bluuebunny/crossref_metadata_2025 huggingface dataset:
La regulación de las zonas de seguridad en la zona económica exclusiva y la plataforma continental. Breve referencia a Cuba
Authors: Torres Tesoro Miguel E.
Published: June 2022

Según el derecho internacional, el Estado ribereño podrá establecer, alrededor de islas artificiales, instalaciones y estructuras, zonas de seguridad en la Zona Económica Exclusiva (ZEE) y la Plataforma Continental. En dichas Zonas se podrán tomar medidas apropiadas para garantizar la seguridad de la navegación y de las islas artificiales, instalaciones y estructuras. Dichas zonas tienen una extensión consensuada de hasta 500 metros alrededor de las infraestructuras mencionadas, aunque la propia Convención de las Naciones Unidas sobre el Derecho del Mar permite que la organización internacional pertinente pueda ampliarlo, en este caso la Organización Marítima Internacional (OMI). La CONVEMAR obliga a declarar la Zona, pero no regula la prohibición de entrada y otras situaciones que pudieran ocurrir dentro de dicha Zona, ni la competencia para detener y reprimir a los infractores de los reglamentos establecidos para las Zonas de Seguridad (en casos que lo Estados ribereños decidan establecerlos). A través de estudios comparados y los instrumentos internacionales en vigor, pretendemos encontrar aquellas regulaciones que le permiten al Estado extender parte de su jurisdicción a las Zonas de Seguridad en ZEE y Plataforma Continental. Eso sí, limitado a la naturaleza de las operaciones de las islas artificiales, instalaciones y estructuras.
ILMU FALAK (Dimensi Kajian Filsafat Ilmu)
Authors: Mujab Sayful , Nasir M. Rifa Jamaludin
Published: June 2022

Artikel ini membahas bagaimana Ilmu Falak diulas dalam filsafat ilmu. Data penelitian digali dari berbagai literatur ilmiah dan selanjutnya dianalisis secara kualitatif. Hasil penelitian menunjukkan bahwa Ontologi, Epistemologi, dan Aksiologi Ilmu Falak menjadi kajian penting bagi eksistensi Ilmu Falak sebagai ilmu yang mapan dalam dunia ilmu.

 

This article discusses how Ilmu Falak is reviewed in the philosophy of science. The research data were extracted from various scientific literature and then analyzed qualitatively. The results showed that the Ontology, Epistemology, and Axiology of Ilmu Falak became an important study for the existence of Ilmu Falak as a science that is well established in the world of science.
Green-Synthesis Of Silver Nanoparticles Based On Bioreductor Key Orange Extract As Antibacterial
Authors: Afriani Fitri , Susanti Susanti , Ramadhani Fadillah , Soraya Muntaz , Evi.J Evi.J
Published: June 2022

Silver nanoparticles are nano-sized particles ranging from 1-100 nm which are commonly used as antifungal and antibacterial agents in various products. In this study, silver nanoparticles were synthesized from a natural bioreductant, namely key orange peel extract. The silver nanoparticle phase which was successfully synthesized and then XRD test was carried out was cubic in shape with the highest peak at 2θ : 38.1959˚; 44.4038˚; 64.5491˚ The lattice parameter of silver nanoparticles is a=b=c= 4.0861 . The resulting crystal structure of silver nanoparticles is cubic with a crystallite size of 39.84 nm, in addition to XRD test, XRF test was conducted to determine the main constituent components of silver nanoparticles, while the main component of synthesized silver nanoparticles was Ag of 97.66%. Antibacterial activity of silver nanoparticles was indicated by the formation of inhibition against the growth of Staphylococcus aureus bacteria with a clear zone formed around 12.091 mm. Therefore, the antibacterial inhibition formed from the silver nanoparticles synthesized in this study can be classified as a strong antibacterial property.
Literature Review of Learning Media Development using 3D Pageflip in Physics Learning
Authors: Putra Andri Yanto , Mufit Fatni
Published: June 2022

Technological progress in the 21st century is progressing very rapidly, one of the fields that has an impact on the development of technology and knowledge is in the field of education. Where the development of technology is increasingly developing interactive multimedia-based media that can assist teachers in delivering material to students and students also more easily understand the material being taught. One of the media development software that has an effective, easy and attractive appearance to use is 3d pageflip. This research is a descriptive study with data analysis techniques using percentages which are then analyzed by descriptive techniques. This research refers to 10 articles that are relevant to the research, namely media development with 3d pageflip. The results of this study are obtained that the average articles developed already have valid criteria, the types of teaching materials that are mostly developed with 3d pageflip are EBooks and the materials developed are different from 10 articles there are 9 different materials developed.
Testing of Macroeconomic Factors Affecting Capital Markets with Granger Causality Method: Turkey Practice
Authors: Kantar Lokman
Published: June 2022

