple statistical methods quantitatively, then information obtained from class observation, the interview was analyzed qualitatively making themes and then interpreted linking with prescribed theory. From the data, it was found that most of the schools haven’t sufficient materials in their laboratory. Similarly, most of the science teachers have knowledge but they did not give priority to the improvised materials and did not follow the practical work prescribed in the science curriculum. Teachers can make materials; however, they were found depending upon the marketed science materials neglecting socio-culturally generated materials.
China’s Foreign Direct Investment In South Asia: A Strategic Quest Of China’s Economic Diplomacy
Authors: Kafle Hari Bol
Published: August 2022

China has been South Asia’s strategic consort with economic, diplomatic, and developmental influence. China’s support for South Asia has been seen as truly strategic. It has started to overview the countries of its periphery in a more consolidated may rather than focusing on a separate strategy. FDI, especially for South Asia, is a vital source and means of funds, technology transfer, and skill development. To boost up domestic private and public investment, FDI is essential to carry out steady growth of south Asia. In this research paper, China’s FDI in South Asia has been analyzed and examined from the perspective of China’s expansionary integration, key foreign policy objectives, and key achievements. Empirical analysis has been done. Book, journal articles and reports are reviewed. The key global impacts of China’s economic ascendence and achievements of its FDI diplomacy in South Asia are derived in conclusion. Beijing leverages Belt and Road Initiatives in nearly every country having geo-strategic implications, especially at ports through the Indian Ocean. Moreover, China has made significant effort to assuage periphery diplomacy in the region. Going forward, the South Asian countries should be aware of what Beijing is precisely attempting to achieve in the region, with a view of long-term consequences of the novel plan. To reduce the imbalance of FDI tendency, South Asia should reform their policy to maintain steady growth of FDI and to encourage a large size of capital abandoning export of labor force.
Enhancing The Skill In Stating Research Questions Using A Contextualized Module
Authors: Villonez Glen L.
Published: August 2022

This classroom based action research delved on enhancing the skill in stating a research question in Practical Research 1 subject of Late Afternoon Senior High School students. The study utilized an action research design. This was conducted in Francisco Bangoy National High School during the second semester of school year 2017-2018. Two students were taken into consideration as participants of the study. Baseline data were gathered to assess their performance. Contextualize module was utilized as the tool in helping students master the competency. Also, interview was conducted to validate the results of the quantitative findings. Data were analyzed using Thematic Content Analysis. The findings revealed that students performance after the intervention was implemented has recorded significant increased. Similarly, students claimed that the intervention was helpful and effective in addressing their need. Further, from those meaningful results, it can be reflected that students’ success in the class was largely attributed to the kind of intervention implemented by the teacher which was suited to their need. Undeniably, the use of a module has helped them master the required learning competency. Hence, use of a module may be offered to teachers handling research subject.
Biogas Plants and Its Impact on Rural Life in Nepalese Communities
Authors: Woli Lokendra
Published: August 2022

The main components of development are energy. The manufacturing of biogas is an established technology that is largely used to produce sustainable energy as well as to monetize organic waste. The potentiality of the development of biogas energy is very high in rural Nepalese community and the mainly used for cooking. This article aims to know the impact of biogas plant installation on the community people in their lifestyle including the study area of Lekbesi Municipality - 4 Dasharathpur, Surkhet. Quantitative research design was adopted to meet the objectives and extent of activity as well as the descriptive. Data were collecting through the questionnaire method. The purposive sampling of 72 HHs was taken to gathering the necessary information. The study found that, Biogas plant is a reliable source of renewable energy for limiting deforestation rates, increasing productivity, and protecting the environment from human population increase. The workloads of people, particularly women, have decreased in everyday activities since the installation of the biogas plant, which has had a good impact on the family members’ workload schedules. The current study shows that there is a rising tendency toward reliance on biogas plants, which appears to be solid evidence for the preservation of forest resources. The findings of this article have been helpful for government, non-government, as well as social groups to develop better plans, policies, and practical tactics for providing biogas energy to the poorer sector of rural residents.
गहुँगोरो अफ्रिका कवितामा दलित चेतना {Dalit Consciousness in Wheat Africa Poetry}
Authors: ढुङ्गाना Dhungana लावण्यप्रसाद Labanyaprasad
Published: August 2022

