bluuebunny/crossref_metadata_2025 huggingface dataset:
Zirconia-supported Pt, Pd, Rh, Ru and Ni catalysts in the hydrotreatment of fatty amides and amines
Authors: Verkama Emma , Albersberger Sylvia , Meinander Kristoffer , Tiitta Marja , Karinen Reetta , Puurunen Riikka L.
Published: January 2024

Active catalysts for simultaneous hydrodeoxygenation (HDO) and hydrodenitrogenation (HDN) enable the production of fuels from renewable feedstocks. In this work, zirconia-supported nickel, ruthenium, rhodium, palladium and platinum catalysts were evaluated in the HDO and HDN of n-hexadecanamide (C16 amide). The HDN of 1-hexadecylamine (C16 amine) was studied separately to assess the HDN activity and preference between C–C and C–N bond cleavage routes without the interference of HDO. The differences in the catalytic activity were mainly attributed to the metal identity. Pt/ZrO2 and Ru/ZrO2 exhibited the highest activity towards the conversion of both model compounds. The C16 amide was converted more efficiently than the C16 amine over the studied catalysts, and a high HDO activity did not translate to a high activity in HDN, which was particularly evident in the case of Rh/ZrO2. The active metal strongly influenced the preferred reaction routes, as observed from differences in the yields of C15 and C16 n-paraffins and C32 condensation products. Ni/ZrO2 and Pd/ZrO2 exhibited the lowest activity and paraffin selectivity in the hydrotreatment of both model compounds. Ru/ZrO2 and Rh/ZrO2 favored the formation of n-pentadecane from both the C16 amine and C16 amide, whereas Pt/ZrO2 produced n-hexadecane and high intermediate yields of the C32 condensation products.
Endergonic synthesis driven by chemical fuelling
Authors: Olivieri Enzo , Gallagher James M. , Betts Alexander , Mrad Toufic W. , Leigh David A.
Published: January 2024

Spontaneous chemical reactions proceed energetically downhill to either a local or global minimum, limiting possible transformations to those that are exergonic. Endergonic reactions do not proceed spontaneously and require an input of energy. Light has been used to drive a number of deracemisations and thermodynamically unfavourable bond-forming reactions, but is restricted to substrates that can absorb, directly or indirectly, energy provided by photons. In contrast, anabolism involves energetically uphill transformations powered by chemical fuels. Here we report on the transduction of energy from an artificial chemical fuel to drive a thermodynamically unfavourable Diels–Alder reaction. Carboxylic acid catalysed carbodiimide-to-urea formation is chemically orthogonal to the reaction of the diene and dienophile, but transiently brings the functional groups into close proximity, causing the otherwise prohibited cycloaddition to proceed in modest yield (15% after two fuelling cycles) and with high levels of regio- (>99%) and stereoselectivity (92:8 exo:endo). Kinetic asymmetry in the fuelling cycle ratchets the Diels–Alder reaction away from the equilibrium distribution of the Diels–Alder:retro-Diels–Alder products. The driving of the endergonic reaction occurs through a ratchet mechanism (an energy or information ratchet, depending on the synthetic protocol), reminiscent of how molecular machines directionally bias motion. Ratcheting synthesis has the potential to expand the synthetic chemistry toolbox, offering new paradigms in reactivity, complexity and control.
A global view of T cell metabolism in Systematic Lupus Erythematosus
Authors: Goetz Andrew , Morel Laurence , Dixit Purushottam
Published: January 2024

Impaired metabolism is recognized as an important contributor to pathogenicity of T cells in Systemic Lupus Erythematosus (SLE). Over the last two decades, we have acquired significant knowledge about the signaling and transcriptomic programs related to metabolic rewiring in healthy and SLE T cells. However, our understanding of metabolic network activity derives largely from studying metabolic pathways in isolation. Here, we argue that enzymatic activities are necessarily coupled through mass and energy balance constraints with in-built network-wide dependencies and compensation mechanisms. Therefore, metabolic rewiring of T cells in SLE must be understood in the context of the entire network, including changes in metabolic demands such as shifts in biomass composition and cytokine secretion rates as well as changes in uptake/excretion rates of multiple nutrients and waste products. As a way forward, we suggest cell physiological experiments and integration of orthogonal metabolic measurements through computational modeling towards a comprehensive understanding of T cell metabolism in lupus.
tert-Butyl as a Functional Group: Non-Directed Catalytic Hydroxylation of Sterically Congested Primary C−H Bonds
Authors: Chan Siu-Chung , Palone Andrea , Bietti Massimo , costas Miquel
Published: January 2024

The tert-butyl group is a common aliphatic motif extensively employed to implement steric congestion and conformational rigidity in organic and organometallic molecules. Because of the combination of a high bond dissociation energy (~ 100 kcal mol-1) and limited accessibility, in the absence of directing groups, neither radical nor organometallic approaches are effective for the chemical modification of tert-butyl CH bonds. Herein we overcome these limits by employing an electron-poor manganese catalyst that operates in the strong hydrogen bond donor solvent nonafluoro-tert-butyl alcohol (NFTBA) and catalytically activates hydrogen peroxide to generate a powerful manganese-oxo species that effectively oxidizes tert-butyl C−H bonds. Leveraging on the interplay of steric, electronic, medium and torsional effects, site-selective and product chemoselective hydroxylation of the tert-butyl group is accomplished with broad reaction scope, delivering primary alcohols as largely dominant products in preparative yields. Late-stage hydroxylation at tert-butyl sites is demonstrated on 6 densely functionalized molecules of pharmaceutical interest. This work uncovers a novel disconnection approach, harnessing tert-butyl as a potential functional group in strategic synthetic planning for complex molecular architectures.
Evaluation of Ketoclomazone and its Analogues as Inhibitors of Thiamine Diphosphate (ThDP)-dependent Enzymes
Authors: Chan Alex H. Y. , Ho Terence C. S. , Fathoni Imam , Hamid Rawia , Hirsch Anna K. H. , Saliba Kevin J. , Leeper Finian James
Published: January 2024

