Sebelas Maret University

About: Sebelas Maret University is a education organization based out in Surakarta, Indonesia. It is known for research contribution in the topics: Population & Public health. The organization has 10901 authors who have published 10832 publications receiving 33057 citations. The organization is also known as: Universitas Negeri Surakarta & Universitas Sebelas Maret.

Expropriation by the controlling shareholders on firm value in the context of Indonesia: corporate governance as moderating variable

Abstract: This research discusses the influence of cash flow right, control right and cash flow right leverage on firm value. This research also discusses the influence of corporate governance as moderating variables of cash flow right leverage on firm value. The research has 83 public corporations as research sample. All of the firms kept on the list during observation period that is from 2007-2010. The result of statistical test indicates that cash flow right is the dominant variable influencing firm value. The result shows that cash flow right has a positive effect on firm value, indicating that firm value increases as cash flow right of the controlling shareholder increases. Other variables are inconsistent when tested by using moderating variable or by adding control variables.

Improved multiple secret sharing using generalized chaotic image scrambling

Abstract: This paper presents a new technique on (n, n)-Multiple Secret Sharing (MSS) of color images. In this task, n shared images are generated from n secret images, while n recovered secret images can be reconstructed from n shared images. The proposed method employs the Chinese Remainder Theorem (CRT) and bitwise eXclusive-OR (XOR) operation for generating a set of shared image from a set of secret images. The proposed method improves the security level of (n, n)- MSS scheme by developing and utilizing the generalized chaotic image scrambling. This image scrambling effectively overcomes the problem on former existing MSS scheme while the number of secret images is odd number. As documented in experimental section, the proposed method offers a good result on (n, n)- MSS task. At the same time, the proposed method outperforms the former exising schemes in the MSS field.

Penerapan Model Problem Based Learning (Pbl) Pada Pembelajaran Hukum - Hukum Dasar Kimia Ditinjau Dari Aktivitas Dan Hasil Belajar Siswa Kelas X IPA SMA Negeri 2 Surakarta Tahun Pelajaran 2013/2014

Abstract: Telah dilakukan penelitian yang bertujuan untuk mengetahui aktivitas belajar ( visual, oral, writing, listening, mental, dan emotional ) dan hasil belajar (sikap, keterampilan, dan pengetahuan) siswa pada materi hukum-hukum dasar kimia dengan menerapkan model pembelajaran PBL yang dilengkapi LKS pada pelaksanaan Kurikulum 2013. Penelitian ini merupakan penelitian deskriptif kualitatif yang terdiri atas tahap orientasi, eksplorasi, dan member check . Subyek penelitian diambil dengan teknik purposive sampling yaitu siswa kelas X IPA 3 SMA Negeri 2 Surakarta tahun pelajaran 2013/2014 yang berjumlah 32 siswa. Sumber data berasal dari guru dan siswa. Data penelitian dikumpulkan melalui metode wawancara, observasi, angket, dokumentasi/arsip, dan tes. Teknik pengumpulan data dilakukan dengan tes (ranah pengetahuan) dan non tes (angket sikap dan aktivitas belajar). Berdasarkan hasil penelitian menunjukkan bahwa: 1) Proses belajar yang ditinjau dari aktivitas siswa ( visual, oral, writing, listening, mental, dan emotional ) dengan model PBL dilengkapi dengan LKS dalam penerapan kurikulum 2013 dikategorikan baik dengan dengan rata-rata 82,71 dan persentase ketercapaian sebesar 81,25%, 2) Hasil belajar siswa pada ranah pengetahuan, sikap, dan keterampilan siswa dengan model PBL dilengkapi dengan LKS dalam penerapan kurikulum 2013 dikategorikan baik dengan rata-rata nilai berturut-turut adalah 81; 83; dan 79, dan 3) Hasil belajar siswa pada ranah pengetahuan, sikap, dan keterampilan siswa dengan model PBL dilengkapi dengan LKS dikategorikan baik dengan persentase siswa yang mencapai kompetensi inti kurikulum 2013 berturut-turut adalah 78%, 81,24% dan 78,13%. Kata Kunci : deskriptif kualitatif, problem based learning (PBL), aktivitas belajar, hasil belajar

Fabrication and viscoelastic characteristics of waste tire rubber based magnetorheological elastomer

Abstract: In this study, waste tire rubber (WTR) was successfully converted into magnetorheological (MR) elastomer via high-pressure and high-temperature reclamation. The physical and rheological properties of WTR based MR elastomers were assessed for performance. The revulcanization process was at the absence of magnetic fields. Thus, the magnetizable particles were allowed to distribute randomly. To confirm the particle dispersion in the MR elastomer matrix, an observation by scanning electron microscopy was used. The magnetization saturation and other magnetic properties were obtained through vibrating sample magnetometer. Rheological properties including MR effect were examined under oscillatory loadings in the absence and presence of magnetic fields using rotational rheometer. The WTR based MR elastomer exhibited tunable intrinsic properties under presentation of magnetic fields. The storage and loss modulus, along with the loss factor, changed with increases in frequency and during magnetization. Interestingly, a Payne effect phenomenon was seen in all samples during dynamic swept strain testing. The Payne effect was significantly increased with incremental increases in the magnetic field. This phenomenon was interpreted as the process of formation–destruction–reformation undergone by the internal network chains in the MR elastomers.