प्रस्तुत शोधलेख आहुतिद्वारा रचना गरिएको ‘गहुँगोरो अफ्रिका’ कवितामा चित्रित दलित चेतनाको अध्ययनसँग सम्बन्धित छ । यस लेखमा सदियौँदेखि उत्पीडनमा पारिएका दलितहरूको प्रतिनिधित्व गहुँगोरो अफ्रिका कवितामा के कसरी गरिएको छ र दलितहरूले आफुमाथि भएको दलनविरूद्ध केकस्तो प्रतिरोध गरेका छन् भन्ने जिज्ञासाको समाधान खोज्ने प्रयास गरिएको छ । यस अध्ययनका लागि आवश्यक प्राथमिक तथा द्वितीयक स्रोतका सामग्रीहरू पुस्तकालयीय कार्यबाट सङ्कलन गरिएका छन् । साथै ओमप्रकाश वाल्मीकि, चमनलाल तथा शरणकुमार लिंबालेका दलित सौन्दर्यशास्त्रीय अवधारणालाई आधार बनाई निष्कर्षसम्म पुग्नका लागि विश्लेषण तथा तर्क विधिको उपयोग गरिएको छ । अध्ययनका क्रममा कवितामा नेपालका सम्पूर्ण भूगोलका र विभिन्न दलित समुदायका कामी, दमाई, च्यामे, गाइने, बादी, मुसहर र सार्कीको प्रतिनिधित्व गरिएको र यिनीहरूलाई बिसौँ शताब्दीका जातीय अस्तित्व चेतयुक्त पात्रका रूपमा उपस्थित गराएर यी पात्रबाट दलनविरूद्ध जुझारू प्रतिरोध गरिएकाले ‘गहुँगोरो अफ्रिका’ दलित चेतनाका दृष्टिले सशक्त कविता बन्न पुगेको निष्कर्ष निकालिएको छ ।
Perencanaan Strategi Pemasaran Tanaman Hias Taman Anggrek Ragunan di Masa Pandemi Covid-19
Authors: Martoyo Anang , Hendrawan Satya Arisena , Hesananda Rizki
Published: August 2022

Penelitian bertujuan untuk merumuskan strategi pemasaran pada pedagang tanaman hias di Taman Anggrek Ragunan, Jakarta Selatan di masa pandemi Covid-19. Metode penelitian yang digunakan adalah deskriptif kualitatif dengan mengidentifikasi permasalahan dan menganalisanya melalui faktor-faktor internal dan eksternal. Alat analisis yang digunakan adalah Matrik SWOT dan Kuadran SWOT. Menurut hasil ’SWOT analysis’ dapat ditentukan bahwa posisi bisnis pedagang tanaman hias di Taman Anggrek Ragunan terletak pada Kuadran 1 (0,52 : 0,90). Hasil ini menunjukkan bahwa bisnis berada pada kekuatan dan peluang yang potensial untuk dikembangkan melalui strategi SO atau strategi agresif.  Adapun formulasi strategi yang dapat diterapkan adalah dengan memanfaatkan lokasi untuk menambah pangsa pasar, mengoptimalkan digital marketing melalui media sosial, marketplace, dan website, kemudian menerapkan strategi product bundling, mempertahankan dan meningkatkan kualitas produk/layanan, membudidayakan sendiri  anggrek bulan dan varian tanaman lainnya, serta  bekerjasama dengan jasa perbankan dalam penyediaan permodalan untuk pengembangan bisnis.
Household Financial Management Behavior During Pandemic Covid 19
Authors: Sulistiyowati Liliek Nur , Dessyarti Robby Sandhi
Published: August 2022

The COVID-19 pandemic has had a tremendous impact on the economic sector in Indonesia, including changes in the composition of household finances. This study aims to assess the impact of the COVID-19 pandemic on household financial management. This study takes the target population of households living in Madiun and its surroundings. The sampling technique used was cluster random sampling. The number of samples is 384 respondents who are proportionally distributed into 5 (five), namely Madiun City, Madiun Regency, Ponorogo Regency, Magetan Regency, and Ngawi Regency, so that the sample taken can generalize the household population in Madiun and its surroundings. Methods of data collection include direct interviews using structured questionnaires. The research approach uses a quantitative approach using one-way ANOVA analysis techniques.The conclusion obtained from the results of the study is that the COVID-19 pandemic has a significant effect on household financial management behavior in Madiun and its surroundings. The average behavior related to household financial management shows that before the COVID-19 pandemic it was 83.27, while during the COVID-19 pandemic it was 73.34. These results show that household economic activities are carried out more often before the pandemic than during the pandemic.
Generation of triangular waveform radiofrequency signals based on photonic filtering using a broad-spectrum source
Authors: Muraoka Espíritu Ramón , Arvizu Arturo , Sánchez López Juan de Dios , Mendieta Jiménez Francisco Javier , Santos Aguilar Joel
Published: August 2022

