bluuebunny/crossref_metadata_2025 huggingface dataset:
Análisis de la cadena de valor en el sector agrícola. Caso PACAT
Authors: Valencia Silva Alex , Morales Diana , Mostacero Janett
Published: July 2024

En este trabajo de investigación se aborda el análisis de la cadena de valor en el sector agrícola, centrándose en el caso de estudio de los Productores Agroecológicos y de Comercialización Asociativa de Tungurahua (PACAT). Se busca comprender la estructura y funcionamiento de esta cadena, identificando actividades clave y posibles oportunidades de mejora para incrementar la competitividad en el mercado agrícola. Este análisis permitirá obtener una visión integral de la empresa y su entorno, proporcionando información valiosa para la toma de decisiones estratégicas. El estudio detallado de cada etapa de la cadena permitirá identificar áreas de eficiencia y posibles puntos de mejora, lo que contribuirá a optimizar los procesos y a maximizar el valor agregado en cada eslabón. Además, se considerarán las relaciones con los diferentes actores involucrados, como proveedores, distribuidores y clientes, con el fin de fortalecer la colaboración y mejorar la coordinación en toda la cadena. Asimismo, se analizarán las tendencias del mercado agrícola y se evaluarán las oportunidades y desafíos que puedan surgir en el futuro cercano, con el objetivo de anticiparse a los cambios y adaptar la estrategia de la empresa de manera proactiva.
Papier- oder computerbasierte Kompetenztests? Eine Generalisierbarkeitsstudie zu Moduseffekten in Deutschland im Rahmen von TIMSS 2019
Authors: Jentsch Armin , Beese Christin , Schwippert Knut
Published: July 2024

Die zunehmende Digitalisierung in Deutschland ist insbesondere in den Lernumwelten von Schüler:innen zu beobachten. So haben auch Schulvergleichsuntersuchungen zuletzt von papier- auf computerbasierte Tests umgestellt. In TIMSS 2019 wurde diese Umstellung durch eine Moduseffektstudie begleitet. Zwei Jahre vor der Haupterhebung nahmen 847 Viertklässler:innen an dieser Studie teil und bearbeiteten nach dem Zufallsprinzip entweder zuerst den papier- oder den computerbasierten Kompetenztest in Mathematik und den Naturwissenschaften. Wir gehen in diesem Beitrag der Frage nach, inwieweit der Lösungserfolg bei der Aufgabenbearbeitung vom Erhebungsmodus abhängt. Wir führen dazu erstens eine Generalisierbarkeitsstudie durch und bestimmen den Anteil der Varianz in den Schüler:innenantworten, der auf Moduseffekte zurückgeht. Zweitens wird untersucht, ob die Zusammenhänge zwischen schwierigkeitsgenerierenden Merkmalen der Testaufgaben und dem Lösungserfolg der Schüler:innen von Moduseffekten betroffen sind. Die Ergebnisse zeigen, dass die Erfassung der Schüler:innenkompetenzen in beiden Domänen mit kleinen Moduseffekten einhergeht. Der Lösungserfolg ist in den computerbasierten Leistungstests etwas niedriger (Mathematik: OR = 0.87, p = .006, Naturwissenschaften: OR = 0.86, p = .006). In Mathematik gilt dies besonders für Aufgaben in den Bereichen Daten und Problemlösen, für die Naturwissenschaften lässt sich keine entsprechende Aussage treffen. Die Bedeutsamkeit dieser Befunde für Schulvergleichsuntersuchungen und die unterrichtliche Praxis in Deutschland wird im Beitrag kritisch diskutiert.
A Critical Review in Infectious Disease and Mathematical Modelling
Authors: Adhikari Arjun
Published: July 2024

Infectious diseases control and prevention relies on a thorough understanding of the factors determining transmission. The transmission dynamics of infectious diseases is susceptible to changes governed by several factors, whose recognition is critical for the rational development of strategies for prevention and control, as well as for developing health policies. This article summarizes the fundamental principles of infectious disease transmission and compartmental models. Basic principles of infectious disease diagnosis, reasons for formulating the infectious diseases and historical facts on epidemics are also reviewed.
People's Multi-party Democracy: A Success Story of the Communist Movement of Nepal
Authors: Gyanwali Gokarna Prasad , Khanal Khem Raj
Published: July 2024

The 1990s was a crucial time in the global communist movement that faced a serious setback after the collapse of the USSR and other East European communist and socialist governments. In Nepal, communist parties allied with the Nepali Congress, a democratic party to stage the people’s movement to end active monarchy and restore democracy. The call for the people’s movement by the parties appealed the people and they took part in the movement in a historic way. That movement succeeded to restore democracy and end the active monarchy. Madan Bhandari, the secretary-general of the Communist Party of Nepal (Marxist and Leninist) witnessed this unprecedented participation of the people in a peaceful democratic movement and realized the need to democratize the communist movement, so that, they could build people’s trust towards communist parties. In the general election held in 1991, communist parties won forty percent of the seats in the parliament and popular votes as well. In this context, Bhandari presented the document of people’s multi-party democracy in the fifth national congress of the Communist Party of Nepal (Marxist and Leninist) held in 1993, and it was passed overwhelmingly in the congress. This article attempts to make a textual analysis of the document of People’s multi-party democracy to examine the major aspects of the document and to see how successful it has become in democratizing the communist movement in Nepal.
Effect of Working Environment on Job Satisfaction of Employees in Nepal Electricity Authority
Authors: Basnet Deepak
Published: July 2024