Purpose-In this study, the relationship between the capital market (BIST 100 index) and macroeconomic variables that are thought to affect thecapital market (gold prices, oil prices, Euro-US Dollar exchange rate basket, budget balance, foreign trade balance) will be examined with the Granger causality method.Design/methodology/approach-The study covers the period of 2010-2019 on a monthly system. The data were obtained from the CBRT (EDDS) and TurkStat. Statistical package software (Stata and EViews 9) were used in the analysis of the data. BIST 100 index return is included in the model as a dependent variable and macroeconomic factors as an independent variable. The relationship between dependent and independent variables was examined with the VAR-based Granger causality method.Findings-As a result of the study, it has been understood that only the gold price among the macroeconomic factors is the Granger cause of the BIST 100 index. In other words, lagged changes in gold prices explain the variance of the BIST 100 index. When the direction of the relationship was examined, a one-way Granger causality was observed from the Ons variable to theBIST 100 variable. When the action-reaction shocks between the BIST 100 variable and the ONS variable are examined, a shock in gold prices affected the return of the BIST 100 index for about 2 months, and this effect decreased and disappeared from the 5thmonth. Again, approximately 6.82% of the variance of the BIST100 variable is explained by the Ons variable.Discussion-Developments in the capital markets are followed closely by both institutional investors and individual investors. For this reason, it is extremely important what factors affect the BIST 100 index, which is thought to represent the Turkish capital market. According to the findings of the study, changes in gold prices affect the BIST 100 index return, and the relationship between these twovariables should be closely monitored. Addressing the long-term relationship between the BIST 100 index and gold prices in future studies will make an important contribution to the literature
Research the Impact of COVID-19 on the Tourism Service Industry – Macau SAR
Authors: Lio Chong In
Published: June 2022

COVID-19 broke out in the earth in 2020, economic and social development of the Macao SAR has brought huge economic losses and inestimable impact on the tourism service industry. This research focuses on the tourism service industry in the Macao SAR, study the economic trend and impact of the COVID-19 on the tourism service industry. Analyze the impact of the enterprise from the four aspects of the enterprise's production and operation, the use of funds, the sales method and the company's management, research put forward the difficulties and problems encountered by the tourism service industry enterprises. The study provides feasible recommendations and measures for the tourism service industry to address the impact of the COVID-19 and restore economic development.
The Impact of Afghanistan's Changed Situation on India's Geo-environment
Authors: Zhang Chunfang
Published: June 2022

Afghanistan's changed situation was one of the biggest international changes in 2021, causing violent shocks to the world. As an important neighboring country of Afghanistan, India has significant economic and security interests in Afghanistan. The change in Afghanistan has not only directly affected the bilateral relations between India and Afghanistan, but also has triggered a new round of regional power games involving India, Pakistan, Russia, Iraq and other countries. At the same time, the change in Afghanistan is also related to the adjustment of United States’ global strategy. As a result, the situation in Afghanistan has had a profound and extensive impact on India's geo-environment.
Cultural Tracing and Political Power: Historical Narrative of the Chengdu Traditional Chinese Medicine College in the 1950s
Authors: Chen Keji
Published: June 2022

Chengdu Traditional Chinese Medicine College is one of the first four TCM colleges in the People’s Republic of China founded in 1956. The central government made the establishment decision and Chengdu face the southwest of China to enroll. The College’s training objectives, educational system, and student number were all uniformly stipulated by the top. The College planned to train senior practitioners with Marxist and Leninist ideas and mastery of Chinese medicine academic knowledge and medical technology for Socialist Construction and people’s healthcare. The founding of the Chengdu College of TCM is on the track of modern Chinese medical history. Chinese medicine has become an issue to debate since modern times, in the face of the abolition crisis and scientific discussions, Chinese medicine education is learning from the West to promote. The close connection between traditional medicine and the mass reflects its cultural connotation. The rehabilitation of Chinese medicine as a medical discipline is inseparable from the ruling party’s support. Chinese medicine is a tool to consolidate the regime of the Chinese Communist Party. Founding the TCM colleges is beneficial for training many practitioners to serve the state power.
The Research Dynamics and Trends of Aesthetics, Based on Scientific Knowledge Mapping: An Analysis of the Papers Published in the British Journal of Aesthetics (2001-2022) and the Journal of Aesthetics and Art Criticism (2011-2022)
Authors: Jia Li , Chen Xiurong , Huang Li
Published: June 2022

This paper is based on the papers published in recent 10 years (2001-2022) from The British Journal of Aesthetics and The Journal of Aesthetics and Art Criticism, both of which enjoy high reputation in the aesthetic field. This paper uses scientific knowledge mapping and draws the knowledge mapping by using CiteSpace. Guided by visualization of conclusions, it outlines some development trends of aesthetics discipline and presents the research hot spots and changes of international aesthetics from a new perspective. Then this paper discusses the characteristics of aesthetics itself.
Polyphonic Theory in the Perspective of Intersexuality—The Relationship Between Bakhtin’s Polyphonic Novel and Polyphonic Music
Authors: Xu Nuo
Published: June 2022

