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"The dual-inverter fed open-end winding configuration can be categorized as a new breed of multi-level converters. The structure is simple and offers a lot of advantages. However, the development of suitable PWM schemes is more complicated, due to the availability of a large number of switching states and existence of the multiple two-dimensional planes. An overview of attempts to develop suitable modulation techniques for the dual-inverter fed five-phase machine drives recognizes that progress has been made over the past few years. This paper presents a performance comparison of three PWM schemes of the dual-inverter fed five-phase, open-end winding motor drives. The quality of the phase output voltages are compared and the adequate analyses are provided. The simulation results show that the Carrier Based Phase Disposition (PD) PWM scheme enables generation of the most excellent output voltage among the three PWM schemes. The Total Harmonics Distortion (THD) of the output voltages generated by the carrier based PWM scheme reduces by 65% and 15% on average compared to the THD of the output voltages produced by the URS PWM scheme and the decomposition PWM scheme respectively."

"This paper analyzes voltage space vectors’ utilization of various Pulse Width Modulation (PWM) schemes in dual-inverter fed five-phase open-end winding motor drives with equal DC-link voltage. The applied voltage space vectors in three PWM schemes were examined. These three schemes were: the Equal Reference Sharing (ERS) PWM, the Unequal Reference Sharing (URS) PWM, and the Decomposition PWM. The results of these examinations show that the ERS scheme utilizes only 21 of the 211 available voltage vectors, and that the URS scheme utilizes more voltage vectors than the ERS scheme. The number of vectors applied in the URS scheme varies according to the modulation index and angular position of the voltage references. Consequently, the URS scheme produces better voltage output quality than the ERS scheme. Of the three schemes, the Decomposition PWM applies the most effective voltage vectors and produces the best voltage output quality, which is indicated by the lowest value of Total Harmonics Distortion (THD). This paper also proposes a new switching strategy that inherently improves the power sharing capability of the converter, thus avoiding the increase in the DC-link voltage of inverter that operates in PWM mode."

"Pembelajaran anatomi dalam pendidikan kedokteran sering menggunakan kadaver. Usai digunakan, kadaver dikebumikan dengan metode deep burial. Hal ini menyebabkan pencemaran tanah yang terjadi akibat penggunaan formalin. Salah satu bahan alternatif formalin yang banyak diteliti adalah etanol-gliserin. Penelitian ini membandingkan tingkat dekomposisi tungkai belakang mencit Mus musculus yang telah diawetkan dengan etanol-gliserin dan formalin 4%. Mencit diawetkan terlebih dahulu dengan fiksatif primer formalin 10% yang menjadi standar pengawet kadaver, diikuti perendaman dengan fiksatif lanjut yaitu etanol-gliserin atau formalin 4%. Setelah itu, mencit dikebumikan selama 6 minggu dan dilihat tingkat dekomposisinya per minggu. Tingkat dekomposisi dinilai secara semikuantitatif dari penampilan, bau, dan keberadaan organisme pengurai. Data yang diperoleh menunjukkan bahwa terdapat perbedaan tingkat dekomposisi tungkai bawah mencit antar larutan fiksatif lanjut, dimana pada minggu ke-6 kelompok EG sampai pada tahap dry and remains sementara kelompok formalin masih berada di tahap advanced decay. Dapat disimpulkan bahwa, tungkai belakang mencit yang diawetkan dengan larutan fiksatif etanol gliserin memiliki tingkat dekomposisi yang lebih cepat dibandingkan dengan larutan formalin 4%.

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Medical schools often use cadavers as a tool for learning anatomy. Once used, the cadavers are buried using the deep burial method. This may cause soil contamination due to the use of formalin. Several research have found promising results on the use of ethanol-glycerin as an alternative fixative solution for formalin. This study compared the rate of decomposition between the two fixative solutions, ethanol-glycerine and 4% formalin, on the hind limb of mice. The mice was first preserved using a standard primary fixative solution which is 10% formalin, following that procedure is preservation using advanced fixative solution, ethanol- glycerine or 4% formalin. Upon completing the preservation steps, the mice were buried for a duration of 6 weeks and observed weekly. The stages of decomposition was assessed semiquantitively by physical observations, smell, and presence of decomposers. Data obtained showed that there was a difference in the rate of decomposition between the two advanced fixative solutions, where in the 6th week the hind limbs of mice in the EG group was able to reach the dry and remains stage while the formalin group was still in the advanced decay stage. It is concluded that, the hind limbs of mice that were previously preserved with ethanol-glycerine advanced fixative solution had a faster decomposition rate than 4% formalin."