Organization is facing several challenges due to the dynamic nature of the environment in this modern era. The major challenge for a business is to satisfy its employees in order to cope up with the ever changing and evolving environment and to achieve success and remain in competition. The business must satisfy the needs of its employee to increase the efficiency, effectiveness, productivity and job commitment by providing good working conditions. The aim of this research is to examine the effect of working environment on employee job satisfaction. This research employed a quantitative methodology. The required data were collected through a self-administered survey questionnaire. The target populations are the employees of Nepal Electricity Authority and only 108 employees were taken as sample using convenience sampling method. The result indicates that there is positive relationship between working environment and job satisfaction. The study also concludes that with some brief prospects that the businesses need to realize the importance of good working environment for maximizing the level of job satisfaction. This research may benefit to society by encouraging people to contribute more to their jobs and may help them in their personal growth and development. Hence, it is essential for an organization to motivate their employees tow work hard for achieving the organizational objectives and goals.
Sanskritization in Nepal: The Impact of Social Stratification
Authors: K.C. Raju
Published: July 2024

Social stratification is the division of people into various groups or strata in a community according to their cultural beliefs, traditions, or occupation. Both in Nepal and all throughout the world, it is a widely accepted practice. M. N. Srinivas introduced the idea of "Sanskritization," which refers to the lower caste adopting the social customs, practices, and behaviors of the upper caste in order to advance in social position and hierarchy. Additionally, it involves changing their surname, getting married to girls from higher social classes, using Hindu scripts and Vedas, and changing their line of work. The social barriers relating to class discrimination and distinction in society are also being broken down by globalization, westernization, and urbanization.
Reproductive Challenges Encountered by Women with Differing Abilities
Authors: Malla Raju
Published: July 2024

This study aims to identify the reproductive challenges encountered through the women of differing abilities. Especially, what are the specific reproductive challenges encountered by women of differing abilities? How do societal attitudes and perceptions impact the reproductive health with differing abilities? What are the barriers to accessing reproductive healthcare services for women with disabilities? are the major questions which have been addressed and fulfilling through the following specific objectives such as to identify the specific reproductive challenges encountered by women with differing abilities, to analyze the impact of societal attitudes, and perceptions on the reproductive health with differing abilities and to assess the barriers that hinder access to reproductive healthcare services for women with disabilities. In this study researcher has employed a cross-sectional research design and adopted a quantitative methodology. Likewise, this study is based within Kirtipur Municipality, Kathmandu, Nepal. The study focused on women who had disabilities and registered in Kirtipur Municipality. Since the exact population for the study was unknown, a two-stage sampling approach was used. In the first stage, a list of women with disabilities registered in Kirtipur Municipality was purposively selected. In the second stage, 40 respondents, constituting 35.40% of the total list of 113 respondents, were randomly chosen using a simple random sampling method. Data collection primarily relied on the use of a questionnaire. Both structured and unstructured questionnaire formats were designed to gather quantitative information from the intended respondents.
The Constitutional Accommodation of Social Diversity in Nepal
Authors: Mallik Sabita Kumari
Published: July 2024

This article presents the status of social diversity in Nepal and its constitutional accommodation. It reflects the multi-cultural, multi-ethnic, multi-religious, multi-lingual society and the conflicts based on their diversity, which are the major issues of Nepalese society. In multi-structured society, the diverse groups create the conflict, socio-economic tensions, autonomy movements or struggle for separations. It has originated from the prehistoric age and gradually developed with the evolution of mankind. Nepal has been struggling with some level of inequality which is the great barrier in its social and economic development. This article tries to address the major areas of social diversities which create inequalities in Nepal and its constitutional accommodation. It also focuses on the process of inclusion under the constitution, so that the diversities should be accommodated. This paper is based on multicultural and liberal theory of political science research with normative approach. The paper also used the qualitative method and secondary sources to collect information. The major thrust of this paper is to discuss about the social diversities of Nepal and its accommodation under the constitution which makes it a multicultural, multilingual, multiethnic, multi-religious country. There are various groups which are in the state of political exclusion such as indigenous, women, madhesi, dalits (the lower caste), janajati and many others. It is necessary to have representation of all these groups not only in politics but also in socio-economic sector. This paper aims to analyze the constitutional accommodation which constitutes the society in a fabric of unity in diversity.
Corruption and its Implications for Politics in South Asian Countries
Authors: Thapa Santa Bahadur
Published: July 2024

This study measures corruption using survey data, newspaper reports, court records, anti-corruption agency records, and other sources. Corruption and problems with the government have been significant problems in South Asia since the early 1980s. The Corruption Perception Index (CPI) from Transparency International is recommended because it is a "robust" indicator that looks at many different ways to measure political corruption in each country. The root causes of corruption in South Asian countries, however, are a monopoly of government-controlled institutions, excessive regulations, convoluted tax and licencing systems, numerous government departments with opaque bureaucracies and discretionary powers, and a lack of transparency in laws and procedures. Tax evasion, which helps black money accumulate and lowers public morale, has a substantial negative impact on the economies and politics of South Asian nations. Since the 1980s, Pakistan, Bangladesh, India, and Bangladesh have all been officially charged with corruption. In addition, political rivals and the media frequently accuse the prime ministers of Sri Lanka and Nepal of corruption. In Bangladesh, Pakistan, and other South Asian countries, political bribery is widespread. In 2002, General Pervez Musharraf passed stringent election laws that forbade politicians convicted of a crime from seeking office. The rule's detractors believe that applying it would prevent the civilian community's two most influential political figures from challenging the military administration in elections later this year.
“छिमेकी” कथामा आदर्शोन्मुख यथार्थवाद {Aadshanmakh realism in the story of "Neighbourhood"}
Authors: एकनारायण EkNarayan पौड्याल Paudyal
Published: July 2024

