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"Predictive theories of phenomena involving phase change with applications in engineering are investigated in this volume, e.g. solid-liquid phase change, volume and surface damage, and phase change involving temperature discontinuities. Many other phase change phenomena such as solid-solid phase change in shape memory alloys and vapor-liquid phase change are also explored. Modeling is based on continuum thermo-mechanics. This involves a renewed principle of virtual power introducing the power of the microscopic motions responsible for phase change. This improvement yields a new equation of motion related to microscopic motions, beyond the classical equation of motion for macroscopic motions. The new theory sensibly improves the phase change modeling. For example, when warm rain falls on frozen soil, the dangerous black ice phenomenon can be comprehensively predicted. In addition, novel equations predict the evolution of clouds, which are themselves a mixture of air, liquid water and vapor."

"A state-of-the-art description of metastability observed in chalcogenide alloys is presented with the accent on the underlying physics. A comparison is made between sulphur(selenium)-based chalcogenide glasses, where numerous photo-induced phenomena take place entirely within the amorphous phase, and tellurides where a reversible crystal-to-amorphous phase-change transformation is a major effect. Applications of metastability in devices optical memories and nonvolatile electronic phase-change random-access memories among others are discussed, including the latest trends. Background material essential for understanding current research in the field is also provided."

"The objective of the present study is to investigate numerically the problem of melting phase change material (PCM) containing paraffin where one of the area interfaces moves with time and wherein the result of the fusion between the coupling in the solid phase conduction and convection in the liquid phase, then processes the effect of integration of the material in the walls of the building in order to increase its thermal inertia to validate the result ,we will study the numerically transient and performance of a fixed bed filled with uniform spheres, randomly arranged and each containing a (PCM). So we use a two-dimensional theoretical model applied in two separate phases; it was used to predict the temperature distribution of the fluid and the fusible material along the bed in the energy storage method."

"ABSTRAKTingginya angka kelahiran bayi prematur di Indonesia menyebabkan inkubator sangat diperlukan. Seiring dengan kemajuan teknologi, inkubator bayi menjadi semakin canggih yang mana membuat harganya semakin mahal. Distribusi listrik yang belum merata di Indonesia, menjadikan inkubator elektrik tidak efektif. Salah satu solusi yang aplikatif adalah penggunaan Phase Change Materials (PCM) sebagai elemen pemanas. Karena besarnya nilai kalor laten yang dimilikinya, PCM dapat menyuplai energi panas dalam waktu yang cukup lama. Penelitian ini bertujuan untuk mengetahui efektifitas dua jenis PCM sebagai elemen pemanas pada inkubator bayi, yaitu paraffin wax dan beeswax.Variasi yang dilakukan dalam pengujian ini adalah waktu, jenis PCM, dan wadah PCM. Pengujian dilakukan dengan memanfaatkan prototipe Inkubator Grashof Seri-F dan fenomena konveksi natural. Pengukuran temperatur dilakukan menggunakan termokopel di dalam ruang inkubator, pada PCM, dan pada dinding wadah PCM. Melalui pengujian ini dapat disimpulkan bahwa paraffin wax dan beeswax mampu bekerja sebagai elemen pemanas pada inkubator bayi, yang mampu menjaga kondisi pada ruang inkubator pada rentang 32°C – 36°C. Beeswax memiliki performa yang lebih handal dibandingkan dengan paraffin wax, karena beeswax memiliki efisiensi volumetris sebagai reservoir panas yang lebih baik. Hal ini ditunjukkan melalui percobaan dimana dengan volume yang sama, beeswax dapat mempertahankan suhu pada ruang bayi selama 2-3 jam lebih lama pada siang hari dan 1-2 jam lebih lama pada malam hari.

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ABSTRACTIndonesia’s high mortality rate of preterm birth causes the presence of infant incubator is very important. As the technology develops, infant incubator also becomes more developed which makes its price even higher. Furthermore, the electricity distribution issue in Indonesia makes electric incubator becoming less effective. One of the applicable solutions is the usage of Phase Change Materials (PCM) as heating element. Its high amount of latent heat makes it is capable of mantaining heat supply for a long time. The goal of this experiment is to find out the effectiveness of paraffin wax and beeswax as heating element for infant incubator.Time, kind of PCM, and placement method is three variations that is tested in this experiment. The experiment uses Grashof Incubator F-Series prototype and natural convenction phenomenon. Data gathering is completed by measuring the temperatures of incubator, PCM, and container’s surfaces using thermocouple. Based on this experiment, can be concluded that both paraffin wax and beeswax are capable for being used as incubator’s heating element, because they can maintain incubator’s temperature in range of 32°C-36°C. Beeswax has a better performance than paraffin wax because it has higher volumetric efficiency. This is showed by the result section which states that beeswax lasts 2-3 hours longer than paraffin wax during the day and 1-2 hour longer during the night."