"Beberapa studi eksperimental dan teoretis baru-baru ini mengungkapkan bahwa material dua dimensi (2D) merupakan kandidat yang menjanjikan untuk teknologi informasi berbasis seleksi derajat kebebasan elektron, spin, hingga valley, bergantung pada interaksinya dengan cahaya. Dalam hal ini, ada banyak material 2D yang perlu ditelusuri sifat elektronik dan sifat optiknya untuk mendapatkan polarisasi sifat fisis tertentu, terutama polarisasi valley yang terkait dengan seleksi derajat kebebasan keadaan elektron pada titik tertentu di ruang momentum. Melalui perhitungan first principles untuk monolayer α-Sb dan NbS2, kami memverifikasi kondisi material 2D yang dapat memiliki potensi untuk aplikasi valleytronics melalui polarisasi optik dari valley-nya. Penyerapan cahaya terpolarisasi melingkar oleh material dihitung melalui pendekatan dipol dengan menggunakan vektor dipol dan matriks elemen transisi optik. Kami menemukan bahwa elektron di valley yang berbeda pada zona Brillouin yang memenuhi simetri pembalikan waktu untuk monolayer α-Sb dan NbS2 dapat tereksitasi secara selektif oleh cahaya terpolarisasi melingkar kiri atau kanan. Khusus NbS2, intensitas maksimum polarisasi valley mencapai 100% di valley K atau K’ tergantung polarisasi cahaya melingkar (kanan atau kiri) yang diberikan. Selektivitas yang sangat baik ini diduga terkait erat dengan struktur kristal heksagon tertekuk (buckled) dengan ikatan polar yang dimiliki oleh NbS2 alih-alih struktur berkerut (puckered) dengan ikatan nonpolar dari α-Sb.

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Recent experimental and theoretical studies revealed that two-dimensional (2D) materials are a promising candidate for information technology based on selectivity of electron, spin, and valley degrees of freedom under interaction with light. In this case, there are a lot of 2D materials whose electronic and optical properties need to be investigated so that we can obtain polarization of certain physical properties, especially valley polarization which is related to the selection rule of electronic excitation by light at a certain point (the so-called valley) in momentum space. By using first-principles calculations for monolayer α-Sb and NbS2, we verify some conditions for 2D materials that are potential for valleytronics applications utilizing the optical valley polarization. In this case, we need to calculate the absorption of circularly polarized light by the materials through the dipole approximation which gives the dipole vectors and optical transition matrix elements as the main quantities to be investigated. We found that electrons at the different valleys, which satisfy time-reversal symmetry, in the Brillouin zone of monolayer α-Sb and NbS2, can be selectively excited by left-handed or right-handed circularly polarized light. Specifically for NbS2, the maximum intensity of valley polarization can reach 100\% at the K or K’ valley depending on the given (left-handed or right-handed) circular polarization of light. We expect that such an excellent selectivity in NbS2 is closely related to its buckled hexagonal lattice and polar bonding, in contrast to the puckered lattice and nonpolar bonding in α-Sb. "