This work proposes a photonic method to generate optical pulses with a triangular wave shape using a low coherence source. We modulate this source using a sinusoidal radio frequency signal as a local oscillator. We eliminate the second harmonic of the spectral components generated by the modulation process tuning a reject filter to get a triangular wave. We implement the filter using an interferometer with a delay line in one of their branches. To tune the filter, the only adjustment required is over the optical delay line. We developed our scheme in a simulation environment but based on the use of optical and optoelectronic elements with parameters of commercial devices, some of them available in our laboratory. We generate triangular waveform signals with pulse frequencies of 100, 150, 250, and 300 MHz as proof of concept. The proposed scheme has the advantage of being low cost and easy to use because it does not require bias control nor adjustment to  Vpi voltage. Usually, other authors must vary these parameters to get the desired electrical signal. Still, we generate the triangular waveform by adjusting only the local oscillator frequency and the optical delay line. Therefore, because we use a broad-spectrum optical source and do not require a strictly controlled variable voltage, our system will be cheaper.
FOREIGN DIRECT INVESTMENT AND REAL GROSS DOMESTIC PRODUCT: ANALYSIS OF EMPIRICAL EVIDENCE FROM SRI LANKA
Authors: Kengatharan, L.  , Jeyan Suganya, D.F.
Published: August 2022

Foreign Direct Investment is one of the crucial forms of international equity flows for having undeniable growth in gross domestic product among emerging countries. The main objective of the study is to investigate the empirical relationship between foreign direct investment and real gross domestic product in Sri Lanka. Net foreign direct inflow was considered as the independent variable while real gross domestic product was considered as the outcome variable in this study. However, Exchange rate and money supply were selected as the control variables on the relationship between foreign direct investment and real gross domestic product. The current study used annual time series data over the period from 1970 to 2019 which were collected from the annual reports of the Central Bank of Sri Lanka. Stationary of the data was tested using the Augmented Dickey-Fuller test. Johansen co-integration rank test, max Eigen value test, Vector Error Correction (VEC) were used to estimate the relationship between foreign direct investment and real gross domestic product. At the 5% level of significance, the co-integration rank test and max Eigen value test revealed that there is only one co-integration equation existing in the study. Therefore, it was concluded that foreign direct investment has long-run impact on economic growth. Likewise, VEC revealed that foreign direct investment, exchange rate and money supply cause real GDP in the short run. The results support the theoretical prediction that foreign direct investment would play an active role in economic growth as it positively leads to the GDP. The study, therefore, concludes that foreign direct investment is driving the economic growth in Sri Lanka.

 

Keywords: Foreign Direct Investment, Economic Growth, Vector Error Correction Model, Sri Lanka
Sert Mukavva Kapaklı Kitap Ciltleme Terimleri ve Tanımlamaları
Authors: HAYTA Pelin
Published: August 2022

Kitapların bobin ya da tabaka kağıda basıldıktan sonra son haline getirilmesi için yapılan işlemlerin toplamına “Kitap Ciltleme” denir. Geçmişte tamamı elle yapılan ciltleme işlemleri günümüzde tam otomasyonla yapılmaktadır. Baskısı yapılan büyük boyuttaki tabakaya önce kırma, katlama yapılarak forma haline getirilir. Sonra 4-32 sayfadan oluşan bu formalar ardışık olarak harmanlanır. Akabinde dikilerek veya tutkallanarak yekpare hale getirilir. Yekpare haldeki kitabın iç bloğu ayrı hazırlanan mukavva kapak içerisine tutkalla sabitlenerek kitabın ciltlemesi tamamlanır. Teknolojisi çok hızlı ilerleyen ciltleme işlemlerine ait terimlerin anlaşılır şekilde açıklandığı Türkçe bir kaynak maalesef bulunmamaktadır. İnternet tarayıcılarına bakılarak bu görülebilir. Ülkemiz basım sanayii büyük oranda ihracat yapmaktadır. Özel siparişler alarak özgün defter, ajanda gibi çok sayfalı mukavva kapaklı ürünler ihraç etmektedir. Ciltleme işlemlerine ait bir sözlük olmaması yurtiçi ve yurtdışı ticari iletişimde yaşanan sorunlara bağlı maddi kayıplara neden olmaktadır. Özellikle ciltleme işlemlerine ait terminolojinin akademik dille hazırlanmış, tüm paydaşların anlayacağı şekilde bir kaynağının olmaması mesleki iletişimdeki yetersizliğin ana nedenidir. Çalışmada mukavva kapaklı, iplik dikişli bir kitabın teknik yapısı özgün bir çizim üzerinde isimlendirilmiştir. Çizim üzerindeki 16 adet temel teknik terim sade bir dille açıklanmıştır. Sonraki çalışmalarda ciltleme işlemlerine ait diğer terimlerin açıklanması ve nihai olarak kapsamlı bir Matbaa Teknik Terimler Sözlüğü’nün hazırlanması sektörde yaşanan iletişim problemlerini önlemeye yardımcı olacaktır.
Caste, Environment Justice, and Intersectionality of Dalit–Black Ecologies
Authors: Sharma Mukul
Published: August 2022