यस अनुसन्धानात्मक लेखमा नेपाली साहित्यमा कथाकारका रूपमा परिचित गुरुप्रसाद मैनालीद्वारा लिखित छिमेकी कथाको आदर्शोन्मुख यथार्थवादका आधारमा अध्ययन गरिएको छ । प्रस्तुत कथा आदर्शोन्मुख यथार्थवादका दृष्टिले हेर्दा केकस्तो देखिन्छ भन्ने मुख्य समस्या र सोही समस्याको समाधानमा केन्द्रित छ । प्रस्तुत कथा अध्ययनका लागि प्राथमिक तथा द्वितीयक सामग्री प्रयोग गरिएको छ । चयनित कथा नासोमा सङ्गृहीत भएका कारण सो कथासङ्ग्रह प्राथमिक सामग्रीका रूपमा रहेको छ भने आदर्शोन्मुख यथार्थवाद र कथाकार गुरुप्रसाद मैनालीका सम्बन्धमा उल्लेख भएका सामग्री द्वितीयक स्रोतसामग्रीका रूपमा रहेका छन् । गुणात्मक प्रकृतिको यस अध्ययनमा व्याख्यात्मक र विश्लेषणात्मक विधि अवलम्बन गरिएको छ । कथाको अध्ययनपश्चात् प्रस्तुत कथा आदर्शोन्मुख यथार्थवादी मान्यताका आधारमा लेखिएको र यसले तत्कालीन नेपाली समाजको यथार्थ चित्र प्रस्तुत गर्नाका अतिरिक्त आदर्शवादी सन्देश दिएको ठहर गरिएको छ । सारतः विश्लेषित कथामा खासगरी पहाडिया ग्रामीण समाजको यथातथ्य चित्रण पाइनाका साथै सामाजिक यथार्थलाई आदर्शीकरण गरी देखाइएकाले कथा आदर्शोन्मुख यथार्थवादी बन्नपुगेको निष्कर्ष निकालिएको छ ।
{In this research article, the neighborhood story written by Guruprasad Mainali, who is known as a storyteller in Nepali literature, is studied based on idealistic realism. The presented story focuses on the main problem of what it looks like from the point of view of idealistic realism and the solution to the same problem. Primary and secondary materials have been used for the study of the presented story. Because the selected stories are collected in Naso, the collection of stories is the primary source material, while the material mentioned in relation to idealistic realism and storyteller Guru Prasad Mainali is the secondary source material. Descriptive and analytical methods have been adopted in this qualitative study. After studying the story, it has been concluded that the story was written on the basis of idealistic realist beliefs and it gave an idealistic message in addition to presenting the real picture of Nepali society at that time. Basically, in the analyzed story, especially the factual depiction of the hilly rural society is found, as well as the social reality is shown in an idealized manner, so it has been concluded that the story has become an idealistic realist.}
नेपाली रङ्गसंस्थाको अध्ययन {A study of Nepali colors}
Authors: Ashok अशोक Thapa थापा
Published: July 2024