The “polyphonic novel”, as defined by Mikhail Bakhtin, has a limited connection, commonality and a great difference with the “polyphonic music” in the history of Western music. The “interartistry (a concept derived from intersexuality, meaning intersexuality between two categories of art)” between the two can be examined in two ways: the intertextuality of the two theories themselves, and the profound artistic dialogue between Bakhtin and the composer Mikhail Glinka on an intellectual level that is not separated from the “intersubjectivity”. The heterogeneity between the two is mainly manifested in the dichotomous characteristics of “opposition and imitation” and “contradiction and harmony”. The “interartistry” of polyphonic novel and polyphonic music is examined from the perspective of “intersextuality”, which helps to fully understand the connection and difference between them and reduce the interdisciplinary misuse and abuse of related terms.
Corporate social responsibility disclosure before and during the Covid-19 pandemic
Authors: Cahyaningsih Cahyaningsih , Septyaweni Asty
Published: June 2022

The COVID-19 pandemic has had a significant impact on the condition of the Indonesian economy, including the manufacturing industry. Therefore, it is necessary to test the effect of tax aggressiveness, environmental performance, and media exposure on corporate social responsibility disclosure. Corporate social responsibility disclosure is measured using the criteria set out in the 2017 Financial Services Authority (OJK) regulation. This study used 77 observational data from the 2017–2020 period in which the descriptive statistical analysis showed a decrease in tax aggressiveness, environmental performance, media exposure, and corporate social responsibility disclosure. The results showed significant differences in the manufacturing companies' corporate social responsibility disclosures before and during the COVID-19 pandemic. The findings revealed that tax aggressiveness and environmental performance positively affected corporate social responsibility disclosure. In contrast, media exposure did not affect corporate social responsibility disclosure. However, media exposure positively affected environmental aspects disclosure. These results indicated that manufacturing companies have social and environmental awareness.
Director experience, management compensation and tax avoidance
Authors: Asih Sri , Setiawan Doddy
Published: June 2022

The purpose of this study is to analyze the effect of director experience and management compensation on tax avoidance in Indonesia. This is quantitative research with secondary data sources using cross section data. Purposive sampling was used to obtain 267 observation samples of manufacturing companies listed on the Indonesia Stock Exchange from 2018 to 2020 tested using multiple linear regression analysis. Dependent variable of tax avoidance proxied by cash effective tax rate is used. The director’s experience and management compensation are independent variables in this study. The director’s experience is measured by using the dummy variable of the director’s experience during study or work abroad. Management compensation is proxied by using the natural logarithm of the annual compensation received by management. Some control variables are also used such as firm size, leverage, firm age, return on assets, growth, market to book ratio, and debt to equity ratio. We found that there is a significant negative relationship between director's experience and management's compensation on tax avoidance. In conclusion, director's experience and management compensation are both important for tax avoidance decisions in companies.
Aplikasi Suhu terhadap Mortalitas Hama Sitophilus zeamais dan Tribolium castaneum pada Jagung
Authors: Susanti Rini
Published: June 2022

Warehouse pests are nuisance pests that cause a decrease in the quality and quantity of harvested grains. Sitophilus zeamais and Tribolium castaneum are important warehouse pest of corn. Apart from attacking corn grains, this pests also attacks rice, wheat, sorghum, soybeans, grain/rice, and green beans. Temperature is a very influential aspect in the life of all insect species, including warehouse pests. This study aimed to determine the appropriate temperature range for controlling warehouse pests of Sitophilus zeamais and Tribolium castaneum which does not interfere with health and is also safe for consumers. This research was conducted at the Pest Laboratory, Faculty of Agriculture, UMSU. The method used was factorial completely randomized design (CRD), the first factor was the use of temperature and the second factor was duration of heating with three replications. The results showed that the application of a temperature of 100 0C for 120 seconds or 150 0C for 60 seconds could cause the mortality of S. zeamais and T. castaneum pests to reach 100% in corn grains in storage.
APPLICATION OF OZONE TECHNOLOGY AS AN EFFORT TO INCREASE THE ECONOMIC VALUE OF VEGETABLE COMMODITIES
Authors: Prabawa Sigit , Amanto Bambang Sigit , Kawiji Kawiji , Yudhistira Bara
Published: June 2022

Vegetables are classified as food ingredients that are easily wilted and easily damaged so that vegetables that have been harvested must be marketed and consumed immediately. At room temperature, the freshness of leaf vegetables can only last for 12 hours. For this reason, proper postharvest handling is needed to maintain quality and extend the shelf life of these commodities, including ozone technology (ozonization). Ozone is able to shed pesticide and bacterial contamination as well as heavy metals attached to the surface of fruit or vegetables, making it safe for consumption for health. Vegetable cultivation by productive communities as micro-entrepreneurs has developed quite a lot. The problem that still occurs is the lack of efforts to extend the shelf life of vegetables that can increase consumer preferences for spinach. The “Mutiara Organik” Farmer Group in Sumberejo Village, Ngablak District, Magelang Regency made these efforts by cultivating vegetables and applying ozonation. The program begins with the introduction of packaging technology and continues with the presentation of permits from the Ministry of Health for ozonized organic vegetables. This program provides farmers with a set of production tools and packaging. The analysis also shows that ozone treatment provides higher efficiency, because it can reduce weight loss compared to Japanese spinach without ozone treatment. In addition, ozone treatment has the potential to increase vegetable productivity and quality.

