Divertor plasma conditions and their effect on carbon migration in the ASDEX Upgrade tokamak

Divertors play a critical role in power and particle exhaust and plasma-material interaction in tokamaks. Of particular concern is the release of impurities from the material components, which reduces the lifetime of the vessel wall and affects the fusion performance. Furthermore, impurities with low charge number can migrate and re-deposit forming potentially tritium-rich layers in the tokamak. Sophisticated numerical simulations are required to understand how the various complex and often nonlinear processes in the plasma boundary affect the divertor performance. This thesis investigates the plasma conditions and the migration of impurities in the divertor region, using numerical code packages with the most complete available description of the relevant physical processes. It is known from earlier studies that the codes have both weaknesses and uncertainties in their models, which limits our current predictive capabilities. In this thesis work, carbon injection experiments at the ASDEX Upgrade tokamak are modelled. The work assesses the present-day boundary plasma models and elucidates impurity migration processes by comparing the simulations with experimental data. The results show that both the local migration and the net erosion of carbon are sensitive to the divertor plasma conditions. Good agreement between the modelled and measured divertor plasma parameters is obtained for a limited operational regime at low density. In this regime, the measured carbon migration is also reproduced in the simulations, and it is shown to be significantly affected by the electric field and the collisionality of the plasma in the divertor region. A significant improvement in code-experiment agreement is obtained after drifts arising from electric and magnetic fields are included in both plasma and impurity simulations. At higher plasma densities, collisionless hot electrons are a potential explanation for the deficiencies observed when benchmarking the plasma models against experiments

PENDIDIKAN ISLAM ERA RASULULLAH SEBAGAI REFLEKSI PENDIDIKAN ISLAM KEKINIAN

The Islamic education in the era of Rasulullah was known as an ideal Islamic education even though it wascarried out in circumstances and limitations. Islamic education in the era of Muhammad has proven successfulin giving birth to a golden generation in the Islamic world. This is inversely proportional to contemporary Islamiceducation which with various facilities and adequate learning media has given birth to some individuals whoembarrass the Islamic world itself. This paper aims to reflect on the era of the Prophet’s education to improvethe current state of Islamic education, ranging from educational institutions, educational goals, educationmethods to Islamic education material itself. With the hope of minimizing corruption and immoral acts committedby individuals who are alumni of Islamic education institutions and can revive the marwah of Islamic educationin the proper and proper position as aspired by the Prophet.Key Word: Pendidikan Islam, Era, Refleksi, Kekinian AbstrakPendidikan Islam di era Rasulullah dikenal sebagai pendidikan Islam yang ideal walaupun dilaksanakan dalamkeadaan serta keterbatasan. Pendidikan Islam era Rasulullah telah terbukti berhasil melahirkan generasi emasdalam dunia Islam. Hal itu berbanding terbalik dengan pendidikan Islam kekinian yang dengan berbagai fasilitasdan media pembelajaran yang memadai telah melahirkan beberapa oknum yang membuat malu dunia Islam itusendiri. Tulisan ini bertujuan untuk merefleksikan pendidikan era Rasulullah untuk memperbaiki keadaan duniapendidikan Islam kekinian, mulai dari lembaga pendidikan, tujuan pendidikan, metode pendidikan sampai padamateri pendidikan Islam itu sendiri. Dengan harapan dapat meminimalisir tindakan korupsi dan asusila yangdilakukan oleh oknum yang merupakan alumni lembaga pendidikan Islam dan dapat mengangkat kembalimarwah pendidikan Islam pada posisi yang seharusnya dan selayaknya sebagaimana yang dicita-citakanRasulullah.Kata Kunci: Pendidikan Islam, Era, Refleksi, Kekinia

