Pemisahan Krom Pada Limbah Cair Industri Penyamakan Kulit Menggunakan Gelatin Dan Flokulan Anorganik

The aim of the study was to determine the ability of gelatin, ferrous sulfate, aluminium sulfate, and combination of gelatin with ferrous sulfate or aluminium sulfate for total chromium content (trivalent chromium and hexavalent chromium) separation from tannery wastewater. Reduction of total chromium content in the wastewater was conducted using combination of gelatin and ferrous sulfate or gelatin and aluminium sulfate with a ratio of 4:0; 3:1; 2:2; 1:3; and 0:4 (w/w). The results showed that gelatin, ferrous sulfate, and aluminium sulfate, were able to reduce total chromium content in the wastewater. Combination of gelatin/ferrous sulfate or gelatin/aluminium sulfate as flocculants provide synergistic work in reducing the total chromium content. A 94.75% removal of total chromium content was achieved by combining gelatine and aluminium sulfate with a ratio of 3:1, clearer wastewater, and followed by reduction of degree of turbidity up to 74.47%. The total chromium content after treatment was 0.61 ppm, which met the requirements of wastewater for business and or daily activities especially for tanning industry

Pemanfaatan Trimming Kulit Pikel Sebagai Flokulan Melalui Hidrolisis Kolagen Menggunakan Basa Untuk Penjernihan Air

Wastes in the form of skin derivatives from leather tanning industries remain serious problems if not managed properly and quickly, since they can cause environmental pollution. This research aimed at studying the influence of base type and concentration for the hydrolysis of trimmed collagen from pickled sheepskin to the yield and properties of gelatin, as well as the gelatin's potential as flocculant. The hydrolysis of trimmed collagen from pickled sheepskin was performed using KOH or NaOH solution, each with varied concentrations of 1, 2, 3, and 4% w/v, for 16 hours. The extraction of the resulting gelatin was performed using water (2.5 water part : 1 waste part), at 70-80 oC, for 3 hours. The results show that the yield of gelatin from hydrolysis using KOH (16.50-28.60%) is lower than that using NaOH (23.68-34.42%). The water and fat contents of the resulting gelatin were relatively similar, while the protein content from KOH treatment was higher than that from NaOH treatment. Hydrolysis with KOH 1% and NaOH 1% and 2% resulted in gelatin that can be used as flocculant. Hydrolysis with NaOH 2% was the best treatment to produce gelatin as flocculant

A Cognitive Radio Spectrum Sensing Algorithm to Improve Energy Detection at Low SNR

Energy detection is among the most popular spectrum sensing method for spectrum sensing due its low complexity. Unfortunately, its performance is poor at low SNR. In this paper we proposed a spectrum sensing method for cognitive radio network that improves the performance of energy detection. The proposed method based on distribution analysis using kurtosis as test statistic. This comes from the fact that distribution of received signal when a channel is occupied will be different from vacant channel. Noise tends to have a Gaussian distribution. Signal which faces multipath fading during the transmission way will have non Gaussian distribution. Sensing algorithm was tested using captured DTV signal. Result shows that our method performs well at low SNR. It achieves probability of detection of 90 % for 10 % Probability of false alarm for low SNR, below -20 dB

Sifat Fisika Dan Morfologi Nanokomposit ABS/PC Dengan Filler Nano Precipitated Calcium Carbonate (NPCC)

The purpose of this research was to study the effect of blend ratios of acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) in the different amount of nanoprecipitated calcium carbonate (NPCC) on the physical properties of ABS/PC nanocomposites. Nanocomposites were prepared in varied ratio of ABS/PC 100/0; 90/10; 80/20; 70/30 and varied amount of NPCC 0; 2.5; and 5 phr (per hundred resin), Nanocomposites were made by melt compounding in the Laboplastomill internal mixer at 200°C for 10 minutes. The SEM micrographs showed homogeneous dispersion of the nanocomposite materials and did not show aglomeration of NPCC. The best nanocomposite was a nanocomposite containing the ABS/PC 90/10 with NPCC 2.5 phr perfomed with impact resistance 5030 J/m2, tensile strength 380.14 kg/cm2, elongation at break 3.59%, density 1.16 g/cm3, and hardness 85 Shore D

