Resolving the fine-scale structure in turbulent Rayleigh-Benard convection

We present high-resolution direct numerical simulation studies of turbulent Rayleigh-Benard convection in a closed cylindrical cell with an aspect ratio of one. The focus of our analysis is on the finest scales of convective turbulence, in particular the statistics of the kinetic energy and thermal dissipation rates in the bulk and the whole cell. The fluctuations of the energy dissipation field can directly be translated into a fluctuating local dissipation scale which is found to develop ever finer fluctuations with increasing Rayleigh number. The range of these scales as well as the probability of high-amplitude dissipation events decreases with increasing Prandtl number. In addition, we examine the joint statistics of the two dissipation fields and the consequences of high-amplitude events. We also have investigated the convergence properties of our spectral element method and have found that both dissipation fields are very sensitive to insufficient resolution. We demonstrate that global transport properties, such as the Nusselt number, and the energy balances are partly insensitive to insufficient resolution and yield correct results even when the dissipation fields are under-resolved. Our present numerical framework is also compared with high-resolution simulations which use a finite difference method. For most of the compared quantities the agreement is found to be satisfactory.Comment: 33 pages, 24 figure

Quotient graphs for power graphs

In a previous paper of the first author a procedure was developed for counting the components of a graph through the knowledge of the components of its quotient graphs. We apply here that procedure to the proper power graph $\mathcal{P}_0(G)$ of a finite group $G$, finding a formula for the number $c(\mathcal{P}_0(G))$ of its components which is particularly illuminative when $G\leq S_n$ is a fusion controlled permutation group. We make use of the proper quotient power graph $\widetilde{\mathcal{P}}_0(G)$, the proper order graph $\mathcal{O}_0(G)$ and the proper type graph $\mathcal{T}_0(G)$. We show that all those graphs are quotient of $\mathcal{P}_0(G)$ and demonstrate a strong link between them dealing with $G=S_n$. We find simultaneously $c(\mathcal{P}_0(S_n))$ as well as the number of components of $\widetilde{\mathcal{P}}_0(S_n)$, $\mathcal{O}_0(S_n)$ and $\mathcal{T}_0(S_n)$

Waterbath Calibrator with Nine Channels Sensor

Water bath is a laboratory equipment that contains water or special liquid that can maintain the temperature under certain conditions during the specified time interval. For this reason, calibration is needed so that the temperature in the chamber waterbath is stable or not. calibration is carried out by comparing measuring instruments and measuring materials to be calibrated to traceable standards that are traceable to national and / or International standards. Based on the results of the identification of the problems mentioned above, the author makes a waterbath calibrator entitled "Waterbath Calibrator (9 channel)" which is very practical, and easy to operate. .This calibration tool uses a K type thermocouple sensor and also the output is displayed to the character LCD to make it easier for users to retrieve data, the reason for choosing a thermocouple sensor is because the error rate is +/- 1,1C while the LM35 is +/- 1,4C. The thermocouple temperature sensor can detect the chamber temperature quite well where the biggest error is obtained with a comparator of 2%, and the lowest error is 0%

Epigenetic Chromatin Silencing: Bistability and Front Propagation

The role of post-translational modification of histones in eukaryotic gene regulation is well recognized. Epigenetic silencing of genes via heritable chromatin modifications plays a major role in cell fate specification in higher organisms. We formulate a coarse-grained model of chromatin silencing in yeast and study the conditions under which the system becomes bistable, allowing for different epigenetic states. We also study the dynamics of the boundary between the two locally stable states of chromatin: silenced and unsilenced. The model could be of use in guiding the discussion on chromatin silencing in general. In the context of silencing in budding yeast, it helps us understand the phenotype of various mutants, some of which may be non-trivial to see without the help of a mathematical model. One such example is a mutation that reduces the rate of background acetylation of particular histone side-chains that competes with the deacetylation by Sir2p. The resulting negative feedback due to a Sir protein depletion effect gives rise to interesting counter-intuitive consequences. Our mathematical analysis brings forth the different dynamical behaviors possible within the same molecular model and guides the formulation of more refined hypotheses that could be addressed experimentally.Comment: 19 pages, 5 figure

"How May I Help You?": Modeling Twitter Customer Service Conversations Using Fine-Grained Dialogue Acts

