RANCANG BANGUN WIRELESS SENSOR NETWORK PERINGATAN DINI LONGSOR BERBASIS MIKROKONTROLER

Intisari — Bencana alam seperti gerakan tanah atau longsor dapat terjadi pada berbagai skala dan kecepatan. Untuk meminimalkan kerugian akibat bencana tersebut maka dilakukan usaha mengenal tanda-tanda yang mengawali gerakan tanah, atau disebut sebagai mitigasi. Penelitian ini dilakukan untuk merancang wireless sensor network yang mampu mengidentifikasi bencana longsor. Node sensor terdiri dari: sensor getaran, sensor kemiringan lahan, sensor pergeseran lahan, kontroler, dan modul transmisi data. Node-node sensor ini ditanam pada daerah yang rawan longsor dan saling berkomunikasi antara node satu dengan lainnya. Data-data berupa getaran, kemiringan lahan, dan status selalu ditransmisikan ke base station sistem peringatan dini longsor secara realtime. Ketika bencana longsor akan segera terjadi node sensor diharapkan mampu mendeteksi dan mengaktifkan alarm yang ada pada node sensor serta mengirimkan tanda bahaya ke base station. Kata Kunci — longsor, wireless sensor network, node sensor, mikrokontroler   Abstrak — Natural disasters such as land movements or landslides can occur at various scales and speeds. To minimize damages due to the disaster, an effort is made to recognize the signs that initiate soil movements or referred to as mitigation. This research was conducted to design a wireless sensor network that can identify landslides. Sensor nodes consist of vibration sensor, slope sensor, land shift sensor, controller, and data transmission module. These sensor nodes are planted in areas inclined to landslides and communicate with each other between nodes. The data vibration, the slope of the land, and status are always transmitted to the base station of the landslide early warning system in real time. When an landslide will occur soon the sensor node is expected to be able to detect and activate the alarm on the sensor node and send an signal to the base station. Keyword — landslides, wireless sensor networks, sensor nodes, microcontroller

ANALISIS PENGARUH PROFIT MARGIN, DER, DPR , ROA DAN FIRM SIZE TERHADAP PBV (Studi Kasus Pada Perusahaan Pertambangan di BEI Periode 2009 -2014)

Company’s value is very important especially for those companies go public because the company's value can be reflected through the stock market price. The higher the price the higher the stock market value of the company. In the long term, the company's goal is to optimize company’s value. Based on previous research, there is research gap between studies in their influence on company’s value and there is declining on performance of the mining company, which made it necessary to assess whether the declining on performance may affect the value of mining companies. The aim of this study was to analyze factors affecting company’s value at a mining company listed on the Indonesia Stock Exchange in 2009-2014. The study population was all financial data of companies listed on the Indonesia Stock Exchange in 2009-2014. The sampling method used in this research is purposive sampling method. The sample used in this study is a mining company listed on the Indonesia Stock Exchange in 2009-2014. The data used is secondary data from Indonesia Stock Exchange. The analysis technique used is multiple linear regression analysis. Based on the results ROA and DER positively influence company’s value while NPM, DPR and firm size does not affect company’s value. Based Adjusted R Square, the coefficient of determination of this study is 0.231, this means that the variations in company’s value can be explained by the independent variable by 23.1%