Caste and race, Dalits and Black people, and the common ground between them have been analyzed in many areas, but their conjunction in the environmental field has been neglected. This article locates Dalit ecologies by examining the close connection between caste and nature. Drawing from a plural framework of environmental justice and histories of environmental struggles among African Americans, it focuses on historical and contemporary ecological struggles of Dalits. It contemplates how their initial articulations under the rubric of civil rights developed into significant struggles over issues of Dalit access, ownership, rights, and partnership regarding natural resources, where themes of environmental and social justice appeared at the forefront. The intersections between Dalit and Black ecologies, the rich legacies of Black Panthers and Dalit Panthers, and their overlaps in environmental struggles open for us a new historical archive, where Dalit and Black power can talk to each other in the environmental present.
TOPICAL ANTIBACTERIAL AGENTS UNDER CONDITIONS OF ANTIBIOTIC RESISTANCE OF THE MICROBIOME (AN ANALYTICAL REVIEW OF THE PROBLEM AND PROSPECTS FOR THE DEVELOPMENT OF NEW TOPICAL ANTIBACTERIAL (ANTISEPTIC) AGENTS)
Authors: Kravchenko V.H. , Kravchenko A.V. , Yemchenko Ya.O. , Dudchenko M.O.
Published: August 2022

The problem of antibiotic resistance is currently one of the most urgent challenges for public health at the global level. An assessment by international experts shows that the resistance of microorganisms to antimicrobial agents is the cause of more than 700.000 deaths annually. Hence, only in the countries of the European Union, more than 25 thousand people die every year from infections caused by antibiotic-resistant bacteria. Despite the widespread use of systemic antibiotics in all fields of medicine, topical treatment of pathological processes continues to successfully serve in dermatology, gynecology, pediatrics, surgery, dentistry, and other areas of healthcare. Worldwide, one can observe a significantly increased interest in the development of topical antiseptic (non-antibiotic by origin) agents and their introduction into clinical practice, both for separate use and in combination with specific medications of systemic action (iodine derivatives, chlorhexidine bigluconate, cidipol, cimesol, etc.). We analyzed the current crisis situation in medicine and its causes related to the progressive polyresistance of the microbiome to antibiotics. The paper provides an overview of modern antibacterial, antibiotic and antiseptic agents on the domestic pharmaceutical market. We draw the attention of scientists and the creative medical community to the insufficient number of domestic innovative developments of antibacterial drugs and the importance of a demanding attitude to antibiotic treatment in connection with polyresistance of microbial flora. The study emphasizes that the development of new non-toxic medicinal products and a wider introduction of already known topical antibacterial, antiseptic, and anti-inflammatory agents with proven effectiveness and a scientifically based application scheme are extremely relevant and necessary under conditions of antibiotic resistance of the microbiome.
DECOMPENSATED URINARY BLADDER DUE TO BENIGN PROSTATIC HYPERPLASIA (LITERATURE REVIEW)
Authors: Sherstyuk O.O. , Sarychev Y.V. , Suprunenko S.M. , Sukhomlin S.A. , Pustovoit G.L.
Published: August 2022

We conducted an analytical review of the literature on the problem of bladder decompensation in patients with benign prostatic hyperplasia. Benign prostatic hyperplasia is one of the most common diseases in aging men. As is known, with the development of benign prostatic hyperplasia due to infravesicular obstruction, the resistance to urine flow increases. As a result of a prolonged overload, the bladder is restructured, and it goes through three successive stages: compensation, subcompensation, and decompensation. Irreversible changes develop in the epithelial, muscular, and nerve tissues of the bladder. With benign prostatic hyperplasia due to intravesical hypertension, persistent microcirculation disorders occur in the walls of the bladder, which leads to the appearance of chronic detrusor ischemia, and can be a predictor of its fibrotic changes and decompensation. There is a correlation between the pathology of the vascular system and the development of symptoms of the lower urinary tract against the background of benign prostatic hyperplasia. Improvement of lower urinary tract perfusion can be considered a therapeutic strategy for the treatment of bladder dysfunction.
PEMANFAATAN LIMBAH AMPAS KOPI DALAM PEMBUATAN SABUN BATANG DI KAMPUNG WISATA KOPI LEREK GOMBENGSARI BANYUWANGI
Authors: Ayu Purwaningtyas
Published: August 2022

Lerek Gombengsari (Lego) Coffee Tourism Village is one of the coffee educational tourism destinations in Banyuwangi. This tourist destination combines agro-tourism and educational tourism so that visitors can learn and practice coffee plantation management organically with an educational system adhering to the principle of Learning by doing. The use of coffee in the Gombengsari area is still limited to coffee beans. Coffee beans are processed into coffee grounds which are enjoyed by tourists, both domestic and foreign tourists. The processing of coffee beans produces 45% of coffee waste in the form of coffee grounds and each cup of coffee drunk containing coffee grounds has an average weight of 20 grams. Therefore, coffee grounds waste must be processed because it can be harmful to health and the environment. Coffee grounds waste contains caffeine, organic acids, minerals and antioxidants that are useful for smoothing the skin, moisturizing the skin and preventing free radicals. Based on these contents, the coffee grounds at Kampung Lego Tourism will be processed into traditional soap bars. Making bar soap is done traditionally to avoid chemicals so that it can reduce problems on the skin. The PKM activity by the Poliwangi Lecturer Team was able to produce processed bar soap products which were packaged under the name Srikandi Homemade Soap. These results are able to add to the list of processed variants that are very useful for partners.
A Numerical Method to Fit the Need of a Straightforward Characterization of Viscoelastic Materials for Marine Applications
Authors: Rognoni Giovanni , Kyaw Oo D’Amore Giada , Brocco Emanuele , Biot Marco
Published: August 2022

