Verifying Inevitability of Oscillation in Ring Oscillators Using the Deductive SOS-QE Approach

This article presents a deductive numeric-symbolic approach, using sum of squares (SOS) programming and quantifier elimination (QE). The authors take ring oscillator as an example to verify that it can start oscillating from all possible initial voltages

Long range magnetic ordering in a spin-chain compound, Ca3_3CuMnO6_6, with multiple bond distances

The results of ac and dc magnetization and heat capacity measurements as a function of temperature (T = 1.8 to 300 K) are reported for a quasi-one-dimensional compound, Ca$_3$CuMnO$_6$, crystallizing in a triclinically distorted K$_4$CdCl$_6$-type structure. The results reveal that this compound undergoes antiferromagnetic ordering close to 5.5 K. In addition, there is another magnetic transition below 3.6 K. Existence of two long-range magnetic transitions is uncommon among quasi-one-dimensional systems. It is interesting to note that both the magnetic transitions are of long-range type, instead of spin-glass type, in spite of the fact that the Cu-O and Mn-O bond distances are multiplied due to this crystallographic distortion. In view of this, this compound could serve as a nice example for studying "order-in-disorder" phenomena.Comment: Physical Review (in press

Verifying robust frequency domain properties of non linear oscillators using SMT

We present a novel mixed time and frequency domain approach to the formal verification of oscillators properties which are specified in the frequency domain. We use robust periodogram specification to specify the oscillator behaviour in the close vicinity of the limit cycle. Using SAT modulo ODE (SMO) for Bounded Model Checking (BMC) of the non-linear hybrid automata, we show that the oscillator hybrid timed traces satisfy frequency domain specifications

Magnetic frustration in a stoichiometric spin-chain compound, Ca3_3CoIrO6_6

The temperature dependent ac and dc magnetization and heat capacity data of Ca$_3$CoIrO$_6$, a spin-chain compound crystallizing in a K$_4$CdCl$_6$-derived rhombohedral structure, show the features due to magnetic ordering of a frustrated-type below about 30 K, however without exhibiting the signatures of the so-called "partially disordered antiferromagnetic structure" encountered in the isostructural compounds, Ca$_3$Co$_2$O$_6$ and Ca$_3$CoRhO$_6$. This class of compounds thus provides a variety for probing the consequences of magnetic frustration due to topological reasons in stoichiometric spin-chain materials, presumably arising from subtle differences in the interchain and intrachain magnetic coupling strengths. This compound presents additional interesting situations in the sense that, ac susceptibility exhibits a large frequency dependence in the vicinity of 30 K uncharacteristic of conventional spin-glasses, with this frustrated magnetic state being robust to the application of external magnetic fields.Comment: Physical Review (Rapid Communications), in pres

DeepColor: Reinforcement Learning optimizes information efficiency and well-formedness in color name partitioning

As observed in the World Color Survey (WCS), some universal properties can be identified in color naming schemes over a large number of languages. For example, Regier, Kay, and Khetrapal (2007) and Regier, Kemp, and Kay (2015); Gibson et al. (2017) recently explained these universal patterns in terms of near optimal color partitions and information theoretic measures of efficiency of communication. Here, we introduce a computational learning framework with multi-agent systems trained by reinforcement learning to investigate these universal properties. We compare the results with Regier et al. (2007, 2015) and show that our model achieves excellent quantitative agreement. This work introduces a multi-agent reinforcement learning framework as a powerful and versatile tool to investi- gate such semantic universals in many domains and contribute significantly to central questions in cognitive science

ANTIDIABETIC ACTIVITY OF NIGELLA SATIVA L. SEED POWDER AND ITS COMBINATION WITH GLICLAZIDE IN ALLOXAN INDUCED DIABETIC MICE

