bluuebunny/crossref_metadata_2025 huggingface dataset:
Parameter Influence on Porous Bleed Performance for Supersonic Turbulent Flows
Authors: Giehler Julian , Grenson Pierre , Bur Reynald
Published: September 2023

Porous bleed systems are a common technique to control shock-/boundary-layer interactions and/or supersonic boundary layers. However, the influence of various design parameters is still unknown. Even though porous bleed models are required to minimize the costs of the design process, they often do not include parameter effects. In the present study, the effect of the plate length, the hole diameter, the porosity level, the thickness-to-diameter ratio, and the stagger angle are investigated by means of three-dimensional Reynolds-averaged Navier–Stokes simulations. The bleed efficiency and the effectiveness in thinning a Mach [Formula: see text] turbulent boundary layer are determined. The findings show a crucial influence of the hole diameter on both the efficiency and effectiveness of the porous bleed. Similar findings are made for the porosity and stagger angle but with a smaller significance. The thickness-to-diameter ratio and plate length are shown to mainly affect the bleed efficiency.
Data-Driven Diagnosis of Multicopter Thrust Fault Using Supervised Learning with Inertial Sensors
Authors: Kim Taegyun , Kim Seungkeun , Shin Hyo-Sang
Published: September 2023

This study proposes a data-driven fault diagnosis for multicopter unmanned aerial vehicles that uses the principal direction vector of inertial measurement unit (IMU) sensor signals calculated by principal component analysis. The main idea comes from the fact that a normal sphere-shaped distribution of the sensor data changes to a specific elliptical shape under a certain thrust fault situation. The fault diagnosis is based on classification and regression using supervised learning with the gyroscope and accelerometer datasets of an IMU. We analyze the performance of the proposed approach by depending on different learning algorithms. To verify the diagnostic performance, ground experiments with a hexacopter on the gimbaled jig are performed for various cases of damaged propellers. Then, the applicability of the proposed data-driven fault diagnosis is confirmed by analyzing the accuracy of the fault’s location and degree.
Wall-Resolved Large-Eddy Simulation of Flow over a Parametric Set of Gaussian Bumps
Authors: Rizzetta Donald P. , Garmann Daniel J.
Published: September 2023

Wall-resolved large-eddy simulations were carried out for the flow over a parametric set of Gaussian bumps, which are representative of surfaces generating smooth-body separation. The geometry and flow conditions were motivated by an experimental investigation, which was conducted in order to provide data for validating numerical approaches. Because the high-Reynolds-number and three-dimensional shape of the experimental model is challenging, even for approximate numerical techniques, a prior investigation was initiated in order to provide benchmark results that are accessible via wall-resolved large-eddy simulation. It was found that by increasing the bump height, the Reynolds number could be reduced, and flow separation would occur. The modified bump now serves as a surrogate for the original Gaussian bump, producing smooth-body separation. In the present study, solutions are obtained to the unsteady three-dimensional compressible Navier–Stokes equations utilizing a high-fidelity computational scheme and an implicit time-marching approach. A series of simulations is carried out for bumps of varying heights, for both the three-dimensional configuration and a spanwise-periodic subset, corresponding to flow at the midspan. A number of metrics are provided to attest to the accuracy of simulations. Comparisons are made between the spanwise-periodic subset and the three-dimensional configuration, and features of the flowfields are described. The generation of an arch vortex structure evolving about the speed bump geometry is elucidated.
The Role of Friction in the LISA-Pathfinder Release Mechanism Anomaly
Authors: Vignotto Davide , Zanoni Carlo , Tomasi Matteo , Bortoluzzi Daniele , Ricca Edoardo Dalla , Pretto Isacco , Radaelli Paolo
Published: September 2023

Release mechanisms are crucial devices for the success of space missions. In LISA, the first gravitational waves observatory in space, the grabbing positioning and release mechanism (GPRM) is responsible for setting all the test masses (TMs) in the free-fall condition necessary for starting science observations. This mechanism is considered a key equipment for the success of the entire space mission. The GPRM was initially tested in LISA Pathfinder (LPF), a space mission flown between 2015 and 2017, and an anomaly was encountered in the TM velocity after the release, which also resulted in some failures. One of the suspected reasons of this behavior is that the trajectory of the release mechanism deviates from the nominally rectilinear one. We find that this anomaly is due to the presence of high and asymmetric friction between moving parts. In this paper, we characterize experimentally the deviation from the linear trajectory, using LPF qualification models of the mechanism available on ground, and we identify the mechanical features that determine the friction-driven spurious lateral motion via a numerical finite element model. The results are one of the basis to improve the design of the GPRM for LISA. Some risk-reduction strategies and design guidelines are also presented and discussed.
PENGARUH PENERAPAN SISTEM INFORMASI MANAJEMEN DAN DECISION SUPPORT SYSTEM TERHADAP EFEKTIVITAS KERJA KARYAWAN PADA PT BANK bjb CABANG CIAMIS
Authors: Sari Desi Ratna Juwita , Nursolih Enjang , Suhendi Roni Marsiana
Published: September 2023