In the field of green shipping the reduction of acoustic noise partially transmitted into water and the need of guarantee high comfort levels are important aspects in the view to agree with the UN 2030 Agenda in respect to life below water and good health and well-being. Both these aspects imply actions to increase absorption and dissipation of vibrational energy radiated towards the hull. To accomplish this effect, viscoelastic materials (VEM) characterized by high levels of damping are commonly used on board ships. In the last times, new strict requirements led to the development of Isocyanate free VEM, so the necessity of a provisional method to investigate in an efficient way new VEM is required. Experimental tests are essential in order to obtain performance indicators (non-standard procedure) or material physical characteristics (Oberst’s beam test, ASTM E756 – 05). The implementation of the usual experimental setup could result rather complicated and it needs a high degree of accuracy, so in the last times finite element methods (FEM) has been increasingly used. Knowing VEM physics parameters allows numerical simulation in both the provisional and the optimization phase to be accurate and reliable. In this paper, an experimental-numerical method is proposed, with the aim of overtake the issues linked to the small-scale traditional cantilever beam test and paving the way to the selection of the most appropriate shape of the specimen. The innovation proposed through this method lies in the evaluation of the VEM complex modulus based on a reverse engineering approach, in which the loss factor estimation, contrarily from the traditional methods, is free from peak sharpness dependence. The proposed procedure is validated by comparison with the traditional method.
ARGOS: A Solution to Increase Security and Safety of Ships
Authors: Gottifredi Franco , Cappella Marco , Marcinek Krzysztof , Anton Alina , Amerio Barbara
Published: August 2022

In the last years, the leisure vessels market had a very positive trend and, every year, more and more ships will be present in our waters. This is giving a push to the demand and needs of increased security, in the protection against theft, and safety, in the protection against losing the mooring while anchored with the risk of having accidents against rocks or other vessels. The ARGOS Solution is offering the capabilities and performance to answer those needs with easy plug-in installation of a device in the boat. The ARGOS Solution is under development in the frame of the ARGOS (Anti-theft Robust Galileo-based Operational System) project co-funded by the EU Agency for the Space Programme (EUSPA) within its Fundamental Elements funding programme. The ARGOS Solution, leveraging the services provided by Galileo and thanks to its scalable and modular architecture, provides timely alerts in case of theft or risk of losing the mooring of the anchor point. It also provides high robustness against environmental conditions, e.g. multipath, shadowing of the GNSS signals, etc…, and external factors that can be unintentional (e.g. interference sources) or intentional (e.g. jamming or spoofing attacks in order to support a theft attempt). These differentiating capabilities are based on the new features of Galileo, the European GNSS system, specifically the Open Service Navigation Message Authentication (OSNMA) that will increase the robustness against certain types of spoofing attacks, and the I/NAV Message improvement that will increase the performance of the GNSS signal processing in harsh environments (e.g. ports, natural harbours, etc…). These capabilities are integrated in the solution and improved with an advanced Navigation Engine in the ARGOS device by fusing the GNSS information with data from other on-board sensors (e.g. Inertial Measurement Unit) in order to provide timely alerts with high performance detection of risky conditions.
Deep Neural Network (DNN) Method to Predict the Displacement Behavior of Neutral Axis for Ships in Vertical Bending
Authors: La Ferlita Alessandro , Di Nardo Emanuel , Macera Massimo , Lindemann Thomas , Ciaramella Angelo , Kaeding Patrick
Published: August 2022

The shifting of the neutral axis in the cross section of ship structures is an important result of progressive collapse analyses. The main purpose of the present study is to apply a Deep Neural Network (DNN) method to linear systems and estimate in a relatively short time span the shift of the neutral axis for intact and damaged ships. First, the initial source data related to the intact condition and to several symmetric damaged grounding scenarios of five different vessels (Double Hull Oil Tanker, Single Hull Tanker, 1350TEU Container Vessel, 3500TEU Container Vessel, Bulk Carrier) have been determined with a self-developed code based on the well-established Smith method. With the application of the DNN, the shift of the neutral axis has been predicted for a set of completely new damage scenarios of a ship cross section, demonstrating that the deep neural network approach can estimate the neutral axis performance. The successful prediction obtained within this paper will lead to the DNN’s application for computing the ultimate strength capacity.
Ammonia as an Alternative Fuel for Large Passenger Ships: Benefits and Challenges
Authors: Scamardella Filippo , Zamboni Giorgio , Canepa Edward , Gualeni Paola , Macocco Angelo
Published: August 2022

