• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.4
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• pp.79-88
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• 2020

Hypergolic propellants have been widely used for space propulsion systems based their long-term storability and high ignition reliability. Since conventional hypergolic propellants are highly toxic and carcinogenic, handling and operating costs are significant. To overcome the drawbacks, numerous studies have been actively performed to develope new hypergolic propellants, ensuring that the combinations are high performance, low toxicity and low environmental impact. In the present study, a comprehensive survey was conducted to summarize the research and development of green hypergolic propellants involving hydrogen peroxide, nitric acid, and ionic liquids.

• International Journal of Computer Science & Network Security
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• v.21 no.2
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• pp.21-39
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• 2021

The acceptance of smartphone applications in the learning field is one of the most significant challenges for higher education institutions in Saudi Arabia. These institutions serve large and varied sectors of society and have a tremendous impact on the knowledge gained by student segments at various ages. M-learning is of great importance because it provides access to learning through a wide range of mobile networks and allows students to learn at any time and in any place. There is a lack of quality requirements for M-learning applications in Saudi societies partly because of mandates for high levels of privacy and gender segregation in education (Garg, 2013; Sarrab et al., 2014). According to the Saudi Arabian education ministry policy, gender segregation in education reflects the country's religious and traditional values (Ministry of Education, 2013, No. 155). The opportunity of many applications would help the Saudi target audience more easily accept M-learning applications and expand their knowledge while maintaining government policy related to religious values and gender segregation in the educational environment. In addition, students can share information through the online framework without breaking religious restrictions. This study uses a quantitative perspective to focus on defining the technical aspects and learning requirements for distributing knowledge among students within the digital environment. Additionally, the framework of the unified theory of acceptance and use of technology (UTAUT) is used to modify new constructs, called application quality requirements, that consist of quality requirements for systems, information, and interfaces.

• International Journal of Computer Science & Network Security
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• v.22 no.1
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• pp.21-26
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• 2022

This study touched on the effect of the different electronic course designs on the programming skills of university students. The researcher used the experimental research design of a quasi-experimental of two experimental groups to achieve the objectives of the study. The first group underwent an electronic course designed in the holistic pattern, and the second group was taught a course in a sequential pattern. This experimental design was intended to measure the impact of these two learning modes on the learners' cognitive and performance achievement of programming skills. An achievement test and observational form were the data collection tools. Data were analyzed statistically using Pearson correlation, Mann Whitney Test, and Alpha Cronbach. The findings revealed statistically- significant differences between the mean scores of the students of the first and second experimental groups in favor of the former concerning the observational form and the latter in the cognitive test. Based on the findings, some recommendations are suggested. Due to their effectiveness in the educational process, expanding using the e-courses at universities is vital. The university teachers are highly recommended to design e-courses and provide technical and material support to the e-courses user to fulfill their design purpose.

• Journal of Chest Surgery
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• v.54 no.6
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• pp.439-448
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• 2021

Remodeling is a commonly encountered term in the field of cardiothoracic surgery that is often used to describe various pathophysiological changes in the dimension, structure, and function of various cardiac chambers, including the aorta. Stanford type A or DeBakey type 1 aortic dissection (TAAD) is a perplexing pathologic condition that can present surgical teams with the need to navigate a maze of complex decision-making. Ascending or hemi-arch replacement leaves behind a significant amount of distal diseased aortic tissue, which might have a persistent false lumen or primary or secondary intimal tears (or communications between lumina), which can lead to dilatation of the aortic arch. Unfavorable aortic remodeling is a major cause of distal aortic deterioration after the index surgery. Cardiac surgeons are aware of post-surgical cardiac chamber remodeling, but the concept of distal aortic remodeling is still idealized. The contemporary literature from established aortic centers supports aggressive management of the residual aortic pathology during the index surgery, and with continuing technical advancements, endovascular stenting options are readily available for patients with TAAD or for complicated type B aortic dissection cases. This review discusses the pathophysiology and treatment options for favorable distal aortic remodeling, as well as its impact on mid- to long-term outcomes following TAAD repair.

• Journal of Arbitration Studies
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• v.32 no.2
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• pp.115-133
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• 2022

This article examines the Practical Suggestions for Promoting of Virtual Hearings in International Arbitration. COVID-19 had an prompt and meaningful impact on the practice of international arbitration. Nevertheless arbitral institutions, arbitral tribunals, and other participants learned quickly how to deal with this new challenge. The use of virtual or online hearings has been gaining popularity during the COVID-19 pandemic. Either with the help of arbitral institutions or by themselves, the parties realized that the only way to safeguard a hearing at all was to run it virtually. In fact, hearings by video conference or other technical means seemed to be the magic solution. One of the leading arbitration institutions, i.e. the International Chamber of Commerce in Paris has amended its Arbitration Rules to accept the subjects of recent international arbitration practice. Other arbitral institutions have similarly amended their respective rules. Many recent and adaptable institutional arbitration rules, either expressly or implicitly, allow for hearings to be conducted remotely. The trend has already been set by the leading institutions as ICC, LCIA, ICSID, SCC SIAC, and many more will follow. In short, enthusiasts of virtual hearings even believe that virtual hearings are "the new normal".