Given the increasing popularity of customer service dialogue on Twitter, analysis of conversation data is essential to understand trends in customer and agent behavior for the purpose of automating customer service interactions. In this work, we develop a novel taxonomy of fine-grained "dialogue acts" frequently observed in customer service, showcasing acts that are more suited to the domain than the more generic existing taxonomies. Using a sequential SVM-HMM model, we model conversation flow, predicting the dialogue act of a given turn in real-time. We characterize differences between customer and agent behavior in Twitter customer service conversations, and investigate the effect of testing our system on different customer service industries. Finally, we use a data-driven approach to predict important conversation outcomes: customer satisfaction, customer frustration, and overall problem resolution. We show that the type and location of certain dialogue acts in a conversation have a significant effect on the probability of desirable and undesirable outcomes, and present actionable rules based on our findings. The patterns and rules we derive can be used as guidelines for outcome-driven automated customer service platforms.Comment: 13 pages, 6 figures, IUI 201

Penerapan Model Pembelajaran Inkuiri Terbimbing Dilengkapi Lks Untuk Meningkatkan Keterampilan Proses Sains Dan Prestasi Belajar Pada Materi Pokok Hukum Dasar Kimia Siswa Kelas X Mia 4 SMA N 1 Karanganyar Tahun Pelajaran 2014/2015

Tujuan penelitian ini adalah untuk meningkatkan keterampilan proses sains siswa dan prestasi belajar siswa pada materi hukum dasar kimia kelas kelas X MIA 4 SMA N 1 Karanganyar tahun pelajaran 2014/2015 dengan penerapan model pembelajaran inkuiri terbimbing dilengkapi LKS. Penelitian ini merupakan Penelitian Tindakan Kelas (PTK) yang dilaksanakan dalam dua siklus, dengan tiap siklus terdiri atas perencanaan, tindakan, observasi dan refleksi. Subjek penelitian ini adalah siswa kelas X MIA 4 SMA Negeri 1 Karanganyar tahun pelajaran 2014/2015 yang berjumlah 36 siswa. Sumber data berasal dari guru dan siswa. Teknik pengumpulan data dilakukan dengan tes dan non tes (angket, observasi dan wawancara). Analisis data menggunakan teknik analisis deskriptif kualitatif. Hasil penelitian menunjukan bahwa: (1) penerapan model pembelajaran inkuiri terbimbing dilengkapi LKS dapat meningkatkan keterampilan proses sains siswa pada materi hukum dasar kimia. Hal ini dapat dilihat ketuntasan siklus I yaitu 66,67% meningkat menjadi 77,78% pada siklus II, (2) penerapan model pembelajaran inkuiri terbimbing dilengkapi LKS dapat meningkatkan prestasi belajar siswa pada materi hukum dasar kimia. Prestasi belajar dalam penelitian ini berupa aspek pengetahuan, sikap dan keterampilan (praktik dan tertulis). Persentase prestasi belajar pada aspek pengetahuan untuk siklus I sebesar 69,44% meningkat menjadi 80,56% pada siklus II, ketuntasan penilaian aspek sikap siklus I dan II yaitu sebesar 100% dan ketuntasan pada aspek keterampilan yaitu sebesar 100%

Spontaneous emission by rotating objects: A scattering approach

We study the quantum electrodynamics (QED) vacuum in the presence of a body rotating along its axis of symmetry and show that the object spontaneously emits energy if it is lossy. The radiated power is expressed as a general trace formula solely in terms of the scattering matrix, making an explicit connection to the conjecture of Zel'dovich [JETP Lett. 14, 180 (1971)] on rotating objects. We further show that a rotating body drags along nearby objects while making them spin parallel to its own rotation axis

Improve Capability Process to Optimizing Productivity: Case Study Line Process Packing Assembly in Electronic Manufacturing Company

Six sigma is a method for improving processes that focus on reducing process variations using statistical approaches and effective problem solving. The purpose of this method is calculating the impact of six sigma applications to company productivity. Six sigma not only aims to achieve zero defect, with the Six Sigma method optimizing production (Productivity), Six sigma, supporting the proper procedures in line with business goals both system and process. With the DMAIC method, we get as much information as possible and as soon with the smallest sample unit of the experiment. From the results of the paper, Takt Time reduce, 9.2s à 8.5s proved by DMAIC analysis to get effective and efficient improvement that ultimately can improve the company\u27s efficiency