The activated torsion oscillation magnetometer

The activated torsion oscillation magnetometer exploits the mechanical resonance of a cantilever beam, driven by the torque exerted on the sample by an ac field applied perpendicularly to the film plane. We describe a model for the cantilever dynamics which leads to the calculation of the cantilever dynamic profile and allows the mechanical sensitivity of the instrument to be expressed in terms of the minimum electronically detectable displacement. We have developed a capacitance detector of small oscillations which is able to detect displacements of the order of 0.1 nm. We show that sensitivities of the order of 0.5(10-11 Am2 can be in principle achieved. We will subsequently describe the main features of the ATOM prototype which we have built and tested, with particular attention to the design solutions which have been adopted in order to reduce the effects of parasitic vibrations due either to acoustic noise, originating from the ac field coil, or to eddy currents in the capacitor electrodes. The instrument is mounted in a continuous flow cryostat and can work in the 4.2-300 K temperature range. Finally, we will show that our experimental set-up has a second mode of operation, named Torsion Induction Magnetometer (TIM).Comment: Invited Talk at the Moscow International Symposium on Magnetism, 2002 to appear in the J. Mag. Mag. Mat Revised versio

Prototype Media Sosial Pertanian di Indonesia untuk Perangkat Bergerak Berbasis Android

Meskipun terkenal sebagai negara agraris, kebutuhan pokok masyarakat Indonesia masih tergantung pada negara asing. Produksi pertanian Indonesia tidak mengalami peningkatan, bahkan cenderung menurun. Salah satu penyebabnya adalah kurangnya pengetahuan petani dan tidak adanya komunikasi atas kebijakan yang telah dibuat pemerintah kepada penggerak pertanian. Penelitian ini bertujuan untuk merancang aplikasi media sosial bidang pertanian di Indonesia yang disebut dengan ASMI (Agriculture Social Media Indonesia). Perancangan prototype menggunakan metode Mobile Development Life Cycle (MDLC) dengan tahapan identifikasi, perancangan, pembangunan, prototype, pengujian,dan perawatan. Hasil penelitian menunjukkan prototype ASMI dapat digunakan untuk melengkapi kebutuhan informasi dan komunikasi bidang pertanian. Prototype ASMI dapat digunakan oleh masyarakat, petani, pemerintah, pemerhati pertanian, peneliti, dosen, dan pakar sebagai media komunikasi bidang pertanian

Theory for nucleation at an interface and magnetization reversal of a two-layer nanowire

Nucleation at the interface between two adjoining regions with dissimilar physical properties is investigated using a model for magnetization reversal of a two-layer ferromagnetic nanowire. Each layer of the nanowire is considered to have a different degree of magnetic anisotropy, representing a hard magnetic layer exchange-coupled to a softer layer. A magnetic field applied along the easy axis causes the softer layer to reverse, forming a domain wall close to the interface. For small applied fields this state is metastable and complete reversal of the nanowire takes place via activation over a barrier. A reversal mechanism involving nucleation at an interface is proposed, whereby a domain wall changes in width as it passes from the soft layer to the hard layer during activation. Langer’s statistical theory for the decay of a metastable state is used to derive rates of magnetization reversal, and simple formulas are found in limiting cases for the activation energy, rate of reversal, and critical field at which the metastable state becomes unstable. These formulas depend on the anisotropy difference between each layer, and the behavior of the reversal rate prefactor is interpreted in terms of activation entropy and domain-wall dynamics

