bluuebunny/crossref_metadata_2025 huggingface dataset:
Pedagogical Challenges and Opportunities during Covid-19 Pandemic: Perspectives from the Pre-Service and High School Teachers
Authors:   Faculty Member, College of Education, Culture, and Arts, St. Paul University Surigao, Surigao City, Philippines, C. Tagalog Mcbon Lyle , P. Larong Flora Loyda ,   Faculty Member, College of Education, Culture, and Arts, St. Paul University Surigao, Surigao City, Philippines, E. Limlingan Ricky Boy ,   Faculty Member, College of Education, Culture, and Arts, St. Paul University Surigao, Surigao City, Philippines, Sumampong Alvin J. ,   Alumni, College of Education, Culture, and Arts, St. Paul University Surigao, Surigao City, Philippines, Saavedra Maricar M. ,   Alumni, College of Education, Culture, and Arts, St. Paul University Surigao, Surigao City, Philippines, Chua Liza L. ,   Alumni, College of Education, Culture, and Arts, St. Paul University Surigao, Surigao City, Philippines
Published: February 2023

This study aimed to determine the pedagogical challenges and opportunities of the Pre-Service and high school teachers in the new normal education. The sample size was determined using the slovins formula and 13 pre-service teachers, and 26 High School Teachers were the participants. Descriptive and inferential were used. Findings revealed that most of the respondents were 21-26 years old, female, high school teachers, and situated mostly in urban areas. The conduct of online classes was the major challenge faced by both pre-service and high school teachers for they used to conduct classroom teaching for many years. The online teaching-learning modality was successfully implemented to practice teaching as a mission to facilitate students learning through various online strategies during the COVID-19 pandemic. Age, sex, type of respondents, and locality did not show a significant degree of variance in the extent of the pedagogical challenges and opportunities they encountered. The locality has a significant degree of variance in terms of teaching-learning engagement and opportunities for teaching-learning platforms. Hence, seminars and workshops on online pedagogies and online assessment tools strategies to facilitate online teaching more engaging was recommended.
Correlation Between Tirads Classification Ultrasonography and Cytopathological Findings of Thyroid Nodules: The Wahidin Sudirohusodo Hospital Experience
Authors:   Faculty of Medicine, Hasanuddin University, Indonesia, Cahyani Venna Regita , Juanita Juanita ,   Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Indonesia & Lab Anatomical Pathology, Wahidin Sudirohusodo Hospital, Makassar, Indonesia., Yamin Amalia ,   Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Indonesia & Lab Anatomical Pathology, Wahidin Sudirohusodo Hospital, Makassar, Indonesia., Miskad Upik A. ,   Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Indonesia
Published: February 2023

Background: Thyroid nodule is one of the most common endocrine system diseases in the world with the increasing number of incidences every year. A thyroid nodule is commonly detected by ultrasonography (USG), in which ultrasonography is the main modality of non-invasive thyroid nodule examination that is accessible, and inexpensive. Aim: The present study aims to improve the clinical practice and management of thyroid lesion by establishing correlations between TIRADS classification ultrasonography (USG) with cytopathological findings in thyroid nodule patients. Methods: Research method that is used is anobservational analytics with cross-sectional approach. The sample of this research is taken by a consecutive sampling method from medical records of thyroid nodule patients in Wahidin Sudirohusodo Hospital year 2021. Statistic test that is used in this research is spearman test. Data analyzes uses SPSS 27.0. software. Results: In this research, 51 research samples analyzed by spearman statistic test shows a significant correlation between TIRADS classification ultrasonography (USG) and cytopathological findings (p = 0,035). Conclusion: TIRADS classification ultrasonography (USG) has a significant correlation with cytopathological findings in thyroid nodule patients at Wahidin Sudirohusodo Hospital year 2021
The Effect of Whatsapp-Based Blended Problem-Based Learning on Students' Scientific Argument Ability in the Concept of Viruses
Authors:   Universitas Siliwangi, Jalan Siliwangi No.24 Tasikmalaya Indonesia, Mustofa Romy Faisal , Luthfiani Ninda ,   Biology Education Study Program, Jalan Siliwangi No. 24 Tasikmalaya Indonesia, Diella Dea ,   Universitas Siliwangi, Jalan Siliwangi No.24 Tasikmalaya Indonesia
Published: February 2023

This study aims to determine the effect of Whats App-based blended problem-based learning on students' scientific argumentation skills on the concept of a virus in class X MIPA Madrasah Aliyah Negeri Tasikmalaya Indonesia. The research method used is a quasi-experimental method using a posttest only control design. The population in this study was class X MIPA as many as 202 people. Samples were taken by non-probability sampling in the form of purposive sampling. The sample used is MIPA 5 and X MIPA 6 classes at Madrasah Aliyah Negeri Tasikmalaya Indonesia as many as 61 students. With MIPA 6 class as many as 30 students as the experimental class and X MIPA 5 as many as 31 students as the control class. Data collection was done by giving 7 questions of scientific argumentation. The data analysis technique used was t independent with a significance value (0.0001). The results showed that there was an effect of WhatsApp-based blended problem-based learning on the ability to argue scientifically. Other findings show that the average scientific argumentation ability of students is based on its components, namely claim (2,224), evidence (1,825) and reasoning (0,378).
Analisis Kinerja Sistem Penilaian Lomba Tari Bali Berbasis Mobile
Authors: Supartha I Kadek Dwi Gandika , Wijaya I Putu Agus Sukanta
Published: February 2023

