Judul: Electric Vehicle Routing Problem with Soft Time Windows
Abstrak: Masalah perutean kendaraan listrik merupakan perkembangan dari masalah perutean kendaraan konvensional dengan karakteristik unik yang tidak dimiliki kendaraan konvensional. Masalah perutean kendaraan listrik dengan soft time windows memiliki beberapa fitur yang membuat model menjadi lebih fleksibel untuk diimplementasikan. Fitur tersebut antara lainnya adalah tersedianya stasiun pengisian daya kendaraan listrik umum (SPKLU) yang dapat dikunjungi kendaraan sebanyak yang diperlukan serta jumlahnya dapat disesuaikan. Model juga dapat menyesuaikan jumlah dan tipe kendaraan yang digunakan dalam sekali perutean. Tipe kendaraan listrik dapat berupa kendaraan homogen dengan kapasitas muatan dan baterai seragam ataupun heterogen dengan perbedaan kapasitas muatan dan baterai. Terdapat aturan soft time windows yang memberikan fleksibilitas waktu, memungkinkan kendaraan untuk melanggar aturan waktu dengan pemberian biaya penalti. Dalam mengimplementasikan model, tujuh kasus diuji dengan variasi jumlah kendaraan, kapasitas muatan dan baterai kendaraan, jumlah pelanggan dan SPKLU, dan aturan time windows. Penyelesaian masalah ini menggunakan metode eksak menghasilkan solusi optimum yang menciptakan rute perjalanan dengan biaya minimum sesuai dengan aturan soft time windows dan kendala lainnya., The electric vehicle routing problem is a development of vehicle routing problems with unique characteristics not found in conventional vehicles. The electric vehicle routing problem with soft time windows has several features that make the model flexible for implementation. These features include the availability and quantity of charging stations that vehicles can visit as needed can be adjusted. The model can also adapt the number and type of vehicles used in a single routing. Types of electric transport used in this model can be homogeneous with uniform cargo and battery capacity or heterogeneous with different load and battery capacity. There are soft time window rules that provide time flexibility, allowing vehicles to violate time rules with penalty costs. In implementing the model, we used seven cases with variations of number of vehicles, vehicle cargo capacity, vehicle battery capacity, the number of customers and charging stations, and time window rules. Solving this problem using an exact method results in an optimal solution that creates a travel route with minimum costs according to soft time window rules and other constraints.
Keyword: electric vehicle, SPKLU, time windows

Judul: Pengoptimuman Proses Antar Jemput Barang Menggunakan Kendaraan Listrik
Abstrak: Sebuah perusahaan logistik perlu menentukan rute yang optimal untuk meminimalkan biaya operasional dalam pendistribusian produk. Permasalahan pendistribusian ini, khususnya antar jemput barang secara simultan dapat diselesaikan dengan Vehicle Routing Problem with Simultaneous Pickup and Delivery (VRPSPD). Peralihan kendaraan konvensional ke kendaraan listrik merupakan salah satu upaya perusahaan dalam mengurangi gas emisi rumah kaca. Pada penelitian ini akan menyelesaikan permasalahan proses antar jemput barang menggunakan kendaraan listrik yang dimodelkan dengan Electric Vehicle Routing Problem with Simultaneous Pickup and Delivery (EVRPSPD). Kendaraan listrik yang digunakan pada model ini memiliki keterbatasan daya sehingga perlu mengisi daya pada Battery Swapping Station (BSS). Selanjutnya, model akan diimplementasikan pada berbagai macam kasus berbeda yang diselesaikan menggunakan metode eksak dengan bantuan software Lingo 18.0. Hasil yang diperoleh berupa rute distribusi yang optimal dengan meminimumkan jarak serta kendaraan listrik yang mengunjungi BSS untuk pengisian ulang daya., A logistic company needs to determine the optimal route to minimize operational costs in product distribution. This distribution problem, especially the simultaneous pickup and delivery of goods can be solved using the Vehicle Routing Problem with Simultaneous Pickup and Delivery (VRPSPD). The transition from conventional vehicles to electric vehicles is one of efforts carried-out by company in reducing greenhouse gas emission. This research aims to solve the pickup and delivery process problem using electric vehicles, modeled as the Electric Vehicle Routing Problem with Simultaneous Pickup and Delivery (EVRPSPD). The electric vehicles used in this model have limited power and need to recharge at a Battery Swapping Station (BSS). Furthermore, the model will be implemented in various different cases using an exact method with the assistance of Lingo 18.0 software. The results obtained include an optimal distribution route by minimizing the distance traveled and the electric vehicles visiting the BSS for recharging.
Keyword: battery swapping, VRPSPD, electric vehicle, route optimization

Judul: Synthesis of Apatite - Chitosan Composite Using Duck Eggshell and Chitosan with Temperature and pH Control
Abstrak: Composite of apatite-chitosan was prepared by using chitosan as polymer matrix. Calcium phosphate was prepared from CaO and (NH4)2HPO4, which the ratio Ca : P had to be 1.67. Chitosan is produced by deacetilase from biopolymer chitin. Duck eggshell (95% CaCO3) as starting material was converted to be calcium oxide (CaO) through calcinations with temperature 1000oC for 5 hours. In-situ and ex-situ methods were prepared from apatite and chitosan (dissolved with acetate acid 2%). Calcium phosphate prepared for bone implantation, but it is too fragile and brittle to be implant into the body. So addition of chitosan can decrease crystalinity and increase mechanic characteristic (tougher). Composite apatite-chitosan was resulted by fast precipitation. Fast precipitation was held in a breaker glass with nitrogen atmosphere, under controlled temperature at 37oC and pH 7, in order to increase amount of hydroxyapatite. Precipitation with CaO which was dropped by (NH4)2HPO4. Hydroxyapatite and chitosan were appearing at samples with in-situ and ex-situ methods which indicating by peak matching of XRD (closed lattice parameter, crystal size), overlapping at FTIR spectra and supporting by SEM picture (homogenous and agglomerated particle). However, it still needs further research to examine biocompatibility osteoconductive degree of sample by in-vivo and in-vitro test.
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