Penelitian ini difokuskan pada Sistem Informasi Manajemen (SIM) dan Decision Support System (DSS), terhadap efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis. Permasalahan yang dihadapi dalam penelitian ini meliputi (1) Apakah Sistem Informasi Manajemen (SIM) berpengaruh terhadap efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis, (2) Apakah Decision Support System(DSS) berpengaruh terhadap efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis, (3) Apakah SIM dan DSS secara simultan (bersama-sama) berpengaruh terhadap  efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis. Tujuan penelitian ini adalah (1) Untuk mengetahui apakah Sistem Informasi Manajemen (SIM) ber         ,  pengaruh terhadap efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis, (2) Untuk mengetahui apakah Decision Support System(DSS) berpengaruh  terhadap efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis bjb Cabang Ciamis, (3) Untuk mengetahui apakah SIM dan DSS secara simultan (bersama-sama) berpengaruh terhadap efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis. Metode yang digunakan pada penelitian ini adalah metode survey dengan pendekatan kuantitatif, dimana sampel penelitian sebanyak 57 karyawan PT Bank bjb Cabang Ciamis. Untuk menganalisis data yang diperoleh digunakan analisis deskriptif meliputi analisis koefesien korelasi sederhana, analisis koefisien korelasi berganda, analisis regresi berganda, analisis koefesien determinasi, dan Uji Hipotesis menggunakan Uji Signifikansi (Uji t dan Uji F). Hasil penelitian dan pengolahan data menunjukkan bahwa koefisien determinasi (R Square) yang diperoleh sebesar 0,766 hal ini menunjukkan bahwa 76,6% efektivitas kerja karyawan pada PT Bank bjb Cabang Ciamis dipengaruhi oleh variabel Sistem Informasi Manajemen dan variabel Decision Support System. Sedangkan sisanya 23,4% dipengaruhi oleh variabel lain di luar penelitian ini. DiharapkanBagi PT Bank bjb Cabang Ciamis agar kiranya lebih memaksimalkan penerapan Sistem Informasi Manajemen dan Decision Support System di perusahaan khususnya dalam hal ketersediaan informasi, kecukupan informasi, ketepatan waktu penyampaian informasi dan akurasi.
ANALISIS PERENCANAAN DAN PENJADWALAN PROYEK PEMBANGUNAN RUMAH SEDERHANA MENGGUNAKAN NETWORK PLANNING DI DESA SUKAHURIP KECAMATAN CISAGA KABUPATEN CIAMIS
Authors: Hartati Gini , Suryadi Dedi , Maskur Atep
Published: September 2023

Perencanaan dalam waktu proyek adalah salah satu cara untuk mengendalikan  pelaksanaan pekerjaan  yang merupakan  bagian esensi dari setiap aktifitas proyek. Kegagalan proyek akan semakin besar tanpa manajemen waktu yang optimal. Pada setiap pelaksanaan proyek perlu adanya penanganan manajemen penjadwalan proyek yang baik. Suatu proyek dikatakan baik jika penyelesaian proyek tersebut efisien ditinjau dari segi waktu, maka diperlukan cara agar penyelesaian struktur rumah dapat dikerjakan dengan cepat untuk memenuhi kebutuhan masyarakat. 

Tujuan dilakukan penelitiaan ini adalah untuk  membuktikan dan menganalisis apakah network planning dapat digunakan pada proyek pembangunan rumah rumah sederhana. Dan untuk mengetahui metode jaringan kerja  sebagai alat pengendali dan pengawasan dalam pelaksanaan proyek pembangunan rumah rumah sederhana di Desa Sukahurip Kecamatan Cisaga Kabupaten Ciamis

Dari hasil perhitungan perencana dengan Network Planing PERT dan CPM di Kabupaten Ciamis , di temukan adanya perbedaan waktu dan biaya sebelum dan sesudah menggunakan metode Network Planing yang awalnya proyek membutuhkan waktu 133 hari dengan total biaya Rp. 345.300.000,- menjadi 113,01 hari dengan Total biaya Rp. 323.300.000.
ANALISIS KELAYAKAN PENGEMBANGAN USAHA PETERNAKAN SAPI PERAH (Studi Kasus di Peternakan Sapi Panjalu)
Authors: Santang Ilham Eka , Roban Roban , Pratiwi Wieke Dinar
Published: September 2023

Usaha yang akan didirikan merupakan usaha budidaya sapi perah dengan jenis fries Holstein yang berada Kawasan jalan lingkar, Blok Ciborengah Hajatan Ciomas, Situ Lengkong Panjalu Ciamis. Usaha ini dilakukan untuk memberikan kontribusi kepada usaha yang telah didirikan memiliki perkembangan yang lebih baik serta memberikan kenaikan pada pendapatan di sector daerah tersebut, kemudian memberikan lapangan pekerjaan pada warga sekitar. Hal tersebut dilakukan melalui beberapa aspek yaitu melalui analisis aspek pasar dapat diketahui bahwa usaha peternakan sapi perah  yang akan didirikan ini memiliki segmen pasar yang cukup sesuai dengan jumlah populasi sapi perah yang ada, adanya sistem integrasi antara pertanian dan peternakan. Selanjutnya melalui aspek teknis dan produksi adanya lokasi yang strategis dalam mendirikan usaha peternakan serta luas lahan yang cukup serta penerapan bioteknologi menggunakan Inseminasi Buatan (IB). Kemudian melalui aspek SDM (Sumber Daya Manusia), tenaga kerja yang digunakan merupakan pekerja yang diambil dari warga sekitar. Aspek Legalitas dan Lingkungan pun menunjang pendirian usaha peternakan ini yaitu perizinan dari peternakan sapi perah telah di tetapkan sesuai dengan kebijakan pemerintah daerah, selain legalitas dari pendiria perusahaan selanjutnya adalah aspek lingkungan baik itu lingkungan fisik ataupun lingkungan social ekonomi. Usaha yang akan didirikan layak dengan IRR yang didapatkan adalah 308,52 % . Nilai yang di peroleh lebih besar dari MARR sebesar 7,25%, maka dari itu IRR dari kedua kondisi ini diterima, dengan tingkat pengembalian kembali 1 tahun+4bulan .
Optimization of Ulva sp. Decomposition using H2SO4 with Microwave-Assisted Hydrolysis Method as Feedstock of Bioethanol
Authors: Palupi Bekti , Rizalluddin Muhammad , Septianti Kiki , Rahmawati Istiqomah , Fachri Boy Arief , Rizkiana Meta Fitri , Amini Helda Wika
Published: September 2023

