MODIFICATION OF CROSSOVER OPERATOR ON GA APPLICATION FOR TSP

Genetic Algorithm (GA) has been widely used in many fields of optimization; one of them is Traveling Salesman Problem (TSP). GA in the TSP is primarily used in cases involving a lot of vertices, which is not possible to enumerate the shortest route. One of stages in GA is crossover operation to generate offspring’s chromosome based on parent’s. Example of some crossover operators in GA for TSP are Partially Mapped Crossover (PMX), Order Crossover (OX), Cycle Crossover (CX), and some others. However on constructing the route, they are not considering length of the route to maximize its fitness. The use of random numbers on constructing the route likely produces offspring (a new route) that is not better than its parent. Sequence of nodes in the route affects the length of the route. To minimize uncertainty, then the crossover operation should consider a method to arrange the chromosomes. This article studied incorporating two methods into crossover stage, in order to ensure the offspring has good fitness. Methods to be combined with algorithms are commonly used in the route searching; those are Nearest Neighbor algorithm, and Sequential Insertion. Operators used are CSI (Crossover combined with Sequential Insertion) and CNN (Crossover combined with Nearest Neighbor), named after the method used. Those operators are compared with PMX operator on test using benchmark data from TSPLIB on some independent executions. The tests showed that CSI are better than two other and length of its route was relatively equal to optimal length recorded. Keywords: Genetic Algorithm, Traveling Salesman Problem, Crossover operato

THE CHARACTERISTICS STUDY OF SOLVING VARIANTS OF VEHICLE ROUTING PROBLEM AND ITS APPLICATION ON DISTRIBUTION PROBLEM

Vehicle Routing Problem (VRP) is one of the most challenging problems in combinatorial optimization. Objective of VRP is to find minimum length route starts and ends in a depot. There are some additional constraints such as more than one depot, service time, time window, capacity of vehicle, and many more. These are cause of VRP variants. Vehicle Routing Problem with Time Windows (VRPTW) is a variant of VRP with some additional constrains, that are number of requests may not exceed the vehicle capacity, as well as travel time and service time may not exceed the time window. Multi Depot Vehicle Routing Problem (MDVRP) has number of depots serving all customers, a number of vehicles distributing goods to customers with a minimum distance of distribution route without exceeding the capacity of the vehicle. Many researches have presented algorithms to solve VRPTW and MDVRP. This article discusses solution characteristics of VRPTW and MDVRP algorithms, and their performance. VRPTW algorithms reviewed are Tabu Search, Clarke and Wright, Nearest Insertion Heuristics, Harmony Search, Simulated Annealing, and Improved Ant Colony System algorithm. Performance of MDVRP algorithms studied are Self-developed Algorithm, Upper Bound, Clarke and Wright, Ant Colony Optimization, and Genetic Algorithm. Each algorithm is studied on its performance, process, advantages, and disadvantages. This article presents example of distribution problem in VRPTW and MDVRP, based on characteristic of the real problem. A computer program created using Delphi is implemented for VRPTW and MDVRP, to solve distribution problem for any number of vehicles and customer locations. Keywords: VRPTW, MDVRP, Distribution proble

ALGORITMA VARIABLE NEIGHBORHOOD DESCENT (VND) PADA VEHICLE ROUTING PROBLEM WITH SIMULTANEOUS DELIVERY AND PICKUP (VRPSDP) DAN IMPLEMENTASINYA

Vehicle Routing Problem with Simultaneous Delivery and Pickup (VRPSDP) is a variant of Vehicle Routing Problem (VRP). VRPSDP has special constraints, namely requests and returns are carried out simultaneously. In this article we will use the Variable Neighborhood Descent (VND) algorithm to solve VRPSDP problems. There are two steps taken to use the VND algorithm on VRPSDP, namely finding an initial solution with the Insertion Heuristic algorithm and improving the position of the customer by using the neighborhood operator on the VND algorithm. The implementation of the VND algorithm on VRPSDP has been successfully made using the Borland Delphi 7.0 programming language. Inputs contained in the program are point position, distance between points, customer requests and returns and vehicle capacity. The output contained in the program in the form of routes that have been completed using an algorithm and output in the form of images of the final solution that has been obtained. Based on the results obtained, an example with 6 customers produces 3 routes with a total distance of 266 km, while an example with 10 customers produces 4 routes with a total distance of 100 km