"Formalin pada kadaver dapat menimbulkan masalah bagi sekitarnya, salah satunya memperlambat proses dekomposisi saat kadaver dikuburkan, sehingga perlu dilakukan penetralan. Salah satu senyawa yang dapat digunakan adalah ammonium klorida. Oleh karena itu, penelitian ini akan membandingkan kemampuan penetralan berbagai persentase larutan ammonium klorida terhadap formalin 4%. Penelitian ini menggunakan 18 ekor mencit (Mus musculus), dibagi menjadi tiga kelompok, yaitu mencit yang diawetkan dengan formalin 4%, mencit yang diawetkan dan diberikan penetral ammonium klorida 20%, dan mencit yang diawetkan dan diberikan penetral ammonium klorida 40%. Mencit kemudian dikebumikan selama 5 minggu dan dinilai tingkat dekomposisinya. Proses dekomposisi kelompok formalin 4% lebih cepat dibandingkan kelompok ammonium klorida 20% dan 40%. Tidak adanya perbedaan yang bermakna antara kelompok ammonium klorida 20% dan 40%. Peneliti menduga karena adanya pembentukan resin urea-formalin, serta pH tanah yang rendah juga menghambat perkembangan bakteri. Setelah itu, tidak dilakukan pengukuran kadar formalin di dalam jaringan sehingga masih ada kemungkinan terdapat formalin yang belum dinetralkan pada kelompok ammonium klorida 20% dan 40%, membuat tidak ada perbedaan antara kedua kelompok tersebut. Proses dekomposisi tungkai mencit yang diawetkan dengan formalin 4% lebih cepat dibandingkan yang dinetralkan dengan ammonium klorida. Tidak ada perbedaan antara proses dekomposisi antara tungkai mencit yang dinetralkan dengan ammonium klorida 20% dan 40%.

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Formaldehyde in cadavers can cause many problems to the environment, one of them is by decreasing the decomposition rate when cadavers were buried, hence needed to be neutralized. One of the ways is by using ammonium chloride. This study aims to compare between different neutralizing ammonium chloride concentrations on the decomposition of preserved hindlimb of mice. This study uses 18 mice (Mus musculus) divided into three study groups, which is mice that is preserved with 4% formaldehyde, mice that is preserved and neutralized by 20% ammonium chloride, and mice that is preserved and neutralized by 40% ammonium chloride. Afterwards, the mice will be buried for 5 weeks and evaluated by the decomposition. The decomposition of 4% formaldehyde group is faster than 20% and 40% ammonium chloride group. There is no significant difference between 20% and 40% ammonium chloride group. Researcher suspects that this is due to the formation of urea-formaldehyde resin, and low soil pH that inhibits bacterial growth. Other than that, formaldehyde levels in the tissue of the mice are not measured, so there is still a possibility that the formaldehyde has not been neutralized, causing no difference between the two groups. Decomposition process of hindlimb that is preserved by 4% formaldehyde is faster than hindlimb that is preserved and neutralized by ammonium chloride. There is no significant difference between decomposition process of preserved hindlimb that is neutralized by 20% and 40% ammonium chloride."

"Saat ini penggunaan dari motor induksi sangatlah luas. Untuk dapat bekerja sesuai dengan kebutuhan para penggunannya, peralatan elektronika daya, seperti PWM inverter, digunakan untuk mengendalikan dan memperluas daerah kerja dari motor induksi. Pengendalian motor induksi dengan menggunakan PWM inverter dapat dilakukan dengan mengatur nilai tegangan dan frekuensi masukan pada sisi stator dari motor induksi. Pada skripsi ini, karakteristik dari motor induksi dengan catu PWM inverter disimulasikan dengan menggunakan program SIMULINK dari MATLAB versi 7.1.0.246 (R14). Sebagian besar parameter yang digunakan pada pemodelan dari sistem disesuaikan dengan peralatan TecQuipment NE 7021 AC machine Console yang terdapat pada laboratorium Konversi Energi Listrik. Motor induksi yang digunakan adalah rotor tipe sangkar dan simulasi dilakukan dengan cara memvariasikan nilai frekuensi masukan stator dan juga indeks modulasi, dengan demikian akan didapatkan nilai torsi elektromagnetik dan kecepatan putar rotor dari motor induksi. Dari hasil simulasi tersebut akan dianalisa pengaruh frekuensi dan amplitudo tegangan masukan pada nilai torsi elektromagnetik dan kecepatan putaran rotor.

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Induction motors are broadly used recently. To work according to users requirements, power electronic equipments, like a PWM inverter, are used in controlling and expanding the working range of induction motors. Controlling induction motors using a PWM inverter is done by managing voltages and input frequencies to the induction motors stator.