The shipping industry is under increasing pressure to comply with new demanding requirements for exhaust gas emissions. Alternative fuels as well as new technologies need to be developed to meet these goals and reduce Green-House Gases (GHG). This paper investigates ammonia as an alternative fuel for the cruise ship market. A focus is given on the regulatory framework (e.g. EU, IMO and Classification Societies) that at present defines requirements for gaseous emissions and design principles of the fuel containment as well as supply systems. Ammonia allows for effective reduction of CO2 but is potentially toxic for human life and the environment. Due to the innovative nature of ammonia as a fuel, the regulatory approach is based mainly on alternative design instead of prescriptive rules. A case – study, with Internal Combustion Engine ICE (Dual-Fuel) and Propulsion Electric Motors (PEM) as selected standard propulsion system, has been carried out to investigate the impacts of ammonia as fuel on a large passenger ship. The purpose is to evaluate the variation of navigation autonomy, arrangement and weights/stability, considering also specific storage and handling requirements.
BESS-Based Hybrid Propulsion: An Application to a Front Line Naval Vessel Preliminary Design
Authors: Belvisi Daniele , Zaccone Raphael , Figari Massimo , Simone Sergio , Spanghero Bruno
Published: August 2022

The paper conceives a flexible new generation naval ship Destroyer (DDX, Destroyer, Experimental) with a primary focus on low environmental footprint, high efficiency, and reliability. The ship implements an innovative propulsion power generation and storage system based on a CODOGOL (COmbined Diesel Or Gas Or eLectric) architecture and a Battery Energy Storage System (BESS). The proposed modular solution is also suitable for retrofitting applications and represents an innovation in the state of the art of hybrid propulsion systems for big, front-line naval ships. The shipboard BESS is used as a backup power source to ensure minimum generator operation (MGO) mode reliability requirements. The benefits of the proposed solution are discussed in detail, highlighting a reduction of the operating costs and fuel consumption, as well as low pollutant emissions and Life Cycle Costs. Eventually, dynamical simulation is used to assess the effectiveness of the proposed solution in critical conditions.
A Zero-Emission Ferry for Inland Waterways
Authors: Maloberti Luca , Zaccone Raphael , Gualeni Paola , Mazzucchelli Paolo
Published: August 2022

Reducing the human environmental impact is one of the most critical issues nowadays: in this perspective, the progressive decommissioning of fossil fuels is a significant priority to guarantee a sustainable future for the next generations. This paper proposes a zero-emission ferry for inland waterways and short-sea navigation, focusing on realistic solutions to provide the best trade-off between operational performance and environmental sustainability. In particular, the object of this study is the refitting of a double-ended ferry working in the Lago Maggiore, one of the largest Italian lakes. Systems suitable for the purpose have been selected and integrated onboard to maximize efficiency, implementing full-electric propulsion with electric motors, a Li-ion battery storage system, and photo-voltaic panels. The benefits and drawbacks of the considered technologies have been evaluated to select the most promising design solution, focusing on both onboard and on-shore impact in terms of compatibility with the existing infrastructures and considering life-cycle sustainability.
Experimental Investigation on a Lightweight Ship Balcony Overhang with Bimetallic Welded Joints
Authors: Palomba Giulia , Corigliano Pasqualino , Crupi Vincenzo , Epasto Gabriella , Guglielmino Eugenio
Published: August 2022

Integration of lightweight and sustainable solutions in marine structures design is essential to achieve weight reduction goals and improve structural response. A key step to assess the reliability of innovative structural solutions is represented by large-scale experimental investigation. The current paper deals with the analysis of a lightweight ship balcony overhang, which includes an aluminium honeycomb sandwich structure and bimetallic welded joints. The design of the ship balcony overhang was previously performed, as an illustrative example, with the aim of suggesting the replacement of common marine structures with more green and lightweight alternatives. In order to validate the design procedure and to assess the feasibility of the suggested solution, an experimental investigation on a large-scale structure was performed. The ship balcony overhang was tested under bending with a configuration representative of severe loading conditions for ships balconies. The experimental analysis allowed the evaluation of the structure’s strength, stiffness and failure modes, which are useful data to improve the design methodology of such structures and to calibrate numerical models. Comparison with similar structures reported in literature were performed in order to assess the benefits and drawbacks of the suggested lightweight structure.
On the Structural Response of Bio-Based Adhesives for Wooden Hulls
Authors: Bertagna Serena , Corigliano Pasqualino , Crupi Vincenzo , Marinò Alberto
Published: August 2022