Keywords: ozonization; shelf life; vegetables
Penerapan Regresi Least Absolute Shrinkage And Selection Operator (LASSO) Untuk Mengidentifikasi Variabel Yang Berpengaruh Terhadap Kejadian Stunting di Indonesia
Authors: Pardede Tesa Trilonika
Published: June 2022

Linear regression analysis is an analytical method that can be used to analyze data and draw meaningful conclusions about the dependence of one variable on another variable. In linear regression analysis there are several assumptions that must be met, namely normal distribution, there is no correlation between errors. There are several obstacles that cause the assumption to be unfulfilled, for example the occurrence of correlations between independent variables (multicollinearity). The analysis in this study uses the Least Absolute Shrinkage And Selection Operator (LASSO) regression method with the Least Angle Regression (LAR) algorithm because the stunting data in Indonesia has multicollinearity problems among the independent variables used. LASSO which can solve the case of multicollinearity in the regression at the same time it is possible to reduce the regression coefficient from the highly correlated independent variable to exactly zero. The LASSO coefficient obtained uses quadratic so that the LAR algorithm is used which is more efficient in LASSO computing. Based on the analysis that has been carried out, it is concluded that the variables of exclusive breastfeeding (X1), protein consumption (X2), DPT-HB exercise (X5), maternal height (X8) and diarrhea (X9) had an effect on stunting in Indonesia in 2018.
Prediksi Pergerakan Saham Menggunakan Metode Simulasi Monte Carlo untuk Pembentukan Portofolio Optimal dengan Pendekatan Model Markowitz
Authors: Megawati  , Resmawan  , Payu Boby Rantow , Adityaningrum Amanda
Published: June 2022

Stock movements that follow a stochastic process move randomly at certain times, have led stock prices challenging to predict. For this reason, the monte carlo simulation method is used to get the possibilities of stock prices in the future. This case study focused on the shares listed on the Jakarta Islamic Index 70 in 2018, by simulating 10 times the daily closing price data, thus, the possible stock prices in 2019 were obtained. Portfolio optimization was then carried out using the markowitz model approach from the predicted data. Based on the prediction data, there are 20 stock have a positive expected return. The stocks that has the largest weight is ICBP.JK (Indofood CBP Sukses Makmur Tbk) stocks, with 0.1396, while the stocks with the smallest weight is INAF.JK (Indofarma (Persero) Tbk) at 0.0053. Histirical simulations calculate the Value a Risk of 20 stocks that provide optimal returns, if investors invest Rp. 100,000,000.00 the maximum risk or loss that will be obtained is Rp. 2,910,410.00 for 1 year.
Analisis Data Kecepatan Angin di Pulau Jawa Menggunakan Distribusi Weibull
Authors: Atika Ratna Dewi  , Sri Handini
Published: June 2022

Wind is one of the renewable energy products that is environmentally friendly and has a great opportunity as a source of meeting the energy needs of the world's population. In the use of wind as renewable energy, research must be carried out first to determine wind conditions in an area and the method that can be used is the Weibull distribution. In this journal, what will be discussed is the analysis of wind speed data on the island of Java using the Weibull distribution. From the results of the analysis, the wind speed results by province are as follows, Banten Province 2 m/s with a probability of 65%, DKI Jakarta 3 m/s with a probability of 30%, West Java 3 m/s with a probability of 90%, Central Java 8 m/s s with a probability of 11%, East Java 7 m/s with a probability of 7%, DI Yogyakarta is less than 1 m/s with a probability of 98%. The results of the plot of the probability solid function of the Weibull distribution show that the shape of the provincial velocity data curve that corresponds to the Weibull distribution curve is only the curve of East Java Province with a value of 1 < k < 2, namely k = 1.74.
On the trade-off between compression efficiency and distortion of a new compression algorithm for multichannel EEG signals based on singular value decomposition
Authors: Campobello Giuseppe , Gugliandolo Giovanni , Quercia Angelica , Tatti Elisa , Ghilardi Maria Felice , Crupi Giovanni , Quartarone Angelo , Donato Nicola
Published: June 2022

In this article we investigate the trade-off between the compression ratio and distortion of a recently published compression technique specifically devised for multichannel electroencephalograph (EEG) signals. In our previous paper, we proved that, when singular value decomposition (SVD) is already performed for denoising or removing unwanted artifacts, it is possible to exploit the same SVD for compression purpose by achieving a compression ratio in the order of 10 and a percentage root mean square distortion in the order of 0.01 %. In this article, we successfully demonstrate how, with a negligible increase in the computational cost of the algorithm, it is possible to further improve the compression ratio by about 10 % by maintaining the same distortion level or, alternatively, to improve the compression ratio by about 50 % by still maintaining the distortion level below the 0.1 %.
A cost-efficient reversible logic gates implementation based on measurable quantum-dot cellular automata
Authors: Latha Gade Mary Swarna , Rooban Sudanthiraveeran
Published: June 2022