Bioethanol is a renewable energy used to reduce dependence on fossil fuels, which have negative impacts on the environment. Furthermore, Ulva sp. contains high levels of carbohydrates, making it potentially suitable as a raw material for bioethanol production. Therefore, this study aims to determine the optimal decomposition process using the microwave-assisted hydrolysis method with an acid solvent (H2SO4), by examining the effects of acid concentration, hydrolysis time, and microwave power. Optimization was carried out using several parameters such as hydrolysis time, microwave power, and the ratio of raw materials to solvents. The ANOVA test results showed that the hydrolysis variable parameter had a significant effect on the reducing sugar content obtained, evidenced by the R2 value of 0.9892. The highest reducing sugar content of 19.71 mg/mL was produced under the operating conditions of 15 min hydrolysis time, 450 W microwave power, and 0.065 g/mL ratio of raw material to solvents.
The Effect of H-Factor on Kappa Number and Viscosity in Continuous Digester
Authors: Putri Rizka Wulandari , Rahmatullah Rahmatullah , Siagian Faisal
Published: September 2023

One of the most important steps in pulping is the cooking process, which serves to separate the cellulose and hemicellulose from lignin and other by-products. During the cooking process in the digester, various factors must be considered to create high-quality pulp. Among these factors, the H-Factor plays a significant role due to its impact on the kappa number and viscosity in the pulping process. A high H-Factor can also damage the strength of the pulp. Therefore, this research aims to investigate the effect of the H-Factor and active alkali on pulp yield and quality. The active alkali used was in line with the desired production objectives, as insufficient levels of active alkali can lead to a low yield of pulp. Meanwhile, pulp quality standards in the Pulp and Paper Industry included kappa number of 12-18 in the digester process, an approximate viscosity of 23 mPa.s, and the selection of H-Factor based on the desired production target.
Analisis Kemampuan Representasi Matematis Mahasiswa Melalui Perkuliahan Geometri Analitik Topik Garis
Authors: Dihna Elza Rahma , Sudihartinih Eyus
Published: September 2023

Penelitian ini bertujuan untuk mendeskripsikan kemampuan representasi matematis mahasiswa dalam menyelesaikan soal geometri analitik. Jenis penelitian yang digunakan dalam penelitian ini adalah penelitian deskriptif dengan menggunakan pendekatan kualitatif. Partisipan pada penelitian ini adalah 12 orang mahasiswa program studi pendidikan matematika yang mengontrak mata kuliah geometri analitik. Instrumen soal yang digunakan pada penelitian ini adalah tiga butir soal uraian pada topik garis. Pada hasil penelitian ini didapatkan bahwa kemampuan representasi matematis mahasiswa calon guru pada mata kuliah geometri analitik dalam topik garis masih kurang. Dari ketiga indikator kemampuan representasi matematis, didapatkan bahwa partisipan dapat dengan baik menampilkan reprsentasi visual berupa gambar atau grafik, kemudian untuk representasi persamaan atau ekspresi matematis dapat dicapai dengan baik oleh hampir seluruh partisipan. Dan indikator yang paling sedikit dicapai oleh partisipan adalah indikator representasi verbal pada indikator ini hanya ada dua partisipan yang mampu menampilkannya.
Meningkatkan Keaktifan Belajar Peserta Didik dengan Model Pembelajaran Kooperatif Tipe Teams Games Tournament (TGT)
Authors: Parhusip Gristi Damaiyanti , Kristanto Yosep Dwi , Partini Partini
Published: September 2023

Penelitian ini bertujuan untuk mendeskripsikan peningkatan keaktifan belajar peserta didik kelas XI MIPA 2 SMAN 1 Ngaglik tahun ajaran 2022/2023 dengan pembelajaran teams, games, and tournament (TGT). Penelitian ini merupakan Penelitian Tindakan Kelas yang dilaksanakan dalam dua siklus. Subjek penelitian ini adalah peserta didik berjumlah 34 peserta didik. Instrumen yang digunakan dalam penelitian ini meliputi lembar observasi keaktifan belajar, lembar angket keaktifan belajar, dan lembar observasi keterlaksanaan pembelajaran. Analisis data yang digunakan adalah analisis data deskriptif kuantitatif dengan menggunakan persentase. Berdasarkan hasil penelitian, disimpulkan bahwa pembelajaran kooperatif tipe TGT dapat meningkatkan keaktifan belajar peserta didik kelas XI MIPA 2 SMAN 1 Ngaglik tahun ajaran 2022/2023 pada materi program linear. Berdasarkan observasi, keaktifan belajar peserta didik mengalami peningkatan rerata sebesar 21,4%, yaitu naik dari 59,2% pada siklus I menjadi 80,6% pada siklus II. Berdasarkan analisis data angket, peningkatan keaktifan belajar juga ditemukan, yaitu sebesar 4,4%, dari rerata 77% pada siklus I menjadi 81,4% pada siklus II.
Implementasi STEM (Science, Technology, Engineering, and Mathematics) terhadap Kemampuan Pemecahan Masalah Matematis dan Penalaran Matematis
Authors: Putri Cyndana Kartika , Juandi Dadang
Published: September 2023