Most pathogenic bacteria, apicomplexan parasites and plants rely on the methylerythritol phosphate (MEP) pathway to obtain precursors of isoprenoids. 1-Deoxy-D-xylulose 5-phosphate synthase (DXPS), a thiamine diphosphate (ThDP)-dependent enzyme, catalyses the first and rate-limiting step of the MEP pathway. Due to its absence in humans, DXPS is considered as an attractive target for the development of anti-infectious agents and herbicides. However, major challenges in designing therapeutic agents that target DXPS include: a) discovering drug-like inhibitors to occupy a highly polar active site; and b) selectively targeting DXPS over other ThDP-dependent enzymes. Ketoclomazone is one of the earliest reported inhibitors of DXPS and antibacterial and herbicidal activities have been documented. This study aimed to investigate the activity of ketoclomazone on DXPS from various species, as well as the broader ThDP-dependent enzyme family. To gain further insights into the inhibition, we have prepared analogues of ketoclomazone and evaluated their activity in biochemical and computational studies. Our findings support the potential of ketoclomazone as a selective antibacterial agent.
Tris-Azo Triangular Paraphenylenes: Synthesis and Reversible Interconversion into Radial π-Conjugated Macrocycles
Authors: Ide Tomohito , Huang Wei-Ci , Horie Masaki
Published: January 2024

We report the synthesis of cycloparaphenylene derivatives featuring tris-azo groups. The smaller derivative, [3]cycloazobenzene ([3]CAB-0), adopts a triangular all-cis form and exhibits thermally and photochemically stable characteristics due to significant ring strain, as well as symmetric Kagome-patterned crystal packing. In contrast, the as-synthesized [3]cycloazobenzene with three biphenylene bridges ([3]CAB-1) adopts a similar triangular all-cis form; however, it undergoes photoinduced isomerization, leading to a mixture of cis and trans forms at a photostationary state. Interestingly, the addition of an excess of acid selectively leads to the formation of the all-trans form. DFT calculations reveal that the interconversion from a triangular to a circular shape correlates with an increase in HOMO and a decrease in LUMO, characteristics intrinsic to radial π-conjugated systems.
Biotin-Initiated Poly(Oxazoline)s
Authors: Garcia Joseph , Vergara Mendez Ashley , Sletten Ellen
Published: January 2024

Biotinylated hydrophilic polymers are used in a plethora of chemical and biochemical assays due to the exceptional affinity of biotin for (strept)avidin. Here we report a facile method for the installation of biotin at the end of poly(oxazoline)s (P(Ox)) using an electrophilic biotin initiator. While this method is applicable to many different oxazoline monomers, we focus on biotin-poly(2-methyl-2-oxazoline) as it is a desirable alternative to poly(ethylene glycol) (PEG), which has rising immunogenicity concerns. A further advantage of POx over PEG is the high degree of chemical flexibility that can be imparted, which we showcase through the preparation of varied molecular weight, amphiphilic, and bifunctional POxs. Furthermore, we demonstrate the high efficacy of these biotin polymers through a series of common biochemical assays that frequently utilize the biotin-streptavidin pair.
Revealing the Role of Redox Reaction Selectivity and Mass Transfer in Current–Voltage Predictions for Ensembles of Photocatalysts
Authors: Barrera Luisa , Esposito Daniel , Ardo Shane , Bala Chandran Rohini
Published: January 2024

Photocatalysts are conceptually simple reaction units where nanoscale semiconductors integrated with catalysts drive a pair of redox reactions on illumination. However, the proximity of reaction sites performing cathodic and anodic reactions poses dire challenges to realize large light-to-fuel conversion efficiencies. In this study, a powerful, yet straightforward, equivalent-circuit detail-balance modeling framework is developed and applied to evaluate the performance of photocatalytic systems featuring multiple light absorbers. Specifically, low bandgap iridium-doped strontium titanate is modeled a Z-scheme photocatalyst to effect desired hydrogen evolution and iron-based redox shuttle oxidation reactions. Our model has unique capabilities to simulate competing redox reactions and address mass-transfer limitations. In a significant departure from state-of-the-art circuit models, our study develops tools to perform load-line analyses by incorporating a net electrochemical load curve that includes both desired and competing redox reactions. Consequently, reaction selectivity is predicted from equivalent circuit models for photocatalytic and photoelectrochemical systems. Our investigation into ensembles comprised of multiple, semi-transparent light absorbers reveals their potential to outperform a single, optically thick light absorber, particularly when operated under mass-transfer-limited conditions. However, this outcome hinges on minimizing mass-transfer rates of select redox species to prevent undesired reactions of hydrogen oxidation and/or redox shuttle reduction. Our findings demonstrate that reaction selectivity can be achieved by tuning asymmetry in redox species mass-transfer even with perfectly symmetric electrocatalytic charge-transfer coefficients. The influences of various kinetic, mass-transfer, and thermodynamic parameters are explored to offer crucial insights to inform the next-generation of photocatalysts, selective coatings, and reactor designs.
A simple periodic peptide derived from Pinctada fucata Pif80 protein induces aragonite nucleation in magnesium absence
Authors: Tah Bidisha , Berman Amir , Upcher Alexander
Published: January 2024

Pif80 protein is associated with nacre formation in the Akoya pearl oyster. The influence of Pif2, a 32-mer peptide derived from Pif80, on calcium carbonate polymorphism, crystal orientation, morphology, and the induction of aragonite was investigated. X-ray diffraction (XRD) analyses reveal that Pif2, in the presence of a polydiacetylene (PDA) template, enhances calcite crystal nucleation on the (012) plane while suppressing the nucleation from the (104) face. Scanning electron microscopy (SEM) images illustrate the Pif2 concentration-dependent impact on calcite crystal morphology, with higher concentrations leading to deformed habits and distinct crystal faces. The peptide induces aragonite formation, even under conditions conducive to calcite growth, as evidenced by SEM and transmission electron microscopy (TEM) studies, on the condition that an appropriate template is provided. Time-dependent SEM observations trace the transformation of amorphous calcium carbonate to calcite/aragonite, highlighting Pif2's role in this process. Experiments with geological aragonite templates affirm the preferential formation of aragonite in the presence of Pif2, as confirmed by TEM and focused ion beam scanning electron microscopy (FIBSEM) analyses. The results underscore Pif2's pivotal role in orchestrating the biological control of polymorphism in Pinctada fucata, providing valuable insights for biomineralization studies and biomimetic materials design.
Revisiting the Reactivity of the Dismissed Hydrogen Atom Transfer Catalyst Succinimide-N-oxyl
Authors: Yang Cheng , Farmer Luke , Pratt Derek , Maldonado Stephen , Stephenson Corey
Published: January 2024