In order to improve the density on a chip, the scaling of CMOS-based devices begins to shrink in accordance with Moore's laws. This scale affects the execution of the CMOS device due to specific limitations, such as energy dissipation and component alignment. Quantum-dot cellular automata (QCA) have been replaced to overcome the inadequacies of CMOS technology. Data loss is a major risk in irreversible digital logic computing. As a result, the market for nano-scale digital operations is expanding, reducing heat dissipation. Reversible logic structures are a strong competitor in the creation of efficient digital systems. A reversing logic gate is an important part of reversible circuit design. The QCA design of basic reversible logic gates is discussed in this study. These gates are built using a new QCA design with XOR gates with two and three inputs. QCADesigner tests simulation performance by simulating the specified reversible logic gate layouts. The measurement and optimization of design techniques at all stages is required to reduce power, area, and enhance speed. The work describes experimental and analytic approaches for measuring design metrics of reversible logic gates using QCA, such as ancilla input, garbage output, quantum cost, cell count, and area, while accounting for the effects of energy dissipation and circuit complexity. The parameters of reversible gates with modified structures are measured and then compared with the existing designs. The designed F2G, FRG, FG, RUG and UPPG reversible logic gates using QCA technology shows an improvement of 42 %, 23 %, 50 %, 39 % and 68 % in terms of cell count and 31 %, 20 %, 33 %, 20 % and 72 % in terms of area with respect to the best existing designs. The findings illustrate that the proposed architectures outperform previous designs in terms of complexity, size, and clock latency.
Scaffolding Process Based on Error Analysis in Solving the Problem: Second Order Differential Equation
Authors: Noor Naili Luma'ati
Published: June 2022

Error analysis in solving mathematics problems is needed to be done so that the lecturer and the students can find out the students’ error in solving the problems. So, in the future the lecturer will administer the more appropriate scaffolding. The aim of this research is to analyze the appropriate scaffolding administered for the students based on error identification according to the Newman procedure of the students in solving second order differential equation. The method of this research was qualitative research case study design. The subject of the research was the students of mathematics education study program at IAIN Kudus who took differential equation class in the first semester in the academic year 2021/2022. The technique for data collection used were test and interview techniques. The result of the research of scaffolding administered for the students was by the techniques of inviting student participation, the students who performed comprehension errors obtained scaffolding in the form of offering explanations and verifying and clarifying student understandings, the students who performed transformation errors obtained offering explanations and modeling of desired behaviors techniques, the students who performed process skill errors obtained scaffolding in the form of Inviting students to contribute clues and Inviting student techniques, and the students who performed encoding errors obtained scaffolding in the form of Inviting student participation.

 

Analisis kesalahan dalam menyelesaikan masalah matematika perlu dilakukan agar dosen dan mahasiswa dapat mengetahui kesalahan mahasiswa dalam menyelesaikan masalah. Jadi, kedepannya dosen akan mengelola scaffolding yang lebih tepat. Penelitian ini bertujuan untuk menganalisis scaffolding yang tepat diberikan kepada siswa berdasarkan identifikasi kesalahan menurut prosedur Newman siswa dalam menyelesaikan persamaan diferensial orde dua. Metode penelitian ini adalah penelitian kualitatif dengan desain studi kasus. Subyek penelitian ini adalah mahasiswa program studi pendidikan matematika di IAIN Kudus yang mengambil mata kuliah persamaan diferensial pada semester I tahun ajaran 2021/2022. Teknik pengumpulan data yang digunakan adalah teknik tes dan wawancara. Hasil penelitian scaffolding yang diberikan kepada siswa adalah dengan teknik mengundang partisipasi siswa, siswa yang melakukan kesalahan pemahaman memperoleh scaffolding berupa menawarkan penjelasan dan memverifikasi dan memperjelas pemahaman siswa, siswa yang melakukan kesalahan transformasi memperoleh penjelasan menawarkan dan teknik pemodelan perilaku yang diinginkan, siswa yang melakukan kesalahan keterampilan proses memperoleh scaffolding berupa mengundang siswa untuk menyumbangkan petunjuk dan teknik Mengundang siswa, dan siswa yang melakukan kesalahan encoding memperoleh scaffolding berupa mengundang partisipasi siswa.
Using Intelligent Tutoring Systems Through Cognitive Tutor Authoring Tools to Solve Filling Slot Problems
Authors: Hermawan Faried
Published: June 2022

Intelligent Tutoring Systems (ITS) is a computer system that provides instructions and is adapted to students who apply learning by doing theory. Cognitive Tutor Authoring Tools (CTAT) is one of ITS that supports the creation of flexible tutors for simple problems and complex solutions, able to support several strategies so that they can describe what students do when solving problems. In working on the problem of filling the place, students will solve the problem according to the students' logic of thinking. This is because the logic of thinking of each student is different depending on the information he receives. For this reason, in this study, the use of CTAT will be tried in working on filling slot questions using media, namely Intelligent Tutoring Systems (ITS) which uses Cognitive Tutor Authoring Tools (CTAT) tools. In this study, students have obtained the filling slot material first. Only then is the media used which will later be used to work on filling slot questions with different problems. From this research, it was found that the results of the study were increasing students' understanding in working on filling slot questions using Cognitive Tutor Authoring Tools (CTAT) media.So that the Cognitive Tutor Authoring Tools (CTAT) media can be used as an alternative learning media to develop students' understanding of filling slot material.