ALGORITMA GRAVITIONAL EMULATION LOCAL SEARCH PADA CVRP DAN IMPLEMENTASINYA

Permasalahan optimalisasi distribusi dapat dipecahkan dengan menggunakan algoritma pada varian Vehicle Routing Problem (VRP). Salah satu varian dari VRP adalah Capacitated Vehicle Routing Problem (CVRP) yaitu dengan tambahan kendala kapasitas kendaraan yang identik. Algoritma Gravitational Emulation Local Search (GELS) dapat digunakan untuk menentukan solusi CVRP. Algorima GELS merupakan gabungan dari algoritma genetika dan local search (best improvement local search). Pada artikel ini dibahas langkah algoritma dan diimplementasikan ke dalam computer menggunakan aplikasi Borland Delphi 7.  Input program berupa ukuran populasi, probabilitas crossover, probabilitas mutasi, maksimum iterasi, kapasitas kendaraan, banyaknya titik, dan permintaan setiap customer. Output berupa hasil rute dengan jarak yang ditempuh serta divisualisasi rutenya dengan gambar graph. .Diberikan contoh penyelesaian permasalahan dengan contoh 7 titik terdiri dari satu depot dan enam customer. Hasil tampilan program berupa matrik bobot titik, permintaan, dan hasil berupa rute optimal. Aplikasi program GELS pada CVRP secara praktis dapat digunakan untuk penyelesaian optimasi distribusi

TWO PHASE HEURISTIC ALGORITHM (TPHA) PADA MULTIPLE TRAVELLING SALESMAN PROBLEM (MTSP) DAN IMPLEMENTASI PROGRAMNYA

Multiple Traveling Salesman Problem (MTSP) is one variant of Traveling Salesman Problem (TSP) which involves several salesmen in making a trip to visit several customers. In this article, the Two-Phase Heuristic Algorithm (TPHA) is used to solve MTSP problems. The algorithm classifies customers into several regions using the K-Means algorithm, which will then find a route solution for each region using a genetic algorithm. The MTSP problems that were resolved using TPHA were implemented into the Borland Delphi 7.0 programming language. Application testing was conducted using 21, 32, and 46 point cases

The effect of online project-based learning application on mathematics students’ visual thinking continuum in Covid-19 pandemic

The COVID-19 pandemic led to the implementation of the Work from Home (WFH) policy. The impact of this policy is to replace the process of teaching and learning activities by using an online learning system. In this industrial era 4.0, the integration of web applications is very much needed in problem-solving learning. One that can be used to integrate web applications in learning through project-based learning. The focus of this research is to study the effects of online project-based learning applications on mathematics students’ visual thinking continuum. Instruments used in the form of rubric virtual mind maps, audio-visual and virtual posters are used to observe students’ visual thinking continuum. The instrument was analyzed with the Rasch measurement model software named WINSTEPS. This study used one group pretest-posttest design to see the effect of integrating web applications in learning through project-based learning analyzed using SPSS. The results of instrument analysis for rubric virtual mind maps, audio-visual products, and virtual posters on measure person obtained good person reliability, MNSQ infit, and MNSQ OUTFIT the average rating is very good. For the ZSTD infit and the ZSTD outfit, the average value is close to 0.0 so that the quality of the person’s reliability is good. The results of the conformity quality of the items with the model studied from the fit order items obtained the value of Outfit mean square (MNSQ), Outfit Z-standard (ZSTD), and the value of Point Measure Correlation (Pt Mean Corr) for the three instruments met good criteria. The results of the analysis of paired samples test from 54 respondents obtained p <0.05 so that the base learning project has the effect of increasing students’ visual thinking continuum. Implementation of online project-based learning in mathematics learning is an alternative that can be used to improve students’ creative problem-solving skills in online learning

Peningkatan Daya Tarik dan Wawasan Wisatawan dengan Pembangunan Eco-Smart Mini Lab Sebagai Wisata Edukasi Alam