प्रस्तुत लेखमा नाटक मञ्चन गरिने स्थानविशेषलाई रङ्गमञ्च भनिने कुरा उल्लेख गर्दै नेपालमा रङ्गमञ्चको विकाससँगै रङ्गमञ्च सम्बद्ध संघसंस्थाको विकास हुन थालेको जानकारी दिइएको छ ।
नेपालमा रङ्गसंस्थाको क्रमिक विकासको परम्पराको पनि यहाँ चर्चा गरिएको छ । अनौपचारिक रूपमा विकास भएको नेपाली रङ्गमञ्चीय गतिविधि मुकुन्द इन्दिरा (सं. १९९४) नाटकको मञ्चन भएसँगै आधुनिक कालमा प्रवेश गरेको कुरा यहाँ उल्लेख गरिएको छ । आगमन र निगमन दुवै शोधविधिको प्रयोग गरिएको यस लेखमा नेपाली रङ्गमञ्च सम्बद्ध संस्थाको सर्वेक्षण गरिएको छ । सामग्रीसङ्कलनका लागि पुस्तकालय कार्यलाई मूल आधार मानिएको यस लेखमा विषयसम्बद्ध भएर अतीतमा भएगरेका पूर्वकार्यको अवलोकन र समीक्षा पनि गरिएको छ । प्रस्तुत लेखमा नेपालमा रहेका रङ्गसंस्थाको सर्वेक्षण गरी तिनीहरूको अवस्था र नेपाली रङ्गमञ्चमा त्यसको उपादेयता अनि प्राप्तिका विषयमा पनि चर्चा गरिएको छ । यस लेखमा नेपाली रङ्गमञ्चको इतिहासको सङ्क्षिप्त अनुरेखाङ्कन गरिएकाले रङ्गक्षेत्रको अध्ययन गर्न चाहने अनुसन्धातालाई भविष्यमा एक प्रभावकारी स्रोतसामग्री हुने निक्र्यौल निकालिएको छ । मुकुन्द इन्दिराको मञ्चनपछि नेपाली रङ्गमञ्चमा आधुनिकताको स्थापना भएको कुरा उल्लेख गर्दै नेपालमा रङ्गमञ्चीय संस्थाको स्थापना चालीसको दशकपछि अधिक भएको छ भन्ने निचोड निकालिएको छ । यसैगरी प्रस्तुत लेखमा नेपाली
रङ्गमञ्चमा हिजोदेखि आजसम्म मञ्चित नाटकको स्थिति र ती नाटकका प्रवृत्तिको विवेचना गरिएको छ । प्रस्तुत लेखमा नेपाली रङ्गमञ्चको इतिहासमा रङ्गसंस्थाको स्थापना र विकास हुने क्रम वृद्धि हुँदै गएको निचोड निकालिएको छ ।
(In the presented article, it has been mentioned that the special place where the drama is staged is called Rangamancha, along with the development of Rangamancha in Nepal, the development of organizations related to Rangamancha has been given.
The tradition of gradual development of color organization in Nepal is also discussed here. It is mentioned here that the informally developed Nepali theater activity entered the modern period with the staging of the play Mukund Indira (ed. 1994). In this article, which uses both arrival and incorporation research methods, a survey of Nepali Ranga Mancha related organizations has been conducted. In this article, which considers the library work as the basic basis for the collection of materials, the previous work done in the past has been observed and reviewed in connection with the subject. In the present article, a survey of theater institutions in Nepal has been conducted and their condition and their applicability and success in the Nepali theater stage have also been discussed. In this article, as the history of Nepali theater is briefly outlined, it is expected to be an effective resource for researchers who want to study the theater. After the staging of Mukund Indira, modernity was established in the Nepali stage, and it has been concluded that the establishment of theater institutions in Nepal has increased after the forties. Similarly, Nepali in the presented article
The status of dramas staged on the stage from yesterday to today and the trends of those dramas have been discussed. In the presented article, the establishment and development of theater organizations in the history of Nepali theater has been summarized.}
The Existence of Supreme Court Regulation of the Republic of Indonesia No. 02 of 2012 concerning the Adjustment of the Limitation of Minor Offences and the Amount of Fines in the Criminal Code Towards the Law Enforcement Process
Authors: Azmi M Hijratul , Amiruddin  , Pancaningrum Rina Khairani
Published: July 2024

This research aims to analyze the position of Supreme Court Regulation No. 02 of 2012 in determining minor offenses in the criminal law enforcement process and to analyze the binding force of Supreme Court Regulation No. 02 of 2012 in law enforcement practice. The research method used is normative legal research with statutory and conceptual approaches. The research results show: 1) Supreme Court Regulation No. 2 of 2012 concerning the Adjustment of the Limitation of Minor Offences and the Amount of Fines in the Criminal Code is not included in the hierarchy of Laws and Regulations, but the Supreme Court Regulation is recognized as long as it is ordered by higher Laws and Regulations or formed based on authority, so the position of this Supreme Court Regulation is not equal or below the Law; 2) The Supreme Court Regulation is binding on the Police, Attorney General's Office, and Courts due to the signing of a Joint Memorandum of Agreement with the Minister of Law and Human Rights of the Republic of Indonesia, the Attorney General of the Republic of Indonesia and the National Police of the Republic of Indonesia.
A Correlational Study between the level of academic performance and the level of academic stress among Young Adults
Authors: Sahu Priyanka , Kumar Mahendra , Sahu Diksha , Chauhan Swarna
Published: July 2024

Introduction: Stress may decrease cognitive capacities and learning in young adults , affecting academic performance. The primary aim of the research was to examine the correlation between academic stress and academic performance. Method: The samples (male 50, female 50, aged 17-23 years) were taken from different universities in India. Academic stress was measured by the (ASS) Academic stress scale and academic performance was measured by Birchmeier, C. et al., from Saginaw Valley State University (APS) Academic performance scale. The data was analysed using SPSS (version 16). Result: Research indicates a significant negative association (r = -0.60, p < 0.001) between academic stress and performance, with higher stress levels resulting in decreased performance. Multiple regression analysis shows that academic stress significantly impacts academic performance (β = -0.45, p < 0.001). Students with high stress performed less well academically compared to those with low or moderate stress (F (2, 97) = 12.34, p < 0.001). Female students reported much greater academic stress across every dimension than male students. For AST, females (M = 46.16) had significantly higher stress levels than men (M = 35.26); t (98) = 3.75, p =.001. Conclusion: The findings indicate that students are likely to achieve higher academic performance when they experience lower levels of academic stress.
The Effect of Using Anticipation Guide Strategy on Studentsâ€™ Reading Comprehension at Politeknik Bina Husada Kendari
Authors: Azwan Hepriansyah
Published: July 2024