Balinese dance is a type of dance originating from Bali that has existed for a long time and has been passed down from generation to generation by Balinese people. Balinese dance has 3 kinds of categories, namely Wali Dance (sacred), Bebali Dance and Balih-Balihan Dance (Profane). Balinese dances that are sacred are usually performed on certain days or during religious ceremonies, while profane dances are usually performed for entertainment. In Bali, many types of Balinese dances are contested, such as Barong Dance, Jauk Manis Dance, Jauk Keras Dance, Baris Dance and so on. In this study, the design and development of a Balinese dance competition assessment application was carried out which aims to facilitate the performance of the competition organizing committee and the judges during the assessment and recording of the participants' scores after the competition is held and can display the values transparently to the public. Tests show that when the application is run, it gets a value of 312.3999996185303 on the application and a value of 312.4 in the manual assessment process. The dance assessment application and manual assessment have almost the same value with a percentage accuracy of 99.9%.
Limiting Heating & Cooling Peak Loads for Net Zero Carbon Buildings
Authors:   Associate, Hoare Lea Consulting Engineers, North Offices, UK, Elsarrag Esam , Nuttall Jon ,   Director, Hoare Lea Consulting Engineers, North Offices, UK
Published: February 2023

Limiting peak heating and cooling loads is an important factor in net zero carbon building in relation to renewable energy implementation, load shifting, etc. Passive and active measures are necessary to limit or shift peak loads in net zero carbon buildings. With the increasing demand for more sustainable and energy-efficient buildings and services to combat climate change, weather data has now become an essential component of virtually every new building design and major refurbishment. In this study, dynamic simulation is used to predict the peak heating and cooling loads for an office building to understand the impact of different load estimate parameters on heating and cooling loads. This paper will discuss the impact of using different weather files, heat gains and shading on the peak loads. It also provided guidance to minimise heat peak loads spikes.
An analysis of the titles of works of art in English from the perspective of linguistic pragmatics and linguistic culture
Authors: Akhmedov Umid
Published: February 2023

In this article, the features of preserving the names of works of art in English from the point of view of linguistic pragmatics and linguocultural science are explained. In addition, attempts are made to observe and research the local linguistic cultures of the science in the quality of anthroponyms and expressions, similes and metaphors in the object of the Uzbek language. The burden of the nomination process depends on the semantic requirements of the interpretation in linguistics. The linguistic pragmatics and linguocultural and logical changes of the names of works of art in English are similar, some of them are not only in terms of content but also about the production and research of correct structures.
Linguoculturological and linguopragmatic characteristics of irony
Authors: Parmonov Alisher
Published: February 2023

Linguoculturology and linguopragmatics are new and most commonly learned spheres of linguistics. Researching linguistics linguculturologically shows that it demonstrates culture and linguistics. The article illustrates irony, its linguoculturologik and linguopragmatic features in discourse.
O‘zbek xalq ertaklarining bola tarbiyasidagi o‘rni
Authors: Choriyeva Nasiba
Published: February 2023

Bugungi kunda maktabgacha yoshdagi bolalarni xalqning boy, milliy, madaniy-tarixiy merosi va ma’naviy-axloqiy jihatdan tarbiyalash, maktabgacha ta’lim muassasalari oldiga qo‘yilgan dolzarb vazifalardan biri hisoblanadi.
Evaluation Of Random Forest Model on Influenza Like Illness ILI Surveillance Based on Patients Attending Fever OPD During COVID 19 Pandemic at Tertiary Care Hospital In Raigad District Maharashtra India
Authors: Mr Raut K N, Dr Tayade A Y
Published: February 2023

Introduction: The machine learning and artificial intelligence tools, party and random forest can be used to evaluate surveillance data for better outcomes. The primary objective of the study was to evaluate the utility and reliability of machine learning and artificial intelligence model primary data for the Influenzas Like illness (ILI) Surveillance of patients attending fever OPD in a tertiary care hospital during covid 19 pandemic. The secondary objective was to estimate model statistics to measure the effect of parameters.

Methodology: This is a secondary data analysis study based on surveillance data in the tertiary care hospital attached to medical college. The data of 3723 cases was collected by Surveillance team for Influenzas Like Illness (ILI) under Department of Community Medicine in Fever OPD during covid pandemic from 23 March 2020 to 30 June 2020. Data consisted (11) variables. Data was analysed using R Software (4.2.2). Machine learning (ML) and Artificial Intelligence tool party and random forest were applied.

Results: The random forest model performed better than Party model with model accuracy of 0.9557, AUC of random forest model were 87.4% (sensitivity 0.9533, specificity 0.9685), 89.7% (sensitivity 0.9059, specificity 0.9957) and 88.3% (Sensitivity 0.965, Specificity 0.9527) for confirmed, probable and suspected with different cut-offs. The model found Severity of Patient (Mild, Moderate, Severe), the day of Fever OPD Visit, nature of illness (is asymptomatic?) and age of patient as the most significant factors in decreasing order by mean decrease in Accuracy while the Severity of Patient (Mild, Moderate, Severe), the day of Fever OPD Visit, age of patient and number of symptomatic Complaint (NOC) were found the most significant factors in decreasing order by mean decrease in Gini to predict Covid-19 Test Results.