Penelusuran ragam potensi unggulan di Indonesia tidak akan pernah terlepas dari keindahan alamnya. Masyarakat perkotaan khususnya era millenial saat ini menggandrungi objek wisata yang berkonsep alam atau biasa dikenal dengan ekowisata. Terutama banyaknya potensi wisata alam yang ada di Kabupaten Malang Jawa Timur. Salah satu yang sudah ada yaitu wisata bumi perkemahan bedengan yang terletak di kecamatan Dau Kabupaten Malang. Sesuai dengan bidang dari sebagian besar tim pelaksana, maka disepakati untuk mengembangkan desain Eco-Smart Mini Lab berbasis solar cell sebagai konsep wisata alam edukasi dalam meningkatkan pengetahuan dan daya tarik wisatawan di area bumi perkemahan Bedengan. Eco-Smart Mini Lab berbasis solar cell merupakan bangunan laboratorium mini berkonsep alam yang di dalamnya berisi pengetahuan dan informasi terkait dengan wisata yang ada di Desa Selorejo seperti wisata Bumi Perkemahan Bedengan. Metode yang digunakan pada kegiatan ini yaitu metode demonstrasi dengan pendekatan diskusi kelompok dan studi kasus. Metode demonstrasi dipilih dikarenakan telah tersedianya alat sarana dan prasarana pendukung untuk melakukan pelatihan. Diskusi kelompok dan studi kasus dipilih untuk menentukan permasalahan (trouble) yang akan diambil pada kegiatan ini. Hasil dari kegiatan pegabdian ini meliputi: 1) kegiatan yang telah dilakukan terdiri dari pembuatan Eco-Smart Mini Lab, sosialisasi, dan pelatihan perawatan; 2) adanya peningkatan pendapatan wisata Bedengan meningkat; 3) terjadi peningkatan tata nilai masyarakat terkait dengan lapangan pekerjaan; dan 4) peningkatan wawasan pengunjung terkait dengan pembudidayaan jeruk di Bedengan. Kata kunci— wisata Bedengan, wisata alam, budidaya jeruk, potensi unggulan daerah AbstractExploring the variety of superior potential in Indonesia will never be separated from its natural beauty. Urban communities, especially the millennial era, currently love tourist objects with a natural concept or commonly known as ecotourism. Especially the large number of natural tourism potentials in Malang Regency. One that already exists is a tour of the bed campground located in Dau sub-district, Malang district. In accordance with the areas of most of the implementing team, it was agreed that a solar cell-based Eco-Smart Mini Lab design would be developed as a concept for educational nature tourism in increasing knowledge and tourist attraction in the Bedengan campground area. Eco-Smart Mini Lab based on solar cell is a mini laboratory building with a natural concept which contains knowledge and information related to tourism in Selorejo village such as Bumi Perkemahan Bedengan. The method used in this activity is the demonstration method with a group discussion approach and case studies. The demonstration method was chosen because of the availability of supporting facilities and infrastructure for conducting training. Group discussions and case studies were selected to determine problems (trouble) to be taken up in this activity. The results of service include: 1) activities that have been carried out consisting of making an Eco-Smart Mini Lab, socialization, and maintenance training; 2) increased tourism revenue for Bedengan increases; 3) there is an increase in community values related to employment; and 4) increasing visitors' insight related to citrus cultivation in Bedengan..Keywords— Bedengan village tourism, nature tourism, citrus cultivation, regional superior potentia

ALGORITMA GENERAL VARIABLE NEIGHBORHOOD SEARCH PADA CAPACITATED VEHICLE ROUTING PROBLEM WITH TIME WINDOWS DAN IMPLEMENTASINYA

The Capacitated Vehicle Routing Problem with Time Windows (CVRPTW) is one of the variants of the Vehicle Routing Problem (VRP), which is the problem of determining the optimal route from the depot to the consumer which is located spread out with different requests. In CVRPTW problem solving considers capacity and time constraints. Determining the optimal route can reduce costs and energy spent during the distribution process. The General Variable Neighborhood Search (GVNS) algorithm can be applied to the CVRPTW problem. The GVNS algorithm is an improvement on the VNS algorithm using RVND. The GVNS algorithm starts with finding the initial solution, continues with perturbation, and then the repair procedure is carried out. Perturbation and improvements to the GVNS algorithm are performed repeatedly according to the predetermined IterMax. The GVNS algorithm for CVRPTW will be implemented using the Borland Delphi 7.0 programming language. The product in the form of this application can be used more practically to solve CVRPTW problems using the GVNS algorithm.Keywords: Capacitated Vehicle Routing Problem with Time Windows (CVRPTW), General Variable Neighborhood Search (GVNS) Algorithm, Randomized Variable Neighborhood Descent (RVND

The Effect of Online Project-Based Learning Application on Mathematics Students' Visual Thinking Continuum in Covid-19 Pandemic

The COVID-19 pandemic led to the implementation of the Work From Home (WFH) policy. The impact of this policy is to replace the process of teaching and learning activities by using an online learning system. In this industrial era 4.0, the integration of web applications is very much needed in problem-solving learning. One that can be used to integrate web applications in learning through project-based learning. The focus of this research is to study the effects of online project-based learning applications on mathematics students' visual thinking continuum. Instruments used in the form of rubric virtual mind maps, audio-visual and virtual posters are used to observe students' visual thinking continuum. The instrument was analyzed with the Rasch measurement model software named WINSTEPS. This study used one group pretest-posttest design to see the effect of integrating web applications in learning through project-based learning analyzed using SPSS. The results of instrument analysis for rubric virtual mind maps, audio-visual products, and virtual posters on measure person obtained good person reliability, MNSQ infit, and MNSQ OUTFIT the average rating is very good. For the ZSTD infit and the ZSTD outfit, the average value is close to 0.0 so that the quality of the person's reliability is good. The results of the conformity quality of the items with the model studied from the fit order items obtained the value of Outfit mean square (MNSQ), Outfit Z-standard (ZSTD), and the value of Point Measure Correlation (Pt Mean Corr) for the three instruments met good criteria. The results of the analysis of paired samples test from 54 respondents obtained p &lt;0.05 so that the base learning project has the effect of increasing students' visual thinking continuum. Implementation of online project-based learning in mathematics learning is an alternative that can be used to improve students' creative problem-solving skills in online learnin