Pengaruh Gelombang Pada Profil Kemiringan Pantai Pasir Buatan (Uji Model Fisik Dan Studi Kasus Penanggulangan Erosi Serta Pendukung Konservasi Lingkungan Daerah Pantai)

Masalah utama di daerah pantai adalah erosi pantai yang terjadi akibat gempuran gelombang serta pembangunan konstruksi yang tidak akrab lingkungan. Salah satu USAha pengembangan daerah pantai yang sedang dan telah dilaksanakan adalah pembangunan pantai buatan (artificial beach nourishment). Pada tulisan ini disajikan hasil penelitian yang bertujuan untuk mengetahui pengaruh karakteristik gelombang (tinggi gelombang H, periode gelombang T dan panjang gelombang L) terhadap Equilibrium Beach Profile (EBP) atau final slope (nf) (profil) yang terbentuk terutama pada area swash zones.Uji model fisik 3-D dilakukan terhadap material penyusun pantai berupa pasir (d50 = 0,467 - 1,2 mm), dengan bangunan pelindung berupa gabungan groin I dan L. Model pantai pasir di tempatkan pada kolam gelombang, dengan initial slope (n = 6) dan dikenai gelombang reguler konstan hingga kondisi EBP tercapai. Untuk setiap model uji dilakukan variasi tinggi gelombang (H) dan periode gelombang (T).Hasil penelitian menunjukkan EBP atau profil kemiringan stabil yang terbentuk dipengaruhi oleh karakteristik gelombang. Pada area terbuka, semakin besar H0/L0, profil yang terbentuk akan bergeser dari swell profile menjadi storm profile, yang ditunjukkan oleh terjadinya bar. Jika H0/L0 semakin besar, pantai akan semakin tegak (nilai nf semakin kecil), hal ini identik dengan hasil penelitian 2 D dan studi kasus di pantai Sanur, Bali yang dilakukan Setyandito dkk. (2010) serta kajian teoritis dari penelitian sebelumnya. Landai akhir, nf yang terbentuk pada area terbuka pada hasil penelitian ini memiliki nilai 3 hingga 12

An efficient sonochemical oxidation of benzyl alcohols into benzaldehydes by FeCl3/HNO3 in acetone

Sonochemical oxidation of benzyl alcohols into corresponding aldehydes by FeCl3/HNO3 in acetone at room temperature has been reported. All substrates give good yield of the products within 10-25 min. The reaction of selected substrates were also studied under reflux and at the room temperature. Further, various Lewis acids were used to evaluate their catalytic efficacy. © 2011 Elsevier B.V. All rights reserved

Privacy Risk of Personal Information Exposure

Customers’ individual private information are collected to gain valuable information. Through business analytics companies gain competitive advantage in making decisions. However, some irresponsible companies sell customer’s data to third party for illegal activities. This caused distrust and lack of confidence among consumers in revealing their private information. Due to customer reluctant in disclosing their information, this may hinder the growth of e-commerce. Therefore, the purpose of this study is to investigate consumer sensitivity towards data privacy. This research adopted a research framework based on ‘Concern for Information Privacy’ (CFIP) dimensions to further conducted the study. This study has tested relationship using five independent variables. A total number 384 data were collected from respondents using questionnaire. Regression was employed to analyse the relationship between identified variables. Result found that collection, unauthorized secondary internal use, unauthorized secondary external use, improper access and errors have a positive influence on consumer sensitivity towards data privacy. Furthermore, the effects of unauthorized secondary internal use on consumer sensitivity towards data privacy is found to be significantly greater

Measurement of long shore current after permeable groin by floating object

Measurement of long shore current before and after permeable groin structure installation is difficult especially in hydraulic model of small water depth. The problems arise that no instrument is dedicated to measure such current at very small depth and long shore current varies quite significantly from the location of breaking wave to the\ud maximum run up position. Measuring instruments that can be used to measure the long shore currents on a laboratory scale is very limited. Measurement of long shore current using floating objects is a method to overcome the limitations of measuring instruments of longs shore current. Floating objects arranged width surf zone and then was dropped by observing the position of the wave. Then the movement of floating objects was recorded by using a video camera. The magnitude of long shore current velocity obtained from the observation of movement distance of floating objects per\ud time unit. The results of measurements of long shore current by floating objects was verified by the results of calculations using the equations of long shore current (equation Longuet-Higgins, 1970). Verification of the measurement results with the results of calculations indicate relatively similar results, so the floating objects method can be recommended for the measurement of long shore current

Factors affecting the low achievement of utilization efficiency of wave energy for electric power plant with tapered channel technology

Ocean waves is one of the alternative sources of renewable energy that widely available on earth.\ud Attempt on conversion of wave energy into electric power has a lot to do, but it is still constrained by the low\ud achievement of utilization efficiency. This paper presents the results of physical model research regarding the factors\ud affecting the efficiency achievement of the design of Baron Wave Power Plant with Tapered Channel (Tapchan)\ud technology. The model investigation was conducted on 15 m x 20 m size of three dimensional wave basins in The\ud Applied Hydraulics Laboratory Department of Civil and Environmental Engineering Gadjah Mada University. Tapchan\ud model was built based on the design drawings and field data survey in the geometric scale of 1:25. The models were\ud simulated with 3 kinds of wave direction (175o; 191o and 210o) where the designed center line of tapered channel at the\ud direction of 178o. Nine variations of wave height and period in 3 kinds of water depth (LWL, MSL, and HWL) were\ud used to simulate the models. The results indicate that the low performance efficiency was only about 1% -14% or an\ud average of 7% and much influenced by main factors, namely the collector wall geometric, the alignment of channel\ud direction with the incoming wave direction and the magnitude of wave deformations at the bay

Uptake of divalent metal ions (Cu2+, Zn2+, and Cd2+) by polysiloxane immobilized diamine ligand system

Porous solid siloxane polymers carrying diamine functional group of formula P–(CH2)3NH–CH2CH2NH2 (where P–represents a silica-like siloxane framework) have been prepared by replacement of the iodine in iodopolysiloxane with ethylenediamine. The iodofunctionalized polysiloxane was prepared by polycondensation of Si(OEt)4 and (MeO)3Si(CH2)I. The polysiloxane diamine ligand system exhibits high potential for preconcentration of divalent metal ions (Cu2+, Zn2+, and Cd2+). The tendency to chemisorb these divalent metal ions by the diamine ligand system at the optimum conditions was found in the order: Cu2+ > Zn2+ > Cd2+. Diamine ligand system suffers from leaching of ligand containing groups upon treatment with acidic solutions