Kemampuan Pragmatik Mahasiswa Tingkat II Jurusan Bahasa Prancis, Fbs-unj

The objective of this study is to find out the information about pragmatics competence of second year student in the French Department, State University of Jakarta (UNJ) Jakarta. The writers believed that it is important to conduct this study, because pragmatics competence actually is not taught explicitly in the French Department. Meanwhile, pragmatics competence plays an important role both in oral and written communication. It is hope that this study can give the contribution to the French Department especially to French curriculum department. This study was conducted on July in 2007 in the French Department, UNJ Jakarta. It was conducted through descriptive analytical interpretative by analysing the result of students' pragmatics competence test. The population of this study is 35 French students of UNJ Jakarta who have completely taken all language skills subject. The instrument of this study is the test of pragmatics competence, which consists of 40 questions in form of multiple choices. The process of pragmatics test designing was based on the themes that have been learnt during learning process. In the French Department, pragmatics is not taught explicitly but it is integrated in the language skills subject such as writing, reading, speaking and listening. The data showed that there are 10 questions which cannot be answered correctly by the students. It is because the number of errors done by the students ranges from 18 to 30. In contrast, there are 20 questions which can be answered correctly by the students. It is because the number of errors done by the students ranges from 1 to 8. The result of this study showed that the students already have a good understanding of pragmatics which is practically integrated in the language skills subject. In addition, student's pragmatics competence relates thoroughly to his/her creativity. To summarize, if the student is creative, he/she will then be able to use the language relevant to the context occurred, or in other words, he/she understands well the pragmatics. It is therefore important for the teachers to develop students' pragmatics competence by exposing them to practicing the language in various setting

Barium alginate capsules for 3D immobilisation of living cells: morphology, membrane properties and permeability

Encapsulation in a barium alginate membrane is a promising strategy to obtain a three dimensional culture of living cells: membrane properties are crucial for a realistic clinical application. A one-step encapsulation technique, recently developed for controlled release of boar semen, was employed to prepare barium alginate and protamine-alginate membranes: permeability to two model molecules (haemoglobin and glucose) was evaluated. Capsules were evaluated for technological properties and scanning electron microscopy was used to examine the external morphology of the capsules and the 3D distribution of the cells within the core. The results indicate that 3D arrangement and cell shape are maintained, capsule dimensions and mechanical properties can be modulated, as well as their permeability to model molecules such as haemoglobin and glucose

Strategi Quantum Learning Dalam Upaya Meningkatkan Kemampuan Berbicara Siswa (Penelitian Tindakan Kelas terhadap Siswa Kelas VIII F SMPN 1 Karangtengah Kab. Garut).

Tujuan yang hendak dicapai dalam penelitian ini adalah untuk mengetahui kemampuan berbicara siswa dengan penerapan strategi quantum learning pada pembelajaran melakukan wawancara dengan narasumber pada siswa kelas VIII F SMPN 1 Karangtengah Kab. Garut. Penelitian ini merupakan penelitian tindakan kelas (PTK) yang dilakukan di SMP Negeri 1 Karangtengah dengan subjek siswa kelas VIII F yang berjumlah 30 siswa. Adapun yang menjadi objek penelitian adalah pembelajaran berbicara yang termasuk dalam mata pelajaran Bahasa Indonesia. Proses penelitian ini dilaksanakan dalam dua siklus yang masing-masing siklus meliputi empat tahap, yaitu tahap perencanaan, tahap pelaksanaan, tahap observasi, serta tahap evaluasi dan refleksi. Tahap perencanaan tindakan meliputi (1) membuat skenario pembelajaran, (2) mempersiapkan sarana pembelajaran, (3) mempersiapkan instrumen penilaian, dan (4) mengajukan solusi alternatif berupa penerapan strategi quantum learning dalam pembelajaran berbicara. Pada tahap pelaksanaan peneliti mengadakan pengamatan terhadap tindakan yang telah dilakukan dapat mengatasi masalah yang ada. Selain itu, pengamatan dilakukan untuk mengumpulkan data yang nantinya diolah untuk menentukan tindakan yang akan dilakukan selanjutnya. Tahap observasi dilakukan peneliti dengan mengamati dan menginterpretasikan penerapan strategi quantum learning dalam pembelajaran keterampilan berbicara serta mengolah data untuk mengetahui ada tidaknya peningkatan kualitas proses dan hasil pembelajaran berbicara siswa dengan strategi quantum learning tersebut, juga untuk mengetahui kelemahan yang mungkin muncul. Tahap evaluasi dan refleksi dilakukan peneliti dengan menganalisis atau mengolah data hasil observasi dan interpretasi sehingga diperoleh kesimpulan bagian yang perlu diperbaiki dan bagian mana yang sudah mencapai tujuan penelitian. Berdasarkan hasil penelitian dapat disimpulkan terdapat peningkatan kualitas pembelajaran keterampilan berbicara, yang meliputi (1) peningkatan kualitas proses pembelajaran keterampilan berbicara tersebut ditandai dengan meningkatnya (a) jumlah siswa yang aktif dalam mengikuti pembelajaran berbicara, (b) jumlah siswa yang berani berbicara di depan kelas, dan (c) jumlah siswa yang melakukan kerjasama dengan pasangannya, (2) Peningkatan kualitas hasil pembelajaran ditandai dengan meningkatnya jumlah siswa yang mencapai batas ketuntasan dalam keterampilan berbicara dengan rata-rata ketuntasan mencapai KKM 70 dan persentase ketuntasan 75%. (3) berdasar hasi analisis, yaitu: (a) pada siklus I sebanyak 53% atau 16 siswa dengan rata-rata ketuntasan 68, (b) pada siklus II sebanyak 77% atau 23 siswa dengan rata-rata ketuntasan 71 sehingga penggunaan strategi quantum learning dapat meningkatkan kualitas hasil pembelajaran keterampilan berbicara pada siswa