This study was an experimental study conducted at the Poltiteknik Bina Husada Kendari registered in the academic year 2022/2023. The objective of this study was to find out whether the effect of the Anticipation Guide Strategy significantly affects students’ reading comprehension. The sample for this study was 2 classes (60 students) from 4 classes (110 students) in the Dental Health Study Program at the Poltiteknik Bina Husada Kendari. The instrument for collecting data was a reading comprehension narrative text in the form of a multiple-choice test, that consisted of 30 items. Pre-test and post-tests were conducted in both experimental and control classes. To analyze the data was used Independent Sample t-Test. After analyzing the data, the research got; (1) the students’ achievement in reading comprehension taught by conventional method had Mean = 61.333 and Standard Deviation = 9.1852. (2) the student’s achievement in reading comprehension taught by the anticipation guide strategy had a Mean = 85.167 and a Standard Deviation of 6.3631. It can be concluded that there is a difference in the average student learning outcomes between the control group and the experimental group. (3) The result of the Independent Sample t-test showed that the significance value (Sig.) was 0.000 smaller than the probability of 0.05. That shows if H0 is rejected and Ha is accepted. This means that there was a significant effect of using the anticipation guide strategy on students’ reading comprehension at Politeknik Bina Husada Kendari.
Improving Letter Writing Ability Through Demonstration Methods Assisted by Wipe Clean Worksheet Media in Group B Children RAM NU East Rowokembu
Authors: Sa'adah Sa'adah
Published: July 2024

In writing learning process at RAM NU East Rowokembu, there are difficulties because students often need to remember the shape of the letters of the alphabet, so writing the letters is unclear. This condition allowed the writer to conduct classroom action research in two cycles. This research aims to improve the ability to write letters using a demonstration method assisted by wipe-clean worksheet media for children in group B RAM NU East Rowokembu. The research methods used are quantitative and qualitative. The subjects of this research were ten children in class B1 RAM NU East Rowokembu. Observation, interviews and documentation were used as data collection techniques. The data acquisition tool uses an observation sheet. Data analysis uses qualitative and quantitative descriptive. It is said that the capacity to write letters is successful if the percentage reaches 75 -100% with the criteria of developing according to expectations (BSH). The research results showed that the ability to write letters in the pre-action stage reached an average percentage value of 10%. Then improvements were made in cycle I, which increased slightly with an average percentage of 30%. After the first cycle of intervention succeeded in influencing the ability to write letters, the level of success had yet to be achieved, so the next cycle needed to be carried out. The results of cycle II showed that the ability to write letters reached the final level of 80% according to the BSH criteria. So, letter writing skills increase in class B1 RAM NU East Rowokembu
U.S. Program on Materials Technology for USC Power Plants
Authors: Viswanathan R. , Henry Jeff. F. , Tanzosh Jim , Stanko Greg , Shingledecker J. , Vitalis Brian
Published: July 2024

The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). The project goal initially was to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760°C (1400°F)/35 MPa (5000 psi), although this goal for the main steam temperature had to be revised down to 732°C(1350°F), based on a preliminary assessment of material capabilities. The project is intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620°C (1150°F) and nickel-based alloys suitable up to 700°C (1300°F). In this project, the maximum temperature capabilities of these and other available high- temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This paper provides a status report on the progress to date achieved in this project.
The Development of Inconel Alloy 740 for use as Superheater Tubing in Coal Fired Ultra Supercritical Boilers
Authors: Smith Gaylord D. , Baker Brian A. , Shoemaker Lewis E.
Published: July 2024

Utilities worldwide are facing increased demand for additional electricity, reduced plant emissions and greater efficiency. Part of the solution is achieved by increasing boiler temperature, pressure and coal ash corrosion resistance of the materials of boiler construction. In this paper, a new nickel-base tube alloy, INCONEL alloy 740, meeting this challenge is characterized with emphasis on mechanical properties, coal ash and steam corrosion resistance as well as weldability. Microstructural stability as a function of temperature and time is addressed as well as some of the early methodology employed to arrive at the current chemical composition. Brief mention is made of certain current and future alloy characterization efforts and potential environmental benefits to be expected should the boiler technology utilizing INCONEL alloy 740 be adopted.
Use of Surface Modification of Alloys for Ultrasupercritical Coal-fired Boilers
Authors: Goodstine Stephen L. , Nava Juan C.
Published: July 2024

Ultrasupercritical (USC) coal-fired boilers, currently under study, will be required to utilize a variety of new, high strength alloys. These alloys will have improved mechanical properties compared with more traditional boiler materials and so will be suitable for operation in higher temperature service. However, environmental resistance, i.e. internal steam oxidation and external coal-ash corrosion, will be a factor limiting application of some materials under consideration. In those cases, the operating range of lower-cost alloys can be significantly extended by the use of surface modification techniques. This paper will review potential surface modification techniques and report on early test results of some laboratory evaluations.
Modification of Ni-Fe Base Superalloy for Steam Turbine Applications
Authors: Imano S. , Doi H. , Saitoh E. , Iijima K.
Published: July 2024

