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"A multi modelpredictive control and proportional-integral controller switching (MMPCPIS)approach is proposed to control a nonlinear distillation column. The study wasimplemented on a multivariable nonlinear distillation column (Column A). Thesetpoint tracking and disturbance rejection performances of the proposedMMPCPIS were evaluated and compared to a proportional-integral(PI) controller and the hybrid controller (HC). MMPCPIS developed to overcome theHC?s limitation when dealing with very large disturbance changes (50%). MMPCPIS provided improvements by 27% and 31%of the ISE (integral of square error) for feed flow rate andfeed composition disturbance changes, respectively, comparedwith the PI controller, and 24% and 54% of the ISE for feed flow rate and feedcomposition disturbancechange, respectively, compared with HC."

"A multi model predictive control and proportional-integral controller switching (MMPCPIS) approach is proposed to control a nonlinear distillation column. The study was implemented on a multivariable nonlinear distillation column (Column A). The setpoint tracking and disturbance rejection performances of the proposed MMPCPIS were evaluated and compared to a proportional-integral (PI) controller and the hybrid controller (HC). MMPCPIS developed to overcome the HC’s limitation when dealing with very large disturbance changes (50%). MMPCPIS provided improvements by 27% and 31% of the ISE (integral of square error) for feed flow rate and feed composition disturbance changes, respectively, compared with the PI controller, and 24% and 54% of the ISE for feed flow rate and feed composition disturbance change, respectively, compared with HC."

"East Java Province inIndonesia is the centre of the eastern Indonesia region and it has a fairlyhigh economic significance, which has contributed 14.85% to the national GrossDomestic Product (GDP). The role of Large and Medium Scale ManufacturingIndustry (LMSMI) clusters in this province is very important and strategic asone of the main drivers for economic progress and it becomes a part of theefforts to improve the society's life. Therefore, it is necessary to evaluatethe performance of LMSMI clusters continuously. The purpose of this study is toinvestigate the productivity changes of LMSMI clusters in East Java Province,Indonesia, so that they will be able to survive, grow and compete in facingglobal competition. The method used in this study is the method of DEA-basedMalmquist Productivity Index. The result of this study indicates that 50% ofthe LMSMI clusters in East Java Province are in the category of improvedproductivity, while the remaining clusters are in the category of decliningproductivity."

"The relative significance ofthe parallel middle body and stern form in the wake formation of single-screwlarge ships and their contribution to the ship?s viscous resistance are studied by using computational fluid dynamics (CFD). A10450-DWT tanker is considered by varying the ratio of theparallel-middle-body?s length to the ship?s length (Lmb/L) and by varying the shape of the stern form from aV-like to a U-like underwater stern transom section. In all the calculations,the principal dimension and the displacement of the ships are kept constant. Alarger value for the parallel-middle-body relative length (Lmb/L) of ships with the same stern form results in alarger drag coefficient but does not affect the nominal wake fractionsignificantly. A change in the shape of the underwater stern form,from a V-like to a U-like section, results in a much larger drag coefficientascribed to the much larger wake fraction. The stern form dominantly affectsthe nominal wake fraction and the ship?s viscous resistance compared to theparallel-middle-body relative length."

"Operational Technology (OT) adalah salah satu komponen yang menjadi lingkup teknologi yang sangat berkembang saat ini, yang dalam sistemnya dapat menghubungkan antarperangkat fisik melalui jaringan internet atau intranet. Saat ini PT XYZ menerapkan sistem OT untuk mendukung dan meningkatkan kapasitas produksi dan mulai ada kebutuhan untuk dibuat menjadi sistem yang dapat diintegrasikan dengan jaringan IT dan internet. Berdasarkan hasil observasi ditemukan bahwa dalam penerapan sistem OT di perusahaan masih memiliki kekurangan kontrol keamanan yang menyebabkan sistem tersebut tidak memenuhi kepatuhan terhadap kebijakan keamanan yang dimiliki perusahaan dan berpotensi menjadi celah keamanan yang dapat mengancam sistem perusahaan dan memberi kerugian yang besar pada perusahaan secara finansial. Penelitian ini dilakukan dengan mengidentifikasi aset dan risiko untuk kemudian diberikan kontrol keamanan yang sesuai dengan kondisi implementasi sistem dalam perusahaan dan dijadikan standar untuk mengamankan sistem integrasi IT-OT yang diimplementasikan di dalam perusahaan. Kontrol keamanan yang digunakan mengacu pada standar global IEC 62443 tentang keamanan Industrial Control System (ICS). Dari hasil pemetaan dengan acuan standar IEC62443 didapatkan rancangan kontrol tambahan yang diimplementasikan ke komputer yang terhubung dengan mesin sebagai mitigasi untuk risiko-risiko yang memiliki tingkat ekstrim dan tinggi. Selain kontrol secara teknis, dilakukan juga perancangan prosedur dan instruksi kerja sebagai kontrol tambahan.