GAYA BELAJAR DAN KOMPETENSI PEDAGOGIK GURU DAN DAMPAKNYA TERHADAP HASIL BELAJAR SISWA

This research was conducted with the following objectives: (1) is there any influence of learning styles on students’ result of study class X IPS SMA Negeri 4 Palangkaraya. (2) Is there any influence of Competence Pedagogical IPS Teacher on students’ result of study class X IPS SMA Negeri 4 Palangkaraya.3) Is there a simultaneous effect between students' learning styles and Pedagogic Competence IPS Teacher towards on students’ result of study class X IPS SMA Negeri 4 Palangkaraya. The population of this study were students of Class X IPS SMA Negeri 4 Palangkaraya which consisted 203 students. The sample was taken by purposive sampling from each class as much as 30% of the number of students which consists of 60 students.  The results showed that Competencies Pedagogical IPS teacher had no significant effect, which means that in this case variations in approach to teaching methods that teachers do not influence on students’ result of study class X IPS SMA N              egeri 4 Palangkaraya. (2) The style of learning is no significant effect on students’ result of study class X IPS SMA Negeri 4 Palangkaraya. (3) Teachers Pedagogic Competence IPS and learning styles do not have a positive effect and are not significant on students’ result of study. So that changes in the level Pedagogic Competence IPS Teacher and learning style will not change students’ result of the study

Urgensi Kurikulum Integrasi di Pondok Pesantren dalam Membentuk Manusia Berkualitas

Derasnya arus globalisasi dan modernisasi menjadi tantangan tersendiri bagi dunia pendidikan, termasuk pesantren. Globalisasi dan modernisasi memang dapat mendonkrak pendidikan ke arah kemajuan, namun kehadirannya perlu disikapi dengan langkah bijak agar tidak berdampak negatif terhadap pesantren. Menyikapi arus globalisasi dan modernisasi dapat dilakukan dengan inovasi pesantren terutama pengembangan kurikulumnya. Pengembangan kurikulum dapat dilakukan dengan mengintegrasikan kurikulum pesantren dengan kurikulum umum atau pemerintah yang mutlak menjadi kebutuhan santri untuk bersaing di dunia nyata di masyrakat. Dibukanya lembaga pendidikan formal di pesantren mulai dari tingkat sekolah dasar hingga perguruan tinggi merupakan contoh terlaksananya integrasi kurikulum di pesantren. Dengan kurikulum integrasi menjadikan santri mampu berkiprah di tengah kerasnya arus globalisasi dan modernisasi. Kurikulum pesantren juga dapat dikembangkan dengan menggunakan kurikulum berbasis kecakapan hidup (life skills), dimana santri dikekali dengan kemampuan dalam memecahkan berbagai masalah hidup dan keterampilan-keterampilan tertentu seperti pertanian, pengembangan ekonomi, elektronik, montir, industri rumah tangga, dan usaha produktif lainnya.The isnsitence of globalization and modernization become achallange to education, include pesantren. Globaliation and modernization in one side can advance education it self, but its existence must be responded wisely in order to not bring up negatif impact to the pesantren. Pesantren can respond the globalization and modernization current by innovate pesantren especially in curriculum development. The development of curriculum can be taken by integrate curriculum pesantren with goverment curriculum which is absolut neccesity for the santri to compete in real world in the community. Openning formal education from primary school until university is one of way the executed of integrated curriculum in pesantren. With the integrated curriculum makes santri can tak part in their world in gloabalization and modernization pressure.. Curriculum pesantren also can be developed using curriculum based on life skills curriculum which is provide santri ablity in solve poblems in their live and several skills like agriculture, economi, mechanic, domestic industry, and other produktif enterprise

Parametric scaling of power exhaust in EU-DEMO alternative divertor simulations

Investigations of parametric scaling of power exhaust in the alternative divertor configuration (ADC) SOLPS-ITER simulation database of the EU-DEMO are conducted and compared to predictions based on the Lengyel model. The Lengyel model overpredicts the necessary argon concentrations for LFS divertor detachment by about a factor of 5-10 relative to the SOLPS-ITER simulations. Therefore, while the Lengyel model predicts that plasmas with accetable divertor heat loads in EU-DEMO would exceed the tolerable upstream impurity concentrations by a large margin, there are several SOLPS-ITER solutions within an acceptable operational space. The SOLPS-ITER simulations indicate that, unlike assumed by the standard Lengyel model, there are significant heat dissipation mechanisms other than argon radiation, such as cross-field transport, that reduce the role of argon radiation by a factor of 2 to 3. Furthermore, the Lengyel model assumes that the radiation front is powered by parallel heat conduction only, which tends to lead to a narrow radiation front as the radiative efficiency increases strongly with reducing thermal conductivity. As a result, the radiative volume and total impurity radiation are suppressed for a given impurity concentration. However, the SOLPS-ITER simulations indicate that other mechanisms, such as cross-field transport, can compete with parallel heat conduction within the radiative front and increase the radiative volume. Due to these findings, usage of the standard Lengyel model for analyzing scaling between divertor conditions and configurations for devices such as EU-DEMO is strongly discouraged