In this bachelor's thesis, the characteristics of an induction motor fed by a PWM inverter is simulated using SIMULINK programs of MATLAB 7.1.0.246 (R14) version. Most of the parameters used in modeling the system are adjusted using TecQuipment NE 7021 AC machine Console equipment at the Electric Energy Conversion Laboratory. The induction motor is a squirrel cage type and simulation is done by varying stator input frequency values and also modulation indexes, thereby achieving electromagnetic torque values and rotor spin speeds of the induction motor. The results of these simulations will be analyzed to know the influence of input voltage frequency and amplitude on the electromagnetic torque and rotor turn speed values."

"ABSTRACTPembelajaran neuronatomi sangat membutuhkan kadaver terutama organ otak sebagai sarana pembelajaran. Hingga saat ini, pengawet paling umum yang digunakan adalah menggunakan cairan berbahan dasar formalin. Akan tetapi, kandungan formalin pada kadaver dapat menimbulkan berbagai efek yang merugikan bagi kesehatan manusia maupun lingkungan. Penelitian ini bertujuan untuk mengetahui perbandingan dekomposisi otak mencit yang diawetkan dengan cairan fiksatif formalin 4% dengan dan tanpa penambahan penetral formalin berbahan dasar gliserin. Penelitian ini menggunakan 18 ekor mencit (Mus musculus) yang dibagi secara acak menjadi 3 kelompok yaitu kelompok kontrol (tanpa pengawetan), kelompok yang hanya diawetkan dengan formalin 4%, dan kelompok yang diawetkan dengan formalin 4% ditambah dengan penetral gliserin. Penilaian tahapan dekomposisi dilakukan dengan skoring serta pengukuran massa total dan massa otak mencit yang dilakukan setiap minggu. Pada selisih massa otak mencit, didapatkan hasil berbeda bermakna pada minggu ke-2 pengukuran. Pada persentase selisih massa otak, didapatkan perbedaan bermakna antara kelompok formalin 4% dan gliserin dari seluruh waktu pengukuran. Dari penelitian ini dapat disimpulkan bahwa terdapat perbedaan dekomposisi antara otak mencit yang diawetkan dengan formalin 4% dengan dan tanpa penambahan cairan penetral formalin berbahan dasar gliserin dimana kelompok gliserin terdekomposisi lebih cepat.

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ABSTRACTNeuroanatomy learning requires cadaver, especially the brain, as a learning tool. Until now, the most common preservertive used was using formalin-based fixative liquids. However, formalin can cause various adverse effects to human health and to the environment. Therefore, we will compare the brain decomposition rate the mice preserved with of 4% formalin fixative liquid with and without addition of glycerin-based formalin neutralizer. This study used 18 mice (Mus musculus) which were randomly divided into 3 groups: control group with no additional fixative, group preserved with 4% formalin, and group preserved with 4% formalin, then neutralized with glycerin. Assessment of the stages of decomposition is done by scoring as well as measuring the total mass and brain mass of mice that are carried out every week. Difference in brain mass of mice only obtain significantly different results on the second week of measurement. In the percentage difference in brain mass, there were significant differences between the 4% formalin and glycerin in all measurement times. Therefore, there is a difference in the level of decomposition between the brains of mice preserved with 4% formalin with and without additional formalin neutralizer with glycerin content, whereas decomposition in glycerin group is faster."

"Transesophageal echocardiography (TEE) is a valuable diagnostic modality now routinely used during cardiac surgery and in the intensive care unit. Increasingly, anesthesiologists trained in TEE provide the service in both settings where they face the challenge of integrating numerous current TEE guidelines into day-to-day practice. Perioperative two-dimensional transesophageal echocardiography : a practical handbook has been designed to be a concise, portable guide for using TEE to recognize cardiac pathology during the perioperative period. This compact guide has a diverse appeal for anesthesiologists, cardiac surgeons, and cardiologists desiring comprehensive up-to-date echocardiographic information at their fingertips.Features :- More than 450 full-color, high quality clinical images and illustrations- Synopsis of cardiac pathology commonly encountered in cardiac surgery patients- Convenient spiral binding- On-the-spot reference for echocardiographers with a wide range of experience, from novice to expert"

"This book highlights the various types of polymer and nanocomposites that can be derived from biorenewable resources. It covers various aspects of biobased polymers and nanocomposites, including preparation, processing, properties, and performance, and the latest advances in these materials."