Penelitian ini bertujuan untuk menganalisis pengaruh pendekatan STEM (Science, Technology, Engineering, and Mathematics) terhadap kemampuan pemecahan masalah matematis dan kemampuan penalaran matematis. Metode yang digunakan pada penelitian ini adalah Systematic Literature Review (SLR). Terdapat 6 artikel yang dikaji setelah melalui tahap inklusi dan uji kualitas. Beberapa kriteria inklusi yang ditetapkan yaitu artikel dipublikasi pada rentang tahun 2015-2022, penelitian dilakukan di Indonesia dan menggunakan metode penelitian kuantitatif serta populasi penelitian dapat berasal dari jenjang pendidikan sekolah dasar hingga pendidikan tinggi. Untuk meningkatkan kemampuan pemecahan masalah matematis, model PBL, PjBL maupun karakteristik budaya lokal dapat diintegrasikan dengan pendekatan STEM. Adapun untuk meningkatkan kemampuan penalaran matematis, guru dapat mengimplementasikan model ICARE dengan pendekatan STEM. Hasil kajian literatur yang telah dilakukan menunjukkan bahwa implementasi STEM efektif atau berperan dalam meningkatkan kemampuan pemecahan masalah matematis dan kemampuan penalaran matematis
Kemampuan Koneksi Matematis Siswa SMP pada Materi Statistika
Authors: Imani Risti Atika , Maimunah Maimunah , Roza Yenita
Published: September 2023

Kemampuan koneksi matematis sangat perlu dikuasai siswa, namun kemampuan siswa masih tergolong rendah. Penelitian ini memiliki tujuan yakni untuk mendeskripsikan kemampuan koneksi matematis siswa kelas VIII dalam memecahkan soal materi statistika. Jenis penelitian ini adalah kualitatif deskriptif. Penelitian dilaksanakan di SMPN 5 Bantan kepada 22 siswa. Subjek penelitian dipilih dengan purposive sampling yaitu tiga siswa dimana dipilih satu siswa pada setiap kategori dan indikator kemampuan koneksi matematika. Adapun instrumen yaitu berupa tes kemampuan koneksi matematis pada materi statistika. Data yang diambil berupa hasil tes tertulis siswa dan hasil wawancara siswa yang menjadi subjek penelitian. Hasil penelitian yang diperoleh  adalah: 1) terdapat sebelas siswa yang mendapatkan kategori tinggi, tujuh siswa termasuk dalam kategori sedang, dan empat siswa berkategori rendah; 2) siswa yang memiliki kemampuan rendah kesulitan dalam menyelesaikan soal  karena siswa belum mampu menghubungkan antar konsep matematika, siswa juga belum mampu mengkorelasikan matematika dengan ilmu lain, dan siswa juga belum bisa mengaplikasikan matematika pada kehidupan sehari-hari.
Analisis Kesalahan Siswa dalam Menyelesaikan Soal Cerita Sistem Persamaan Linier Tiga Variabel (SPLTV) Berdasarkan Prosedur Newman
Authors: Hidayanto Erry , Lisrahmat Mimin Nazura
Published: September 2023

The purpose of this study was to describe the form of student errors in solving SPLTV story questions based on Newman's procedures and their causes. This research method uses a qualitative approach with a descriptive qualitative research type with the subject of three students of class X a high school in Malang. The forms of errors found in this study were: unable to read the questions carefully, unable to understand the meaning of each important symbol or term contained in the questions; unable to understand the important information contained in the questions, incorrectly in writing the information implied in the questions, not writing down any information either known or asked from the questions; less precise in making illustrations for each variable used, not writing illustrations used for each variable in the equations that have been made, unable to transform the information in the problem into mathematical form correctly and precisely; unable to continue the calculation procedure until the final answer is found, incorrectly in writing the calculation results obtained from the elimination process; did not write the final answer, did not include the units in the final answer, incorrectly wrote the units in the final answer, did not write the conclusion of the final answer according to what was asked or asked for in the question. The causes of these errors: not being careful, in a hurry, not focusing, afraid of running out of time, being careless, and not checking the final answer.
Differences in Mathematics Concept Understanding Ability And Learning Independence of Students Reached with Discovery Learning and Cooperative Learning Model Type of Group Investigation at SMK Multi Karya
Authors: Purba Putri Anggraini , Sitompul Pardomuan , Napitupulu E Elvis
Published: September 2023

: To find out the characteristics and advantages supported by data from previous research, which shows that learning with discovery and cooperative learning models of group investigation type can improve students' ability to understand mathematical concepts and independent learning. The findings obtained several conclusions related to implementing learning using the discovery learning model and the group investigation learning model on differences in the ability to understand mathematical concepts and student learning independence at SMK Multi Karya.

 
Pengaruh STEM-PjBL terhadap Keterampilan Berpikir Kreatif Siswa MTS
Authors: Firmantara Muhammad Reza , ‎ ‎Sudarti Sudarti , Handayani Rif'ati Dina
Published: September 2023

Penelitian ini bertujuan untuk mengetahui model PjBL berbasis STEM (STEM-PjBL) terhadap keterampilan berpikir kreatif siswa. Populasi penelitian ini adalah siswa kelas VIII pada kelas kontrol dan eksperimen MTS Nurul Islam Lumajang. Sampel penelitian satu kelas dengan menggunakan teknik purposive sampling. Penelitian ini merupakan penelitian eksperimental yang instrumennya menggunakan tes keterampilan berpikir kreatif. Data hasil penelitian dianalisis secara statistik. Hasil penelitian bermakna bahwa model STEM-PjBL dapat meningkatkan keterampilan berpikir kreatif yang ditunjukkan oleh tes N-Gain pada kelas kontrol dan eksperimen. Kesuksesan pembelajaran STEM-PjBL pada penelitian ini diharapkan mampu berperan dalam meninmgkatkan mutu siswa di pembelajaran abad 21. Hasilnya pada aspek kelancaran (fluency), fleksibilitas (flexibility), keaslian (originality), elaborasi (elaboration) dengan hasil cukup efektif: 61%, 60%,  61%, 61%. walaupun semua aspek mengalami peningkatan berdasarkan pretest dan postest
Analisis Kualitas Soal Ujian Akhir Semester Dengan Menggunakan Aplikasi Program Anates
Authors: Wedastuti Ni Ketut , Fuady Anies , Sunismi Sunismi
Published: September 2023

