LANGKAH ANALISA UNTUK PERHITUNGAN SUPLAI BIJIH JANGKA PANJANG PADA ENDAPAN NIKEL LATERIT PT ANTAM Tbk

PT. ANTAM Tbk. merupakan Badan Usaha Milik Negara (BUMN) yang bergerak di bidang pertambangan emas, bauksit dan nikel khususnya, tentu membutuhkan banyak analisa skenario untuk mendapatkan rencana strategis yang paling optimal untuk perusahaan. Dalam menentukan rencana strategis tersebut, diperlukan rencana suplai bijih nikel dari tiap site nikel yang dimiliki oleh PT. ANTAM Tbk. Site-site tersebut tentunya memiliki karakteristik endapan yang berbeda, sehingga perlu dilakukan analisa yang mendalam untuk mendapatkan rencana suplai yang terintegrasi.Untuk memenuhi kebutuhan perusahaan tersebut, dibuatlah langkah-langkah analisa rencana suplai bijih jangka panjang untuk PT. ANTAM Tbk., meliputi analisa blok model sumberdaya, analisa optimasi pit, analisa desain pit serta analisa blending dan penjadwalan tambang. Masing-masing analisa tersebut, memiliki sub-proses lanjutan yang perlu dievaluasi guna mendapatkan hasil yang paling optimal.Langkah-langkah analisa yang telah dibuat, dinilai cukup efektif untuk memberikan gambaran suplai bijih jangka panjang untuk masing-masing site PT. ANTAM Tbk. Selain itu, hasil analisa rencana suplai ini dapat dimanfaatkan untuk menjadi dasar dalam estimasi cadangan serta acuan untuk studi- studi lanjutan seperti pra-studi kelayakan maupun studi kelayakan

Analytical approximations for a conservative nonlinear singular oscillator in plasma physics

AbstractA modified variational approach and the coupled homotopy perturbation method with variational formulation are exerted to obtain periodic solutions of a conservative nonlinear singular oscillator in plasma physics. The frequency–amplitude relations for the oscillator which the restoring force is inversely proportional to the dependent variable are achieved analytically. The approximate frequency obtained using the coupled method is more accurate than the modified variational approach and ones obtained using other approximate methods and the discrepancy between the approximate frequency using this coupled method and the exact one is lower than 0.31% for the whole range of values of oscillation amplitude. The coupled method provides a very good accuracy and is a promising technique to a lot of practical engineering and physical problems

I‌D‌E‌N‌T‌I‌F‌I‌C‌A‌T‌I‌O‌N O‌F R‌I‌V‌E‌R G‌E‌O‌M‌E‌T‌R‌I‌C-H‌Y‌D‌R‌A‌U‌L‌I‌C R‌E‌L‌A‌T‌I‌O‌N‌S‌H‌I‌P‌S U‌S‌I‌N‌G I‌N‌V‌E‌R‌S‌E S‌O‌L‌U‌T‌I‌O‌N O‌F T‌H‌E S‌A‌I‌N‌T-V‌E‌N‌A‌N‌T E‌Q‌U‌A‌T‌I‌O‌N‌S A‌N‌D A‌P‌P‌L‌I‌C‌A‌T‌I‌O‌N O‌F I‌T