Phthalimide-N-oxyl (PINO) and related radicals are promising catalysts for C-H functionalization reactions. To date, only a small number of N-oxyl derivatives have demonstrated improved activities over PINO. We postulate that the lack of success in identifying superior catalysts is associated not only with challenges in the design and synthesis of new structures, but also the way catalysts are evaluated and utilized. Catalyst evaluation typically relies on the use of chemical oxidants to generate N-oxyl radicals from their parent N-hydroxy compounds. We put forth an example where a potential-controlled electrochemical analy-sis reveals that succinimide-N-oxyl (SINO) compares favorably to PINO as a hydrogen atom transfer catalyst – in contrast to previous claims based on other approaches. Furthermore, our efforts to understand the basis for the greater reactivity of SINO relative to PINO have shed further light on the interplay of thermodynamic and kinetic factors in these HAT reactions and sug-gest that transition state (TS) polarization is a particularly important consideration. This is illustrated by the essentially identi-cal reactivity of tetrachloro-PINO and SINO despite the significantly greater thermodynamic driving force in the reactions of the latter. Such measures of HAT TS polarization (i.e., proton affinity of the N-oxide anion) may be useful parameters in pre-dicting and/or rationalizing reactivity in addition to reaction energetics (i.e., O-H bond dissociation enthalpy of the N-OH moie-ty). Building on these insights, we report the design and initial characterization of a chlorinated SINO derivative that has signif-icantly greater reactivity as a HAT catalyst than either PINO or its chlorinated derivative.
Soldier health and position monitoring system using GPS and IOT technology
Authors: Bhavani R. , Nithyasri C.
Published: January 2024

The fighter Wellbeing and Position Global Positioning Framework allows the military to track the current GPS position of officers and also monitors their health status, including internal temperature and heartbeat. This system also includes an additional feature that enables a soldier to request physical assistance or send a distress signal to the military if needed. The GPS modem transmits the latitude and longitude positions in a connected pattern, aiding the military in tracking the officer's current location. The system is highly beneficial for obtaining real-time health status information and providing immediate assistance to soldiers. In today's world, all nations prioritize their security, and soldiers, as the backbone of any armed forces, often lose their lives due to lack of medical aid during emergencies. Furthermore, soldiers engaged in missions or special operations might become disoriented on war fields, losing contact with authorities. To address these concerns, we developed this project. By utilizing a Wireless Body Area Sensor Network (WBANS) consisting of temperature and heartbeat sensors, we can monitor the soldiers' health status whenever necessary. Additionally, through GPS, we can track the precise location of the soldiers as needed. The use of an oxygen level sensor enables us to monitor the environmental conditions so that necessary aid can be provided by medical professionals. Communication between the soldiers and medical personnel is established via the Internet of Things (IoT). Any anomalies detected by the Remote Body Area Sensor Network (WBASNs) act as triggers for the IoT device to establish a connection between the soldier and the base unit, transmitting current location and health status to the receiver. To effectively convey this data, we have employed this equipment to create a cost-effective, lightweight, portable, and accurate defense system for soldiers.
Bilangan Kromatik Modular Beberapa Kelas Graf Planar
Authors: Ambarwati Sukma Kusuma , Budayasa I Ketut
Published: January 2024

Misalkan graf tanpa titik terasing. Titik  pada graf ,  merupakan persekitaran titik . Jumlah warna  pada  di  didefinisikan sebagai jumlah warna di , yaitu  (mod ). Pewarnaan modular pada  adalah sebuah fungsi , dengan  dimana  dalam  untuk semua pasang titik  dan  yang berhubungan langsung pada . Bilangan kromatik modular  adalah minimum  dimana ada pewarnaan-  modular pada  yang dilambangkan dengan . Pada artikel ini dijelaskan tentang batas atas dan batas bawah dari bilangan kromatik modular suatu graf dan bilangan kromatik modular pada beberapa kelas graf planar yaitu graf Sikel , graf Pohon , graf Roda  dan join dua graf .

Kata Kunci: Pewarnaan modular, Bilangan kromatik modular, Graf Pohon, Graf Sikel, Graf Roda.
PEMODELAN MATEMATIKA OPSI SAHAM KARYAWAN YANG MEMPERTIMBANGKAN EFEK DILUSI
Authors: Taufiqi Nuril Hidayah , Artiono Rudianto
Published: January 2024

Opsi saham yang digunakan oleh para perusahaan untuk penghargaan bagi karyawannya, yang dinamakan Opsi Saham Karyawan (Employee Stock Option), yang selanjutnya disingkat OSK, secara definisi diartikan sebagai pilihan kompensasi yang ditawarkan perusahaan kepada karyawan berupa opsi untuk membeli saham/opsi call di harga tertentu dan dalam jangka waktu yang telah ditentukan. Dalam pengimplementasiannya, terdapat efek dilusi yang diakibatkan dari adanya OSK ini. Efek dilusi terjadi ketika suatu perusahaan menerbitkan saham tambahan dan melepasnya ke pasar, sehingga meningkatkan jumlah saham yang beredar. Hal ini dapat berdampak pada harga saham perusahaan, karena adanya penambahan pasokan saham yang tersedia di pasar. Perhitungan nilai opsi dapat dilakukan dengan berbagai metode. Salah satu metode untuk memodelkan nilai opsi adalah menggunakan persamaan diferensial Black-Scholes. Solusi analitik dari persamaan diferensial tersebut menjadi model untuk perhitungan harga opsi. Adapun model dari harga opsi saham karyawan terdilusi adalah:

 

Berdasarkan model ini dilakukan pehitungan pada suatu close price saham x periode 30 Mei 2022 – 30 Mei 2023 dengan harga saham awal 9050 dan harga kesepakatan 4982, tingkat suku bunga 5,75%, volatilitas saham 23,84%, jumlah saham yang beredar ( yakni sebanyak 18.462.169.893 waktu jatuh tempo dari saham, laju karyawan meninggalkan perusahaan 1% dan banyaknya OSK yang diberikan perusahaan (θ) sebanyak 35.349.718. Simulasi dilakukan dengan metode analitik dan Phyton. Diperoleh nilai opsi saham karyawan terdilusi dari saham tersebut sebesar 2547.17. Adapun perhitungan pengaruh parameter dan dengan menggunakan Python menunjukkan bahwa peningkatan jumlah saham perusahaan yang beredar meningkatkan harga OSK tetapi peningkatan jumlah OSK yang beredar akan menurunkan harga OSK
ANALISIS KESTABLAN MODEL MATEMATIKA KECANDUAN PORNOGRAFI DI KALANGAN PELAJAR DAN MAHASISWA
Authors: Ramadani Ardian Nugraha , Maulana Dimas Avian
Published: January 2024

Internet yang menjadi sarana komunikasi dan interaksi yang utama bagi masyarakat dari berbagai kalangan telah membawa banyak perubahan dalam kehidupan sehari-hari manusia. Selain memberikan dampak positif, internet juga membawa dampak negatif terutama bagi perkembangan dan pertumbuhan otak remaja dan anak-anak terkait dengan masalah pornografi. Efek paparan yang paling banyak dirasakan adalah adiksi atau kecanduan. Kecanduan pornografi adalah perilaku yang tidak normal dimana seseprang mengalami kepuasasn seksual yang lebih banyak melalui literatur dan gambar-gambar pornografi. Pada penelitian ini akan direkonstruksi model matematika kecanduan pornografi dengan membagi menjadi empat populasi, yaitu individu yang rentan terhadap pornografi (S), individu yang terpapar pornografi (E), individu yang kecanduan pornografi (A), dan individu yang sembuh dari kecanduan pornografi (R). Berdasarkan model yang sudah direkonstruksi maka dihasilkan dua titik kesetimbangan, yaitu titik kesetimbangan bebas kecanduan dengan nilai Z0 = (m/k;0;0;0) dan titik kesetimbangan endemik dengan nilai Z1 = (5,24; 1,55; 0,08; 20,4) selanjutnya dengan menuntukan bilangan reporoduksi dasar (R0) dengan menggunakan Next Generation Matrix (NGM) dengan nilai  dan mengalisis kestabilannya menggunakan nilai eigen dan kestabilan Routh-Hurwitz. Titik Kesetimbangan bebas kecanduan bersifat stabil asimtotik jika dan hanya jika R0<1, sedangkan titik kesetimbangan endemik bersifat stabil asimtotik jika dan hanya jika R0>1. Dilakukan simulasi numerik menggunakan python dengan nilai awal dan parameter dari data yang diambil dari kuisioner online. Hasil dari simulasi numerik didapatkan bahwa pada model kecanduan pornografi di kalangan pelajar dan mahasiswa terjadi endemik dengan nilai.R0=1,36.
ANALISIS SENSITIVITAS SOLUSI OPTIMAL PADA INTEGER LINEAR PROGRAMMING DI PERUSAHAAN ROTI LYLY BAKERY LAMONGAN
Authors: Khoirunnisa Dinah Roidah , Astuti Yuliani Puji
Published: January 2024

Perusahaan Lyly Bakery adalah salah satu perusahaan produksi dan pemasaran berbagai jenis roti di Kabupaten Lamongan. Adapun masalah yang dihadapi yaitu dengan tingkat persaingan yang tinggi, perusahaan belum memiliki perhitungan atau rancangan untuk jumlah produk yang harus diproduksi dengan mengestimasi ketersediaan bahan baku yang ada agar memperoleh keuntungan maksimum. Metode yang digunakan dalam penelitian ini yaitu metode Branch And bound yang dilanjutkan dengan melakukan analisis sensitivitas terhadap fungsi tujuan dan ruas kanan pembatas untuk mengetahui batas toleransi mengenai perubahan yang terjadi agar solusi tetap optimal. Metode Branch and Bound merupakan pendekatan yang paling efektif dalam menyelesaikan permasalahan integer linear programming dibanding dengan metode lainnya. Solusi optimal yang diperoleh yaitu perusahaan Lyly Bakery Lamongan memproduksi untuk donat 900 buah, 180 buah pastry croissant, 115 puff pastry, 125 buah tawar, 130 buah roti ban, 75 buah cupcake, 970 buah bolu slice, 130 buah soes, 160 buah brownies, 60 buah pudding, 80 buah muffin, 35 buah tart, 900 bakery kecil, dan 1259 buah bakery besar dengan keuntungan yang diperoleh yaitu Rp.19.558.180. Hasil analisis sensitivitas menunjukan bahwa keuntungan akan tetap maksimum dengan jumlah produksi akan tetap optimal apabila perubahan koefisien fungsi tujuan dan ruas kanan tetap berada pada interval yang telah didapatkan melalui perhitungan dengan bantuan software QM for Windows V5. Salah satu hasil analisis sensitivitas produk donut memiliki batas ditolerir batas atas untuk perubahan fungsi tujuan yaitu Rp.1082 dan batas bawah Rp1.016 serta hasil analisis sensitivitas terhadap ruas kanan untuk kapasitas tepung terigu memiliki batas bawah 224.651,5 gram dan batas atas 233.370,2 gram.
Perbandingan Model Feed Forward Neural Network dan ARIMA untuk Meramalkan Perkembangan COVID-19 di Indonesia
Authors: Aminy Laily Nadiyah , - Walid
Published: January 2024

