Scientific Journal of Informatics
Scientific Journal of Informatics published by the Department of Computer Science, Semarang State University, a scientific journal of Information Systems and Information Technology which includes scholarly writings on pure research and applied research in the field of information systems and information technology as well as a review-general review of the development of the theory, methods, and related applied sciences.
Articles
564 Documents
<![CDATA[Genetic Algorithm for Relational Database Optimization in Reducing Query Execution Time ]]>
<![CDATA[Hidayat, Kukuh Triyuliarno]]>;
<![CDATA[Arifudin, Riza]]>;
<![CDATA[Alamsyah, Alamsyah]]>
<![CDATA[ Scientific Journal of Informatics Vol 5, No 1 (2018): May 2018 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v5i1.12720
<![CDATA[The relational database is defined as the database by connecting between tables. Each table has a collection of information. The information is processed in the database by using queries, such as data retrieval, data storage, and data conversion. If the information in the table or data has a large size, then the query process to process the database becomes slow. In this paper, Genetic Algorithm is used to process queries in order to optimize and reduce query execution time. The results obtained are query execution with genetic algorithm optimization to show the best execution time. The genetic algorithm processes the query by changing the structure of the relation and rearranging it. The fitness value generated from the genetic algorithm becomes the best solution. The fitness used is the highest fitness of each experiment results. In this experiment, the database used is MySQL sample database which is named as employees. The database has a total of over 3,000,000 rows in 6 tables. Queries are designed by using 5 relations in the form of a left deep tree. The execution time of the query is 8.14247 seconds and the execution time after the optimization of the genetic algorithm is 6.08535 seconds with the fitness value of 0.90509. The time generated after optimization of the genetic algorithm is reduced by 25.3%. It shows that genetic algorithm can reduce query execution time by optimizing query in the part of relation. Therefore, query optimization with genetic algorithm can be an alternative solution and can be used to maximize query performance.]]>
<![CDATA[Decision Support System for Supplier Selection using Analytical Hierarchy Process (AHP) Method ]]>
<![CDATA[Juliana, Juliana]]>;
<![CDATA[Jasmir, Jasmir]]>;
<![CDATA[Jusia, Pareza Alam]]>
<![CDATA[ Scientific Journal of Informatics Vol 4, No 2 (2017): November 2017 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v4i2.12015
<![CDATA[Technological growth is characterized by a variety of technological finds and computational methods used to facilitate human work in the era of globalization that is the method of Decision Support System (DSS) that helps decision makers to use data and models to solve problems that are not Structured. Toko Harapan Baru in making decisions in determining the best suppliers still use intuition, analysis, calculation and comparison of the manual in determining the supplier of goods to his shop takes a long time, the difficulty of searching data because there is no data processing cause is quite complicated without any particular method which gives inaccurate results. Then, Toko Harapan Baru requires a system that can be a solution to the problem that is being encountered. The Analytical Hierarchy Process (AHP) method is a functional hierarchy to help decision-makers better in making decisions on many objective issues.]]>
<![CDATA[Metode Fuzzy Inference System untuk Penilaian Kinerja Pegawai Perpustakaan dan Pustakawan ]]>
<![CDATA[Alamsyah, Alamsyah]]>;
<![CDATA[Muna, Izza Hasanul]]>
<![CDATA[ Scientific Journal of Informatics Vol 3, No 1 (2016): May 2016 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v3i1.6136
<![CDATA[Penilaian kinerja pegawai merupakan aspek penting dalam manajemen sumber daya manusia yang efektif. Hal ini dikarenakan melalui penilaian kinerja pegawai, sebuah lembaga dapat mengetahui kondisi kerja dari pegawainya. Dalam melakukan penilaian kinerja, tiap lembaga mempunyai cara dan sistem tersendiri. Salah satu metode yang digunakan untuk mengukur kinerja pegawai perpustakaan dan pustakawan adalah metode fuzzy inference systems (FIS). FIS adalah suatu kerangka komputasi yang didasarkan pada teori himpunan fuzzy, aturan fuzzy dan penalaran fuzzy Adapun metode FIS yang dipakai adalah metode Sugeno orde 0 dengan variabel yang dipakai sebagai tolok ukur kinerja adalah produktivitas, profesionalitas, kedisiplinan, dan masa kerja. Keempat variabel ini digunakan untuk mengukur penilaian kinerja pegawai perpustakaan dan pustakawan. Hasil pengujian dan analisis yang telah dilakukan terhadap 50 pegawai, diperoleh skor kinerja pegawai tertinggi yaitu 90,89 dan skor kinerja terendah adalah sebesar 80,77. Dengan demikian dapat disimpulkan secara keseluruhan, kinerja pegawai perpustakaan dan pustakawan mendapat predikat sangat bagus.]]>
<![CDATA[Sistem Pengolahan Data Kegiatan Penelitian dan Pengabdian Kepada Masyarakat di Universitas Respati Yogyakarta ]]>