Conclusions: The party algorithm was consistent for train and test dataset while for the random forest results were good on train dataset while same model had seen difficulty in prediction class for the test dataset.
Prognosis Of Idiopathic Parkinsonism Using Support Vector Machine And Random Forest Classifiers
Authors: Raghavendra M Devadas, Vani Ashok Hiremani
Published: February 2023

Many of individuals all over the world suffer with Idiopathic Parkinsonism (IP) which is more common in people over 50. Even today, despite numerous technological developments and breakthroughs, early disease identification is still difficult. This calls for the development of machine learning-based automatic methods that assist doctors in accurately identifying this disease in its early stages. This research paper's main goal is to give a thorough analysis of and comparison of the current machine learning methods used for IP detection. In order to compare and determine which of the two classifiers is the most effective and accurate for classifying IP, this paper discusses Support Vector Machine and Random Forest on a dataset. Accuracy and Kappa scores for support vector machine is 85.6% and 0.814. Accuracy 86.45% and kappa score of 0.81 was found in random forest.
Results on Hefty V4-Vertex Magic Graph Labeling
Authors: S. Kavitha, V.L. Stella Arputha Mary
Published: February 2023

Let V4 be an abelian group under multiplication. Let g : E(G) →V4 −{1}. The vertex magic labeling on V4 is defined as the vertex labeling g∗ : V (G) →V4 such that ), where the product is taken over all edges uv of G incident at v is a constant. If the constant is 1, it becomes a Hefty V4-vertex magic labeling. A graph is said to be Hefty V4-magic graph if it admits a Hefty V4-vertex magic labeling. In this paper we investigate the Hefty V4-vertex magic labeling behaviour of graphs like Bipartite, Complete graph, Cayley graph etc.
Diaphragmatic excursion and pulmonary function in children with cerebral palsy – comparative study
Authors: Thomas Tintu , Narayan Amitesh , Alaparthi Gopala Krishna , Karnad Shreekanth D.
Published: February 2023

Introduction

Cerebral palsy (CP) is a common paediatric disorder occurring in about 2 to 2.5 per1000 live births. Studies have reported that children with cerebral palsy have a high incidence of respiratory problems, with limited evidence regarding diaphragmatic impairment. Thus, the study aims to analyse and compare the diaphragmatic excursion and pulmonary function in children with CP compared to the typically developing children.

Methods

The sample size was calculated as 38, divided into groups of typically developed children (19) and spastic CP children (16). An experienced radiologist assessed the diaphragmatic excursion. The respiratory parameters were assessed using a portable Pulmonary Function Test machine.

Results

A positive significance was seen in the pulmonary function test values (p = 0.00) and diaphragmatic excursion (p = 0.00), showing better values among the typically developed children than the CP group.

Conclusions

The study concludes that children with CP have a reduction in diaphragm excursion and poorer pulmonary values than typically developing children, making them prone to respiratory diseases, thus requiring early intervention.
Subjetividad objetiva: Tras los valores asignados a la arquitectura vernácula por Bernard Rudofsky
Authors: Merino Pérez Marcos
Published: February 2023

La metodología de los estudios sobre arquitectura vernácula ha sido siempre puesta en entredicho tanto por su rigor como por los criterios en los que se fundamenta. Trabajos como el del polifacético arquitecto Bernard Rudofsky han sido cuestionados desde diferentes disciplinas, como la antropología arquitectónica, la sociología, la historia de la arquitectura o la propia arquitectura. Sin embargo, gracias a la subjetividad –objetiva– que existe en la metodología aplicada por Rudofsky, somos capaces de comprender la valoración asignada a cada referencia vernácula analizada. El presente trabajo se centra tanto en la justificación de esta metodología, como en el estudio sistemático y la catalogación de cada una de las referencias sobre su trabajo que se han identificado.
Characterization of Traditional Coatings in Earthen Vernacular Architecture in the Limarí Valley: Their Role in the Conservation of Built Heritage in Chile
Authors: Marchante Patrícia , Rivera Vidal Amanda
Published: February 2023

Despite its seismic activity, Chile has a large number of heritage buildings built with earth. Their conservation depends on elements such as roofing and foundations, but also on the quality of renders and finishing materials. This study seeks to identify and characterize the coating systems and materials used on the wall surfaces of earthen heritage structures in the Limarí valley, Chile, seeking to contribute to the dissemination, promotion, and preservation of these traditional renders. The case studies included are historic buildings in various Limarí valley villages. Render and plaster samples of earthen built heritage were taken for analysis from a diversity of wall structures (such as adobe, pandereta, or quincha) and finishing techniques. Despite differences, the conclusions of our fieldwork and sample observations and analysis allow us to identify effective, common coating systems and finishes.
Büyük Doğu Krizi Çerçevesinde (1875-1878) Sırp Gazetelerindeki (Застава, Србски Народ, Српске Новине) Hersek İsyanı İle İlgili Yazıların Değerlendirilmesi
Authors: Čerevicki Tanja
Published: February 2023