In the last years, the idea of implementing greener and sustainable solutions merged with the basic principles of life cycle assessment concept has turned to be of paramount importance for the boatbuilding industry. In this framework, construction technologies based on wood such as strip-planking represent possible solutions, as they allow the use of a natural-grown material for attaining refined and solid structures. However, since these techniques imply wood bonding through conventional epoxy adhesives, the global eco-friendliness of the final product is lowered. As a consequence, the adoption of innovative bio-based adhesives is a promising solution to investigate. It is known that, generally, bonded joints in wooden hulls are weak spots of the structure, so the performances of the used adhesives should be duly assessed in order to guarantee an effective bonding. In the present research activity, the assessment of the performances of bonded joints manufactured with bio-adhesives is carried out through a FEM-based methodology, starting from the data present in both technical datasheets and literature for the materials used. In such a way, the most promising products can be preliminarily identified in order to deeply investigate their mechanical characteristics through experimental tests, so limiting expensive and time-consuming activities. The proposed methodology was validated through the comparison between the results coming from the FE analysis and the ones stemming from experimental tests. Moreover, the proposed methodology could be profitably used to analyse more complex geometries, such as real and large structures of wooden hulls.
Regulatory Measures to Tackle Climate Changes
Authors: Carosi Giovanna
Published: August 2022

Until the Industrial Revolution, the concentration of greenhouse gases (GHG) (Carbon Dioxide, Methane, Nitrous Oxide, Ozone) in the atmosphere was quite constant; then human activities – such as burning of fossil fuels, industrial operations and deforestation – increased their concentrations, enhancing the natural greenhouse effect. According to the majority of the climate scientists, the warming observed since mid-20th century is mainly caused by human influence and there is a tight link between GHG pollution and global warming. Recognizing the far-reaching and long-lasting consequences of the global warming for the planet, intense international debates at all levels take place to find possible responses to mitigate GHG emissions and reduce global warming effects. The paper will present the high-level goals agreed at the UN Climate Changes Conferences (e.g. COP21 (Paris Agreement) and COP26) that boosted the discussion in important maritime fora and will critically review the new important and significant regulatory measures taken by the International Maritime Organization (IMO) and the European institutions and their impact on the maritime transport. It will cover the IMO already adopted short-term measures (i.e. EEXI and CII) and the medium and long-term ones currently under discussion, such as carbon levy, life-cycle assessment and market-based measures. A view on the very demanding climate targets in the EU for 2030 and 2050 (set by the European Climate Law adopted in June 2021) and the so-called “Fit for 55 Package” included in the legislative proposals to meet the 2030 objectives, will also complete the picture.
Classifying the Innovation: The Certification of New Designs for Power Generation, Conversion and Energy Storage Focusing on the Reduction of Ships Emissions
Authors: Roiaz Matteo , Scialla Paolo , Cadenaro Fabrizio , Nardo Marco , Sancin Gabriele
Published: August 2022

In recent times the ship building and yacht industries have seen a surge in the requests for the application to the power generation, conversion and energy storage of technologies which were previously reserved to land-based uses or to niche sectors such as space, military, and scientific research. Such requests are often driven by seeking cleaner exhaust emissions, more efficient fuel consumption and higher passenger and crew comfort. Among these novel technologies we can mention fuel cells and (large) batteries based on Li-ion chemistries. These solutions are not only unconventional per se, they also carry along the necessity for advanced electrical system integration (even more so if combined in a hybrid architecture) or, for fuel cells, the need for the storage of dedicated fuels, e.g., liquid, or compressed hydrogen or methanol, and fuel treatment, e.g., evaporators and chemical reformers. The lack of prescriptive regulations covering such innovative solutions, both in terms of equipment and fuel, adds in challenge to their acceptance and certification from Regulatory Bodies and Flag Administrations. Furthermore, although high-level guidelines are provided, they often need to be tailored on a case-by-case basis and integrated with risk assessment exercises. The aim of this work is to give a comprehensive overview of the Classification tools available to date – be it prescriptive or risk-based – for the approval of novel designs and how do they relate to the existing statutory guidelines and to the established risk analysis instruments. The discussion will be corroborated by insights into some hands-on case studies in the yacht and cruise ship industry segments.
Free Surface Hydrodynamics of Submarine Masts Configurations
Authors: Vernengo Giuliano , Gaggero Stefano , Villa Diego , Mazzarello Giorgio , Gualeni Paola
Published: August 2022

Sailing at snorkel depth is a necessary but dangerous operating scenario for submarines. The main and straightforward reason is that such an operating condition represents a time of possible vulnerability of the vessel. From a design perspective this condition affects the so-called indiscretion rate, that is exactly the ratio between this time of greater vulnerability and the total operating time. Moreover, when the vessel operates at snorkel depths there are some relevant operations that might be accomplished related to both snorkeling, communications and threats detection. These operations are typically carried out by using a certain number of masts, of slightly different shapes and sizes, that might be used in various configurations. The proposed study aims at providing some insights into the unsteady, turbulent, hydrodynamics of several submarine masts configurations. The analysis is carried out in terms of behaviors of the developed free surface, considering the nonlinear interactions rising among the masts considered. The maximum height and length of the breaking wave generated at the bow of each mast is analyzed. Both the near field and the far field unsteady wave patterns are discussed comparing several configurations and focusing on the interaction effects. The computational study is carried out by using an open-source Smoothed Particle Hydrodynamic solver called DualSPHysics, able to exploit the computational acceleration provided by GP-GPU cards.
Hybrid System Virtualisation for Predicting Performance and Eliminating Risks and Uncertainties
Authors: Palma Amodio , Goranov Stefan , Wenig Markus , Bendyk Maciej
Published: August 2022

