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"This book describes an effective framework for setting the right process parameters and new mold design to reduce the current plastic defects in injection molding. It presents a new approach for the optimization of injection molding process via (i) a new mold runner design which leads to 20 percent reduction in scrap rate, 2.5 percent reduction in manufacturing time, and easier ejection of injected part, (ii) a new mold gate design which leads to less plastic defects; and (iii) the introduction of a number of promising alternatives with high moldability indices. Besides presenting important developments of relevance academic research, the book also includes useful information for people working in the injection molding industry, especially in the green manufacturing field."

"This book describes an effective framework for setting the right process parameters and new mold design to reduce the current plastic defects in injection molding. It presents a new approach for the optimization of injection molding process via (i) a new mold runner design which leads to 20 percent reduction in scrap rate, 2.5 percent reduction in manufacturing time, and easier ejection of injected part, (ii) a new mold gate design which leads to less plastic defects; and (iii) the introduction of a number of promising alternatives with high moldability indices. Besides presenting important developments of relevance academic research, the book also includes useful information for people working in the injection molding industry, especially in the green manufacturing field."

"This book presents innovative ideas and technical contributions in the area of metasurfaces and antenna technologies. On the one hand, it presents an effective method to analyze metasurfaces constituted by metallic texture with certain geometries. It shows how this method can be applied to the design of metasurface (MTS) antennas for deep space communications and other planar microwave devices. On the other hand, the book reports on a general methodology developed for analyzing flat devices realized by using modulated MTSs, which opens new design possibilities for a large number of microwave devices based on the manipulation of SWs. Finally, a novel approach of reconfigurability, which is based on a class of checkerboard MTS, is explored. All in all, this book covers important insights and significant results on the emerging topic of metasurfaces, from theoretical and computational aspects to experiments."

"This thesis demonstrates a technology that enables pipetting-free high-throughput screening (HTS) on a miniaturized platform, eliminating the need for thousands of one-by-one pipetting and conventional liquid handling systems. This platform enhances accessibility to HTS and enables HTS to be used in small-to-medium scale laboratories. In addition, it allows large-scale combinatorial screening with a small number of valuable cells, such as patients primary cancer cells. This technique will have a high impact for widespread use of HTS in the era of personalized medicine.In this thesis, the author firstly describes the need and concept of partipetting for pipetting-free HTS platform. It is realized by the one-step pipetting and self-assembly of encoded drug-laden microparticles (DLPs) on the microwells. Next, the technical implementations required for the platform demonstration are described. It includes preparation of encoded DLPs, plastic chip fabrication, and realization of automated system. Lastly, screening of sequential drug combinations using this platform is demonstrated. This shows the potential of the proposed technology for various applications. "

"This book describes an original improvement in power quality of photovoltaic generation systems obtained by the use of a multilevel inverter implemented with level doubling network (LDN). Modulation principles and harmonic analysis of output voltages are proposed and introduced in detail for both single and three-phase LDN configurations. The analysis is then extended to dc-link current and voltage, with emphasis to low-frequency harmonics and switching frequency ripple. This work represents the first comprehensive implementation of maximum power point tracking (MPPT) schemes using the ripple correlation control (RCC) algorithm in the presence of multiple ripple harmonics, such as in the case of multi­level inverters. Numerical simulations and experimental tests are carefully reported here, together with practical insights into the design of dc-link capacitors."

"Paduan titanium Ti6Al4V merupakan material yang memiliki kombinasi sifat mekanik yang diperlukan untuk implan seperti keuletan yang baik, ketahanan korosi yang tinggi dan biokompatibilitas yang baik, sehingga banyak digunakan sebagai material untuk aplikasi implan biomedis. Salah satu metode yang saat ini banyak digunakan untuk memproduksi implant Ti6Al4V dengan menggunakan proses metal injection molding (MIM). Proses MIM banyak digunakan karena dapat memproduksi part dengan lebih efektif, dan biaya produksi yang lebih murah. Salah satu faktor penting dalam proses MIM adalah preparasi feedstock yang baik serta menentukan parameter proses yang optimum untuk mencegah terjadinya pembentukan lapisan oksida TiO2 pada hasil MIM karena akan mempengaruhi sifat mekanis paduan. Penelitian ini bertujuan untuk mengetahui pengaruh proses parameter pada setiap tahapan MIM terhadap hasil akhir produk injeksi. Feedstock Ti6Al4V diinjeksi pada suhu 200°C dan tekanan ±2100 psi kemudian dilakukan penghilangan binder dengan solvent debinding menggunakan n-heksana pada suhu 50°C selama 1, 2, dan 3 jam, dan dilanjut dengan thermal debinding pada 2 variasi atmosfer berbeda yaitu vakum dan argon dengan suhu 500°C selama 1 jam dan laju pemanasan 1°C/menit. Hasil brown part kemudian disintering dengan atmosfer argon pada suhu 1150°C, 1250°C, dan 1350°C selama 2 jam. Karakterisasi SEM-EDS, TGA, OM, densitas serta kekerasan dilakukan untuk menganalisis hasil sinter yang diperoleh. Fasa yang diperoleh dari hasil argon sintering adalah α dan β titanium. Densitas relatif yang diperoleh pada proses sintering sebesar 98.50%, 94.33%, dan 96.37% dengan nilai kekerasan berturut-turut 320, 315, dan 335 HV.