Doğu Sorunu, 19. yüzyılda ortaya çıkan uluslararası bir diplomatik sorundur. Büyük Doğu Krizi ise Doğu Sorunu’nun gelişimindeki en dinamik dönemlerden biridir. 1875 yılında Hersek’te çıkan isyan kısa sürede gelişerek Şark Meselesi’nde yeni bir krize başlangıç teşkil etmiştir. Avrupa güçler dengesi çerçevesinde Büyük Güçlerin müdahalesiyle kriz uluslararası bir sorun hâline gelmiştir. Osmanlı Devleti’ni zor durumda bırakan bu isyanı takip eden süreçte yaşanan 1876 Bulgar İsyanı, 1876 Osmanlı-Sırp-Karadağ Savaşı, 1876 İstanbul Konferansı ile Panslavizm tüm ağırlığını hissettirmiş ve 1877-1878 Osmanlı-Rus Savaşı’na sebep olmuştur. Doğu Sorunu, Sırpların entelektüel seçkinleri için kaçınılmaz bir konuydu. Sırp entelektüel seçkinlerinin önde gelen üyeleri, o zamanlar Sırp halkı için en uygun olan çözümleri önermişler, isyan çıktığında Sırpların önemli gazeteleri o zamanların siyasi durumunu açık bir şekilde ortaya koymuşlardır. Hersek’te son zamanlarda meydana gelen olayları haber veren, Hersek ve Bosna’daki isyanlara ve Sırp halkına sempati duyan halk, Osmanlı Devleti’ne karşı savaş talep etmiştir. Seçkin Sırp politikacılar ve halk, Balkan halkı için Büyük Doğu Krizi konusunda savaşı tek çözüm olarak görmüşlerdir. Çalışmamızda üç gazetenin Застава, Србски НароД ve Српске новине, Hersek İsyanı ile ilgili yazıları, analiz edilecektir. 19. yüzyılın hem Sırp Prensliği’nde hem de Avusturya-Macaristan’da yaşayan Sırp önde gelen siyasi düşünürleri, dergi ve gazetelerde yazılar yazıp yayımlayarak Sırp halkı arasında kamuoyu oluşturmakla sorumluydular. Bu gazeteler o zamanlar Drina, Tuna ve Sava’nın iki yakasında yaşayan Sırplar arasında yaygın olarak okundukları ve bize o zamanın Sırp ulusal ilhamının ana duruş noktaları hakkında değerli bilgiler verdikleri için önemlidirler.
Help-Seeking Behaviors and Mental Well-Being of Albanian Immigrants in Malaysia
Authors: Thartori Voltisa , Ismail Nik A. Hisham , Idrus Faizah , Kassim Siti Kholijah
Published: February 2023

The objective of this study is to explore the life experiences of 18 ethnic Albanian immigrants from Albania and Kosovo currently living in Malaysia or who’d previously lived in Malaysia and currently live in Australia. Specifically, the study explores (i) the obstacles and barriers immigrants face in Malaysia and (ii) the role stigmatization has had regarding the immigrants’ help-seeking behaviors. The study uses the phenomenological case study design and in-depth semi-structured interviews for collecting the data. The results show that narrations regarding phenomena such as cultural shock, permanent residence status, stigmatization toward the immigrants, and being labeled with terms such as Mat Salleh[Westerners] have adversely affected the immigrants’ mental well-being. In addition, the Albanian immigrants, especially the females, felt safer confiding their burdens and challenges with family members and close friends. Negative perceptions, stigmatization, and labeling are among the psychological explanations the Albanian immigrants experienced. These inevitable shortfalls affect the immigrants’ mental well-being and correspond similarly to the experiences of many immigrants all over the world.
Scientific and conceptual aspects of the draft Business Code
Authors:   Tashkent State University of Law, Ruzinazarov Shukhrat
Published: February 2023

"This article for the first time analyzes the meaning, necessity, purpose, subject of legal regulation of the Entrepreneurial Code and current legislation in the field of entrepreneurship. It analyzes the importance and necessity of systematization of legislation on entrepreneurship, the formation of legislation on digital entrepreneurship, and the prospects for improving the priority legal regulation of relations in the virtual space. Special attention is paid to the role and place of business legislation in the regulatory framework, as well as to the legal mechanisms for creating an optimal legislative model of intellectual legal regulation in the implementation of the President’s initiative to adopt the Business Code. Due to the complexity of developing a codification document on the legal regulation of business relations, the development of its conceptual legal framework is clearly formulated. The forms and methods of registration of the current legislation on entrepreneurship and organizational and legal solutions for its optimization are described. Most importantly, the codification of business legislation contains scientific statements to express the true legal framework, taking into account not only the current situation, but also the trends of its development in the context of digital reality. The article, based on a deep scientific and practical analysis, provides a general description of the legal system of legal regulation of business activity in our country. It is noteworthy that the article examines the need to pay special attention to the analysis of international legal instruments in this area, taking into account modern trends in the systematization of legislation. Most importantly, the scientific doctrinal approaches to the question of how it should interact with the Civil Code in the development of the Business Code, and the conclusions on the comprehensive solutions of the author’s views are revealed with convincing evidence and evidence. In particular, about the business legislation of foreign countries, including the need to use the experience of creating German state standards for digital business. This scientific article describes for the first time the basics of organizational and legal solutions to systemic problems in the field of entrepreneurship. Another important aspect of scientific analysis is an in-depth analysis of scientific norms and priorities in the development of the Business Code, as well as its essential aspects from the point of view of the doctrine of business law. It also reveals the essence of some international legal acts and ways of solving systemic problems in the field of entrepreneurship. In addition, on the basis of the study of the scientific foundations and priority areas of norm-setting problem-target issues for the development of the draft Entrepreneurial Code, substantiated conclusions and proposals are justified. "
PENERAPAN MODEL PROBLEM BASED LEARNING UNTUK MENINGKATKAN HASIL BELAJAR IPS KELAS VIIIG SMPN 1 PIYUNGAN
Authors: AMANAH AMANAH
Published: February 2023