Penyebaran pandemi novel coronavirus disease (COVID-19) di Indonesia menjadi perhatian besar bagi pemerintah, masyarakat, dan peneliti. Kajian ini membandingkan dua model peramalan yaitu, Feed Forward Neural Network (FFNN) dan Autoregressive Integrated Moving Average (ARIMA), untuk meramalkan perkembangan COVID-19 di Indonesia. Adapun studi ini bertujuan untuk mengetahui Model ARIMA pada peramalan kasus perkembangan COVID-19 di Indonesia, untuk mengetahui Model FFNN pada peramalan kasus perkembangan COVID-19 di Indonesia, serta untuk mengetahui perbandingan hasil peramalan Model ARIMA dan FFNN pada kasus perkembangan COVID-19 di Indonesia. Metode penelitian yang digunakan yaitu metode analisis deskriptif kuantitif pada data kasus harian COVID-19 di Indonesia. Hasil penelitian menunjukkan bahwa kedua model peramalan tersebut memiliki kinerja yang cukup untuk meramalkan evolusi COVID-19 di Indonesia. Secara umum, model FFNN memberikan hasil peramalan yang lebih akurat dan lebih baik daripada model ARIMA. Secara keseluruhan, temuan ini mengindikasikan bahwa model FFNN memiliki performa tingkat akurasi yang lebih baik dalam peramalan kasus harian COVID-19 di Indonesia. Dengan demikian, mempertimbangkan pilihan model yang sesuai dengan karakteristik data dan tujuan peramalan akan menjadi langkah penting dalam usaha untuk meramalkan perkembangan COVID-19 dengan lebih akurat di masa yang akan datang.
OPTIMASI METODE JARINGAN SARAF TIRUAN BACKPROPAGATION UNTUK PERAMALAN CURAH HUJAN BULANAN DI KOTA DENPASAR
Authors: Nailah Fadia , Larasati Dwi Ina , Siswanto Siswanto , Kalondeng Anisa
Published: January 2024

Rainfall is a natural phenomenon that depends on many factors that are an important part of life on earth. The high intensity of rainfall can lead to disasters. Therefore, this study aims to forecast monthly rainfall. The data used was obtained from BMKG Bali Province, namely monthly rainfall data for Denpasar City from 2009 to 2019. The method used is backpropagation artificial neural network. The artificial neural network method is an information processing method inspired by the human nervous system. Optimal backpropagation network architecture is needed so that the prediction results have a low error rate, by optimizing the use of training data and test data taken from sample data. Based on the results of the testing and prediction process with the parameters of one hidden layer with 50 neorons, epoch 11 and learning rate 0.01, the results obtained with the MSE value in network testing are 0.037. So it can be concluded that the backpropagation artificial neural network method has good accuracy results used as a reference for decision making in predicting monthly rainfall in Denpasar City in the future.
GRAF BERARAH SEBAGAI REPRESENTASI TURNAMEN "ROUND-ROBIN" DAN SIFAT-SIFATNYA
Authors: Nugroho Dimas , Budayasa Ketut
Published: January 2024

Graf berarah D adalah pasang berurutan dari dua himpunan V(D) dan Γ(D), yaitu himpunan berhingga tak kosong yang anggota-anggotanya disebut titik dan himpunan berhingga (boleh kosong) yang anggota-anggotanya disebut busur sedemikian hingga setiap busur merupakan pasang berurutan dari dua titik V(D). Turnamen adalah orientasi dari graf komplet. Sebuah turnamen dapat dimodelkan atau direpresentasikan dengan sebuah graf berarah yang himpunan timnya berkorespondensi dengan himpunan titik pada graf berarah, dan dua titik u dan v dihubungkan dengan sebuah busur dari u ke v, jika dan hanya jika tim yang diwakili oleh titik u mengalahkan tim yang diwakili oleh titik v. Dengan demikian turnamen Round-Robin dapat direpresentasikan dengan graf berarah yang graf dasar adalah graf komplet

Kata kunci: Graf Berarah, Graf Komplet, Graf Dasar, Orientasi Graf, Busur, Turnamen Round-Robin
PENERAPAN INTEGER LINEAR PROGRAMMING DAN ANALISIS SENSITIVITAS PADA OPTIMALISASI PRODUK USAHA KUE PUTU ASLI M*R
Authors: Nahda Atika , Granita Granita
Published: January 2024

Bisnis Kue Putu Asli M*R adalah usaha Kue yang menciptakan 3 varian, yakni putu pangggang putih,panggang hitam, serta kukus. Bisnis ini Terletak di Balingka, Kecamatan IV Koto, Kabupaten Agam, Sumbar.Metode penelitian ini adalah metode replikasi yang merupakan replikasi dari penelitian terdahulu. Riset inimempunyi sasaran melakukan perhitungan pembuatan memanfaatkan metode branch and bound sertamengevaluasi variasi yang bisa diterapkan pada aspek aspek pembuatan melalui analisis sensitivitas. Metodebranch and bound adalah suatu metode yang paling efektive saat menyelesaikan fenomena program linear dibanding metode lainnya. Berdasarkan perhitungan diperoleh solusi optimal yaitu dengan memproduksiputu panggang putih sebanyak 9950, panggang hitam sebanyak 4820. Dan kukus sebanyak 2795. Sedangkanhasil Analisis sensitivitas memperlihatkan ketika terjadi pergantian pada aspek pembuatan dalam jangkamaksimal; dan minimal, hal tersebut akan menahan penyelesaian terhadap koefisien sasaran dan angka batasguna hambatan.
IMPLEMENTASI DIMENSI FRAKTAL BOX COUNTING DAN K-MEANS DALAM KLASIFIKASI JENIS IKAN LAUT BERDASARKAN CORAK TUBUH
Authors: Faizah Ayu Mazidatul , Juniati Dwi
Published: January 2024