• The Journal of Asian Finance, Economics and Business
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• v.10 no.2
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• pp.223-233
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• 2023

Entrepreneurship brings countless values to each individual and practical benefits to society and the economy. Recently, the call for a better understanding of entrepreneurship from corporations and governments is regularly voiced the day, both in the academic literature and in public discussions. This study examines factors influencing the startup decision of young people in Vietnam. Primary data was collected from an online survey and then imported into an Excel file before being analyzed by SPSS 22. The total number of relevant observations for the study is 656, using numerous statistical approaches such as EFA and multiple regression analyses. This study contributes to the existing literature and current practice by suggesting six major determinants of startup intention: self-expectation, personal attitudes, self-competency, perceived feasibility, entrepreneurial orientation, and financial wealth. Among these factors, self-competency and entrepreneurial orientation are statistically significant, indicating that the capability of young people is the most important determinant of their startup intention. Additionally, the results indicate that self-expectation, attitude, perceived feasibility, and finance do not impact students' intention to pursue entrepreneurship. We suggest that by enhancing the training quality of universities, young people will be provided with much essential knowledge and technical skills for running a business.

• International Journal of Computer Science & Network Security
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• v.22 no.6
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• pp.13-18
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• 2022

Mankind has been living in the third millennium of a new era for 15 years. Today he realized that he was on a tiny planet with not much space. The 20th century laid bare its global consequences in all its horror.. According to the Stockholm International Peace Research Institute, more than 30 armed conflicts are recorded on the planet every year, leading to the death of more than 1,000 people during the year. Over the past 15 years, the total number of deaths as a result of military actions in such conflicts has also increased: more than 17 thousand people - in 2002 to more than 22.5 thousand - in 2011. 2022, in turn, became the beginning of a new round of military history, bringing changes in the social, environmental, agro-industrial, economic and other spheres not only in Ukraine, but also in all countries of the civilized world. As a result of the study, the most significant impact of the negative factors of the war, namely the economic, legal, regional and environmental aspects, was identified and analyzed.

• Advances in nano research
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• v.12 no.6
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• pp.567-581
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• 2022

The free and forced vibration in addition to electric energy harvesting of a piezoelectric disk resting on two-parameter foundation modeled by modified couple stress as well as Kirchhoff plate theory is probed. The governing equations and boundary conditions are obtained using Hamilton's principle. Then, the free and forced vibration are solved using numerical solutions, generalized differential quadrature method (GDQM) and Newmark-beta method. The forced vibration is resulted from a base excitation load. Also, the possible voltage which can be harvested from this system is obtained using generalized integral quadrature method. The validity of the formulation and solution procedure is confirmed using a compassion study. The impact of parameters such as length effect, inner to outer radius ratio, and foundations parameters on the free and forced vibration as well as energy harvesting is investigated in detail. This paper can be a basis for future studies in the area of piezoelectric harvesters in small scales.

• Journal of Korea Multimedia Society
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• v.25 no.9
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• pp.1356-1366
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• 2022

In the display of virtual space, the degree of space virtualization cannot be judged only by the degree of material technology. Based on the non-material relationship, the virtual space that this research focuses on is a conceptual and ontological point of view (based on the conceptual and ontological viewpoints of non-material relations), including practical technical issues. The research on the characteristics of virtual space ontology not only has an impact on the space design of science fiction movies, but also becomes a powerful medium that brings changes to the world. In the future, there will be a large number of cases where fantasy things in science fiction movies are actualized. From this perspective, based on the study of several science fiction movies using virtual reality scenes, this paper puts forward a study on the representation characteristics of virtual space ontology. In addition, the study of the virtual reality is of great significance for verifying the possibility of virtual reality in the application of deep space technology in the future. At the same time, it provides reference value for the development of special effects film field from montage theory-based to Bazin theory-based expression, and contributes to the theoretical system of film space.

• Structural Monitoring and Maintenance
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• v.9 no.4
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• pp.305-321
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• 2022

Bridge structural health monitoring with the aim of continuously assessing structural safety and reliability represents a topic of major importance for worldwide infrastructure managers. In the last two decades, due to their potential economic and operational advantages, drive-by approaches experienced growing consideration from researcher and engineers. This work addresses two technical topics regarding indirect frequency estimation methods: bridge and vehicle dynamics overlapping, and bridge expansion joints impact. The experimental campaign was conducted on a mixed multi-span bridge located in Lombardy using a Ford Galaxy instrumented with a mesh of wireless accelerometers. The onboard time series were acquired for a number of 10 passages over the bridge,performed at a travelling speed of 30 km/h, with no limitations imposed to traffic. Exploiting an ad-hoc sensors positioning, pitch vehicle motion was compensated, allowing to estimate the first two bridge bending frequencies from PSD functions; moreover, the herein adopted approach proved to be insensitive to joints disturbance. Conclusively, a sensitivity study has been conducted to trace the relationship between estimation accuracy and number of trips considered in the analysis. Promising results were found, pointing out a clear positive correlation especially for the first bending frequency.