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"A mechanical assembly consists of several components to perform an intended function. At the design stage, the intended function must be converted into critical product dimensions. After determining the dimensions, a designer must determine the assembly tolerance and allocate this tolerance to the tolerances of the corresponding components. After determining the optimal tolerances, process selection must be conducted along with production allocation to the selected process. There are three aspects in commercial competition that must be considered by a manufacturing company: cost, quality, and delivery. The aim of this research is to develop an optimization model for process selection for a make to order company to minimize manufacturing cost, quality loss, and lateness cost. The model attempts to determine optimal tolerance and production allocation, which takes into consideration the production capacity and process sequence. Hence, the model attempts to include not only the product design decision, but also to solve the process selection and allocation problems. A numerical example is provided to show the implementation of the model."

"A mechanical assembly consists of several components to perform an intended function. At the design stage, the intended function must be converted into critical product dimensions. After determining the dimensions, a designer must determine the assembly tolerance and allocate this tolerance to the tolerances of the corresponding components. After determining the optimal tolerances, process selection must be conducted along with production allocation to the selected process. There are three aspects in commercial competition that must be considered by a manufacturing company: cost, quality, and delivery. The aim of this research is to develop an optimization model for process selection for a make to order company to minimize manufacturing cost, quality loss, and lateness cost. The model attempts to determine optimal tolerance and production allocation, which takes into consideration the production capacity and process sequence. Hence, the model attempts to include not only the product design decision, but also to solve the process selection and allocation problems. A numerical example is provided to show the implementation of the model."

"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"

"In this paper, two highlysensitive photonic crystal fiber (PCF) structures with microstructure core and claddinghave been demonstrated for Ethanol sensing. Themicrostructure core of both proposedPCFs is designed with supplementary holes in an octagonal formation. We have investigated therelative sensitivity and the confinement loss of the proposed PCF structuresemploying a fullvectorial finite element method (FEM). The proposed PCFs work at a widetransmission band covering 0.8 µm to 2 µm and exhibit high sensitivity and lowconfinement loss simultaneously. The numerical analysis shows that the circular shape of air holes in the first ring is a moresalient attribute forincreasing sensitivity and the presence of the square shape of air holes in the first ring showsbetter performance to reduce confinement loss."

"Commercialization ofbioethanol has recently intensified due to its market stability, low cost,sustainability, alternative fuel energy composition, greener output andcolossal fossil fuel depletion. Recently, because of greenhouse intensityworldwide, many researches are ongoing to reprocess the waste as well asturning down the environmental pollution. With this scenario, the invention ofbioethanol was hailed as a great accomplishment to transform waste biomass tofuel energy and in turn reduce the massive usages of fossil fuels. In thisstudy, our review enlightens various sources of plant-based waste feed stocksas the raw materials for bioethanol production because they do not adverselyimpact the human food chain. However, the cheapest and conventionalfermentation method, yeast fermentation is also emphasized here notably forwaste biomass-to-bioethanol conversion. Since the key fermenting agent, yeastis readily available in local and international markets, it is morecost-effective in comparison with other fermentation agents. Furthermore, yeasthas genuine natural fermentation capability biologically and it produces zerochemical waste. This review also concerns a detailed overview of the biologicalconversion processes of lignocellulosic waste biomass-to-bioethanol, thediverse performance of different types of yeasts and yeast strains,plusbioreactor design, growth kinetics of yeast fermentation, environmentalissues, integrated usages on modern engines and motor vehicles, as well asfuture process development planning with some novel co-products."

"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."

"Rice husk is one of themost abundant biomass wastes in Indonesia. One way to convert it into analternative source of energy is biomass gasification. This is a thermochemicalprocess which converts biomass feedstock into fuel gas or chemical feedstockgas (producer gas). The gasification type which is developed in this study isfixed bed downdraft type due to its low tar content and compatibility inmicroscale implementation. One major problem with the implemented biomassgasification reactor was ruggedness of the partial oxidation process due to theabsence of air in the reactor?s middle section, which consequently affected thepyrolysis zone. Several experiments were conducted previously using coconutshells and rice husks as solid feedstock, where an equivalence ratio (ER) of0.4 was obtained. Therefore, in order to optimize the pyrolysis zone, themodification conducted involves adding a circular air intake into the gasifier.Experiments were conducted in a pyrolysis temperature range of 300?700oCwith ER variation of 0.19, 0.24, 0.27 and 0.31. The results show that a goodquality producer gas is produced at an ER value of 0.24. This value shows apromising result because the ER value of biomass gasification standard is 0.25."

"As an initial analysis,numerical simulation has more advantages in saving time and costs regarding experiments. For example, variations in flowconditions and geometry can be adjusted easily to obtain results. Computationalfluid dynamics (CFD) methods, suchas the k-ε model, renormalizationgroup (RNG) k-ε model and reynolds stress model (RSM), are widely used toconduct research on differentobjects and conditions. Choosing the appropriate model helps produce and developconstant values.Modeling studies as appropriate, i.e., in the turbulent flow simulation in the windtunnel, isdone to get a more accurate result. This study was conducted by comparing the results ofthe simulation k-ε model, RNG k-ε model and RSM, which is validated by the testresults. The air had adensity of 1,205 kg/m3, a viscosity of 4×10-5 m2/sand a normal speed of 6 m/s. By comparing the simulation results of the k-ε model, RNG k-ε model and RSM, which isvalidated by the test results, the third turbulencemodel provided good results to predict the distribution of speedand pressure of the fluid flow in the wind tunnel. As for predicting theturbulent kinetic energy, turbulent dissipation rate and turbulent effectiveviscosity, the k-εmodel was effectivelyused with comparable results to the RSM models."

"Telecommunication technology is very fast developing.One of them is mobile phone technology.The question is how to detect mobile phone position when it is used,especially in emergency....."

"An active Radio-Frequency Identification (RFID) tag is a low-power device, which is often used as a tracking device, where operation of this tag will be in remote areas from an electrical power source. Therefore, this device requires an independent power source. To meet these needs, solar power may be used, which can be accessed anywhere there is sunlight. Supercapacitors (SC) are used as an energy source to support a solar power system. The advantage of supercapacitors, as an energy storage device, is their long life cycle that means more charging and discharging processes compared to a conventional battery. The design and fabrication of a solar power system for an active RFID tag with supercapacitors as the energy storage will be covered in this paper."