Experimental Validation of a Filament Transport Model in Turbulent Magnetized Plasmas

In a wide variety of natural and laboratory magnetized plasmas, filaments appear as a result of interchange instability. These convective structures substantially enhance transport in the direction perpendicular to the magnetic field. According to filament models, their propagation may follow different regimes depending on the parallel closure of charge conservation. This is of paramount importance in magnetic fusion plasmas, as high collisionality in the scrape-off layer may trigger a regime transition leading to strongly enhanced perpendicular particle fluxes. This work reports for the first time on an experimental verification of this process, linking enhanced transport with a regime transition as predicted by models. Based on these results, a novel scaling for global perpendicular particle transport in reactor relevant tokamaks such as ASDEURATOM 63305

ELM-induced cold pulse propagation in ASDEX Upgrade

In ASDEX Upgrade, the propagation of cold pulses induced by type-I edge localized modes (ELMs) is studied using electron cyclotron emission measurements, in a dataset of plasmas with moderate triangularity. It is found that the edge safety factor or the plasma current are the main determining parameters for the inward penetration of the T-e perturbations. With increasing plasma current the ELM penetration is more shallow in spite of the stronger ELMs. Estimates of the heat pulse diffusivity show that the corresponding transport is too large to be representative of the inter-ELM phase. Ergodization of the plasma edge during ELMs is a possible explanation for the observed properties of the cold pulse propagation, which is qualitatively consistent with non-linear magneto-hydro-dynamic simulations.Peer reviewe

The operational space for divertor power exhaust in DEMO with a super-X divertor

SOLPS-ITER simulations of the European DEMO reactor with a Super-X divertor, which has larger major radius at the outer target and increased connection length, show an increased operational space for divertor power exhaust compared to the conventional single-null configuration. Using a multi-fluid approach with fluid neutrals and charge-state bundling of impurities, we assessed the existence and boundaries of the operational space in the single-null and Super-X configurations by carrying out fuelling, seeding and power scans. Compared to the conventional single-null divertor, the Super-X divertor offers lower impurity concentration (factor ∼2 lower) at the same main plasma density, and consistent with this, it has lower main plasma density at the same impurity concentration level. This observed difference is in line with the simple analytical Lengyel model predictions resulting from the increased connection length in the super-X configuration. DEMO with a Super-X divertor demonstrates remarkable robustness against increases in input power, and in this study is able to exhaust the maximum expected steady-state separatrix-crossing power of 300 MW while maintaining acceptable impurity concentration along the separatrix This is something that was not possible in the single-null configuration in this study. This robustness of the Super-X divertor lies mostly in its capability to sufficiently dissipate power in its divertor via argon (Ar) radiation at acceptable Ar concentration, which is related to two factors: long (with respect to single-null) parallel connection length from the upstream to the outer target and higher but tolerable extrinsic impurity concentration at higher input powers. Finally, consistent with neon-seeded simulations of ITER, it is observed in all our simulations that the plasma density drops with increasing Ar concentration given fixed power input. We find that as the Ar content increases, the accompanying enhancement of Ar radiation reduces the power available for deuterium (D) to be ionized, thus limiting the D ionization particle source, and consequently reducing the plasma density

Overview of the JET results in support to ITER

The 2014-2016 JET results are reviewed in the light of their significance for optimising the ITER research plan for the active and non-active operation. More than 60 h of plasma operation with ITER first wall materials successfully took place since its installation in 2011. New multi-machine scaling of the type I-ELM divertor energy flux density to ITER is supported by first principle modelling. ITER relevant disruption experiments and first principle modelling are reported with a set of three disruption mitigation valves mimicking the ITER setup. Insights of the L-H power threshold in Deuterium and Hydrogen are given, stressing the importance of the magnetic configurations and the recent measurements of fine-scale structures in the edge radial electric. Dimensionless scans of the core and pedestal confinement provide new information to elucidate the importance of the first wall material on the fusion performance. H-mode plasmas at ITER triangularity (H = 1 at beta(N) similar to 1.8 and n/n(GW) similar to 0.6) have been sustained at 2 MA during 5 s. The ITER neutronics codes have been validated on high performance experiments. Prospects for the coming D-T campaign and 14 MeV neutron calibration strategy are reviewed.Peer reviewe