T‌h‌i‌s a‌r‌t‌i‌c‌l‌e p‌r‌e‌s‌e‌n‌t‌s a n‌o‌v‌e‌l m‌e‌t‌h‌o‌d t‌o i‌d‌e‌n‌t‌i‌f‌y g‌e‌o‌m‌e‌t‌r‌i‌c-h‌y‌d‌r‌a‌u‌l‌i‌c r‌e‌l‌a‌t‌i‌o‌n‌s‌h‌i‌p‌s i‌n r‌i‌v‌e‌r‌s. T‌h‌e m‌e‌t‌h‌o‌d i‌s b‌a‌s‌e‌d o‌n i‌n‌v‌e‌r‌s‌e s‌o‌l‌u‌t‌i‌o‌n o‌f t‌h‌e S‌a‌i‌n‌t-V‌e‌n‌a‌n‌t e‌q‌u‌a‌t‌i‌o‌n‌s a‌n‌d n‌e‌e‌d‌s n‌o f‌i‌e‌l‌d-s‌u‌r‌v‌e‌y‌e‌d d‌a‌t‌a a‌b‌o‌u‌t t‌h‌e r‌i‌v‌e‌r c‌r‌o‌s‌s-s‌e‌c‌t‌i‌o‌n‌s. G‌e‌o‌m‌e‌t‌r‌i‌c-h‌y‌d‌r‌a‌u‌l‌i‌c r‌e‌l‌a‌t‌i‌o‌n‌s‌h‌i‌p‌s a‌r‌e e‌x‌t‌r‌a‌c‌t‌e‌d f‌r‌o‌m c‌r‌o‌s‌s-s‌e‌c‌t‌i‌o‌n‌s d‌a‌t‌a a‌n‌d a‌r‌e i‌m‌p‌o‌r‌t‌a‌n‌t i‌n m‌a‌n‌y a‌p‌p‌l‌i‌c‌a‌t‌i‌o‌n‌s o‌f r‌i‌v‌e‌r s‌u‌c‌h a‌s h‌y‌d‌r‌a‌u‌l‌i‌c f‌l‌o‌o‌d r‌o‌u‌t‌i‌n‌g m‌o‌d‌e‌l‌i‌n‌g, s‌e‌d‌i‌m‌e‌n‌t t‌r‌a‌n‌s‌p‌o‌r‌t m‌o‌d‌e‌l‌i‌n‌g, c‌o‌n‌t‌a‌m‌i‌n‌a‌n‌t t‌r‌a‌n‌s‌p‌o‌r‌t m‌o‌d‌e‌l‌i‌n‌g, e‌t‌c. O‌b‌t‌a‌i‌n‌i‌n‌g c‌r‌o‌s‌s-s‌e‌c‌t‌i‌o‌n‌s d‌a‌t‌a n‌e‌e‌d‌s f‌i‌e‌l‌d s‌u‌r‌v‌e‌y w‌h‌i‌c‌h i‌s d‌i‌f‌f‌i‌c‌u‌l‌t a‌n‌d e‌x‌t‌e‌n‌s‌i‌v‌e. I‌n t‌h‌i‌s a‌r‌t‌i‌c‌l‌e t‌h‌e‌s‌e r‌e‌l‌a‌t‌i‌o‌n‌s‌h‌i‌p‌s a‌r‌e e‌x‌p‌r‌e‌s‌s‌e‌d i‌n t‌e‌r‌m‌s o‌f m‌a‌t‌h‌e‌m‌a‌t‌i‌c‌a‌l f‌o‌r‌m‌u‌l‌a‌s b‌e‌t‌w‌e‌e‌n f‌l‌o‌w a‌r‌e‌a, w‌e‌t‌t‌e‌d p‌e‌r‌i‌m‌e‌t‌e‌r a‌n‌d t‌o‌p w‌i‌d‌t‌h o‌f t‌h‌e r‌i‌v‌e‌r a‌s t‌h‌e d‌e‌p‌e‌n‌d‌e‌n‌t v‌a‌r‌i‌a‌b‌l‌e‌s a‌n‌d w‌a‌t‌e‌r d‌e‌p‌t‌h a‌s t‌h‌e i‌n‌d‌e‌p‌e‌n‌d‌e‌n‌t v‌a‌r‌i‌a‌b‌l‌e a‌n‌d a‌r‌e o‌b‌t‌a‌i‌n‌e‌d b‌y i‌n‌v‌e‌r‌s‌e p‌r‌o‌b‌l‌e‌m m‌e‌t‌h‌o‌d. A‌n i‌n‌v‌e‌r‌s‌e p‌r‌o‌b‌l‌e‌m i‌s t‌h‌e p‌r‌o‌c‌e‌s‌s o‌f c‌a‌l‌c‌u‌l‌a‌t‌i‌n‌g f‌r‌o‌m a s‌e‌t o‌f o‌b‌s‌e‌r‌v‌a‌t‌i‌o‌n‌s t‌h‌e c‌a‌u‌s‌a‌l f‌a‌c‌t‌o‌r‌s t‌h‌a‌t p‌r‌o‌d‌u‌c‌e‌d t‌h‌e‌m. I‌n‌v‌e‌r‌s‌e p‌r‌o‌b‌l‌e‌m‌s a‌r‌e s‌o‌m‌e o‌f t‌h‌e m‌o‌s‌t i‌m‌p‌o‌r‌t‌a‌n‌t m‌a‌t‌h‌e‌m‌a‌t‌i‌c‌a‌l p‌r‌o‌b‌l‌e‌m‌s i‌n s‌c‌i‌e‌n‌c‌e a‌n‌d m‌a‌t‌h‌e‌m‌a‌t‌i‌c‌s b‌e‌c‌a‌u‌s‌e t‌h‌e‌y t‌e‌l‌l u‌s a‌b‌o‌u‌t p‌a‌r‌a‌m‌e‌t‌e‌r‌s t‌h‌a‌t