The aim of the research is to improve student learning outcomes in Maritime Economics and Agriculture through the application of the Problem Based Learning learning model. This research was conducted at Piyungan 1 Public Middle School in the Even semester of the 2021/2022 Academic Year. The subjects of this study were students of class VIIIG, totaling 30 students consisting of 14 girls and 16 boys. This research is a classroom action research (PTK) which consists of 2 cycles, Cycle I, and Cycle II, each cycle consisting of two meetings. The stages of this research include the stages of planning, implementing, observing, and reflecting. Data collection techniques include observation and learning achievement tests. Data analysis used quantitative descriptive data analysis. The results showed an increase in knowledge test results, the average value in the first cycle of 76.67 increased to 84.00 in the second cycle. The number of students who achieved completeness was 22 (73.33%) students in cycle I increased to 27 (90%) students in cycle II, there were still 3 students in cycle II who had not completed. The results of the learning test achievement of class VIIIG students in maritime economics and agriculture material, the minimum class average score is ?77, the classical completeness has exceeded 85%. The results of the knowledge assessment reach the Minimum Completeness Criteria of 90%. The conclusion in this study is that the application of the Problem Based Learning learning model can improve social studies learning outcomes.
ABSTRAKTujuan dari penelitian adalah meningkatkan hasil belajar siswa pada materi Ekonomi Maritim dan Agrikultur melalui penerapan model pembelajaran Problem Based Learning. Penelitian ini dilaksanakan di SMP Negeri 1 Piyungan pada semester Genap Tahun Pelajaran 2021/2022. Adapun subjek dari penelitian ini adalah siswa kelas VIIIG yang berjumlah 30 siswa terdiri 14 perempuan dan 16 laki-laki. Penelitian ini merupakan penelitian tindakan kelas (PTK) yang terdiri dari 2 Siklus, Siklus I, dan Siklus II setiap siklus terdiri dari dua pertemuan. Adapun tahapan penelitian ini meliputi tahap perencanaan, pelaksanaan, pengamatan, dan refleksi. Teknik pengumpulan data meliputi observasi dan tes hasil belajar. Analisis data menggunakan analisis data deskriptif kuantitatif. Hasil penelitian menunjukkan peningkatan hasil tes pengetahuan, nilai rata- rata pada siklus I sebesar 76,67 meningkat menjadi 84,00 pada siklus II. Jumlah siswa yang mencapai ketuntasan 22(73,33%) siswa pada siklus I naik menjadi 27(90%) siswa pada siklus II, masih ada 3 siswa pada siklus II yang belum tuntas. Hasil pencapaian tes belajar siswa kelas VIIIG pada materi ekonomi maritim dan agrikultur nilai rata-rata kelas minimal ?77, ketuntasan klasikal telah melampaui 85%. Hasil penilaian pengetahuan mencapai Kriteria Ketuntasan Minimal sebesar 90%.Kesimpulan dalam penelitian ini penerapan model pembelajaran Problem Based Learning dapat meningkatkan hasil belajar IPS.
PENERAPAN MODEL PROJECT BASED LEANRNING DALAM PERSPEKTIF ONTOLOGI DAN EPISTEMOLOGI FILSAFAT PENDIDIKAN MATEMATIKA
Authors: RANI THITRA PADMA
Published: February 2023

The purpose of this study is to describe the Project Based Learning model in the perspective of the philosophy of mathematics education in ontology and epistemology. This article is reviewed using library research, examining the Project Based Learning model and the philosophy of mathematics education in terms of ontology and epistemology. The results of the study found that the Project Based Learning model begins with providing problems which are then sought for solutions through the given project. This is in accordance with the ontology of the philosophy of science, namely empiricism and logicalism. The Project Based Learning model also guides students to develop collaborative skills, critical thinking skills and problem solving abilities. Epistemologically according to the flow of constructivism that the process of constructing meaning from one experience is then discussed through a combination of experience that has been owned with new experience to produce new knowledge.
ABSTRAKTujuan dari kajian ini untuk mendeskripsikan model Project Based Learning dalam perspektif filsafat pendidikan matematika secara ontology dan epistemlogi. Artikel ini dikaji menggunaka library research, mengkaji model Project Based Learning dan fisafat pendidikan matematika secara ontology dan epistemology. Hasil kajian menemukan bahwa model Project Based Learning diawali dengan memberikan permasalahan yang kemudian dicari penyelesaiaanya melauli proyek yang diberikan. Hal ini sesuai dengan ontology filsafat ilmu yaitu aliran empirisme dan logikalisme. Model Project Based Learning juga membimbing peserta didik untuk mengembangkan keterampilan kolaboratif, kemampuan berfikir kritis dan kemampuan pemecahan masalah. Secara epistemology sesuai aliran kontruksivisme bahwa proses mengkontruksi artinya dari satu pengelaman kemudian didiskusikan melalui perpaduan pengelaman yang telah dimiliki dengan pengalaman baru menghasilkan sebuah pengetahuan baru.
A Comprehensive Reappraisal of Long-term Aerosol Characteristics, Trends, and Variability in Asia
Authors: Jin Shikuan , Ma Yingying , Huang Zhongwei , Huang Jianping , Gong Wei , Liu Boming , Wang Weiyan , Fan Ruonan , Li Hui
Published: February 2023