Nowadays, the topic of hybrid marine energy systems is becoming increasingly relevant – this trend is mostly driven by the constant demand for safer and more efficient powertrains while being further accelerated by initiatives like zero-emission shipping [1], the initial IMO GHG 2050 strategy [2] or such instruments as EEDI, EEXI or CII [3] [4]. In this respect, the present study focuses on the domain of ocean-going vessels propelled by large 2-stroke marine engines and, in particular, on the challenges of a properly integrated propulsion system [5]. Virtualising the integrated system, using transient-capable components models provides plausible quantitative figures about its performance and enables informed decisions at early stage. To this end, the paper highlights two findings – first, the importance of component “rightsizing” and, second, the necessity for intelligent operation of those components. Embarking on an analysis of a wide range of customer studies for various vessel types (PCTC, Container, LNGC, etc.) it is demonstrated how each use case may lead to another optimal solution. For instance, utilizing the power-take-off (PTO) functionality for genset replacement might be generally feasible but its efficacy, due to the interaction of main engine and shaft generator, depends highly on the intended vessel operation. Another example is the arguably inefficient peak shaving functionality which, if only applied in a suitable situation (e.g. for genset load balancing), still may provide benefit to the overall system efficiency. The paper remarks the importance of a virtual tool to support the hybridisation of marine vessels. Such tool allows for the identification of potential risks and criticalities in a very early stage as well as for reduction of calibration effort and risk of failure during commissioning.
A Multipurpose Simulation Framework for Ship Design and Operational Assessment
Authors: Isgro Luca , Fengone Luca , Tozzi Davide
Published: August 2022

One definition of simulation is: an approximate imitation of the operation of a process or a system. It is very easy for us to understand the concept of simulation and in fact Simulation, Virtual Reality and Mixed Reality often become the most effective and immediate ways to understand our reality. There are many kinds of simulation but in CETENA, when we talk about simulation solutions, we refer to maritime real-time simulation that can be used in different applications and fields.
Assessment of Shipboard Sound Insulation in the Low Frequency Range Through a Laboratory Experimental Methodology Based on a Modal Approach
Authors: Bassetti Mirko , Gaggero Federico , Prato Andrea , Schiavi Alessandro , Pais Tatiana , Silvestri Paolo , Lembo Enrico
Published: August 2022

In recent years a growing need in naval acoustics for the characterization of low frequency materials below 100 Hz and particularly from 50 Hz has been observed. The problem related to airborne and impact acoustic insulation at low frequencies is becoming more and more relevant due to the considerable impact of sound sources at these frequencies, such as audio-video systems in theaters and discos as well as TV systems inside cabins. Current measurement procedures for identifying the sound insulation properties of bulkheads and floors are not sufficient to ensure repeatable and reproducible measurements, as accuracy and precision values are too low to be accepted when applied at frequencies below 100 Hz. In fact, at low frequencies and in ordinary laboratory or room volumes between 40 m3 and 80 m3, the acoustic field is no longer diffuse due to the dominant presence of standing waves or modes, which result in large fluctuations of the sound pressure level in space and frequency. In the present study, an experimental methodology based on the modal approach is proposed and applied for the study of low-frequency sound insulation phenomena below 100 Hz in the naval field. An extensive experimental activity has been conducted at CETENA laboratories in Riva Trigoso, which has allowed to validate the measurement procedure and compare it with classical theories of sound transmission. The development of this approach seems to be able to provide significant support in the design phase for the optimization of shipboard sound insulation performances.
Application of Transfer Path Analysis Technique to Cruise Ships
Authors: Bassetti Mirko , Tonna Riccardo , Pais Tatiana , Silvestri Paolo , Lembo Enrico , Iuliano Andrea
Published: August 2022

The transfer path analysis (TPA) method is considered to be an important and effective tool for identifying vibration and noise (VN) sources and main transfer paths. This technique is commonly developed and well-established in the automotive field. In contrast it has not been applied to in naval architecture yet, accounting for the complexity of the path, the higher number of the receivers’ locations and the many sources on board (e.g. engine, propeller, generator, pumps…). In this paper, the Polytechnic School of the University of Genoa, together with Cetena, presents a preliminary approach for applying the TPA technique in the marine field to a cruise ship. After a comprehensive review of the method, the results of the TPA application are presented by analysing the measurements taken during a sea trial.