To improve microstructure stability at temperature up to 700°C and avoid segregation of Nb during melting processes, we modified the chemical composition of conventional Ni-Fe base super alloy(Ni-36Fe-16Cr-3Nb-1.7Ti-0.3Al:Alloy706). It is known that Alloy706 is strengthened by γ'(Ni3Al) phase and γ”(Ni3Nb) phase. But these phases are unstable at high temperature and transform into Nb rich δ or η) phase after long-term exposure to elevated temperature. Therefore modified alloy contains lower Nb and higher Al than those of Alloy706, and it is mainly strengthened by γ’(Ni3Al) phase. In fact we could not find δ or η phase in the modified alloy after creep and aging at 700 °C. Tensile strengths of the modified alloy at temperature from room temperature to 700 °C were almost same as those of Alloy706. Yield strength of modified alloy at room temperature was slightly lower than that of Alloy706, but equivalent to that of Alloy706 at higher temperatures. Tensile and yield strengths of the modified alloy at temperature from room temperature to 700 °C were higher than those of Alloy706 after aging at 700 °C. In this paper, we discuss effects of Nb and Al on mechanical properties and microstructure at elevated temperature up to 700 °C, using mechanical testing, TEM observations and thermodynamics calculation results. And we show advantages of the microstructure stabilized Ni-Fe base superalloy(FENIX-700), which is a candidate material for 700 °C class USC steam turbine rotor.
The Small Punch Test Method: Results from a European Creep Testing Round Robin
Authors: Bicego V. , Rantala J.H. , Klaput J. , Stratford G.C. , Di Persio F. , Hurst R.C.
Published: July 2024

The small punch (SP) test technique can generate tensile, toughness, and creep strength data from very small specimens, enabling nondestructive sampling from large components. This has accelerated industry interest in SP, particularly in the energy sector. A round-robin for the SP creep test was organized within the EPERC network on a 1CrMoV rotor steel, primarily to contribute to harmonizing the test procedure for this emerging method. This presentation analyzes the SP creep test results performed at several temperatures and one load level to assess their inter-comparability and interpret the results concerning conventional uniaxial creep tests. The SP loading geometry appeared to be a key parameter in evaluating the SP results, particularly for correlation with uniaxial creep behavior. A standardization initiative for the SP test method, including creep as well as low-temperature testing for determining tensile and toughness properties of metallic materials, has recently started via a CEN Workshop.
Long-Term Mechanical Properties of Dissimilar Welds Between P91 Grade and Low-Alloyed Steels
Authors: Prchlik L. , Folkova E. , Hranek P.
Published: July 2024

Dissimilar joints between modern 10% chromium steels and low-alloy steels are unavoidable in new installations or upgrades of steam turbine components. Welds between 10CrMo9-10 (P22) and X10CrMoVNb9-1 (P91) steel pipes are often required. This paper studies this heterogeneous weld from a steam turbine manufacturer's practical perspective. Two types of filler materials were used: P22- and P91-based weld metals. The integrity and mechanical properties of the prepared heterogeneous welds were evaluated according to the welding standard EN 288-3. Both approaches yielded satisfactory results. Additionally, creep rupture strength was evaluated. The creep rupture strength of both joints fell within the -20% scatter band of the P22 base material's creep rupture strength. The weld design with P91 filler material appeared to slightly outperform the P22-based approach for longer exposure times.
Alternative Filler Materials for Dissimilar Metal Welds Involving P91 Materials
Authors: Coleman K. , Gandy D.
Published: July 2024

In the late 1980s, the domestic utility industry experienced failures in dissimilar metal welds (DMWs) between low-alloy ferritic tubing and austenitic tubing in superheaters and reheaters. Extensive research by EPRI found that nickel-based filler metals provided significant service life improvements over 309 stainless steel filler metals. Improved joint geometries and additional weld metal reinforcement were determined to extend service life further. A new nickel-based filler metal was also developed, exhibiting thermal expansion properties similar to the low-alloy base metal and a low chromium content that would result in a smaller carbon-depleted zone than currently available fillers. However, this new filler metal was never commercialized due to a tendency for microfissuring, resulting in less than desired service life. This paper discusses further investigation into the filler metal microfissuring issue and examines long-term testing to determine the filler's suitability for high-temperature applications.
Materials for Corrosion and Erosion Protection in Low NOx Power Boiler Super Heater Tubes
Authors: Kiser Samual D. , Faws P.E. , Orsini Tino
Published: July 2024

Tests show that Inconel Filler Metal 72 overlay and/or Incoclad alloys 671/800HT are two material solutions that will provide adequate corrosion and erosion protection for superheater and reheater tubes in low-NOx boilers. This paper gives an overview of the corrosion issues involved in these applications and presents test data for these materials.
The Fracture Behaviors of the Welded Joints in P92, P122 and P23 Pipe Steels for Fossil Power Plants
Authors: Ryu S. H. , Lee Y. S. , Kong B. O. , Kim J. T. , Baek J. W. , Nam S. W. , Kim B. J. , Lim B. S.
Published: July 2024

This paper reports on a study that investigated how low cycle fatigue (LCF) and fatigue crack propagation (FCG) properties of P92, P122, and P23 steels vary between 600°C and 700°C depending on the location relative to a cross weld. Microstructure analysis was also performed on fractured specimens. Due to its higher yield strength, P122 exhibited the best continuous LCF life. However, creep-fatigue interaction (CFI) in the weld heat-affected zone (HAZ) of P122 and P23 steels significantly reduced their lifespans compared to continuous LCF tests. This reduction is attributed to the effect of weld thermal cycles on fine precipitates. FCG tests revealed that the base metal consistently outperformed the HAZ in all tested steels and temperatures. P92 and P122 showed similar FCG rates except for P92's behavior at 600°C, which resembled P23. In both steels, the HAZ exhibited faster FCG rates at 600°C and 700°C compared to the base metal, particularly at lower stress intensity factor ranges (ΔK). Within the HAZ, the region 1 mm from the fusion line displayed the slowest FCG rates, followed by the base metal, while the fusion line and the region 2 mm from it showed the fastest. Fracture surfaces near the fusion line displayed cleavage-like features, while the region 1 mm away exhibited features associated with higher crack growth resistance.
Weldability Evaluation of Martensitic Heat Resisting Chromium Steels with Tungsten Additions and Properties of Welded Joints
Authors: Brózda J. , Pasternak J.
Published: July 2024