Penelitian ini bertujuan untuk (1) menentukan item kualitas soal ujian dalam hal reliabilitas, tingkat kesukaran, dan daya pembeda, (2) menerapkan software anates untuk menghitung  reliabilitas, tingkat kesulitan dan daya pembeda. Metode penelitian yang digunakan adalah teknik deskriptif kuantitatif dan teknik dokumentasi. Datanya terdiri dari 31 lembar jawaban siswa pada kelas VIIA SMPN 6 Singosari Malang tahun ajaran 2022/2023 . Data-data tersebut dianalisis, reliabilitas, tingkat kesulitan, pembedaan daya menggunakan software anates. Hasil penelitian menunjukkan bahwa Reliabilitas soal tergolong baik berdasarkan software anates yang menunjukkan nilai koefisien 𝑟11>𝑟𝑡𝑎𝑏𝑒𝑙. Tingkat kesukaran butir soal kurang baik karena keseimbangan soal yang mudah sedang dan sukar belum proposional, keseimbangan yang proposional yaitu 3 5-2 atau 3-4- 3.Terdapat 3 butir soal (15%) baik sekali, 4 butir soal (20%) tergolong baik, 6 butir soal (30%) tergolong sedang, 6 butir soal (30%) tergolong kurang baik dan 1 butir soal (5%) tergolong jelek sekali berdasarkan analisis daya beda.
Implementasi Pembelajaran Matematika Berbasis Wirausaha Dalam Menumbuhkan Disposisi Matematis Siswa Sekolah Menengah Kejuruan
Authors: Meslita Rima
Published: September 2023

The research aims to find ways to implement entrepreneurial-based mathematics learning in cultivating the mathematical dispositions of  students at SMKN 1 Tanjung Jabung Barat. This research was analyzed by means of descriptive qualitative. Research subjects employed purposive sampling as many as 10 people. The resultseshowed that in the implementation of learning mathematics in cultivating students' mathematical dispositions, 7 research subjects were included inethe very goodecategory and 3 research subjects were included in the fairly good category. The obstacles encountered in the process of growing the mathematical disposition of students at the School include students not understandingeabout learning simulationsewith the concept of buyingeand selling or better known as Market day. Students think that if an activity involves them spending money or capital, even though the activity is a bridgeefor students to understandethe material. Students with their own understanding without a teacher and learning about these activities makes students unmotivated, which reduces students' creativity and self-confidence
Trend Publication of Computational Thinking in Mathematics Education: Bibliometric Review
Authors: Maharani Swasti , Susanti Vera Dewi , Andari Tri , Krisdiana Ika , Astuti Indra Puji
Published: September 2023

Computational thinking and mathematics are closely related, namely mathematics plays a role in overcoming challenges and understanding concepts in computational thinking, while computational thinking ultimately simplifies and abstracts situations by formulating and presenting problems in mathematical form. The purpose of this study is to identify trends and research patterns with the topic of computational thinking in mathematics education using bibliometric analysis. Data is obtained from the dimensions database which has been refined through 4 stages (identification, screening, eligibility, and inclusion). The results showed that the peak of publications related to computational thinking in mathematics education research occurred in 2022. The Journal of Science of Education and Technology became the most influential journal with the most citations, namely 877 citations even though it only with 7 publications. The United States is the most influential country in this field because of the good number of publications, the number of citations is the highest of any other country. There are three research focuses related to computational thinking in mathematics education research on the dimensions database from 2013-2023, namely, 1) mathematics, study, teacher; 2) problem, child, learning; 3) student, steam, CT skill
Efficient Electron Hopping Transport through Azurin-Based Junctions
Authors: Roldán-Piñero Carlos , Romero-Muñiz Carlos , Díez-Pérez Ismael , Vilhena José Guilherme , Pérez Rubén , Cuevas Juan Carlos , Zotti Linda Angela
Published: September 2023

We conducted a theoretical study into electron transport through junctions of the blue-copper azurin from Pseudomonas aeruginosa. We found that single-site hopping can lead to either higher or lower current values compared to fully-coherent transport. This depends on the structural details of the junctions as well as the alignment of the protein orbitals. Moreover, we show how the asymmetry of the IV curves can be affected by the position of the tip in the junction and that, under specific conditions, such a hopping mechanism is consistent with a fairly-low temperature dependence of the current. Finally, we show that increasing the number of hopping sites leads to higher hopping currents. Our findings, from fully-quantum calculations, provide deep insight to help guide the interpretation of experimental IV curves on highly-complex systems.
Exploring the Chemical Subspace of RPLC: a Data Driven Approach
Authors: van Herwerden Denice , Nikolopoulos Alexandros , Barron Leon , O'Brien Jake , Pirok Bob , Thomas Kevin , Samanipour Saer
Published: September 2023