Objective: In Indonesia, Nigella sativa (NS) has been widely used for the treatment of diabetes mellitus. The aim of this study was to evaluate the antidiabetic activity of its seed powder and its combination with gliclazide. Methods: NS was used in seed powder suspension form. At study's begin, Oral Glucose Tolerance Test (OGTT) was performed. And then the mice were induced with 60 mg/kg alloxan intravenously and were treated with 1300 mg/kg NS (NS1), 2000 mg/kg NS (NS2), 0,65 mg/kg gliclazide, and combination of NS1-gliclazide that administered orally for 3 weeks. NS1 was also administered daily to mice induced high-fat emulsion for 3 weeks. Results: The results showed that in OGTT, NS1 and NS2 inhibit the elevation of plasma glucose level after administering glucose. In mice induced alloxan, plasma glucose level in both NS1 and NS2 was significantly lower than diabetic control and gliclazide group. And NS2 showed more significantly less damage in Langerhans than the other groups. The combination did not showed a better effect than the single use. In mice induced high-fat emulsion, NSI improved the sensitivity of insulin by increasing KITT. Conclusion: The results suggest that NS has an antidiabetic activity by increasing insulin production and improving sensitivity of insulin. The combination NS with gliclazide was probably antagonism

MENINGKATKAN HASIL BELAJAR PESERTA DIDIK DENGAN MODEL PEMBELAJARAN KOOPERATIF TIPE STUDENT TEAM ACHIEVEMENT DIVISION PADA OPERASI HITUNG BILANGAN BULAT DI KELAS IV SDN 1 PAGAR AIR

ABSTRAKBudi, K. Asad. 2018. Meningkatkan Hasil Belajar Peserta Didik Dengan Model Pembelajaran Kooperatif Tipe Student Team Achievement Division Pada Operasi Hitung Bilangan Bulat di Kelas IV SDN 1 Pagar Air. Skripsi, Jurusan Pendidikan Sekolah Dasar, Fakultas Keguruan dan Ilmu Pendidikan, Universitas Syiah Kuala. Pembimbing:(1) Dra. Monawati, M.Pd. (2) Drs. Bakhtiar Hasan, M.Pd.Kata Kunci : hasil belajar dan model pembelajaran kooperatif tipe stadDalam pengoperasian operasi hitung bilangan bulat di kelas IV sebagian besar peserta didik masih mengalami kesulitan. Penelitian ini berupaya mengungkapkan bagaimana tingkat kemampuan guru mengelola pembelajaran, bagaimana aktivitas peserta didik pada proses pembelajaran, dan apakah ada peningkatan hasil belajar peserta didik dengan model pembelajaran kooperatif tipe STAD pada materi operasi hitung bilangan bulat di kelas IV SDN 1 Pagar Air? Secara khusus penelitian ini bertujuan untuk mendeskripsikan tingkat kemampuan guru mengelola pembelajaran, aktivitas peserta didik pada saat pembelajaran, dan peningkatan hasil belajar peserta didik pada materi operasi hitung bilangan bulat melalui model pembelajaran kooperatif tipe STAD.Pendekatan yang digunakan dalam penelitian ini adalah pendekatan kualitatif dalam bentuk Penelitian Tindakan Kelas (PTK), yaitu penelitian yang dilakukan di kelas. Data penelitian ini bersumber dari peserta didik kelas IV-A SDN 1 Pagar Air dengan jumlah 25 peserta didik yang terdiri dari 13 peserta didik laki-laki dan 12 peserta didik perempuan.Teknik pengumpulan data penelitian ini dilaksanakan melalui tes dan observasi. Pemberian tes dilakukan dengan memberikan soal evaluasi disetiap akhir pembelajaran. Pada saat observasi, peneliti bertindak sebagai pengajar dan pelaksanaan observasi dilakukan oleh seorang observer yang merupakan teman sejawat. Pengolahan data dalam penelitian ini adalah: (1) tingkat kemampuan guru mengelola pembelajaran, (2) aktivitas peserta didik, (3) serta ketuntasan hasil belajar.Berdasarkan hasil pengolahan data, temuan penelitian ini dapat dikemukakan sebagai berikut. Tingkat Kemampuan Guru (TKG) Mengelola Pembelajaran pada siklus I, II, dan III yaitu 77,5; 80, dan 80. Persentase Aktivitas Peserta Didik pada siklus I, II, dan III yaitu 81,2%, 88%, dan 91%. Dan nilai rata-rata hasil belajar pada siklus I, II, dan III yaitu 86,7; 70, dan 75,7; dengan ketuntasan belajar klasikal pada siklus I, II, dan III yaitu 79,2%, 83%, dan 87%