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Operational Technology (OT) is one of the components that are within the scope of today's highly developed technology, which in its system can connect physical devices via the internet or intranet networks. Currently PT XYZ is implementing an OT system to support and increase production capacity and there is a need to make the system can be integrated with IT networks and the internet. Based on the results of observations, it was found that in the implementation of the OT system in the company still has a lack of security control which causes the system does not meet compliance with the company's security policies and has the potential to become a security gap that can be a threat to the company's system and give big losses to the company financially. This research was conducted by identifying assets and risks and then provide security control according to the conditions of system implementation in the company and used as a standard to secure the IT-OT integration system implemented within the company. The security controls use the global standard IEC 62443 on Industrial Control System (ICS) safety as a reference. From the results of the mapping with reference to the IEC62443 standard, additional control designs are obtained which are implemented to computers connected to machines as mitigation for risks that have extreme and high levels. In addition to technical control, procedures and work instructions are also designed as additional controls"

"Pelumas merupakan senyawa yang digunakan untuk mengurangi gaya gesek dan keausan antar komponen yang berkontak satu sama lain. Base oil merupakan komponen penting dalam pelumas sehingga pemilihan base oil dapat menentukan sifat dari pelumas tersebut. Kolom distilasi pada proses separasi base oil ester memiliki potensi bahaya yang cukup tinggi sehingga perlu adanya pengendalian pada unit tersebut. Pada penelitian ini, Multivariable Model Predictive Control (MMPC) digunakan sebagai pengendali tingkat lanjut untuk mengendalikan 4 pasangan manipulated variable (MV) dan controlled variable (CV) pada unit distilasi. Penyetelan pengendali dilakukan dengan pemodelan first order plus derivative time (FOPDT) dengan metode Smith, Wade, Lilja, dan Solver yang dilanjutkan dengan penentuan parameter MMPC. Penentuan parameter MMPC dengan metode fine-tuning menghasilkan prediction horizon (P) sebesar 375, control horizon (M) sebesar 245, dan sampling time (T) sebesar 1. Pengendalian dengan MMPC 4×4 hasil fine-tuning mampu mengurangi nilai Integrated Absolute Error (IAE) sebesar 3,31 – 80,40% dan nilai Integrated Squared Error (ISE) sebesar 2,77 – 81,33% dibandingkan hasil pengendalian PI pada pengujian set point tracking. Selain itu, pengendalian MMPC juga dapat mengurangi nilai IAE sebesar 3,17 – 77,48% dan nilai ISE sebesar 23,83 – 88,44% dibandingkan hasil pengendalian PI pada pengujian disturbance rejection.

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Lubricants are compounds used to reduce friction and wear between components in contact with each other. Base oil is an important component in lubricants so that the selection of base oil can determine the nature of the lubricant. The distillation column in the ester base oil separation process has a high potential hazard, so it is necessary to control the unit. In this study, Multivariable Model Predictive Control (MMPC) is used as an advanced controller to control 4 pairs of manipulated variables (MV) and controlled variables (CV) in the distillation unit. Controller tuning is done by first order plus derivative time (FOPDT) modeling with Smith, Wade, Lilja, and Solver methods followed by MMPC parameter determination. The determination of MMPC parameters with the fine-tuning method results in a prediction horizon (P) of 375, a control horizon (M) of 245, and a sampling time (T) of 1. Control with MMPC fine-tuning results can reduce the Integrated Absolute Error (IAE) value by 3.31 – 80,40% and the Integrated Squared Error (ISE) value by 2.77 – 81,33% compared to the PI control results in the set point tracking test. In addition, MMPC  control can also reduce the IAE value by 3.17 – 77,48% and the ISE value by 23.83 – 88,44% compared to the PI control results in the disturbance rejection test."

