Determination of effective diffusion coefficient of immobilized Baker's yeast invertase in various concentration of PVA-alginate matrix

Baker's yeast invertase is immobilized in PVA-alginate matrix using an improved method. PVA beads were prepared by adding calcium alginate to improve its stability, mechanical and chemical properties. Boric acid was used as the cross-linking agent and additional chemicals consisting of 10% boric acid and sodium sulphate solution was used as a treatment solution to harden the PVA-alginate beads. The determination of the effective diffusion of PVA-alginate matrix the vital step in optimizing the preparation of immobilized and water-soluble biocatalyst. In this study the two-level full factorial design was used to investigate the effect of PVA and boric acid concentrations and diffusions coefficient. Diffusion coefficient (De) is one of the factors that significantly affect the mass transport within the immobilization matrix. De value varies for each concentration of PVA and boric acid. The result concluded that both factors significantly affect the De. A maximum De value of 5.0141 x 10(-5) cm2s-1 was obtained at boric acid and PVA concentraion of 7w/v and 10.5 w/v respectively

Regional validation of retracked sea levels from SARAL/Altika over the South China sea and adjacent seas

This paper focuses on assessing the quality of sea level anomaly (SLA) data from the new generation of Ka-band SARAL/AltiKa satellite altimetry over the continental shelf of the South China Sea. The region consists of peninsulas, shallow seas, and small islands that produce complicated altimetric waveform patterns. The improved-accuracy of SLAs data from the MLE4, Ice1 and Ice2 retrackers which are provided in the AVISO-Sensor Geophysical Data Records (SGDR) were optimized in this study. The quality of retracked SLAs is assessed by making comparison with tide gauge data from six stations. In general, the percentage of data availability of Ice-1 retracker is superior ( > 68%) to those of MLE- 4 and Ice-2 retrackers. The improvement of percentage (IMP) also shows that Ice-1 retracker improves the standard deviation > 12% better than those of Ice-2 retracker. Over complex areas of Lubang and Ko Taphao Noi, the temporal correlation of Ice-1 retracker is superior (r > 0.80) to those of MLE4 and Ice-2 retrackers (r 5.8) and lower RMS error ( < 34 cm) than those of Ice-1 retracker. It can be concluded that the Ice-1 and Ice-2 retrackers were superior for the coastal region of Maritime Continent

Nilai Pendidikan Islam dalam Qur'an Surah Luqman Ayat 1-19: Tinjauan Kognitif, Afektif, dan Psikomotorik

The main focuses in this study are 1) Islamic educational values contained in QS Luqman/31: 1-9; 2) fostering cognitive, affective, and psychomotor potential according to QS Luqman/31: 1-9; and 3) the results of the development of cognitive, affective, and psychomotor potential according to QS Luqman/31: 1-9. This study is library research which is descriptive analysis using normative theological, historical, and pedagogical approaches. The results showed that the values of Islamic education in QS Luqman/31: 1-9 included tauhid education, moral education, worship education, social education, mental education, and exemplary education. The application of these educational values in the dimensions of cognitive, affective, and psychomotor is carried out by Luqman al-Hakim who is known to be virtuous, wise, intellectual, and true in words and deeds. The nature and attitude of the educator will produce students who have strong faith, good morals, and understanding of Shari'a by implementing it correctly as evidence of the development of balanced cognitive, affective, and psychomotor potentials

Microstructure development, mechanical and tribological properties of a semisolid A356/xSiCp composite

This paper presents the results of experimental investigation on microstructure (size and morphology of eutectic Si), impact toughness and sliding wear properties of A356 Al-Si alloy and composites containing 10, 20 and 25 wt% of SiCp reinforcement produced by semisolid stirring technique. The results revealed that an increase in SiCp content leads to a reduction in the size of eutectic Si and also changes its morphology from plate-like to equiaxed. Furthermore, addition of 10 and 20 wt% silicon carbide reinforcement decreased the impact toughness by 6 and 18%, respectively. A356/25wt%SiCp composite registered the lowest impact toughness with reduction of 33% due to debonding and agglomeration of SiCp in the matrix. The sliding wear results showed that the wear resistance of the composites was significantly higher than that of the matrix alloy due to the increase in hardness as well as reduction in the size and also morphology transformation of eutectic silicon with increase in SiCp content. However, the existence of particle-porosity clustering with increasing the SiCp content to 25 wt% played a significant role in deteriorating the wear behavior of the composite