ANALISIS TRANSFORMASI DAN SPEKTRUM GELOMBANG DI PERAIRAN BALONGAN, INDRAMAYU, JAWA BARAT

Perairan Balongan merupakan salah satu daerah di Indramayu yang strategis. Pemanfaatan wilayah Balongan membutuhkan informasi akurat mengenai karakteristik, penjalaran gelombang, dan spektrum gelombang. Penelitian ini bertujuan untuk mengetahui karakterisitik gelombang, pola transformasi gelombang, dan spektrum gelombang berarah di Perairan Balongan, Indramayu, Jawa Barat. Berdasarkan Hasil Pemodelan diketahui bahwa energi gelombang terbesar terjadi pada Musim Barat yaitu sebesar 0,36 m2/Hz dengan arah distribusi energi dari Timur Laut. Pada Musim Timur penjalaran energi gelombang berasal dari Timur dengan energi maksimum 0,25 m2/Hz. Gelombang pada Musim Peralihan I dan II memiliki arah penjalaran energi gelombang dari Timur. Berdasarkan hasil pemodelan gelombang diketahui bahwa untuk setiap musimnya di Perairan Balongan ketika gelombang menjalar dari perairan dalam ke perairan dangkal mengalami transformasi gelombang. Pada Musim Barat nilai koefisien refraksi yaitu 0,40-0,58 dan koefisien shoaling 0,91-1,1 sedangkan koefisien difraksi pada kolam pelabuhan yaitu 0,74-0,64 dan pada jetty yaitu 0,32-0,54. Pada Musim Peralihan I nilai koefisien refraksi yaitu 0,99-1,00 dan koefisien shoaling 0,92-1,1 sedangkan koefisien difraksi pada kolam pelabuhan yaitu 0,64-0,80 dan pada jetty yaitu 0,63-1.1. Nilai koefisien refraksi pada Musim Timur yaitu 0,99-1,1 dan koefisien shoaling 0,95-1,32 sedangkan koefisien difraksi pada kolam pelabuhan yaitu 0,64-0,72 dan pada jetty yaitu 0,63-1.1. Pada Musim Peralihan II nilai koefisien refraksi yaitu 0,98-1,00 dan koefisien shoaling 0,91-1,1 sedangkan koefisien difraksi pada kolam pelabuhan yaitu 0,79-0,87 dan pada jetty yaitu 0,63-1,10. Kata kunci: Spektrum dan Transformasi Gelombang, ST Wave, Perairan Balonga

ANALISIS DATA EKSTRIM TINGGI GELOMBANG DI PERAIRAN UTARA SEMARANG MENGGUNAKAN GENERALIZED PARETO DISTRIBUTION

Informasi gelombang ekstrim merupakan salah satu faktor yang dipertimbangkan dalam perencanaan bangunan pantai. Tinggi gelombang ekstrim diidentifikasi untuk memaksimalkan ketahanan bangunan pantai terhadap kejadian gelombang tinggi (ekstrim). Penelitian ini mengambil lokasi di perairan utara semarang dimana terjadi berbagai aktivitas pembangunan. Metode Generalized Pareto Distribution digunakan untuk menentukan nilai maksimum yang terjadi (kala ulang) pada periode 2, 5, 10, 25, 50 dan 100 tahun. Pada penelitian ini ambang batas nilai ekstrim ditentukan dengan nilai percentile 90. Berdasarkan hasil uji kesesuaian model menggunakan Uji Kolmogorov- Smirnov disimpulkan bahwa data ekstrim tinggi gelombang di perairan utara semarang mengikuti Generalized Pareto Distribution. Hasil perhitungan kala ulang tinggi gelombang ekstrim tertinggi sebesar 5,73 meter terjadi pada bulan maret dengan periode 100 tahun

The Influence of Coastal Protective Building against Erosion in Sayung Coastal, Demak

In 1980, land conversion of mangrove occur in large numbers since the opening of the Causeway. Flooding and Rob have already begun to be felt since the year 1995 and beginning in 2000 has been sinking a Dukuh village near by Bedono. Year 2000 erosion occurred in district Sayung, Demak and in 2013 the large area known erosion area of 400 – 1300 acres along the coastline. To reduce and overcome the damage done by the shore, re-purposed soft structure (conservation) and hard structure (breakwater). The purpose of this research is to know the influence of the building protective coast against erosion. The method used is the quantitative methods i.e. include survey field and numerical modelling methods. Research results in the form of changes in the rate of erosion in Coastal Sayung Keywords: Coastal, Coastal Building, Erosion, Sediment

The Influence of Madden Julian Oscillation on the Formation of the Hot Event in the Western Equatorial Pacific

Hot event (HE) is the high SST phenomena higher than about 30C, occur in an area of more than 2×106 km2 and last for a period more than 6 days. HE develops only under the condition of high solar radiation and low wind speed. The indication of the relation between HE and MJO has been described in the previous study for one HE case. In the present study, the more case of MJO-HE relation is collected for the period of 2003-2011 and the possible mechanisms is examined. New Generation Sea Surface Temperature for Open Ocean (NGSSTO-Global-V2.0a) was used to identify HEs. Precipitation from TRMM were bandpass filtered with cut off period of 30-60 days for MJO identification. Observation data from TAO/TRITON buoy were used for investigating the possible mechanism of MJO-HE relation. Off 48 HE cases located along the equatorial band, the development of 29 HE cases was related to the suppressed phase of MJO whereas the high solar radiation occurred. High precipitation during the active phase of MJO may contribute to stabilize the upper mixed layer. The stable upper water column fasten the heating process during the suppressed phase of MJO, generating HE