The chemical space is comprised of a vast number of possible structures, of which an unknown portion comprises the human and environmental exposome. Such samples are frequently analyzed using non-targeted analysis via liquid chromatography (LC) coupled to high-resolution mass spectrometry often employing a reversed phase (RP) column. However, prior to analysis, the contents of these samples are unknown and could be comprised of thousands of known and unknown chemical constituents. Moreover, it is unknown which part of the chemical space is sufficiently retained and eluted using RPLC. Therefore, we present a generic framework that uses a data driven approach to predict whether molecules fall "inside", "maybe" inside, or "outside" of the RPLC subspace. Firstly, three retention index random forest (RF) regression models were constructed that showed that molecular fingerprints are able to predict RPLC retention behavior. Secondly, these models were used to setup the dataset for building a RPLC RF classification model. The RPLC classification model was able to correctly predict whether a chemical belonged to the RPLC subspace with an accuracy of 92% for the testing set. Finally, applying this model to the 91737 small molecules (i.e., <=1000 Da) in NORMAN SusDat showed that 19.1% fall "outside" of the RPLC subspace. Knowing which chemicals are outside of the RPLC subspace can assist in reducing potential candidates for library searching and avoid screening for chemicals that will not be present in RPLC data.
Fabrication of Large Area Metal-on-Carbon Catalytic Condensers for Programmable Catalysis
Authors: Oh Kyung-Ryul , Onn Tzia Ming , Walton Amber , Odlyzko Michael L. , Frisbie C. Daniel , Dauenhauer Paul
Published: September 2023

Catalytic condensers stabilize charge on either side of a high-k dielectric film to modulate the electronic states of a catalytic layer for electronic control of surface reactions. Here, carbon sputtering provided for fast, large-scale fabrication of metal-carbon catalytic condensers required for industrial application. Carbon films were sputtered on HfO2 dielectric/p-type Si with different thickness (1, 3, 6, 10 nm), and the enhancement of conductance and capacitance of carbon films was observed upon increasing carbon thickness following thermal treatment at 400 °C. After Pt deposition on the carbon films, the Pt catalytic condenser exhibited high capacitance of ~210 nF/cm^2 that was maintained at a frequency ~1,000 Hz, satisfying the requirement for a dynamic catalyst to implement catalytic resonance. Temperature programmed desorption of carbon monoxide yielded CO desorption peaks which shifted in temperature with varying potential applied to the condenser (−6 V or 6 +V) indicating a shift in the binding energy of carbon monoxide on the Pt condenser surface. A substantial increase of capacitance (~2,000 nF/cm^2) of the Pt-on-carbon devices was observed at elevated temperatures of 400 °C that can modulate ~10% of charge per metal atom when 10 V potential was applied. A large catalytic condenser of 42 cm^2 area Pt/C/HfO2/Si exhibited high capacitance of 9,393 nF with low leakage current/capacitive current ratio (<0.1), demonstrating the practicality and versatility of the facile, large-scale fabrication method for metal-carbon catalytic condensers.
Deconvolution and Analysis of 1H NMR Spectra of Crude Reaction Mixtures
Authors: Venetos Maxwell , Elkin Masha , Delaney Connor , Hartwig John , Persson Kristin
Published: September 2023

NMR spectroscopy is an important analytical technique in synthetic organic chemistry, but its integration into high-throughput experimentation workflows has been limited by the necessity to manually analyze NMR spectra of new chemical entities. Current efforts to automate the analysis of NMR spectra rely on comparisons to databases of reported spectra for known compounds, and, therefore, are incompatible with the exploration of new chemical space. By reframing the NMR spectrum of a reaction mixture as a joint probability distribution, we have used Hamiltonian Monte Carlo Markov Chain (HMCMC) and density functional theory (DFT) to fit predicted NMR spectra to those of crude reaction mixtures. This approach enables the deconvolution and analysis of spectra of containing mixtures of compounds, without relying on reported spectra. The utility of our approach to analyze crude reaction mixtures is demonstrated with experimental spectra of reactions that generate a mixture of isomers, such as Wittig olefination and C--H functionalization reactions. The correct identification of compounds in a reaction mixture and their relative concentrations is achieved with mean absolute error as low as 1%.
Competing mechanisms determine oxygen redox in doped Ni-Mn based layered oxides for Na-ion batteries
Authors: Li Yongchun , Mazzio Katherine , Yaqoob Najma , Sun Yanan , Freytag Annica , Wong Deniz , Schulz Christian , Baran Volodymyr , San Jose Mendez Alba , Schuck Götz , Zając Marcin , Kaghazchi Payam , Adelhelm Philipp
Published: September 2023

Cation doping is an effective strategy for improving the cyclability of layered oxide cathode materials through suppression of phase transitions in the high voltage region (>~4.0V). In this study we choose Mg and Sc as representative dopants in P2- Na0.67Ni0.33Mn0.67O2. While both dopants have a positive effect on the cycling stability, they are found to influence the properties in the high voltage regime in different ways. Through a combination of RIXS, XRD, XAS, PDF analysis, and DFT, we show that it is more than just suppression of the P2 to O2 phase transition that is critical for promoting the favorable properties, and that the interplay between Ni and O activity are also critical aspects that dictate the performance. With Mg doping, we could enhance the Ni activity while simultaneously suppressing the O activity. This is surprising because it is in contrast to what has been reported in other Mn-based layered oxides where Mg is known to trigger oxygen redox. We address this contradiction by proposing a competing mechanism between Ni and Mg that impacts differences in O activity in Na0.67MgxNi0.33-xMn0.67O2 (x<0<0.33). These findings provide a new direction in understanding the effects of cation doping on the electrochemical behavior of layered oxides.
Quantification and visualisation statistics of Pt cathode degradation via correlative electron and X-ray imaging
Authors: Kang Liqun , Xu Ruoyu , Yan Jay Hon Cheung , Cacho-Nerin Fernando , Parker Juila E. , Allen Christopher S. , Wang Feng Ryan
Published: September 2023