Abstract. Changes of aerosol loadings and properties are of importance to understand atmospheric environment and climate change. This study investigates the characteristics and the long-term trends of aerosols of different sizes and types in Asia from 2000 to 2020, by considering multi-source aerosol data, novel analysis method and perspective, all this groundwork promote the acquisition of new discoveries that are different from the past. The geometric mean aggregation method is applied, and serial auto-correlation is considered to avoid overestimation of trend significance. Among regions in Asia, high values of aerosol optical depth (AOD) are mainly concentrated in East Asia (EA) and South Asia (SA), closely related to population density. The AOD in EA showed the most significant negative trend with a value of -5.28×10-4 per year, mainly owing to decreases in organic carbon (OC), black carbon (BC), and dust aerosols. It is also worth noting that this observed large-scale decrease in OC and BC is a unique and significant phenomenon to region of EA, and mainly around China. By contrast, the aerosol concentrations in SA generally show a positive trend, with an increase value of AOD of 1.25×10-3 per year. This increase is mainly due to large emission of fine-mode aerosols, such as OC and sulphate aerosol. Additionally, the high aerosol loading in north SA has lower AOD variability comparing with that of East China plain, revealing a relatively more persistent air pollution situation. Over the whole Asia region, the characteristics of percentage changes in different type AOD are increases in BC (6.23 %) and OC (17.09 %) AOD with a decrease in dust (-5.51 %), sulphate (-3.07 %), and sea salt (-9.80 %) AOD. Except for anthropogenic emission, the large increase in the percentage of OC is also owing to wild fires found in Northern Asia in the summer. Whereas, the different size AOD only shows slight changes in Asia, that small-size AOD decreases (-3.34 %), and the total AOD did not show a significant change, suggesting that, from a trend perspective, decreases in aerosol in recent years have mostly been offsetting earlier increases in anthropogenic emission over Asia. To summarize, the above findings analyse the comprehensive characteristics of aerosol distributions and reappraise the long-term trends of different aerosol parameters, which will greatly enhance the understandings of regional and global aerosol environment and climatology, as well as fill in the gaps and break through the limitation of past knowledge.
Non-spherical microparticle shape in Antarctica during the last glacial period affects dust volume-related metrics
Authors: Chesler Aaron , Winski Dominic , Kreutz Karl , Koffman Bess , Osterberg Erich , Ferris David , Thundercloud Zayta , Mohan Joseph , Cole-Dai Jihong , Wells Mark , Handley Michael , Putnam Aaron , Anderson Katherine , Harmon Natalie
Published: February 2023

Abstract. Knowledge of microparticle geometry is essential for accurate calculation of ice core volume-related dust metrics (mass, flux, and particle size distributions) and subsequent paleoclimate interpretations, yet particle shape data remain sparse in Antarctica. Here we present 41 discrete particle shape measurements, volume calculations, and calibrated continuous particle time series spanning 50–16 ka from the South Pole Ice
Core (SPC14) to assess particle shape characteristics and variability. We used FlowCAM, a dynamic particle imaging instrument, to measure aspect
ratios (width divided by length) of microparticles. We then compared those results to Coulter counter measurements on the same set of samples as well as high-resolution laser-based (Abakus) data collected from SPC14 during continuous flow analysis. The 41 discrete samples were collected during three periods of millennial-scale climate variability: Heinrich Stadial 1 (18–16 ka, n=6; ∼250 years per sample), the Last Glacial Maximum (LGM) (27–18 ka, n=19; ∼460 years per sample),
and during both Heinrich Stadial 4 (42–36 ka, n=8; ∼620 years per sample) and Heinrich Stadial 5 (50–46 ka,
n=8; ∼440 years per sample). Using FlowCAM measurements, we calculated different particle size distributions (PSDs) for spherical and ellipsoidal volume estimates. Our calculated volumes were then compared to published Abakus calibration techniques. We found that Abakus-derived PSDs calculated assuming ellipsoidal, rather than spherical, particle shapes provide a more accurate representation of PSDs measured by Coulter counter, reducing Abakus to Coulter counter flux and mass ratios from 1.82 (spherical assumption) to 0.79 and 1.20 (ellipsoidal assumptions; 1 being a perfect match). Coarser particles (>5.0 µm diameter) show greater variation in measured aspect ratios than finer particles (<5.0 µm). While fine particle volumes can be accurately estimated using the spherical assumption, applying the same assumption to coarse particles has a large effect on inferred particle volumes. Temporally, coarse and fine particle aspect ratios do not significantly change within or among the three time periods (p value >0.05), suggesting that long-range transport of dust is likely dominated by clay minerals and other elongated minerals.
CAMx-UNIPAR Simulation of SOA Mass Formed from Multiphase Reactions of Hydrocarbons under the Central Valley Urban Atmospheres of California
Authors: Jo Yujin , Jang Myoseon , Han Sanghee , Madhu Azad , Koo Bonyoung , Jia Yiqin , Yu Zechen , Kim Soontae , Park Jinsoo
Published: February 2023