Simulation of Coastal Erosion Model to Support Disaster Mitigation in Coastal Sayung, Demak District

Coastal Sayung, Demak has occurred agricultural land and mangroves conversion for opening the ponds. Land use change inflict 2 small villages sink, namely Tambaksari (1997) and Rejosari (2004). The small villages are damaged by coastal erosion. This coast is an area affected by tides. The study aims to evaluate the erosion in coastal Sayung, by simulation model with mathematic model. The simulation results are calibrated with March and June 2016 bathymetry data. Bathymetry data is obtained by echosounder to acquiring contour depth. Wind data was obtained from NOAA for 10 years. Sediment sampling results indicate the type of silt (72%), clay (24%), and fine sand (4%), with specific gravity 1.51 – 1.85 tons/m3. The data used for hydrodynamics and erosion modeling with mathematic model. The simulation results indicate the greatest erosion value occurs in the transition season I, which is 94,000 m3. Patterns of erosion strongly influenced by the current patterns of a particular season. When the West, current and erosion patterns move towards northeast, and otherwise with the East. The most eroded villages are Sriwulan and Bedono, then Timbulsloko, and the smallest is Surodadi. The results of this study can be used to support disaster mitigation in the coastal Sayung, Demak. Keywords: bathymetry, coastal Sayung, erosion, mathematic model, sedimen

Pengaruh Atribut Produk dan Word of Mouth Terhadap Keputusan Pembelian (Survei pada Konsumen mobil Daihatsu Xenia di Astra Daihatsu Malang)

Penelitian ini bertujuan untuk (1) menjelaskan pengauh atribut produk dan word of mouth secara bersama-sama terhadap keputusan pembelian, (2) pengaruh atribut produk secara parsial terhadap keputusan pembelian, (3) pengaruh word of mouth secara parsial terhadap keputusan pembelian, (4) variabel mana yang berpengaruh dominan terhadap keputusan pembelian. Jenis penelitian yang digunakan adalah explanatory dengan pendekatan kuantitatif. Variabel dalam penelitian ini meliputi Atribut Produk, Word of Mouth dan Keputusan Pembelian. Populasi penelitian ini adalah konsumen mobil Daihatsu Xenia di Astra Daihatsu Malang. Sampel yang digunakan dalam penelitian ini sebanyak 100 responden yang diambil dengan menggunakan purposive sampling dan metode pengumpulan data menggunakan kuesioner. Analisis data yang digunakan adalah analisis deskriptif dan Analisis Inferensial (Regresi Linier Berganda dan Regresi Parsial) Hasil analisis regresi menunjukkan bahwa Atribut Produk (X1) dan Word of Mouth (X2) berpengaruh signifikan secara bersama-sama terhadap keputusan pembelian (Y), Atribut Produk (X1) berpengaruh signifikan secara parsial terhadap keputusan pembelian (Y), Word of Mouth (X2) berpengaruh signifikan secara parsial terhadap keputusan pembelian (Y), Word of Mouth (X2) berpengaruh dominan terhadap Keputusan Pembelian (Y). Berdasarkan hasil penelitian diharapkan pihak Astra Daihatsu dapat mempertahankan kualitas produk dan pelayanan, sehingga keputusan pembelian dapat meningkat

SIMULASI MODEL TRANSPOR SEDIMEN TERSUSPENSI UNTUK MENDUKUNG PERENCANAAN PELABUHAN TELUK BAYUR, SUMATERA BARAT

Simulation model of suspended sediment to support development planning for Teluk Bayur port. The survey was conducted at Teluk Bayur sea waters during September 2008, where this area is development planning for Teluk bayur port. Objective of research is known suspension sediment transport at dredging area and dumping site for development planning of Teluk Bayur port at Teluk Bayur, Province of West Sumetera. Grab sampler was used to carry sediment bottom and Nansen bottle was used collect water sample for total suspended sediment (TSS). Analysis of hydrodynamic pattern used modeling system by software SMS 8.1 (Surface Water Modeling System) with SED2D module. The result had shown that TSS is above sea water standard for marine organism, between 6,0 – 10,0 mg/L. Therefore bottom sediment was dominated by sand, and then silt and gravel. The result of modeling shown that sediment transport depends of monsoon current pattern, where sediment transport to east-northeast on west monsoon and to northwest-north on east monsoon. Dredging and dumping site activity due to decreasing water quality at construction time