Catalytic degradation in proton exchange membrane fuel cells (PEMFCs) has always been a challenging subject. Despite the monumental research on the subject1-6, the complex relationship between the catalyst deactivation mechanisms and electrochemical degradation remains obscure owing to the heterogenous nature of the catalyst structure. Here we report a correlative electron and X-ray imaging method that enables a multi-modal and multi-length-scale quantification and visualisation of Pt degradation mechanisms in the oxygen reduction reaction (ORR) for proton exchange membrane fuel cell (PEMFC). This technique provides statistical information of up to 107 Pt nanoparticle with 2-dimensional (2D) statistical distribution of Pt content and nanoparticle number in length scales from 2 nm to 20 µm. With the accelerated durability test (ADT) under an O2-saturated 0.1 M HClO4 electrolyte between 0.4 and 1.2 V vs. reversible hydrogen electrode (RHE), the statistical results reveal that the carbon supported Pt nanoparticle catalyst experiences 1) 1:1.5 ratio between the type I degradation mechanisms, Pt dissolution and particle detachment, and type II, Ostwald ripening and particle agglomeration; 2) electrocatalytic activity losses of 33.4% and 41.8% for type I and II degradations, respectively; and 3) macro-scale Pt redistribution from Pt dense regions to sparse regions at an average distance of 1.6 ± 0.9 µm.
A Facile Strategy for Achieving Polymeric Afterglow Materials with Wide Color-Tunability and Persistent Near-infrared Luminescence
Authors: XIONG YU , Chen Keyao , Wang Deliang , Pan Yiwen , Zhao Zheng , Wang Dong , Tang Ben
Published: September 2023

Polymeric afterglow materials with wide color-tunability, efficient near-infrared (NIR) luminescence, and good water solubility are highly desired in various applications but are rarely reported. Herein, a facile but efficient approach is presented to achieve tunable multicolor afterglow and persistent NIR luminescence based on the direct phosphorescence resonance energy transfer (PRET) or sequential resonance energy transfer from the energy donor with ultralong room-temperature phosphorescence to the energy acceptors with red to NIR fluorescence. By simply regulating the doping compositions and concentrations of energy donor/acceptor pairs doped into the poly(vinyl alcohol) (PVA) matrix, the resulting PVA films exhibit persistent multicolor afterglow covering from visible to NIR regions. Notably, compared to the single-step PRET, the two-step sequential resonance energy transfer has the unique advantages of higher transfer efficiency of triplet excitons from the initial donor, a wider range of color-tunability mediated by the intermediary acceptor, and enhanced delayed fluorescence efficiency of the final acceptor. By preparing water-soluble PVA films with different doping compositions and concentrations, we demonstrate their great potential applications in advanced anti-counterfeiting and information encryption. This work provides a facile strategy for the exploration of polymeric afterglow materials with excellent color-tunability and efficient NIR delayed fluorescence, which can further help to expand the practical applications of organic afterglow materials.
Ring Opening Polymerization and Copolymerization for Polyester and Polycarbonate Formation by a Diamino-bis(phenolate) Chromium(III) Catalyst
Authors: Vos Cyler , Beament James , Kozak Christopher
Published: September 2023

The diamino-bis(phenolate) chromium(III) complex, CrCl[L], 1 where [L] = dimethylaminoethylamino-N,N-bis(2-methylene-4,6-tert-butylphenolate) when pre-contacted with cocatalyst, bis(triphenylphosphine)iminium chloride, formed the bis(triphenylphosphine)iminium chromium(III) dichloride ate complex, 2. Complex 2 shows good activity for the ring-opening polymerization (ROP) of rac-lactide (rac-LA) and -caprolactone (-CL), ring-opening copolymerization (ROCOP) of cyclohexene oxide (CHO) and phthalic anhydride (PA), ROCOP of epoxides and CO2, and synthesis of terpolymers containing polylactide or polycaprolactone, polycarbonate, and polyester segments. For example, polyester-b-polycarbonates can be obtained through controlled ROCOP of PA and CHO giving, moderate molecular weight polymers with narrow dispersity (e.g. Mn = 8.7 kg mol-1 and Đ = Mw/Mn = 1.14), followed by addition of CO2 to generate polycarbonate chains and an increase in Mn to 17.6 kg mol-1 with Đ = 1.13.
Comparative analysis of bioinformatics tools to characterize SARS-CoV-2 subgenomic RNAs
Authors: Lavezzari Denise , Mori Antonio , Pomari Elena , Deiana Michela , Fadda Antonio , Bertoli Luca , Sinigaglia Alessandro , Riccetti Silvia , Barzon Luisa , Piubelli Chiara , Delledonne Massimo , Capobianchi Maria Rosaria , Castilletti Concetta
Published: September 2023

During the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), positive-sense genomic RNA and subgenomic RNAs (sgRNAs) are synthesized by a discontinuous process of transcription characterized by a template switch, regulated by transcription-regulating sequences (TRS). Although poorly known about makeup and dynamics of sgRNAs population and function of its constituents, next-generation sequencing approaches with the help of bioinformatics tools have made a significant contribution to expand the knowledge of sgRNAs in SARS-CoV-2. For this scope to date, Periscope, LeTRS, sgDI-tector, and CORONATATOR have been developed. However, limited number of studies are available to compare the performance of such tools. To this purpose, we compared Periscope, LeTRS, and sgDI-tector in the identification of canonical (c-) and noncanonical (nc-) sgRNA species in the data obtained with the Illumina ARTIC sequencing protocol applied to SARS-CoV-2–infected Caco-2 cells, sampled at different time points. The three software showed a high concordance rate in the identification and in the quantification of c-sgRNA, whereas more differences were observed in nc-sgRNA. Overall, LeTRS and sgDI-tector result to be adequate alternatives to Periscope to analyze Fastq data from sequencing platforms other than Nanopore.
revenues of the territorial community of the city
Authors: Tkachuk N.
Published: September 2023