Intelligent Tutoring Systems (ITS) adalah sistem komputer yang memberikan instruksi dan disesuaikan dengan siswa yang menerapkan learning by doing theory. Cognitive Tutor Authoring Tools (CTAT) merupakan salah satu ITS yang mendukung terciptanya tutor yang fleksibel untuk masalah sederhana dan solusi kompleks, mampu mendukung beberapa strategi sehingga dapat menggambarkan apa yang dilakukan siswa saat menyelesaikan masalah. Dalam mengerjakan soal aturan pengisian tempat, siswa akan menyelesaikan soal tersebut sesuai dengan logika berpikir siswa. Hal ini dikarenakan logika berpikir setiap siswa berbeda-beda tergantung dari informasi yang diterimanya. Untuk itu pada penelitian ini akan dicoba penggunaan CTAT dalam mengerjakan soal aturan pengisian tempat menggunakan media yaitu Intelligent Tutoring Systems (ITS) yang menggunakan tools Cognitive Tutor Authoring Tools (CTAT). Pada penelitian ini siswa telah memperoleh materi aturan pengisian tempat terlebih dahulu. Baru kemudian digunakan media yang nantinya akan digunakan untuk mengerjakan soal aturan pengisian tempat dengan soal yang berbeda. Dari penelitian ini diketahui bahwa hasil penelitian adalah peningkatan pemahaman siswa dalam mengerjakan soal aturan pengisian tempat menggunakan media Cognitive Tutor Authoring Tools (CTAT). Sehingga media Cognitive Tutor Authoring Tools (CTAT) dapat digunakan sebagai media pembelajaran alternatif untuk mengembangkan pemahaman siswa terhadap materi aturan pengisian tempat.
Think You Know Where Proppant Goes During Fracturing? Based on Recent Testing: Don’t Bet on It
Authors: Rassenfoss Stephen
Published: June 2022

Completion engineers have figured out some rules of thumb about how proppant flows based on decades of experience.

That knowledge was put to the test when GEODynamics created a fracturing surface test that offered a full-size, full-pressure recreation of a stage design created by its initial backer, PDC Energy.

Before the oilfield service company’s first test was pumped. those involved put their money into a pool with the winner based on who most accurately predicted how much sand flowed out of each cluster.

“The one that won the bet was the CFO who had no idea how fracs were supposed to work. The worst were the ones that thought they knew fracturing,” said Phil Snider, a consultant on the project who played a key role in the design of the test.

Like the pool, the test results diverged from the widespread assumption that the fluid and the sand flow out in roughly equal proportions at each cluster.

The results suggested “proppant and fluid does not move as uniformly as many believe,” said Steve Baumgartner, senior engineering technical advisor at GEODynamics, while describing the testing at the recent SPE Hydraulic Fracturing Technology Conference and Exhibition (HFTC).

Some of the results were consistent with earlier studies using computer modeling and less-realistic flow tests showing that many fast-flowing sand grains slip past the first few clusters in a stage.

GEODynamics found that medium-sized proppant (40–70 mesh) is likely to slip past early stages, resulting in reduced outflow in early clusters and more flowing out later in the stage. But if the grains are smaller (100 mesh), the distribution is more even.

A second round of tests showed that a change in the fracture design aimed at achieving more even slurry distribution from cluster to cluster further reduced the differences among clusters, but bigger grains still tended to slip past early clusters.

What GEODynamics made public is a first look at an ingenious bit of engineering used for a series of tests that ended in 2019, before COVID-19 hit (SPE 209141).

The idea for the test goes back to questions raised by past fracturing jobs. For example, when a well where data gathered during fracturing indicated all clusters were effectively stimulated, but later analysis indicated about half of them failed to produce. Why?

“This nonuniformity can be attributed in part to formation variability and stress shadowing from adjacent fracture stages, but nonuniform flow of proppant in the casing can also play an important role,” said a second paper on creating a model for completion engineering.

The notion that sand grains and fluid do not move in lockstep does not seem surprising because sand grains are likely to behave differently from a mix of water and friction reducer.

The hard question for any engineer who wants to begin designing completions based on the assumption that fluid and sand flows are not similar is how to quantify that difference.
The World Casts New Eyes on Nuclear
Authors: Wright Blake
Published: June 2022

Images conjured by the mere mention of the term “nuclear energy” are almost always negative. From Chernobyl to Fukushima, the power source has a historically bad reputation and the stigma of catastrophe. Winston Churchill knew those that failed to learn from history were doomed to repeat it, and perhaps it is lessons learned that have so many countries once again casting a keen eye over conventional nuclear energy as a potential key player in the low-carbon future.

For the first time in more than a decade, most Japanese are in support of restarting idled nuclear facilities, according to a poll conducted by Nikkei. Rising power prices and the potential for electricity shortages in Tokyo are said to have swayed many back to being in favor of nuclear power just 10 years after the Fukushima disaster. The poll found 53% of respondents in favor of restarting the reactors if safety could be assured, while 38% said they should remain shut.

