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"The transportation or railway system constructors usually, wherever possible, build the transportation system on the ground surface and avoid the necessity of underground tunnelling. However, this is not always possible. In many locations, such as mountainous area, hilly area or urban area, the underground tunnelling have to be built. The main problem of underground tunnelling is the soil stability around the tunnel, and the problems continue to mount for long and big tunnel. Therefore in recent years, engineers try to find the method to predict and solve all aspect of ground responses induced by excavating and tunnelling.

For the past 30 years, the research for estimating an accurate prediction of ground deformation caused by tunnelling processes, have been a major engineering challenge all around the world. A good prediction of ground deformation due to tunnelling excavation and advancement is highly necessary to ensure that no damage will occur in the existing buildings and services at the surrounding area.

In this study, the excavation and advancement of tunnelling excavation in Tunnel TGV of Tartaiguille, France is modeled and analyzed using the numerical program in order to simulate the ground response due to the construction processes. On the other hand, CETU (Centre d'Etudes des Tunnels) had set out an instrumentation in sections of the tunnel in order to analyze the loading of the support of the tunnel and obtained the displacement of surrounding ground responses. The numerical simulation will take into account the visco plastic behavior of the soil. And then the result of numerical simulation will be compared to the field measurement data.

The constitutive model used in this study is an elasto-plastic constitutive model called CJS 2EC which has been developed by Ecole Centrale de Lyon. To lake into account the time-dependent behavior of the soil, the visco-plastic constitutive model has been embedded in the CJS 2EC model.

Hopefully with this study, we are getting one step ahead in estimating the ground responses in tunneling. The more realistic behavior of the soil around the tunnel, which include the time dependent behavior of the soil will be examined and gives an accurate prediction of ground response due to tunnelling excavation.

Observation of the results and comparison with the measurement data demonstrate that the time dependent behavior of soil cannot be neglected in the analysis of the tunnelling excavation."

"Tunnel Field Effect Transistor (TFET) merupakan struktur divais yang menggunakan mekanisme transport band-to-band tunneling untuk proses injeksi carrier. Hal ini berbeda dengan MOSFET yang menggunakan thermionic emission untuk mengalirkan arus. Dengan mekanisme transport yang berbeda ini,TFET dapat mencapai nilai subthreshold swing (SS) lebih rendah dari 60 mV/dec, lebih kecil dari transistor konvensional. Rendahnya nilai SS ini penting untuk penskalaan tegangan dengan arus switching yang ideal. Pada tesis ini dilakukan analisa karakteristik tunnel FET pada divais Si lateral p-n dan p-i-n berskala nanodari data hasil penelitian yang diperoleh Nano Device Laboratory, Research Institute of Electronics, Shizuoka University, Jepang. Fenomena band-to-band tunneling pada divais lateral p-n dan p-i-n berskala nano berhasil diobservasi. Band-to-band tunneling terjadi pada saat divais diberikan tegangan reverse bias dan gate diberikan tegangan positif. Dari hasil analisa pada struktur p-n dengan ketebalan oxide 150 nm, diperoleh SS mencapai 647,5 mV/dec. Dengan metode komparasi tegangan substrat pada ketebalan oxide 3 nm diperoleh SS sebesar 12,95 mV/dec, lebih kecil dari 60 mV/dec yang merupakan batasan nilai SS yang dapat dicapai pada MOSFET. Selanjutnya dilakukan analisa pengaruh co-doped dan intrinsic region terhadap tegangan threshold dan pengaruh panjangnya terhadap SS. Diperoleh bahwa struktur p-n memiliki tegangan threshold lebih tinggi dibanding struktur p-i-n. Hal ini dipengaruhi oleh level Fermi pada channel region, di mana co-doped region memiliki level Fermi EF = 0,112 eV, lebih rendah dari i-region dengan EF = 0,56 eV, sehingga dibutuhkan tegangan gate yang lebih besar untuk menurunkan energi band channel sehingga terbentuk tunnel junction. Dengan mengubah panjang co-doped dan i-region diperoleh hasil bahwa pada struktur p-n dengan panjang co-doped 250 nm diperoleh SS sebesar 647,5 mV/dec, lebih kecil dari struktur dengan panjang co-doped 1000 nm dengan SS mencapai 724 mV/dec. Hal ini disebabkan pada struktur p-n, co-doped region yang lebih pendek akan membentuk channel region yang lebih sempit sehingga elektron pada channel akan lebih cepat tersapu menuju drain. Sebaliknya, pada struktur p-i-n dengan panjang i-region 2000 nm diperoleh SS 704 mV/dec, lebih kecil dari struktur dengan panjang i-region 1000 nm dengan SS mencapai 776 mV/dec. Hal ini dapat dijelaskan bahwa pada struktur p-i-n, semakin panjang i-region maka daerah deplesi pada channel semakin lebar sehingga tunnel region yang terbentuk akan lebih panjang dan probabilitas elektron yang dapat dilewatkan pada tunnel region semakin besar.