Short characteristics of the out-of-date Polish power generation system are given, which shows that in the near future there will be a shortage of electrical energy and the necessity to build supercritical power units. A lignite-fired boiler will be build at the RAFAKO Boiler Plant. Supercritical operating parameters require new creep resisting steels to be applied for the boiler and pipe systems. Therefore at the Institute of Welding weldability examinations have been performed on selected Cr-W heat resisting steels. Welding thermal cycles have been simulated on steels: HCM2S (T23/P23), T92/P92, E911 and HCM12A. The influence of t8/5 cooling times on Charpy V notch toughness, HV10 hardness and microstructure of simulated HAZ's is presented in the form of graphs and prints of microstructures. By means of simulation technique the susceptibility to reheat cracking of those steels has been evaluated. At REMAK- Opole (Enterprise for the Modernisation of Power Installations) and RAFAKO tube and pipe test joints were welded, to select proper fabrication conditions. Mechanical properties of the welded test joints, KV notch toughness of weld metals and HAZ’s and microstructures were examined and are presented.
Thermodynamic Databases: Useful Tools in the Development of Advanced Materials
Authors: Zhang F. , Chen S.-L. , Xie F.-Y. , Chang Y. A. , Oates W. A. , Schmid-Fetzer R.
Published: July 2024

Materials are developed and improved by adjusting both the alloy chemistry and the processing conditions to achieve desired microstructures and properties. Traditionally, these improvements have been made by a slow and labor-intensive series of experiments. But it is now possible to replace this expensive trial and error process by carrying out only a few ‘key’ experiments in conjunction with thermodynamic calculations. These calculations are powerful tools for alloy design, enabling improvement in the selection of alloy chemistry and the parameters used for fabrication steps such as heat treatments. In order to have the utmost confidence in the results obtained from the calculations, it is essential to have high quality thermodynamic databases. Such databases can be used not only in phase equilibrium calculations but also as the critical input for further kinetic simulations. In the present paper, we present our work on the development of reliable thermodynamic databases for nickel-based superalloys and iron alloys. We first briefly describe the methodology of developing these databases and then discuss some specific examples using the databases. With the aid of these examples, the usefulness of thermodynamic databases in aiding the development of advanced materials is discussed.
A Comprehensive Approach to the Development and Improvement of 9-12% Cr Steels: Report, Status, and Outlook
Authors: Cerjak H. , Dimmler G. , Hofer P. , Kozeschnik E. , Letofsky E. , Pein C. , Rajek J. , Schaffernak B. , Sonderegger B. , Weinert P.
Published: July 2024

The Institute of Materials Science, Welding and Forming (IWS) conducts research activities on ferritic/martensitic 9-12% Cr steels through an interconnected network of projects. These projects focus on mechanical properties of base and weld metals, microstructural characterization of creep and damage kinetics, weldability, microstructure analysis during creep, modeling of precipitation and coarsening kinetics, and deformation behavior under creep loading. The individual projects are briefly described, outlining the conceptual approach towards quantitatively describing the creep behavior of 9-12% Cr steels. The research efforts aim to comprehensively understand and model the creep performance of these advanced steel grades by investigating their microstructural evolution, damage mechanisms, precipitation kinetics, and deformation characteristics under creep conditions. The integrated projects examine both base metals and welded joints, providing insights into material properties, weldability, and microstructure-property relationships critical for their application in high-temperature components.
Creep Strength Evaluation of Serviced and Rejuvenated T91 using the Stress Relaxation Method
Authors: Woodford David A. , Swindeman Robert W.
Published: July 2024

High precision stress relaxation tests (SRT) at temperatures between 550C and 700C were performed on serviced and reheat treated T91, 9%Cr steel. The service exposure was 116,000 hours at steam temperatures to 550C. Constant displacement rate (CDR) tests were also run at 600C on notched specimens for the two conditions. Specimens, heat treated after service, were stronger at the lower test temperatures in terms of both tensile strength and creep strength. This difference was reflected in the CDR results, which also suggested a lower fracture resistance in the heat treated condition. Thus, service exposure appears to have softened the alloy and enhanced its resistance to fracture, with no evidence of embrittling reactions. Based on the analysis of the SRT tests, projections were made of the times to 1% creep and the times to rupture as well as direct comparisons with minimum creep rate data'. When plotted on the basis of a Larson- Miller parameter (C=30), the calculated values compared well with actual long time rupture testing for exposed and re-heat treated specimens, and generally showed higher precision. The longest test time was about eighteen months for the stress rupture data compared with the use of one machine for a few weeks for the SRT data. The latter actually covered a far greater range of creep rates and projected lives. The SRT test is especially consistent at higher parameter values, i.e., higher temperatures and/or lower stresses. This method of accelerated testing is now being applied to a wide range of alloys for fossil power plants for composition and process optimization, design analysis, and life assessment.
Creep Response of Advanced Martensitic Steels to Stress and Temperature Changes after Long Times
Authors: Swindeman M. J. , Swindeman R. W.
Published: July 2024