Ikan adalah kelompok hewan bertulang belakang (vertebrata) yang hidup di dalam air, bernapas melalui insang, dan memiliki sirip untuk berenang. Dalam taksonomi, ikan masuk dalam kelompok paraphyletic. Ikan berperan penting dalam ekosistem perairan dan juga menjadi makanan pokok bagi banyak masyarakat di muka bumi ini. Selain dilihat dari bentuk tubuh, ekor, dan bentuk siripnya, corak pada tubuh ikan juga berperan penting dalam mengidentifikasi jenis ikan. Dalam matematika, gagasan mengenai fraktal adalah salah satu metode yang cocok untuk memahami pola atau bentuk yang tidak beraturan pada suatu objek. Dalam penelitian ini, dilakukan pengklasifikasian ikan laut berdasarkan corak pada tubuhnya menggunakan dimensi fraktal. Sebanyak 120 citra berwarna pada bagian tengah tubuh ikan laut digunakan untuk diubah ke dalam citra grayscale lalu dilakukan segmentasi pada corak tubuhnya. Daerah hasil segmentasi tersebut digunakan untuk mengetahui pola corak tubuh ikan menggunakan deteksi tepi Canny. Hasil nilai dimensi menggunakan box counting diklasifikasikan menggunakan metode K-Means Clustering dengan 8 klaster yang memiliki nilai akurasi sebesar 90%.

Kata Kunci: Corak Tubuh Ikan Laut, Box Counting, K-Means.
Peramalan PDRB PERAMALAN PDRB DI JAWA TIMUR MENGGUNAKAN MODEL ARIMAX DENGAN VARIABElL EKSOGEN EKSPOR-IMPOR
Authors: Salsabila Nada , Oktaviarina Affiati
Published: January 2024

PDRB (Pendapatan Domestik Regional Bruto) merupakan salah satu faktor yang mempengaruhi pertumbuhan ekonomi dimana pertumbuhan ekonomi merupakan tolak ukur kesejahteraan masyarakat. Faktor-faktor yang mempengaruhi PDRB adalah Ekspor-Impor. Ekspor-Impor berpengaruh secara positif dan signifikan terhadap PDRB. Salah satu provinsi di Indonesia yang mengalami peningkatan pada PDRB ialah Jawa Timur. Dengan adanya fenomena peningkatan tersebut penelitian ini akan menerapkan model ARIMAX pada peramalan PDRB di Jawa Timur dengan variabel eksogen Ekspor - Impor.model ARIMAX dapat mengkombinasikan beberapa data dan mengetahi hubungan antar variabel Yt dan variabel Xt. Model ARIMAX adalah sebuah modifikasi dari metode ARIMA dengan penambahan variabel prediktor. Penentuan model ARIMAX dalam penelitian ini, menggunakan oleh metode Maximum Likelihood Estimation dalam proses estimasi parameternya. Nilai AIC digunakan dalam pemilihan model terbaik dan Nilai MAPE untuk mengukur akurasi data ramalan. Model ARIMAX yang dapat digunakan untuk peramala PDRB di Jawa Timur adalah ARIMAX(0,2,1). Dimana model tersebut merupakan model terbaik karena sesuai dengan uji signifikansi dan diagnostik checking dengan nilai AIC adalah 892.62. Akurasi hasil peramalan pada data testing tergolong bagus karena memiliki nilai MAPE sebesar 1.76% atau 0.176. Hasil Peramalan pada periode selanjutnya yaitu pada tahun 2023 Kuartil III sampai 2025 Kuartil IV juga mengalami kenaikan secara perlahan.
GRAF YANG TERKAIT DENGAN UP-ALJABAR
Authors: Amalia Nurul , Lukito Agung
Published: January 2024

Dalam artikel ini dikenalkan konsep graf sederhana tak berarah yang berkaitan dengan UP-aljabar komutatif, disebut graf UP-aljabar, dengan himpunan titiknya merupakan himpunan elemen UP-aljabar komutatif. Juga dikenalkan graf kelas ekuivalensi dari UP-aljabar komutatif dan dibuktikan beberapa hasil terkait berdasarkan sifat graf UP-aljabar. Di samping itu, ditunjukkan bahwa jika graf UP-aljabar adalah bipatrit lengkap, maka graf kelas ekuivalensi dari UP-aljabar merupakan sebuah sisi. Demikian pula, akan disajikan satu algoritma untuk memeriksa apakah suatu himpunan dengan operasi biner tertentu merupakan UP-aljabar atau bukan.

Kata Kunci: UP-aljabar, UP-ideal, ideal annihilator, graf kelas ekuivalensi.
Identifikasi Gangguan Degradation Fault pada Photovoltaic Array berbasis Artificial Neural Network
Authors: SUHARININGSIH SUHARININGSIH , SUNARNO EPYK , SALSABILA MUTIARA NADHIFAH , ANGGRIAWAN DIMAS OKKY , PRASETYONO EKA
Published: January 2024

ABSTRAKEnergi terbarukan sudah mulai mendominasi dunia sejak puluhan tahun lalu, terutama listrik tenaga surya. Pada setiap instalasi PV terdapat gangguan yang sering terjadi, salah satunya adalah degradation fault. degradation fault merupakan jenis gangguan berupa perubahan warna pada lapisan Ethylene Vinyl Acetate dari yang berwarna putih menjadi kuning hingga kecoklatan. Perubahan warna tersebut disebabkan oleh usia pemakaian dan suhu yang terlalu panas dan dapat menyebabkan penurunan arus yang sangat drastis. Kejadian ini mengakibatkan penurunan Isc mencapai 13%. Hal ini tidak baik jika terus dibiarkan pada instalasi solar panel. Oleh karena itu, pada jurnal ini akan membahas pengidentifikasian degradation fault pada array PV dengan Artificial Neural Network. ANN akan mengidentifikasi adanya penurunan arus pada PV array. Dari hasil yang didapatkan bahwa penurunan arus mencapai 12% dan dapat mengidentifkasi adanya degradation fault.Kata kunci: degradation fault, discoloration, Ethylene Vinyl Acetate , short circuit current, artificial neural network ABSTRACTRenewable energy has started to dominate the world since decades ago, especially solar electricity. In every PV installation there are disturbances that often occur, one of which is a degradation fault. Degradation fault is a type of disturbance in the form of discoloration of the Ethylene Vinyl Acetate layer from white to yellow to brownish. The discoloration is caused by age of use and temperatures that are too hot and can cause a very drastic decrease in current. This incident resulted in a decrease in Isc reaching 13%. This is not good if it continues to be left on solar panel installations. Therefore, this journal will discuss the identification of degradation faults in PV arrays with Artificial Neural Networks. ANN will identify a decrease in current in the PV array. From the results obtained that the decrease in current reaches 12% and can identify a degradation fault.Keywords: degradation fault, discoloration, Ethylene Vinyl Acetate , short circuit current, artificial neural network
Biotoxicity of NH4+ on Nostoc Sphaeroides (diazotrophic cyanobacteria) in paddy floodwater
Authors:   College of Environment and Ecology, Hunan Agricultural University, Changsha, 410128, China, Shao Jihai , Fan Li ,   College of Environment and Ecology, Hunan Agricultural University, Changsha, 410128, China, Feng Ye ,   College of Environment and Ecology, Hunan Agricultural University, Changsha, 410128, China
Published: January 2024