Abstract. The UNIfied Partitioning-Aerosol phase Reaction (UNIPAR) model was established on the Comprehensive Air quality Model with extensions (CAMx) to process Secondary Organic Aerosol (SOA) formation by capturing multiphase reactions of hydrocarbons (HCs) in regional scales. SOA growth was simulated using a wide range of anthropogenic HCs including ten aromatics and linear alkanes with different carbon-lengths. The atmospheric processes of biogenic HCs (isoprene, terpenes, and sesquiterpene) were simulated for the major oxidation paths (ozone, OH radicals, and nitrate radicals) to predict day and night SOA formation. The UNIPAR model streamlined the multiphase partitioning of the lumping species originating from semi-explicitly predicted gas products and their heterogeneous chemistry to form non-volatile oligomeric species in both organic aerosol and inorganic aqueous phase. The CAMx-UNIPAR model predicted SOA formation at four ground urban sites (San Jose, Sacramento, Fresno, and Bakersfield) in California, United States during wintertime 2018. Overall, the simulated mass concentrations of the total organic matter, consisting of primary OA (POA) and SOA, showed a good agreement with the observations. The simulated SOA mass in the urban areas of California was predominated by alkane and terpene. During the daytime, low-volatile products originating from the autoxidation of long-chain alkanes considerably contributed to the SOA mass. In contrast, a significant amount of nighttime SOA was produced by the reaction of terpene with ozone or nitrate radicals. The spatial distributions of anthropogenic SOA associated with aromatic and alkane HCs were noticeably affected by the southward wind direction owing to the relatively long lifetime of their atmospheric oxidation, whereas those of biogenic SOA were nearly insensitive to wind direction. During wintertime 2018, the impact of inorganic aerosol hygroscopicity on the total SOA budget was not evident because of the small contribution of aromatic and isoprene products that are hydrophilic and reactive in the inorganic aqueous phase. However, an increased isoprene SOA mass was predicted during the wet periods, although its contribution to the total SOA was little.
Assessing riverbank erosion in Bangladesh using time series of Sentinel-1 radar imagery in the Google Earth Engine
Authors: Freihardt Jan , Frey Othmar
Published: February 2023

Abstract. Riverbank erosion occurs along many of the Earth's river systems, affecting riverine populations by destroying agricultural land and housing. In this study, we detected past events of riverbank erosion along the Jamuna River in Bangladesh using time series of Sentinel-1 satellite radar imagery, ground-range-detected (GRD) data with a 12 d revisit cycle, available in
the Google Earth Engine (GEE). Eroded land is detected by performing a land
cover classification and by detecting land cover changes from vegetated
areas before the monsoon to sand or water after the monsoon. Further,
settlements are detected as persistent scatterers and classified as eroded
if they are located on eroded land. We found that with Sentinel-1 data,
erosion locations can be determined already 1 month after the end of the
monsoon and hence potentially earlier than using optical satellite images
which depend on cloud-free daylight conditions. Further, we developed an
interactive GEE-based online tool allowing the user to explore where
riverbank erosion has destroyed land and settlements along the Jamuna in
five monsoon seasons (2015–2019). The source code of our implementation is
publicly available, providing the opportunity to reproduce the results, to
adapt the algorithm and to transfer our results to assess riverbank erosion
in other geographical settings.
Towards long-term records of rain-on-snow events across the Arctic from satellite data
Authors: Bartsch Annett , Bergstedt Helena , Pointner Georg , Muri Xaver , Rautiainen Kimmo , Leppänen Leena , Joly Kyle , Sokolov Aleksandr , Orekhov Pavel , Ehrich Dorothee , Soininen Eeva Mariatta
Published: February 2023

Abstract. Rain-on-snow (ROS) events occur across many regions of the terrestrial Arctic in mid-winter. Snowpack properties are changing, and in extreme cases ice layers form which affect wildlife, vegetation and soils beyond the duration of the event. Specifically, satellite microwave observations have been shown to provide insight into known events. Only Ku-band radar (scatterometer) has been applied so far across the entire Arctic. Data availability at this frequency is limited, however. The utility of other frequencies from passive and active systems needs to be explored to develop a concept for long-term monitoring. The latter are of specific interest as they can be potentially provided at higher spatial resolution. Radar records have been shown to capture the associated snow structure change based on time-series analyses. This approach is also applicable when data gaps exist and has capabilities to evaluate the impact severity of events. Active as well as passive microwave sensors can also detect wet snow at the timing of an ROS event if an acquisition is available. The wet snow retrieval methodology is, however, rather mature compared to the identification of snow structure change since ambiguous scattering behaviour needs consideration. C-band radar is of special interest due to good data availability including a range of nominal spatial resolutions (10 m–12.5 km). Scatterometer and SAR (synthetic aperture radar) data have therefore been investigated. The temperature dependence of C-band backscatter at VV (V – vertical) polarization observable down to −40 ∘C is identified as a major issue for ROS retrieval but can be addressed by a combination with a passive microwave wet snow indicator (demonstrated for Metop ASCAT – Advanced Scatterometer – and SMOS – Soil Moisture and Ocean Salinity). Results were compared to in situ observations (snowpit records, caribou migration data) and Ku-band products. Ice crusts were found in the snowpack after detected events (overall accuracy 82 %). The more crusts (events) there are, the higher the winter season backscatter increase at C-band will be. ROS events captured on the Yamal and Seward peninsulas have had severe impacts on reindeer and caribou, respectively, due to ice crust formation. SAR specifically from Sentinel-1 is promising regarding ice layer identification at better spatial details for all available polarizations. The fusion of multiple types of microwave satellite observations is suggested for the creation of a climate data record, but the consideration of performance differences due to spatial and temporal cover, as well as microwave frequency, is crucial. Retrieval is most robust in the tundra biome, where results are comparable between sensors. Records can be used to identify extremes and to apply the results for impact studies at regional scale.
Biogeochemical evolution of ponded meltwater in a High Arctic subglacial tunnel
Authors: Dubnick Ashley J. , Spietz Rachel L. , Danielson Brad D. , Skidmore Mark L. , Boyd Eric S. , Burgess Dave B. , Dhoonmoon Charvanaa , Sharp Martin
Published: February 2023