<![CDATA[Hamzah, Hamzah]]>
<![CDATA[ Scientific Journal of Informatics Vol 3, No 1 (2016): May 2016 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v3i1.5473
<![CDATA[Unit Penelitian dan Pengabdian pada Masyarakat merupakan salah satu unit di Universitas Respati Yogyakarta yang bertugas untuk mengelola kegiatan penelitian dan pengabdian kepada masyarakat yang dilakukan oleh dosen. Dalam proses pengolahan data kegiatan kegiatan penelitian dan pengabdian kepada masyarakat masih mengalami beberapa permasalahan yaitu belum adanya basis data yang digunakan untuk pengumpulan data rekam jejak kegiatan penelitian dan pengabdian kepada masyarakat oleh dosen dan sistem pengarsipan dokumen masih berbentuk kertas yang berdampak pada kerusakan dokumen, hilangnya dokumen, efisiensi ruang dan pencarian data. Penelitian yang dilakukan bertujuan menghasilkan luaran sistem informasi yang dapat melakukan proses pengolahan data penelitian dan kegiatan pengabdian kepada masyarakat yang dikelola oleh Unit Penelitian dan Pengabdian pada Masyarakat di Universitas Respati Yogyakarta. Pengolahan data mengacu pada komponen beban kerja dosen dibidang penelitian dan pengabdian kepada masyarakat. Metode pengembangan dilakukan dengan tahapan analisa sistem, perancangan sistem, coding dan implementasi sistem. Hasil pengembangan sistem informasi penelitian dan pengabdian masyarakat yaitu sebuah sistem yang dapat membantu Unit Penelitian dan Pengabdian pada Masyarakat dalam proses pengolahan data rekam jejak kegiatan penelitian dan kegiatan pengabdian kepada masyarakat yang dilakukan dosen.]]>
<![CDATA[A Hybrid Security Algorithm AES and Blowfish for Authentication in Mobile Applications ]]>
<![CDATA[Purwinarko, Aji]]>;
<![CDATA[Hardyanto, Wahyu]]>
<![CDATA[ Scientific Journal of Informatics Vol 5, No 1 (2018): May 2018 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v5i1.8151
<![CDATA[Nowadays, everything is within our grasp and with the mobile phones become easier. Its use is not limited to calls and SMS but has become a tool that can be used to serve business transactions, banking, academic of data through mobile applications. Tus, the security of authentication in the mobile application needs to be improved to avoid a hacker attack. This article presents an authentication in the mobile application to the server using a hybrid of cryptographic algorithm Advanced Encryption Standard (AES) and Blowfish. AES and Blowfish is a symmetric key algorithm is very fast and powerful. With the utilization of a large block size of AES and Blowfish to encrypt keys, AES security will be much more robust and complicated to attacked. So, it will be difficult for hackers to perform Man in the Middle (MitM) attacks.]]>
<![CDATA[K-Nearest Neighbor and Naive Bayes Classifier Algorithm in Determining The Classification of Healthy Card Indonesia Giving to The Poor ]]>
<![CDATA[Safri, Yofi Firdan]]>;
<![CDATA[Arifudin, Riza]]>;
<![CDATA[Muslim, Much Aziz]]>
<![CDATA[ Scientific Journal of Informatics Vol 5, No 1 (2018): May 2018 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v5i1.12057
<![CDATA[Health is a human right and one of the elements of welfare that must be realized in the form of giving various health efforts to all the people of Indonesia. Poverty in Indonesia has become a national problem and even the government seeks efforts to alleviate poverty. For example, poor families have relatively low levels of livelihood and health. One of the new policies of the Sakti Government Card Program issued by the government includes three cards, namely Indonesia Smart Card (KIP), Healthy Indonesia Card (KIS) and Prosperous Family Card (KKS). In this study to determine the feasibility of a healthy Indonesian card (KIS) required a method of optimal accuracy. The data used in this study is KIS data which amounts to 200 data records with 15 determinants of feasibility in 2017 taken at the Social Service of Pekalongan Regency. The data were processed using the K-Nearest Neighbor algorithm and the combination of K-Nearest Neighbor-Naive Bayes Classifier algorithm. This can be seen from the accuracy of determining the feasibility of K-Nearest Neighbor algorithm of 64%, while the combination of K-Nearest Neighbor-Naive Bayes Classifier algorithm is 96%, so the combination of K-Nearest Neighbor-Naive Bayes Classifier algorithm is the optimal algorithm in determining the feasibility of healthy Indonesian card recipients with an increase of 32% accuracy. This study shows that the accuracy of the results of determining feasibility using a combination of K-Nearest Neighbor-Naive Bayes Classifier algorithms is better than the K-Nearest Neighbor algorithm.]]>
<![CDATA[The Analysis of Implementation Business Model Canvas At The E-Marketplace Dipeta Company ]]>
<![CDATA[Purnawati, Ni Wayan]]>;
<![CDATA[Setyohadi, Djoko Budiyanto]]>
<![CDATA[ Scientific Journal of Informatics Vol 4, No 2 (2017): November 2017 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v4i2.9945