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Tunnel Field Effect Transistor (TFET) is a device structure which use band to band tunneling transport for the carrier injection mechanism, unlike MOSFET which use thermionic emission. This transport mechanism enables TFET to reach sub threshold swing (SS) less than 60 mV/dec that can enable voltage scaling with ideal current switching. Analysis of the characteristic of tunnel FET on Si nanoscale lateral p-n and p-i-n devices will be conducted in this thesis based on the research data at Nano Device Laboratory, Research Institute of Electronics, Shizuoka University, Japan. Band to band tunneling phenomenon on the lateral nanoscale lateral p-n and p-i-n devices are successfully observed. Band to band tunneling occurs when the devices are in reverse biased condition and positive voltage is applied to the gate. For p-n device with the oxide thickness 150 nm, the SS reaches 647,5 mV/dec. Using substrate voltage comparison methods on the oxide layer with thickness of 3 nm, the SS value is 12,95-mV/dec, smaller than 60 mV/dec as a limitation of SS on MOSFET. Next, we analyze the effect of codoped and intrinsic region to the threshold voltage and its length to the subthreshold swing (SS).

We found that, p-n devices have higher threshold voltage compared to p-i-n devices. We ascribe that this results come from the fact that codoped region has lower Fermi level than that in i-region. By varying the intrinsic and the co-doped region length, we observed that p-n device with co-doped length 250 nm has SS 647,5 mV/dec, smaller than p-n device with co-doped length 1000 nm which has SS 724 mV/dec. We consider that when the co-doped region length is decreasing, the channel region will be shorter. Therefore the electron on the the conduction band of the channel will be swept out to the drain region quickly. We also found that, p-i-n device with i-region length 2000 nm has SS 704 mV/dec, smaller than p-i-n device with i-region length 1000 nm with SS 776 mV/dec. We ascribe that when the i-region length is increasing, the tunnel region in the channel region will be larger, such that the probabilities of electron to tunnel to the channel region increases."

"This book was inspired by the general observation that the great theories of modern physics are based on simple and transparent underlying mathematical structures – a fact not usually emphasized in standard physics textbooks – which makes it easy for mathematicians to understand their basic features. It is a textbook on quantum theory intended for advanced undergraduate or graduate students: mathematics students interested in modern physics, and physics students who are interested in the mathematical background of physics and are dissatisfied with the level of rigor in standard physics courses. More generally, it offers a valuable resource for all mathematicians interested in modern physics, and all physicists looking for a higher degree of mathematical precision with regard to the basic concepts in their field."

"Indonesia mengembangkan teknologi terowongan dikarenakan banyaknya kontur pegunungan dan kondisi geologi yang kaya akan mineral, serta untuk mengatasi permasalahan kemacetan di kota-kota besar. Terowongan merupakan salah atu alternatif prasarana perhubungan masa depan yang memungkinkan untuk mempersingkat waktu perjalanan. Konstruksi terowongan sendiri merupakan jenis konstruksi yang kompleks dan membutuhkan kemampuan manajerial dan teknikal yang tinggi dalam pengerjaannya. Oleh karena itu, diperlukan perencanaan yang sangat baik dan detail pada setiap proyek terowongan. Tujuan dari penelitian ini adalah untuk menghasilkan kamus WBS dan checklist untuk konstruksi terowongan, sehingga dapat diidentifikasi faktor dominan apa saja yang berpengaruh pada kinerja K3. Penelitian ini terdiri dari beberapa tahap dengan metode kualitatif. Metodologi yang digunakan adalah validasi ahli, survei responden dan wawancara dan dianalisis menggunakan analisis deskriptif data modus. Dari penelitian ini, akan menghasilkan kamus WBS dan checklist dan faktor risiko dominan pada pekerjaan terowongan.

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Indonesia is developing the technology of tunnel construction because of many mineral problems, topography, and to overcome the problem of congestion in big cities. Tunnel is an alternative transportation infrastructure of the future that allows to shorten travel time. The tunnel construction itself consists of complex types of construction and requires high managerial and technical capabilities in the process. Therefore, good and detailed planning is needed for each tunnel project. The purpose of this study is to produce a WBS dictionary and checklist for tunnel construction, so as to identify what dominant factors are successful in K3 performance. This research consists of research with qualitative methods with the methodology used is expert validation, respondent surveys and interviews and analyzed using descriptive data mode analysis."