"[Salah satu tantangan dalam meningkatkan standar kesehatan di Indonesia adalah masih tingginya angka kelahiran bayi prematur. Upaya penyelamatan bayiyang lahir prematur terhambat oleh beberapa faktor terutama faktor ekonomi yang disebabkan mahalnya biaya perawatan di ruang NICU rumah sakit. Selain itu, distribusi listrik yang belum merata menyebabkan sedikitnya rumah sakit yang menyediakan fasilitas inkubator terutama pada wilayah terpencil di Indonesia. Penggunaan Phase Change Materials dari kelompok organik sebagai elemen pemanas inkubator portable non-elektrik agar aman bagi pernafasan bayidan mudah pendistribusiannya menjadi salah satu alternatif upaya penyelamatan bayi prematur yang lahir terutama diwilayah yang belum dialiri listrik nasional. Eksperimen ini bertujuan mendapatkan masa PCM yang paling efisien sesuai Standar Nasional Indonesia untuk mendapatkan rentang waktu dan temperatur paling ideal bagi bayi prematur. Juga pengurangan masa PCM akan meringankan bobot inkubator secara total serta mengurangi biaya. Eksperimen dilakukan menggunakan prototype Inkubator Grashof seri-F yang memanfaatkan fenomena konveksi natural dalam proses pemanasan ruang inkubator. Temperatur diukur menggunakan termokopel tipe K yang dihubungkan pada Modul NI9211. Grafik pengukuran digambarkan oleh perangkat lunak Labview 8.5 yang diinstal pada Personal Computer Unit. Hasil eksperimen menunjukkan masa PCM jenis Beeswax sebesar 3kg adalah yang paling efisien dalam penggunaan energi. Aplikasi fin juga membantu mempersingkat waktu tunggu sebelum penggunaaninkubator dan distribusi panas yang lebih merata dalam ruang inkubator.

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One of the challenges in improving health standards in Indonesia is a high number of neonatal birth. Government efforts to save neonatals hampered by several factors especially economic factors caused by high cost of neonatals care in NICU room at the hospital. Moreover, the uneven of electricity distribution cause least hospitals providing incubator facilities, especially for remote areas in Indonesia.

The use of Phase Change Materials from the organic group as a heating element for portable non-electric incubator to be safe for the baby's breathing and

easy distribution into an alternative rescue efforts, especially premature babies born in the region that has not been electrified nationwide. Experiments aimed at finding the most efficient mass of PCM based on Indonesian National Standard to get the ideal time and temperature range for premature babies. PCM mass reduction also will lighten the weight of the incubator in total as well as reduce costs. Experiments conducted using prototype Incubator Grashof-F series which utilizes natural convection phenomena in the process of incubator space heating.

Temperatures were measured using a K-type thermocouple connected to the module NI9211. Measurement chart illustrated by Labview 8.5 software installed on the Personal Computer Unit. The experimental results indicate the mass of 3kg PCM types Beeswax is the most efficient in energy use. Applications fin also help

shorten the waiting time before the use of incubators and more even heat distribution within the incubator.;One of the challenges in improving health standards in Indonesia is a high

number of neonatal birth. Government efforts to save neonatals hampered by

several factors especially economic factors caused by high cost of neonatals care

in NICU room at the hospital. Moreover, the uneven of electricity distribution

cause least hospitals providing incubator facilities, especially for remote areas in

Indonesia.

The use of Phase Change Materials from the organic group as a heating

element for portable non-electric incubator to be safe for the baby's breathing and

easy distribution into an alternative rescue efforts, especially premature babies

born in the region that has not been electrified nationwide. Experiments aimed at

finding the most efficient mass of PCM based on Indonesian National Standard to

get the ideal time and temperature range for premature babies. PCM mass

reduction also will lighten the weight of the incubator in total as well as reduce

costs. Experiments conducted using prototype Incubator Grashof-F series which

utilizes natural convection phenomena in the process of incubator space heating.

Temperatures were measured using a K-type thermocouple connected to the

module NI9211. Measurement chart illustrated by Labview 8.5 software installed

on the Personal Computer Unit. The experimental results indicate the mass of 3kg

PCM types Beeswax is the most efficient in energy use. Applications fin also help

shorten the waiting time before the use of incubators and more even heat

distribution within the incubator., One of the challenges in improving health standards in Indonesia is a high

number of neonatal birth. Government efforts to save neonatals hampered by

several factors especially economic factors caused by high cost of neonatals care

in NICU room at the hospital. Moreover, the uneven of electricity distribution

cause least hospitals providing incubator facilities, especially for remote areas in

Indonesia.

The use of Phase Change Materials from the organic group as a heating

element for portable non-electric incubator to be safe for the baby's breathing and

easy distribution into an alternative rescue efforts, especially premature babies

born in the region that has not been electrified nationwide. Experiments aimed at

finding the most efficient mass of PCM based on Indonesian National Standard to

get the ideal time and temperature range for premature babies. PCM mass

reduction also will lighten the weight of the incubator in total as well as reduce

costs. Experiments conducted using prototype Incubator Grashof-F series which

utilizes natural convection phenomena in the process of incubator space heating.

Temperatures were measured using a K-type thermocouple connected to the

module NI9211. Measurement chart illustrated by Labview 8.5 software installed

on the Personal Computer Unit. The experimental results indicate the mass of 3kg

PCM types Beeswax is the most efficient in energy use. Applications fin also help

shorten the waiting time before the use of incubators and more even heat

distribution within the incubator.]"