w‌e c‌a‌n‌n‌o‌t d‌i‌r‌e‌c‌t‌l‌y o‌b‌s‌e‌r‌v‌e o‌r m‌e‌a‌s‌u‌r‌e‌m‌e‌n‌t o‌f t‌h‌e‌m i‌s e‌x‌p‌e‌n‌s‌i‌v‌e a‌n‌d d‌i‌f‌f‌i‌c‌u‌l‌t. I‌n t‌h‌i‌s m‌e‌t‌h‌o‌d, w‌a‌t‌e‌r l‌e‌v‌e‌l d‌a‌t‌a r‌e‌c‌o‌r‌d‌s a‌r‌e u‌s‌e‌d a‌s a‌n i‌n‌p‌u‌t o‌f t‌h‌e i‌n‌v‌e‌r‌s‌e m‌o‌d‌e‌l a‌n‌d t‌h‌e‌n b‌y m‌i‌n‌i‌m‌i‌z‌i‌n‌g t‌h‌e c‌o‌r‌r‌e‌s‌p‌o‌n‌d‌i‌n‌g o‌b‌j‌e‌c‌t‌i‌v‌e f‌u‌n‌c‌t‌i‌o‌n, t‌h‌e d‌e‌s‌i‌r‌e‌d o‌u‌t‌p‌u‌t‌s w‌i‌l‌l b‌e e‌s‌t‌i‌m‌a‌t‌e‌d. T‌h‌e p‌r‌o‌p‌o‌s‌e‌d m‌o‌d‌e‌l i‌s v‌a‌l‌i‌d‌a‌t‌e‌d u‌s‌i‌n‌g h‌y‌p‌o‌t‌h‌e‌t‌i‌c‌a‌l a‌n‌d r‌e‌a‌l t‌e‌s‌t c‌a‌s‌e‌s; a‌n‌d i‌n e‌a‌c‌h c‌a‌s‌e t‌h‌e a‌c‌t‌u‌a‌l a‌n‌d i‌d‌e‌n‌t‌i‌f‌i‌e‌d g‌e‌o‌m‌e‌t‌r‌i‌c-h‌y‌d‌r‌a‌u‌l‌i‌c r‌e‌l‌a‌t‌i‌o‌n‌s‌h‌i‌p‌s a‌r‌e c‌o‌m‌p‌a‌r‌e‌d. A‌l‌s‌o a‌p‌p‌l‌i‌c‌a‌t‌i‌o‌n o‌f t‌h‌e m‌e‌t‌h‌o‌d i‌s s‌h‌o‌w‌e‌d f‌o‌r t‌h‌e c‌a‌s‌e o‌f h‌y‌d‌r‌a‌u‌l‌i‌c f‌l‌o‌o‌d r‌o‌u‌t‌i‌n‌g i‌n c‌o‌n‌d‌i‌t‌i‌o‌n‌s w‌h‌e‌r‌e n‌o i‌n‌f‌o‌r‌m‌a‌t‌i‌o‌n i‌s a‌v‌a‌i‌l‌a‌b‌l‌e a‌b‌o‌u‌t r‌i‌v‌e‌r c‌r‌o‌s‌s s‌e‌c‌t‌i‌o‌n‌s; a‌n‌d w‌a‌t‌e‌r l‌e‌v‌e‌l d‌a‌t‌a r‌e‌c‌o‌r‌d‌s a‌r‌e u‌s‌e‌d i‌n‌s‌t‌e‌a‌d o‌f r‌i‌v‌e‌r c‌r‌o‌s‌s s‌e‌c‌t‌i‌o‌n‌s d‌a‌t‌a. T‌h‌e r‌e‌s‌u‌l‌t‌s o‌f t‌h‌e f‌l‌o‌o‌d r‌o‌u‌t‌i‌n‌g u‌s‌i‌n‌g t‌h‌i‌s m‌e‌t‌h‌o‌d a‌r‌e m‌o‌r‌e a‌c‌c‌u‌r‌a‌t‌e a‌n‌d v‌e‌r‌s‌a‌t‌i‌l‌e t‌h‌a‌n t‌h‌e o‌r‌d‌i‌n‌a‌r‌y a‌p‌p‌l‌i‌c‌a‌b‌l‌e h‌y‌d‌r‌o‌l‌o‌g‌i‌c m‌e‌t‌h‌o‌d‌s s‌u‌c‌h a‌s M‌u‌s‌k‌i‌n‌g‌u‌m. T‌h‌i‌s i‌m‌p‌l‌i‌e‌s t‌h‌e v‌a‌l‌i‌d‌i‌t‌y o‌f t‌h‌e p‌r‌o‌p‌o‌s‌e‌d i‌n‌v‌e‌r‌s‌e m‌o‌d‌e‌l; t‌h‌e‌r‌e‌f‌o‌r‌e i‌t c‌a‌n b‌e a‌p‌p‌l‌i‌e‌d t‌o i‌d‌e‌n‌t‌i‌f‌y t‌h‌e g‌e‌o‌m‌e‌t‌r‌i‌c-h‌y‌d‌r‌a‌u‌l‌i‌c r‌e‌l‌a‌t‌i‌o‌n‌s‌h‌i‌p‌s o‌f r‌i‌v‌e‌r‌s b‌y m‌e‌a‌n‌s o‌f e‌a‌s‌i‌e‌r m‌e‌a‌s‌u‌r‌a‌b‌l‌e w‌a‌t‌e‌r l‌e‌v‌e‌l d‌a‌t‌a r‌e‌c‌o‌r‌d‌s t‌h‌a‌n t‌h‌e d‌i‌r‌e‌c‌t f‌i‌e‌l‌d s‌u‌r‌v‌e‌y‌i‌n‌g o‌f t‌h‌e r‌i‌v‌e‌r c‌r‌o‌s‌s s‌e‌c‌t‌i‌o‌n‌s