With Russia continuing its invasion into neighboring Ukraine, many European countries are looking to rid themselves of dependence on Russian natural gas imports. Many have grown so dependent they cannot fully shut the stream off for fear of economic collapse, however several are attempting to rework their own energy policies and favoring nuclear as a solution. Both France and the UK have reversed course on nuclear in recent months. Just ahead of Russia’s invasion of Ukraine, French President Emmanuel Macron called for a nuclear renaissance in his country after earlier vowing to cut its reliance on nuclear power. The UK, which gets 15% of its electricity from nuclear power, had vowed to shutter all but one of its plants ahead of the Russian invasion. More recently, Prime Minister Boris Johnson is favoring the construction of new plants and boosting Britain’s electrical generation from nuclear to 25%.

As for the US, at the end of 2021 there were 55 commercially operating nuclear power plants with 93 nuclear power reactors in 28 states. The newest nuclear plant to enter service in the US was Watts Bar Unit 2, which began commercial operations in 2016. Two new nuclear reactors are actively under construction: Georgia Power’s Vogtle Units 3 and 4 in Waynesboro, Georgia.

A recent Pew survey found that while a majority of Americans (69%) favor the US taking steps to become carbon neutral by 2050, only around a third of US adults (35%) say the federal government should encourage the production of nuclear power, while about a quarter (26%) say the government should discourage it (Fig. 1). This survey was fielded before the Russian invasion and the renewed discussions about nuclear power it has prompted.

According to the US Energy Department’s Office of Nuclear Energy, nuclear power currently provides 52% of the US’s carbon-free electricity, and the Biden administration has identified the current fleet of 93 reactors as a vital resource to achieve net-zero emissions economywide by 2050.
Modeling, Planning Allow Successful Implementation of South Texas U-Turn Lateral
Authors: Carpenter Chris
Published: June 2022

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 208801, “Successful Planning and Implementation of First South Texas U-Turn Lateral,” by Riley Schultz and Joe Kiefner, Chesapeake Energy. The paper has not been peer reviewed.

Legacy fields require innovative solutions for developing capitally efficient projects within highly developed acreage blocks. As another tool to improve well economics, a U-turn lateral strategy was implemented in the Eagle Ford Shale. This wellbore trajectory resulted in capturing a 9,200-ft equivalent lateral length well in a 5,000-ft-wide lease space. This successful U-turn trajectory test has created new economic project opportunities for the company and has increased optionality within challenged lease spaces across the field.

Well Overview

In a single U-turn well, the horizontal wellbore turns 180° to create two parallel laterals in a map-view U shape. The successful U-turn project detailed in the complete paper was the first drilled in south Texas (Fig. 1). This resulted in significantly improved economics by using a horizontal turn as a hydrocarbon pathway, rather than an additional vertical section from a new well to gain the equivalent treatable lateral length.

This well followed operator standards for south Texas Eagle Ford two-casing-string well design. A 9⅝-in. casing was set to protect shallow water zones, and an 8¾-in. production section was drilled for the remainder of the well (using 5½-in. drillpipe). 5½-in. production casing was then run to total depth (TD). 8¼-in. centralizers were placed on each joint of the casing, freely floating between the collars. The production section was drilled with oil-based mud, and a standard cement job was pumped. Conventional directional tools were used for the entirety of the drilling phase.

The decision was made early in the planning phase of the well to forgo fracturing the turn portion of the wellbore and instead drill into the adjacent unit to conduct the turn to maximize the amount of optimally oriented lateral footage in the unit to be produced.
Examining the groundwater level in a semi-arid district of eastern India: spatiotemporal trends, determinants, and future prospects
Authors: Goswami Tarun , Ghosal Somnath
Published: June 2022

The present study aims to examine the spatio-temporal and seasonal fluctuation of groundwater levels in an eastern Indian semi-arid region. Also, it attempted to investigate the involvement of different significant groundwater usage factors in causing such variations and trends. Furthermore, by evaluating temporal patterns and the influence of the crucial drivers, generate meaningful predictions for raising community awareness about the future. A combination of statistical, spatial analysis, and machine learning techniques were used to fulfill the objectives. Overall, the findings revealed that the south-eastern corner (consisting of Bundwan and Barabazar Blocks), the far western region (especially Jhalda I and II Blocks), and some of the eastern Blocks are most vulnerable to groundwater scarcity. The monitoring stations in this region are typically suffering a significant declining trend in groundwater level, with a substantial amount of Sen's Slope. In contrast, the centrally positioned Blocks have lesser susceptibility. The MLR analysis and spatial thematic maps demonstrate a strong association between this spatial pattern of declining groundwater table and the groundwater drivers in consideration. Thus, it is acceptable to suggest that drivers from the human world must be included in the groundwater management planning of the Purulia district. Finally, the predictions from the time series confirm that if no interventions are implemented, the average groundwater level will decline by 2.5 meters by 2030. Therefore, Purulia urgently requires a realistic plan to prevent future generations from becoming refugees in their own land.
Tunable properties of the absorption in a binary photonic crystal having a metamaterial as a defect layer and two graphene sheets in the range of GHz
Authors: Almawgani Abdulkarem H. M. , Sharma Arvind , Daher Malek G. , Taya Sofyan A. , Colak Ilhami , Patel Shobhit K.
Published: June 2022