The study is devoted to the consideration of practical aspects of the analysis of the formation of the budget of the territorial community of the city. It is emphasized that an important role in the system of ensuring the sustainable development of territorial communities today is assigned to the mechanism of ensuring their financial capacity, the successful functioning of which makes it possible not only to prevent a financial crisis, but also to a large extent to rid the territory of the dependence on the use of the involved financial resources, to accelerate the pace of their sustainable development . The financial capacity of the territorial community of the city today is determined by the efficiency of the revenue generation of the corresponding local budget. The author focused attention on the need for a detailed, comprehensive analysis of the formation of the budget of the territorial community of Khmelnytskyi based on the study of the level of implementation of revenues in terms of general and special budget funds. The structural structure of the territorial community's budget revenues was appropriately analyzed according to the main sources of their formation according to the Budget Code of Ukraine: tax revenues, non-tax revenues, revenues from capital transactions and official transfers. An assessment of the dynamics of sources of revenue formation of the territorial community budget of Khmelnytskyi for 2017-2021 is provided. The work revealed that the main source of revenue formation of the studied local budget is tax revenue. Therefore, the author analyzed the structure of tax revenues of the city's territorial community budget and tracked their dynamics in terms of direct and indirect tax revenues. Taking into account the transfer of significant functions of the state to the local level, such sources of income formation of the territorial community's budget as interbudgetary transfers (subsidies and subventions), the dynamics and structure of which have been studied by the author for 2017-2021, become important. It is noted that a detailed analysis of the income formation of the territorial community's budget makes it possible to identify potentially important sources of income increase in order to fully finance the needs of the territorial community of the city in the provision of socially necessary services.
Method of calculating the integral indicator of transparency of Ukrainian banks
Authors: Oleksich Z. , Yaroshyna A.
Published: September 2023

The research is devoted to the problem of financial and non-financial information disclosure by banking groups of Ukraine. Detinization of the economy is one of the highest priorities of state policy, banks, as the largest group of financial intermediaries, act as one of the tools to reduce the level of shadow transactions. However, the problem of the presence of mechanisms for identifying violations, anti-corruption measures, which in turn should have a positive effect on the level of bank transparency, is still not sufficiently covered. In this paper authors analyze the Management Report. It is a report, which contains financial and non-financial information, reveals the state and prospects of development, and characterizes the key risks accompanying the activity. Since at this stage the normative acts do not define a unified form, the problem of information disclosure is quite urgent. Taking into account the above-mentioned research problems, the authors analyzed the key structural divisions of the Report of the largest state-owned banks with private and foreign capital during 2021-2022. Using the expert method, the points of the Report that more fully disclose information, those that directly relate to the problem of shadowing, were determined economy and fight against corruption, and those that do not exist at all. As the next stage, the authors chose the Fishburne method for ranking indicators in order of their importance, which became the basis for deriving an integral indicator of transparency for each bank. The results show that there is a general tendency to increase the level of openness of financial and non-financial information of banks. In terms of forms of ownership, banks with foreign capital and state-owned banks are more transparent, which in turn helps to reduce the level of shadow transactions.
The role of educational institutions in the development of startup ecosystems (on the example of Lviv)
Authors: Mazur A.
Published: September 2023

Educational institutions are active participants in the startup ecosystem, they create conditions for the development of startup ideas based on higher education institutions and in cooperation with international partners and businesses. The article analyzes the activities of the universities of the city of Lviv, namely Lviv Polytechnic National University, Ukrainian Catholic University, and Ivan Franko Lviv National University in the direction of startups. Universities have high rankings in the international rankings QS World University Rankings, Top 50 Universities in Europe for Startups, Top Universities for Startups in Europe by Educations.com, and U-Multirank World University Rankings, which indicates a strong direction of support and expansion of opportunities for entrepreneurial education. The Lviv Polytechnic National University and the Ukrainian Catholic University created the most groundwork for the creation of a startup environment in the Lviv region. The UCU Entrepreneurship Center, accelerator programs, and Tech StartUp School at the Lviv Polytechnic operate at higher education institutions, which actively promote the implementation of startup ideas among student youth. At the Lviv National University named after I. Franko, innovative bachelor's programs are implemented in partnership with the Lviv IT cluster, and annual start-up events are held, in the framework of which technology transfer takes place, foreign investors are invited and presentations of student start-ups are held. A survey conducted among students who chose the discipline of free choice "Start-up management" showed that a significant majority of students agreed that such a course is important for the development of their professional competence, practical, and relevant to the modern realities of the economy. The course structure, which included lectures, guest lectures, and practical sessions, was recognized by students as useful for developing knowledge and skills in the field of entrepreneurship and startups. In addition, the student's expectations from the course were mostly fulfilled, and the course motivated a significant part of the students to continue working on the startups they created. However, during remote group work, some difficulties arose, which affected the effectiveness of teamwork. The development of a start-up environment based on institutions of higher education allows students to develop entrepreneurial skills that they can apply in the real world. By creating a startup, students can learn to identify and solve real-world problems, work collaboratively in teams, and develop a range of entrepreneurial skills such as creativity, innovation, and risk-taking.