Correlation Between Gunung Padang and Sundanese Traditional Roof

Gunung Padang is the oldest prehistoric megaliths in Indonesia which has a function as a place of worship for the people who settled there about 2000BC according to its orientation and philosophy. Meanwhile after dark ages, people knowledge on building shelter arises therefore many traditional houses are build and had their philosophy implemented such as the vertical and horizontal beliefs in relation of human, nature, and divinity. This study concerns architecture identity correlation of place in the two eras because of cultural transition which can be observed until now. Gunung Padang has a similar vertical concept identity compare to Sundanese traditional roof according to both philosophy if the highest place is the most sacred place and describes the relationship between human, nature and divinity. The purpose of this study is to examine the correlation between Gunung Padang and the Sundanese traditional roof concept in religion and cultural aspect. Qualitative methods that leverages vernacular theory is used of the analysis methods

A Novel Method for Rotor Field-Oriented Control of Single-Phase Induction Motor

This paper presents a novel rotor field-oriented control (RFOC) method for asymmetrical single-phase induction motor (SPIM). It is shown in this paper that by using a suitable transformation matrix (TM) for stator current variables, the asymmetrical equations of SPIM are transformed into symmetrical equations. Based on this similarity, a novel vector conrol technique for SPIM is presented. Performance of the proposed method is assessed using MATLAB/SIMULINK software. Simulation results showed the excellence speed and torque responses obtained using the proposed technique

High performance speed control of single-phase induction motors using switching forward and backward EKF strategy

The aim of this research is to provide a high performance vector control of single-phase Induction Motor (IM) drives. It is shown that in the rotating reference frame, the single-phase IM equations can be separated into forward and backward equations with the balanced structure. Based on this, a method for vector control of the single-phase IM, using two modified Rotor Field- Oriented Control (RFOC) algorithms is presented. In order to accommodate forward and backward rotor fluxes in the presented controller, an Extended Kalman Filter (EKF) with two different forward and backward currents that are switched interchangeably (switching forward and backward EKF), is proposed. Simulation results illustrate the effectiveness of the proposed algorithm

Upaya Meningkatkan Hasil Belajar Siswa Pada Materi Jajargenjang Dengan Menggunakan Metode Penemuan Terbimbing Di Kelas IV SDN Inpres Manyula

Penelitian ini bertujuan untuk mendeskripsikan penerapan metode penemuan terbimbing yang dapat meningkatkan hasil belajar siswa Kelas IV SDN Inpres Manyula pada materi jajargenjang. Pengolahan data dalam penelitian ini menggunakan teknik analisis data kualitatif. Data yang dikumpulkan berupa data hasil aktifitas guru dan siswa selama pelaksanaan pembelajaran dengan menggunakan lembar observasi, data hasil wawancara pada setiap siklus dengan beberapa siswa yang dijadikan sebagai informan, dan tes hasil belajar. Penelitian ini adalah penelitian tindakan kelas yang dilaksanakan secara bersiklus. Desain Penelitian ini terdiri dari 4 komponen yaitu perencanaan, tindakan, observasi dan evaluasi/refleksi. Pelaksanaan penelitian tindakan kelas ini mengikuti tahap penelitian tindakan yang tiap tahap disebut siklus. Penelitian ini dilaksanakan dalam dua siklus. Berdasarkan hasil penelitian tampak bahwa hasil belajar siswa meningkat pada materi jajargenjang dengan menggunakan metode penemuan terbimbing pada Kelas IV SDN Inpres Manyula Kecamatan Kintom. Data hasil penelitian menunjukkan bahwa siklus I daya serap klasikal 76,36%, tuntas klasikal 63,64%, hasil observasi aktivitas guru 76,32%, hasil observasi aktivitas siswa 71,05%. Kemudian pada siklus II daya serap klasikal 88,64%, tuntas klasikal 100%, hasil observasi aktivitas guru 90,79%, hasil observasi aktivitas siswa 85,53%. Peningkatan hasil belajar siswa dari siklus I ke siklus II sebesar 16,08%, Peningkatan aktifitas siswa dari siklus I ke siklus II sebesar 20,38% dan aktifitas guru juga mengalami peningkatan dari siklus I ke siklus II sebesar 18,96%