Abstract. Subglacial environments comprise ~10 % of Earth’s land surface, host active microbial ecosystems, and are important components of global biogeochemical cycles. However, the broadly inaccessible nature of subglacial systems has left them vastly understudied, and research to date has been limited to laboratory experiments or field measurements using basal ice or subglacial water accessed through boreholes or from the glacier margin. In this study, we extend our understanding of subglacial biogeochemistry and microbiology to include observations of a slushy pond of water that occupied a remnant meltwater channel beneath a polythermal glacier in the Canadian High Arctic over winter. The hydraulics and geochemistry of the system suggest that the pond water originated as late-season, ice-marginal runoff with less than ~15 % solute contribution from subglacial sources. Over the eight months of persistent sub-zero regional temperatures, the pond gradually froze, cryo-concentrating solutes in the residual water by up to seven times. Despite cryo-concentration and the likely influx of some subglacial solute, the pond was depleted in only the most labile and biogeochemically-relevant compounds, including ammonium, phosphate, and dissolved organic matter, including a potentially labile tyrosine-like component. DNA amplicon sequencing revealed decreasing microbial diversity with distance into the meltwater channel. The pond at the terminus of the channel hosted a microbial community inherited from late-season meltwater, which was dominated by only six taxa related to known psychrophilic/psychrotolerant heterotrophs that have high metabolic diversity and broad habitat ranges. Collectively, our findings suggest that generalist microbes from the extraglacial or supraglacial environments can become established in subglacial aquatic systems and deplete reservoirs of nutrients and dissolved organic carbon over a period of months. These findings extend our understanding of the microbial and biogeochemical evolution of subglacial aquatic ecosystems and the extent of their habitability.
Forced and internal components of observed Arctic sea-ice changes
Authors: Dörr Jakob Simon , Bonan David B. , Årthun Marius , Svendsen Lea , Wills Robert C. J.
Published: February 2023

Abstract. The Arctic sea ice cover is strongly influenced by internal variability on decadal time scales, affecting both short-term trends and the timing of the first ice-free summer. Several mechanisms of variability have been proposed, but how these mechanisms manifest both spatially and temporally remains unclear. The relative contribution of internal variability to observed Arctic sea ice changes also remains poorly quantified. Here, we use a novel technique called low-frequency component analysis to identify the dominant patterns of winter and summer decadal Arctic sea-ice variability in the satellite record. The identified patterns account for most of the observed regional sea ice variability and trends, and thus help to disentangle the role of forced and internal sea ice changes over the satellite record. In particular, we identify a mode of decadal ocean-atmosphere-sea ice variability, characterized by an anomalous atmospheric circulation over the central Arctic, that accounts for approximately 30 % of the accelerated decline in pan-Arctic summer sea-ice area between 2000 and 2012. For winter sea ice, we find that internal variability has dominated decadal trends in the Bering Sea, but has contributed less to trends in the Barents and Kara Seas. These results, which detail the first purely observation-based estimate of the contribution of internal variability to Arctic sea ice trends, suggest a lower estimate of the contribution from internal variability than most model-based assessments.
Isotopic diffusion in ice enhanced by vein-water flow
Authors: Ng Felix S. L.
Published: February 2023

Abstract. Diffusive smoothing of signals on the water stable isotopes (18O and D) in ice sheets fundamentally limits the climatic information retrievable from these ice-core proxies. Past theories explained how, in polycrystalline ice below the firn, fast diffusion in the network of intergranular water veins “short-circuits” the slow diffusion within crystal grains to cause “excess diffusion”, enhancing the rate of signal smoothing above that implied by self-diffusion in ice monocrystals. But the controls of excess diffusion are far from fully understood. Here, modelling shows that water flow in the veins amplifies excess diffusion, by altering the three-dimensional field of isotope concentration and isotope transfer between veins and grains. The rate of signal smoothing depends not only on temperature, vein and grain sizes, and signal wavelength, but also on vein-water flow velocity, which can increase the rate by 1 to 2 orders of magnitude. This modulation can significantly impact signal smoothing at ice-core sites in Greenland and Antarctica, as shown by simulations for the GRIP and EPICA Dome C sites, which reveal sensitive modulation of their diffusion-length profiles when vein-flow velocities reach ~ 101–102 m yr–1. Velocities of this magnitude also produce the levels of excess diffusion inferred by previous studies for the Holocene ice at GRIP and ice of Marine Isotope Stage 19 at EPICA Dome C. Thus, vein-flow mediated excess diffusion may help explain the mismatch between modelled and spectrally-derived diffusion lengths in other ice cores. We also show that excess diffusion biases the spectral estimation of diffusion lengths from isotopic signals (by making them dependent on signal wavelength) and the reconstruction of surface temperature from diffusion-length profiles (by increasing the ice contribution to diffusion length below the firn). Our findings caution against using the monocrystal isotopic diffusivity to represent the bulk-ice diffusivity. The need to predict the pattern of excess diffusion in ice cores calls for systematic study of isotope records for its occurrence and improved understanding of vein-scale hydrology in ice sheets.