In order to elucidate the toxicity of NH4+ on Nostoc Sphaeroides (commonly named GE-XIAN-MI in China, GXM), a diazotrophic cyanobacterium in paddy fields, this study investigated the growth, photosynthesis, N2-fixation, and oxidative-antioxidative characteristics of GXM under NH4+ stress in paddy floodwater. The results showed that the photosynthesis and the N2-fixing ability of GXM were inhibited by NH4+ at a concentration of 13.46 mg L-1 in paddy floodwater. The main target of NH4+ on photosystem II (PS II) of GXM was the electron donor side of react center. Oxygen evolution complex (OEC) was the secondary target of toxicity of NH4+ on PS II. The damage of PS II led to accumulation of ROS and resulted in oxidative damage on plasma membrane of GXM. Feedback inhibition and decrease of photosynthetic energy production may be the reasons for the decrease of N2-fixing ability of GXM under NH4+ stress. The results presented in this study suggest that high level of NH4+ loading may be a reason for the recession of GXM resource in paddy fields.
A Photo Essay Study on Matter~Meaning of Play Materials in the Field of Early Childhood Education
Authors:   Korean Society for Young Children Becoming Curriculum, Ryu Ye-Ram , Jung Hye-Young
Published: January 2024

This study aimed to explore the matter~meaning of play materials that exist in in the field of early childhood education. Through photo essay exploration, we attempted to reveal the agential cut of the teacher pressing the ‘shutter’ of the camera, alongside the material agency of the photo itself. Data were collected from photo essays, researcher journals, documents, and other materials from the 4-year-old N class at Public M Kindergarten in City B. Data were analyzed through the process of selecting photos, contextualizing, and categorizing. As a result of the study, the matter~meaning of play materials in the early childhood education field was found to include ‘play materials that traverse familiarity and unfamiliarity, play materials that are constantly created and lead to change, and play materials that are intertwined in the field of learning.’ Through this study, teachers need to perceive play materials as living and created materials, facilitate encounters with various play materials, and understand the learning that occurs in the entanglement with play materials, thereby leading to the implementation of the curriculum. Furthermore, it is expected that the actions of early childhood teachers who think and reflect with play materials in entangled relationships can open up new possibilities of teacher pedagogy oriented toward practice.
PENGARUH PEMAKAIAN AGREGAT HALUS (MUNTILAN, KALI BODRI, SINGOROJO) TERHADAP KUAT TEKAN BETON PADA VARIASI GEOMETRI SILINDER
Authors: Abidin Ali Nur , Panolas Yoga Bagus , Budirahardjo Slamet , Kristiawan Agung
Published: January 2024

Penggunaan beton semakin meningkat seiring dengan perkembangan zaman. Penggunaan beton sebagai salah satu pilihan disebabkan karena beton memiliki sifat kuat tekan yang tinggi. Core drill adalah suatu metode pengambilan sampel beton pada suatu struktur bangunan. Sampel yang diambil (bentuk silinder) selanjutnya dibawa ke laboratorium untuk dilakukan pengujian seperti kuat tekan. Penelitian ini bertujuan untuk menganalisis kuat tekan beton dengan perbandingan 1PC:2PS:3KR pada ukuran silinder 15 x 30 cm, dan perbandingan 1PC:2PS:3KR pada ukuran silinder 10 x 15 cm, 10 x 18 cm, 10 x 20 cm, dengan agregat halus (muntilan, kali bodri, dan singorojo). Penelitian ini menggunakan pendekatan kuantitatif dengan eksperimen. Sampel penelitian ini menggunakan beton keras dengan mengganti agregat halus pasir muntilan, kali bodri, dan singorojo. Pengujian menunjukan nilai kuat tekan beton dengan perbandingan 1PC:2PS:3KR dengan ukuran silinder 15 x 30cm dengan agregat halus umur 14 hari nilai kuat tekan beton (muntilan : 10,19 Mpa, kali bodri ; 8,90 Mpa, singorojo : 8,90 Mpa) dan umur 21 hari (muntilan : 11,22 Mpa, kali bodri : 9,73 Mpa, singorojo : 9,34 Mpa). Pengujian menggunakan cetakan variasi geometri silinder (10 x 20cm, 10 x 18cm, 10 x 15cm) mempengaruhi nilai kuat beton dan pemakaian agregat halus yang berbeda (pasir muntilan, kali bodri, dan singorojo) juga mempengaruhi nilai kuat tekan beton. Dari hasil perbandigan 1PC:2PS:3KR penggunaan pasir muntilan lebih disarankan untuk material kontruksi beton karena nilai kuat tekan beton pasir muntilan lebih tinggi.Kata Kunci: Pasir Muntilan, Kali Bodri, Singorojo, Kuat Tekan
ANALISIS KAPASITAS RUANG PARKIR MOBIL KAWASAN TAMAN WISATA AIR PANAS GUCI KABUPATEN TEGAL
Authors: Nafilarizqi Angie Belvavarian , Rizani Mohammad Debby , Yudaningrum Farida
Published: January 2024