Significant developments have been made in recent years in the description of creep as a damage process. Advanced martensitic steels that expend over half their lives in the tertiary creep stage have been the focus of attention since their use temperatures are being extended to higher temperatures. Data available for assessing the predictability of the damage models are somewhat scarce since long-time exposure testing has generally been for constant temperature and load conditions. In this work, data are reviewed from relatively long-time tests that involved temperature and stress changes. The prediction of several damage models are compared to material behavior. Most of the comparisons are for 9Cr-1Mo-V steel in the temperature range of 538 to 649 C and for times in the range of 10,000 to 80,000 hours.
Aluminum Nitride Precipitation in Low Strength Grade 91 Power Plant Steels
Authors: Brett S. J. , Bates J. S. , Thomson R. C.
Published: July 2024

This paper investigates the cause of premature failures in certain Grade 91 steel components used in UK power plants. The failures were linked to both low material hardness and specific chemical compositions that fell within ASTM specifications but had a low nitrogen-to-aluminum ratio (N:Al). The investigators examined eight material batches, including those involved in failures, new stock, and in-service components with similar properties. Testing confirmed these materials had lower creep resistance compared to standard Grade 91 steel. Microscopic analysis revealed the presence of large aluminum nitride precipitates, which limited the formation of beneficial vanadium nitride precipitates, leading to reduced creep strength. These findings suggest that even within the ASTM specification limits, a low N:Al ratio can negatively impact the performance of Grade 91 steel.
The Effects of Carbon and Austenite Stabilizing Elements (Co, Cu, Ni and Mn) on the Microstructural Changes and the Creep Rupture Strength in 9-12 % Cr Ferritic Heat Resistant Steels
Authors: Ryu S. H. , Kim M. S. , Lee Y. S. , Kim J. T. , Yu J. , Lee B. J.
Published: July 2024

This study examines the influence of carbon and austenite stabilizing elements (Ni, Mn, Co, Cu) on Laves phase precipitation, Fe2W formation, and creep rupture strength (CRS) in 9-12% Cr steels at 600-700°C. Nickel and manganese had minimal impact on Laves phase and coarse carbide formation up to 1% content. While cobalt increased Laves phase fraction at 650°C, it did not improve long-term CRS and even caused a rapid decrease in short-term CRS. Copper, on the other hand, promoted the precipitation of fine Cu-rich particles that acted as nucleation sites for Laves phase and M23C6 carbide. This resulted in a different needle-like Laves phase morphology compared to the globular type observed in nickel and cobalt alloys, leading to improved CRS in the copper alloy. Increasing carbon content from 0.1% to 0.2% effectively suppressed Laves phase formation, as confirmed by Thermo-Calc calculations. Notably, for cobalt alloys with higher tungsten content, higher carbon content (0.09% to 0.19%) improved CRS at 650°C, whereas the opposite effect was observed in nickel and nickel-manganese alloys. Copper alloys maintained improving CRS trends even with increased carbon, leading to the overall best CRS performance among the tested alloys with 0.2% carbon.
A Study on Digital Media Communication Channels for Narrative Shaping
Authors: Zhai Yao ,   Nanjing Normal University
Published: July 2024

The research was conducted to address the gaps in knowledge related to narrative shaping by using digital media platforms. This research aimed to measure the impact of mobile phone applications, website forums, content-boosting campaigns, and digital community groups on information dissemination in China. The study used a five-point Likert scale to collect the data. A convenience sampling approach was used to collect data, and a sample of 171 individuals was considered. The findings of this study were analyzed using RStudio and R language. The study empirically discussed the relationship between mobile phone applications, website forums, content-boosting campaigns, and digital community groups regarding information dissemination in China. The findings of this research enriched the literature because loops in the literature were previously found. The study further recommends practical recommendations to advance narrative shaping in China with the help of digital platforms.
Role of Artificial Intelligence Information in Product Selection for Chinese Consumers
Authors: Liu Pengyu ,   Guangzhou Academy of Fine Arts, Zhang Hui ,   Heilongjiang University
Published: July 2024

A significant amount of AI information has been incorporated into the process of selecting products that offer consumers more precise and individualized services. Conducting research on the various functional experiences of AI for consumers is crucial in order to enhance the current implementation of AI information in China. The purposive sampling techniques is used to target the desired consumer in China. In order to assist consumers in selecting the desired product, this study categorizes AI-related information into three distinct dimensions: insight, interaction, and accuracy. The mediating variable is defined as the consideration set. This study employs primary methods to examine the impact of three components of AI information in order to investigate the internal mechanism that influences consumers' product selection. The findings shows that AI insight is the strongest predictor of consideration set followed by accuracy and interaction is also significant. This study is significant for e-commerce, consumer and market.
On the issue of multi-level educational tasks in mathematics for an engineering and mathematics class
Authors: Sapegin Vladimir Andreevich
Published: July 2024

The chapter discusses multi-level math assignments for an engineering and mathematics class. The requirements for mathematical questions, mathematical dictation, mathematical exercises and educational tasks for students of three level groups (proposed by the author) are highlighted and justified. The training tasks on the topic «Irrational equations with parameters» are given in accordance with the presented requirements.