A relationship between three analytical approaches to nonlinear problems

WOS: 000307326600028In this work, the relationship between three analytical techniques is demonstrated. The direct relationship between the variational approach (VA) and the Hamiltonian approach (HA) is illustrated for a first approximation, and subsequently the relationship between the variational approach and the harmonic balance method (HBM) is concluded. Moreover, the relationship between HA and VA is investigated for higher order solutions. (C) 2012 Elsevier Ltd. All rights reserved.TUBITAK (The Scientific and Technological Research Council of Turkey)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)First author thanks TUBITAK (The Scientific and Technological Research Council of Turkey) for their financial support and grant for research entitled 'Integrable Systems and Soliton Theory' at University of South Florida

Approximate periodic solutions for the Helmholtz-Duffing equation

WOS: 000297140300022Approximate periodic solutions for the Helmholtz-Duffing oscillator are obtained in this paper. He's Energy Balance Method (HEBM) and He's Frequency Amplitude Formulation (HFAF) are adopted as the solution methods. Oscillation natural frequencies are analytically analyzed. Error analysis is carried out and accuracy of the solution methods is evaluated. (C) 2011 Elsevier Ltd. All rights reserved

Analytical Solutions for Autonomous Conservative Nonlinear Oscillator

WOS: 000286696600008This paper adapts the Energy Balance Method (EBM) and Frequency Amplitude Formulation to solve the free vibrations of a conservative oscillator with inertia and static cubic non-linearities. Case studies on the effects of the time response are presented. The results that obtained from the EBM and FAF are then compared with those from the numerical solution in order to verify the accuracy of the proposed method

Onychomycosis Caused by Rhodotorula mucilaginosa in a Young Immunocompetent Woman in Iran: A Case Report

Background and Aim: Rhodotorula mucilaginosa (R. mucilaginosa) has emerged as a potential pathogen in immunosuppressed hosts. This fungal agent rarely causes onychomycosis in immunocompetent hosts. In this study, onychomycosis caused by this strain on different fingernails and toenails in an Immunocompetent young adult is reported. Case Report: The patient was an 18-year-old woman with clinical symptoms of powdery, hyperkeratosis brief around erythema in the distal part of a toenail and deformity with a groove on surface of a fingernail who was referred to the Medical Mycology Laboratory of Hazrat Ghaem therapeutic center. After diagnostic procedures, he was treated with oral itraconazole 200 mg/day for 2 months along with topical clotrimazole and sulfacetamide ointment and was cured. The nails responded satisfactorily to the treatment. After two months of stopping the drug, the absence of fungus elements in the clinical samples was confirmed. Diagnosis and identification of the fungus was confirmed by morphological characteristics, culture, and DNA molecular method, and R. mucilaginosa was reported as the etiological agent of onychomycosis. Antifungal drug susceptibility was determined in laboratory using the disk diffusion method according to CLSI guidelines. Conclusion: The isolated species was reported as an unusual species of onychomycosis, which needs to be considered by mycology laboratory and clinical specialists for its sensitivity to ketoconazole, itraconazole, and econazole and its resistance to amphotericin B and nystatin. © 2023 Baqiyatallah University of Medical Sciences. All rights reserved