Light absorption is essential in the construction of photodetectors and photovoltaic applications. In this work, the absorption properties of a defective photonic crystal are analyzed in the GHz region using the transfer matrix method. The defect layer is assumed to be a metamaterial of negative optical parameters sandwiched between two sheets of graphene. The tunable properties of absorption are investigated with the graphene chemical potential and phenomenological scattering rate and the thickness of the metamaterial layer. The results reveal that the number, position and height of the absorption resonant peaks are tuned by graphene optical properties. The spectra are studied with and without graphene sheets and an extra peak is created when two sheets of graphene are inserted on both sides of the metamaterial. The proposed photonic device can be useful in designing graphene and metamaterial-based optical devices such as absorbers, filters and sensors in the GHz region.
The Risk Assessment of Relapse among Newly-enrolled Participants in Methadone Maintenance Treatment: A Group-Lasso Based Bayesian Networks Study
Authors: Tang Xijia , Fan Chaonan , Wang Chijie , Wang Wenjuan , Chen Zouxiang , Xu Chaofan , Ling Li
Published: June 2022

Relapse is a great barrier to improving the effectiveness of methadone maintenance treatment (MMT). Participants with different treatment durations could vary in the compliance with MMT, which may lead to different levels of relapse risk. This study aims to identify the risk factors for relapse and assess the relapse risk of MMT participants of different treatment durations. This retrospective study used data collected from 9 MMT clinics in Guangdong Province, China from January 2010 to April 2017. Newly enrolled participants who received 6 (n = 903) and 12 (n = 710) months of consecutive treatment with complete data were include. We selected significant risk factors for relapse through group-lasso regression and then incorporated them into Bayesian networks to reveal relationships between factors and predict the relapse risk. The results showed that participants who received 6-month treatment had a lower relapse rate (32.0%) than those of 12-month (39.0%, P<0.05). Factors including personally living status and daily methadone dose were only influential to those who received 6-month treatment rather than those after 12-month treatment. However, age, age at the initial drug use, HIV infection status, sexual behaviors, and continuous treatment days were common factors of both durations. The highest relapse risk for those after 6-month treatment was inferred as 66.7% while that of 12-month treatment was 83.3%. Farmers and those who have high accessibility to MMT services may require additional attention. Therefore, it is of necessity to implement targeted interventions and education based on the treatment durations of participants to decrease the relapse rate. Meanwhile, those about HIV/sexually transmitted infection prevention and anti-narcotics should be held in the entire process.
COVID-19 vaccination trends and side effects among Egyptian hemodialysis patients: a multicenter survey study
Authors: Nassar Mohammed Kamal , Salem Karem Mohamed , Abdel-Gawad Sara M , Tharwat Samar
Published: June 2022

Background: Patients on chronic hemodialysis (CHD) for end stage kidney disease (ESKD) face unique circumstances that increase their risk of infection with coronavirus disease (COVID-19). Vaccination may be a key intervention to prevent infection in these patients. This study aimed to determine the COVID-19 vaccination status in Egyptian CHD patients and analyze the safety and detailed side effect profile of COVID-19 vaccine among these patients. Methods:This survey-based study conducted on 670 ESRD patients on CHD at the period from 3 December 2021 to 5 February 2022. Subjects were asked about sociodemographic characteristics, clinical and therapeutic data, history of COVID-19 infection, associated symptoms and sequalae in addition to their COVID-19 vaccination status. If the subject had been vaccinated, we inquired about the type of vaccine and the side effects that occurred within few days after administrating of the first and second dose of COVID-19 vaccine. Additionally, subjects were inquired about the onset of side effects (days from vaccination), timing of maximum symptoms, intensity of symptoms and their effect on activity and need for medical attention.Results:The study included 670 CHD patients with mean age of 50.79 years ,58.1% were females. Of them, one hundred and seventy-three patients (25.8%) had previously been infected with COVID-19. About three fourths (72.2%) reported that healthcare providers (HCP) strongly endorsed COVID-19 vaccine. The vast majority (614; 91.6%) of the studied patients received 2 doses of the vaccine. AstraZeneca and Sinopharm were the most used vaccines (50.3% and 35.5% respectively). Side effects were commonly reported after the first dose than the second dose. The main general side effects that reported after the first dose were generalized weakness/fatigue (56%), headache (43.8%) and fever (40.4%). Sore arm/pain was reported in about one third (29.3%) after the first dose. Myalgia and generalized muscle pain was reported in 90 (14.7%) patients after the first dose and 9 (1.5%) after both doses. Anxiety (25.4%), psychological stress (12.9%), increase in sleep (9.3%), depression (2.8%) and decrease in memory (2%) were reported among recipients after the first dose and rarely reported after the second one. Adverse events mostly occurred within one day after vaccination and the maximum symptoms usually happened at the second day. The median duration of symptoms was 3 days with maximum duration up to 5 days. Only 4.2% required transient time off from work.Conclusions:Our preliminary findings support the favorable short term safety profile of COVID-19 vaccine among CHD patients and hence, can reassure both clinicians and patients, as well as promote further COVID-19 vaccine administration among these patients.