Penelitian ini dilatar belakangi oleh adanya kekurangan lahan parkir disalah satu tempat wisata yaitu Taman wisata air panas guci, kabupaten Tegal yang tepatnya ada di tempat ruang parkir mobil B desa Bojong,bumijawa, kabupaten Tegal. Pada tempat ruang parkir mobil B sudah dilakukannya perubahan pengaturan manajemen perpakiran dengan menambah kantong – kantong parkir yang telah disediakan namun belum maksimal.Penelitian ini bertujuan mengetahui hasil survei lapangan sebagai berikut akumulasi parkir, durasi parkir, volume parkir, pergantian parkir, indeks parkir, kapasitas statis, dan serta kapasitas dinamis di tempat ruang parkir mobil B pada Taman Wisata Air Panas Guci kabupaten Tegal. Jenis penelitian ini adalah kuantitatif yang bertujuan untuk menunjukkan adanya pengaruh dalam perhitungan yang dilakukan dengan cara umum ke khusus dengan pengumpulan data baik secara data primer maupun data sekunder. Data primer dengan cara pengamatan secara langsung di lapangan dengan metode observasi dan dokumentasi di Taman Wisata Air Panas Guci kabupaten Tegal, sedangkan data sekunder yaitu data penujang seperti kabupaten Tegal, peta lokasi, dan jumlah penduduk kabupaten Tegal 2021. Teknik pengambilan data primer dengan cara mengambil perhitungan jumlah akumulasi parkir, durasi parkir, volume parkir, pergantian parkir, indeks parkir, kapasitas statis, dan serta kapasitas dinamis di tempat ruang parkir mobil B pada Taman Wisata Air Panas Guci kabupaten Tegal. Berdasarkan penelitian didapatkan akumulasi parkir sebesar 51 mobil, durasi parkir sebesar 59 mobil, volume parkir sebesar 129 mobil, pergantian parkir sebanyak 1 – 2 kali, indeks parkir sebanyak 72,9 %, kapasitas statis sebesar 70 SRP dan serta kapasitas dinamis sebesar 350 mobil.Kata Kunci: ruang parkir, karakteristik parkir, kapasitas parkir
The Phenomenon of Self-Education: Review of World Research Contexts
Authors:   Southern Federal University, Taganrog, Russia, Lyz Natalia , Lyz Alexander ,   Southern Federal University, Taganrog, Russia
Published: January 2024

Modern education overcomes institutional, age, and spatial limits. It provides each person with the opportunity to lifelong learning, and it also allows managing the learning process. Self-education as a proactive human activity for the purposeful accumulation of experience is becoming a relevant subject of scientific research. The research contexts of self-education in world science are the following concepts: «adult learning», «continuous learning», «continuous professional development», «informal learning», «lifelong learning», «non-formal learning», «self-development», «self-directed learning», «self-education», «workplace learning». A review of the segments of the subject field formed by these concepts was carried out. The main goal was to compare and determine the possibilities of using these concepts for the study of self-education in educational, organizational (professional) and life contexts. The articles indexed in the Scopus database served as the basis for the review. Quantitative indicators characterizing the prevalence of terms and the content of the sought-for concepts in the most cited articles were identified. The results showed that the significant amount of knowledge about self-education is concentrated in the segments related to the concepts of lifelong learning, self- directed learning, informal learning, and workplace learning. The most promising is the study of self-education of students or professionals based on the theories of self-directed and informal learning. The theories of self-directed learning are necessary to consider the initiation, implementation, and control of person’s proactive learning activities. The theories of informal learning are necessary to analyze the spontaneous, but meaningful experience accumulation in the process of various activities. The materials of the review, which describe contexts for the study of self-education, will be useful for scientists to determine the current research perspectives and select an adequate theoretical framework.
Consideration of Temperature Factors when Designing Butterfly Check Valves for Hazardous Production Facilities
Authors: Soboleva Julia , Kerimov Abdulmejid , Lampezhev Abas
Published: January 2024

The safety of hazardous production facilities is directly related to the reliability of pipeline systems, which must be ensured regardless of environmental conditions. Accidents on pipeline sections can have catastrophic consequences associated with damage to human health and the environment. Damage to the metal of pipeline elements during operation due to internal corrosion occurring under the influence of the working fluid is one of the main reasons for failure. This study aims to develop an improved butterfly check valve (BCV), which is a pipeline element. For this purpose, various structural materials used in the production of check valves were analyzed, and the changes in their mechanical properties under the influence of temperature were also considered. Based on this material, a butterfly check valve was developed. The stress-strain state of the developed structure was assessed using the finite element method (FEM). Strains, stresses, and displacements were calculated to evaluate valve performance. These calculations are necessary to determine the most loaded elements of the BCV at the maximum and minimum ambient temperatures. The following conclusions were obtained: X6CrNiTi18-10 stainless steel grade is the most suitable material for piping systems transporting liquids in production facilities. On the basis of the simulation results, the values of equivalent stresses, maximum strains, and displacements were obtained. The research results confirmed the performance of the improved design, the unhindered motion of the working fluid in the working direction, and the convenient connection to horizontal and vertical sections of the pipeline. Doi: 10.28991/CEJ-SP2023-09-020 Full Text: PDF
DIGITAL CRIMINAL CASE. PROSPECTS AND ISSUES
Authors:   Russian State University for the Humanities, Mityushin Dmitrii A. , Molyakov Andrei S. ,   Russian State University for the Humanities
Published: January 2024

In a sense digitalization penetrates into all spheres of life of modern society. It is due both to the entry of a large number of states into the postindustrial era of development, and to the introduction of separate legislative acts for the digitalization of various spheres of society. The issues of digitalization have not left aside such areas as criminal process and criminal proceedings. There are heated discussions on the issue, both at various thematic conferences and in scientific publications by specialists of various scientific fields, mostly lawyers. Without going too much into legal subtleties, the article discusses the transformation of the “traditional” (paper) procedure of the criminal case formation into a digital form at the stages of its life cycle, starting from the initiation of a criminal case to its archiving. The prospects for such a transformation and issues that arise therefrom that need to be solved are shown. First of all, the technical issues in such digitalization of criminal proceedings are considered. The information presented in the article will be useful not only for specialists in the field of information technology and information protection, but also for those in the field of criminal law and criminal procedure