Detektor Ml Untuk Komunikasi Antena Jamak

Simple ML Detector for Multiple Antennas Communication System. In order to support providing broadbandwireless communication services against limited and expensive frequency bandwidth, we have to develop a bandwidthefficient system. Therefore, in this paper we propose a closed-loop MIMO (Multiple-Input-Multiple-Output) systemusing ML (Maximum Likelihood) detector to optimize capacity and to increase system performance. What is especiallyexciting about the benefits offered by MIMO is that a high capacity and performance can be attained without additionalfrequency-spectral resource. The grand scenario of this concept is the attained advantages of transformation matriceshaving capability to allocate transmitted signals power suit to the channel. Furthermore, product of these matrices formsparallel singular channels. Due to zero inter-channels correlation, thus we can design ML detector to increase thesystem performance. Finally, computer simulations validates that at 0 dB SNR our system can reach optimal capacityup to 1 bps/Hz and SER up to 0.2 higher than opened-loop MIMO

Model Sinusoida Secara Segmental Untuk Pengkodean Sinyal Suara

Segmental Sinusoidal Model for Speech Signal Coding. Periodic signal can be decomposed by sinusoidal componentwith Fourier series. With this characteristic, it can be modeled referring by sinusoidal form. By the sinusoidal model,signal can be quantized in order to encode the speech signal at the lower rate. The recent sinusoidal method isimplemented in speech coding. By using this method, a block of the speech signal with 20 ms to 30 ms width is codedbased on Fourier series coefficients. The new method proposed is quantization and reconstruction of speech signal bythe segmental sinusoidal model. A segment is defined as a block of the speech signal from certain peak to consecutivepeak. The length of the segment is variable, instead of the fixed block like the recent sinusoidal method. Coder consistsof the encoder and the decoder. Encoder works to code speech signal at variable rate. Then coded signal will betransmitted to receiver. On the receiver, coded signal will be reconstructed, so that the reconstruction signal has the nearquality compared with the original signal. The experimental results show that the average of segmental SNR is morethan 20 dB

PEMAHAN TERHADAP MENOPAUSE HUBUNGANNYA DENGAN TINGKAT KECEMASAN PADA lBU-lBU DI KABUPATEN SLEMAN, DAERAH ISTlHEWA YOGYAKARTA

Tujuan penelitian ini untuk mengetahui pemahaman terhadap menopause, tingkat kecemasan serta hubungan antara pemahaman terhadap menopause dengan tingkat kecemasan menghadapi menopause pada ibu-ibu di Kabupaten Sleman, Daerah Istimewa Yogyakarta. Populasi penelitian ini adalah ibu-ibu yang mas1h terikat dalam perkawinan atau yang masih bersuami yang berusia antara 40 - 61 tahun baik yang masih menstruasi maupun yang sudah menopause. Pemilihan sampel dilakukan dengan Multistage area random sampling. Mula-mula dar1 17 Kecamatan yang ada di Kabupaten Sleman, diambil 4 Kecamatan secara acak, kemudian dari masing-mas1ng kecamatan diambil satu desa secara acak pula, dan ditemukan4 desa dari 4 kecamatan yaitu: 1). Desa Caturtunggal, Kecamatan Depok. 2). Desa Sinduadi, Kecamatan Ngaglik. 3). Desa Wedomartani, Kecamatan Ngemplak dan 4). Desa Sido Agung, Kecamatan Godean. Pengumpulan data dilakukan dengan angket yaitu angket tentang pemahaman terhadap menopause yang disusun sendiri oleh tim peneliti, sedang tingkat kecemasan menggunakan kuestioner yang dikembangkan oleh Janet A. Taylor yang disebut dengan Taylor Manifest Anxiety Scale (T. MAS), untuk mengungkap kecemasan yang berkaitan dengan menopause. Uji kesahihan butir untuk instrumen pemahaman dengan analisis butir, sedang rel1abilitasnya dengan teknik Alpha dari Cronbach. Instrumen kecemasan sudah teruji keandalannya (Yulia, 1990) dengan hasil 0,897 dengan p = 0,01. Uji validitasnya dengan analisis butir. Teknik analisis yang digunakan adalah statistik deskriptif, sedangkan untuk menguji hipotesis dilakukan dengan analisis korelasi momen tangkar. Hasil penelitianmenunjukkanbahwa : 1) Tingkat pemahaman terhadap menopausepada ibu-ibu di Kabupaten Sleman tergolong rendah. 2). Tingkat kecemasan dalam menghadapi menopause juga tergolong rendah. 3) Tidak ada hubungan antara pemahaman terhadap menopause dengan tingkat kecemasan menghadapi menopause pada ibu-ibu di Kabupaten Sleman