"Berkembangnya teknologi informasi dan komunikasi menjadi tantangan untuk menyediakan layanan tersebut di Indonesia. VSAT Ku-Band salah satu teknologi yang dapat digunakan di negara kepulauan seperti Indonesia. VSAT Ku-Band memiliki ukuran yang lebih kecil dan harga yang terjangkau dibandingkan VSAT C-Band dengan power penerima yang lebih kecil namun kapasitas kecepatan internetnya yang lebih besar. VSAT Ku-Band memiliki kelemahan dimana amat rentan terhadap gangguan cuaca khususnya hujan dan melemahnya sinyal satelit pada daerah batasan kerja satelit. Antena VSAT Ku-Band salah satu perangkat yang menentukan ketahanan dan kualitas sinyal yang didapatkan. Pada penelitian ini dilakukan perancangan antena horn sebagai pencatu parabola pada kanal Ku-Band untuk mendapatkan gain yang tinggi pada aplikasi VSAT Ku-Band. Pencatu horn dirancang menggunakan wire medium berbentuk persegi yang diletakkan di dalam antena dan penambahan bagian pada awal aperture horn untuk meningkatkan parameter gain antena. Pada penelitian ini dilakukan studi literatur untuk mempelajari teori pendukung, simulasi pada CST Microwave Studio, fabrikasi dan pengukuran untuk memvalidasi kinerja dari antena tersebut. Dari penelitian ini telah didapatkan desain antena VSAT Ku-Band untuk frekuensi kerja 10,7-14,5 GHz dengan polarisasi linear, VSWR pada frekuensi kerja penerima 1,5 dan VSWR pada frekuensi kerja pengirim max 1,3 kemudian gain pada frekuensi kerja penerima 38 dBi dan gain pada frekuensi kerja pengirim 42 dBi.

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The development of information and communication technology is a challenge to provide these services in Indonesia. VSAT Ku-Band is a technology that can be used in an archipelago such as Indonesia. VSAT Ku-Band has a smaller size and an affordable price compared to VSAT C-Band with smaller receiver power but greater internet speed capacity. VSAT Ku-Band has a weakness where it is very vulnerable to weather disturbances, especially rain and weakening of satellite signals in satellite boundaries. Ku-Band VSAT antenna is a device that determines the resistance and quality of the signal obtained. In this study the design of horn antennas as a satellite dish on the Ku-Band channel to get high gain in the Ku-Band VSAT application. Horn feeders are designed using a rectangular wire medium placed inside the antenna and the addition of parts at the beginning of the aperture horn to increase the antenna gain parameters. In this research, a literature study was conducted to study supporting theories, simulations on CST Microwave Studio, fabrication and measurements to validate the performance of the antenna. From this research, a Ku-Band VSAT antenna design has been obtained for a working frequency of 10.7-14.5 GHz with linear polarization, VSWR at the working frequency of the receiver is 1.5 and VSWR at the maximum working frequency of the sender is 1.3 then the gain is at the working frequency of the receiver 38 dBi and the gain at the sender's working frequency is 42 dBi."

"Computer simulation program has been developed on the basis of Liapunov approach for the study of MRAC technique applied to pressure control for a vacuum system. Both proportional and integral feedback as well as disturbance feedforward is considered in the closed-loop system. The simulation result obtained with a personal computer demonstrates that this MRAC technique is feasible and provides effective and satisfactory control despite its poor initial control policies and wide range of choice for the adaptive gains. For a series of step disturbance, MRAC resulted in continually improved control with very good agreement obtained between process and reference model responses after the second disturbance."

"Review pengendalian umum teknologi informasi dan pengendalian aplikasi adalah jenis jasa review yang mendukung audit laporan keuangan, dalam hal ini memberikan keyakinan kepada auditor ekternal bahwa perusahaan telah menerapkan pengendalian umum teknologi informasi dan pengendalian aplikasi dalam menyusun laporan keuangan. Metode yang digunakan dalam melakukan review adalah membandingkan kebijakan dan implementasi pengendalian PT. FGH dengan indikator RSM. Hasil dari review ini adalah pengidentifikasian kelemahan pengendalian umum teknologi informasi dan pengendalian aplikasi PT FGH serta rekomendasi untuk menanggulangi kelemahan tersebut.

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Information technology general controls and application controls review is the kind of service that support the audit of financial statements, in this case provide assurance to the external auditor that the company has inplemented information technology general control and application control in preparing the financial statements. The method used in conducting the review was by comparing policies and implementation of PT. FGH controls with RSM indicator. The results of this review is identification of PT. FGHs information technology general control and application control weaknesses as well as recommendations to address these weaknesses."