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Titanium alloy Ti6Al4V is a material that has a good combination of mechanical properties for implants such as good ductility, high corrosion resistance and good biocompatibility, so it is widely used as a material for biomedical implant applications. One method that is currently widely used to produce Ti6Al4V implants is by using the metal injection molding (MIM) process. The MIM process is widely used because it can produce parts more effectively, and production costs are cheaper. One of the important factors in the MIM process is good feedstock preparation and determining the optimum process parameters to prevent the formation of a TiO2 oxide layer on the MIM product because it will affect the mechanical properties of the alloy. This study aims to determine the effect of the process parameters at each stage of the MIM on the final product injection. The Ti6Al4V feedstock was injected at a temperature of 200°C and a pressure of ±2100 psi then removed the binder with solvent debinding using n-hexane at a temperature of 50°C for 1, 2, and 3 hours, and continued with thermal debinding at 2 different atmosphere variations, namely vacuum and argon at a temperature of 500°C for 1 hour and a heating rate of 1°C/minute. The resulting brown part was then sintered in an argon atmosphere at temperatures of 1150°C, 1250°C, and 1350°C for 2 hours. Characterization of SEM-EDS, TGA, OM, density and hardness was carried out to analyze the sintered results obtained. The phases obtained from argon sintering are and titanium. The relative densities obtained in the sintering process were 98.50%, 94.33%, and 96.37% with hardness values of 320, 315, and 335 HV, respectively."

"Produk plastik merupakan produk yang paling sering digunakan di masyarakat saat ini, dalam proses pembuatan platik secara injeks umumnya menggunakan metode injeksi secara konvensional terutama pada proses perpindahan panasnya, kualitas permukaan dan waktu siklus produk manufaktur cetakan injeksi sangat dipengaruhi oleh sistem pendingin, dan sekitar 70 waktu siklus%, waktu pembuatan produk yang digunakan untuk transfer panas. pada insert cetakan injeksi konvensional BeCu biasa digunakan untuk mempercepat proses pendinginan dan penyeragaman suhu. Penelitian ini membandingkan penggunaan Vapor Chamber dan BeCu insert dalam cetakan injeksi, dengan variasi suhu inlet, laju aliran pendinginan, serta suhu pendinginan yang berbeda. Vapor chamber terbukti efektif untuk mempercepat proses perpindahan panas dalam cetakan injeksi hingga 67% dibandingkan dengan metode pendinginan konvensional, nilai dari uap ruang tahanan termal juga 20% lebih rendah dibandingkan dengan BeCu insert.

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Conventional plastic injection mold is the most common process used to produce plastic product, the surface quality and cycle time of plastic product is strongly influenced by the cooling system, and approximately 70% cycle time, is used cooling. on conventional injection mold, inserts from BeCu commonly used to speed up the process of cooling and uniform temperature. This study compared the use of BeCu and Vapor chamber as an insert, the heat supplied by the heater at the top, the bottom there are cooling. heat is given according to the injection molding sequences, variation used is the amount of heat input, cooling temperature and cooling rate. Vapor chamber used is made with copper foam wick with porous diameter 0.2 mm, filling ratio of 30%, and water as working fluid. Vapor chamber proved effective to speed up the process of heat transfer in injection mold up to 67% compared to conventional cooling methods using BeCu. at various inlet temperature, cooling flow rate and temperature, vapor chamber still able to speed up the cooling process."

"ABSTRAKPenelitian ini bertujuan untuk memperbaiki waktu changeover mold dalam studi kasus proses injeksi plastik. PT XYZ sebagai produsen sepeda motor memiliki seksi injeksi plastik yang memproduksi part plastik untuk sepeda motor. Sebuah mesin injeksi digunakan untuk memproduksi lebih dari satu jenis part, sehingga pergantian jenis part membutuhkan proses changeover. Proses changeover yang sering dilakukan menghasilkan waste bagi PT XYZ berupa waktu mengganggur. Penelitian ini menggunakan metode Single Minute Exchange of Dies (SMED) untuk mengurangi durasi pelaksanaan changeover secara signifikan. Penelitian dilakukan sesuai dengan tiga tahap metode SMED yaitu mengelompokkan aktivitas ke dalam setup internal dan setup eksternal, mengkonversi aktivitas internal menjadi aktivitas eksternal, dan memperlancar seluruh pelaksanaan aktivitas setup. Langkah perbaikan pada tahap ketiga disimulasikan dengan simulasi Monte Carlo pada Ms. Excel. Hasil penelitian menunjukkan bahwa metode SMED dapat mengurangi waktu changeover sebesar 42,86%. Pengurangan ini berdampak pada penurunan waktu menggangur sebesar 760,77 menit dan peningkatan produktivitas sebesar 1.030 part dalam waktu satu bulan.

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ABSTRACTThis research aims to improve mold changeover time on plastic injection molding case. PT XYZ as a motorcycle manufacturer has a plastic injection section which produces plastic parts for motorcycle body. An injection machine is used to produce more than one part type, so changeover process is needed. The frequent changeovers result in idle time waste for the company. The research uses Single Minute Exchange of Dies (SMED) method to reduce changeover time significantly. The research was conducted based on three steps of SMED, namely, separating internal and external setup, converting internal to external setup, and streamlining all aspects of the setup operation. Improvement actions on the third step were simulated by Monte Carlo simulation in MS. Excel. The result showed that SMED is capable to reduce changeover time by 42.86%. This leads to 760.77 minutes of idle time reduction and an increase in productivity by 1,030 parts within one month."