Hubungan Pola Asuh Orangtua Dengan Perkembangan Emosi Anak Usia PRA Sekolah Di Tk Rohmatul Magfiroh Desa Pakisaji Kecamatan Pakisaji Kabupaten Malang

Anak usia pra sekolah (4-6 tahun) perlu mendapatkan stimulus dan pola asuh yang positif untuk mengembangkankan fungsi motorik, kognitif dan afeksi. Bentuk perkembangan afeksi adalah perkembangan emosi negatif dan positif yang diakibatkan dari pemberian pola asuh orangtua (authoritarian, permissive, authoritative). Tujuan penelitian ini untuk melihat hubungan antara pola asuh orangtua dengan perkembangan emosi anak usia pra sekolah. Desain penelitian yang digunakan adalah observational analitik dengan pendekatan cross sectional studi. Sampel dipilih dengan menggunakan total sampling berjumlah 49 orangtua (ibu) anak usia pra sekolah dan 49 anak usia pra sekolah di TK Rohmatul Magfiroh Desa Pakisaji Kecamatan Pakisaji Kabupaten Malang. Hasil penelitian ini menunjukkan 35 (71,4%) orangtua (ibu) anak usia pra sekolah menerapkan pola asuh demokratis dan 36 (73,5%) anak memiliki perkembangan emosi positif. Uji statistik Chi Square penelitian ini menunjukkan hubungan pola asuh orangtua dengan perkembangan emosi anak usia pra sekolah, dengan nilai  hitung ≥ tabel (9,698 > 5,991)  dan memiliki nilai p < 0,05 (0,008 < 0,05). Hasil penelitian ini dapat digunakan sebagai rekomendasi untuk penelitian selanjutnya mengenai pengaruh budaya terhadap perkembangan emosi

Evaluasi Kelayakan Finansial Usaha Peternakan Dan Pengembangan Biogas: Studi Kasus Desa Suntenjaya, Bandung

This study aims to evaluate the feasibility of biogas project in Suntenjaya Village, Bandung and identify factors that affect revenues, environment and wider economic benefit of the project, using benefit cost analysis, multiple regression, and descriptive analysis. The results show that biogas project is feasible to be developed. Variables that significantly influence on the biogas project are total amount of poultry's waste, total amount of water, and labor. Economic impact of biogas from employment is 1.96%. Furthermore, fuel cost savings of biogas is IDR1,406,160. Environmental impact shows that mostly of cow farmer agree that biogas development project give positive impacts to environment