<![CDATA[In the internet Era as now everything is easily accessible, obtaining good information, education, services even trade. E-Marketplace as a new innovation for interaction between buyer and seller can also encourage micro medium to promote his business. www.pesansaja.com released by dipeta in the field of E-Marketplace of local culinary, which still require a lot of innovation to be able to attract customers and keep them. Innovation is also needed to be able to compete with other competitors on the E-Marketplace that engaged in the same. Hence the need for the implementation of the business model in this business model Canvas to get new business models to suit the wishes of the customer and an evaluation based on the strong and weak points of this business. The results of the implementation are expected to make the companys E-Marketplace is getting big and compete at a national level as an E-Marketplace of successful culinary attract customers]]>
<![CDATA[Implementasi Kriptografi Kunci Publik dengan Algoritma RSA-CRT pada Aplikasi Instant Messaging ]]>
<![CDATA[Arief, Ashari]]>;
<![CDATA[Saputra, Ragil]]>
<![CDATA[ Scientific Journal of Informatics Vol 3, No 1 (2016): May 2016 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v3i1.6115
<![CDATA[Instant messaging merupakan salah satu bentuk kemajuan teknologi komunikasi yang mempermudah penyampaian informasi. Saat ini, dengan semakin banyaknya pengguna aplikasi instant messaging berakibat pada dampak negatif berupa penyadapan data khususnya saat terjadi komunikasi yang bersifat rahasia. Algoritma RSA merupakan salah satu satu algoritma dalam kriptografi kunci publik. Pada proses enkripsi dan dekripsi digunakan kunci yang berbeda. Proses dekripsi algoritma RSA sering terjadi kendala karena ukuran kunci dekripsi yang relatif besar dapat memperlambat proses. Untuk mempercepat proses dekripsi, algoritma RSA dapat dimodifikasi dengan algoritma CRT (Chinese Remainder Theorem), sering disebut dengan Algoritma RSA-CRT. Implementasi algoritma kriptografi RSA-CRT pada aplikasi instant messaging pada panjang bit n mulai dari 56 bit sampai 88 bit, proses dekripsi RSA-CRT dua kali lebih cepat dibandingkan proses dekripsi RSA.]]>
<![CDATA[Poverty Data Model as Decision Tools in Planning Policy Development ]]>
<![CDATA[Mirza, Ahmad Haidar]]>
<![CDATA[ Scientific Journal of Informatics Vol 5, No 1 (2018): May 2018 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v5i1.14022
<![CDATA[Poverty is the main problem in a country both in developing countries to the developed countries, both in structural poverty, cultural and natural. That is, poverty is no longer seen as a measure of the failure of the Government to protect and fulfill the fundamental rights of its citizens but as a challenge of the nation to realize a fair society, prosperous and dignified sovereign. Various efforts have been made in determining government policy measures in an effort to overcome poverty, one of them by conducting a survey to assess the poor. The results of the survey of the various activities of the organization obtained a variety of database versions poverty to areas or locations. The information generated from the poverty database only includes recapitulation of poor people to the area or location. One step is to process the data on poverty in a process of Knowledge Discovery in Databases (KDD) to form a data mining poverty. Data mining is a logical combination of knowledge of data, and statistical analysis developed in the knowledge business or a process that uses statistical techniques, mathematics, artificial intelligence, artificial and machine-learning to extract and identify useful information for the relevant knowledge from various large databases.]]>
<![CDATA[Performance Appraisal of Seluma Districts Agricultural Extensionist with Fuzzy Simple Additive Weighting Method ]]>
<![CDATA[Suranti, Dewi]]>;
<![CDATA[Ikhsan, Mohamad]]>
<![CDATA[ Scientific Journal of Informatics Vol 4, No 2 (2017): November 2017 ]]>
Publisher : <![CDATA[Universitas Negeri Semarang ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.15294/sji.v4i2.12016
<![CDATA[Measuring the performance of an agricultural extensionist is essential for future evaluation and monitoring. An appraisal of agricultural extensionist workers should be performed to determine the achievements achieved by each agricultural extensionist agent. For that according to Permentan 2013 every Agricultural organization is obliged to conduct agricultural extensionist performance appraisal. This study aims to measure the peformance of agricultural extensionist of Seluma Regency by using Fuzzy Simple Additive Weighting (FSAW) method because this method determines the weight value for each attribute, followed by a ranking process that will select the best alternative from a number. This study aims to apply Fuzzy Simple Additive Wighted in the assessment of agricultural extensionist performance in Seluma district and to know the performance of agricultural extensionist workers in organizing agricultural extensionist. The system built is expected to facilitate BP3K sukaraja in carrying out routine performance appraisal of extensionist worker who has been a constraint in carrying out the appraisal performance appraisal. This system can result in accurate assessment of the performance of extensionist workers in accordance with the programs and work plans that have been made and implemented by agricultural extensionist.]]>
