Judul: Desain dan Implementasi Sistem Terdistribusi dengan Model Replikasi Multi-master pada Basis Data untuk Optimasi Keandalan Sistem
Abstrak: An important factor in the usability of an information system service is security and reliability guarantee. Computer network reliability is defined as the ability to optimize functions in a particular period. Performance, availability, and security are factors influencing reliability. In term of ensuring the reliability, replication technique is one of the mechanisms that copy and distribute data from one database into another. It synchronizes between one or more databases that guarantee data consistency. Multi-master replication is a process that allows any computer can write and read data in a master database. When there is a change in one database master then other master will be updated automatically, and vice versa. A distributed system is a form of the system architecture in which computers are autonomous can communicate and share resources regardless of where the computer was located, and the platform used. Problems in both data processing in data loss and the backup method are still manual so that existing systems less reliable. Seeing these problems need to be constructed a prototype system that is more reliable both in thems of availability or system performance. The study was conducted at the Insistute of Science and Technology Al-Kamal using sample data and existing architecture. The existing system was engineered in a prototype that utilizes a distributed load balancing technology for the system. Furthermore, the research built a backup database with multi-master replication model. Multi-master replication method can improve the availability of the system model. The research resulted that data changes were not lost as long as the system could guarantee their connections. Performance distributed systems using a load balancer can maintain server availability. The system takes 0.731-second and 63.56 to show login page and student data. The number of connections did not affect tes-duration, however, it affected the reply time. F-value 0.11 form test duration and 0.07 for reply time proved the conclusion. The result of this research and model will be proposed as a new model to replace the existing system model.
Keyword: Distributed system, Multi-master, Reliability, Replication

Judul: Simulasi Master Data untuk Data Exchange Evaluasi Kinerja Dosen Berbasis Replikasi Basis Data
Abstrak: Integration of heterogenous databases is a difficult but important task. One of the benefits of integrated data is to ease the process of filling the lecturer’s performance evaluation forms. The required data to fill these forms are spreaded in various database of the existing systems. For example, the lecturer’s identity data are stored in the employee information system database, the education and teaching data are stored in the academic information system database, whereas the research and sevice data are stored in the research and journal information system database. One way to integrate these data is to create data master. This research presents a simulation to create a data master based on data replication which creates an application for the data provider. This application provides the requested data from the master database which are synchronized with the source database. The result of simulation shows that synchronization process will be done when there is a change from the source of database. This synchronization requires about one second to process eight thousand data. Thus, the master database will have the accurate data for filling the lecturer’s performance evaluation forms
Keyword: database synchronization, database replication, data master, database

Judul: Insecticidal Activity of Essential Oils Leaves of Cinnamomum spp. (Lauraceae) against Crocidolomia pavonana and Their Phytotoxicity on Broccoli Seedlings
Abstrak: Essential oils from leaves of 13 species of Cinnamomum were tested for their insecticidal activity on the cabbage head caterpillar Crocidolomia pavonana with leaf immerse method. The results showed that the treatment with 1% (w/v) essential oils leaves of C. celebicum, C. multiflorum, C. sintoc, and C. verum caused 21.45, 93.65, 60.30, and 76.10% mortality, respectively. Based on the results of phytotoxicity and insecticidal activity tests, C. multiflorum oil was further tested at 6 concentration levels. In all treatments, larval mortality has occurred at 24 hours after treatment (HAT) and increased at 48 HAT. LC50 of C. multiflorum oil at 24 and 48 HAT was 0.504 and 0.396%, respectively. The treatment with C. multiflorum oil at ≤0.31% did not inhibit the development of C. pavonana larvae. Determination of the chemical constituents of Cinnamomum oils were carried out by gas chromatography-mass spectrometry (GCMS). Totally, 345 compounds were identified. Methyleugenol constituted the main component (49.4%) of leaf essential oil of C. multiflorum and was assumed to be responsible for the insecticidal activity of the oil against C. pavonana larvae. LC50 of pure methyleugenol obtained at 0.365% (48 HAT) and 0.363% (72 HAT). The results showed that C. multiflorum was more effective with LC50 value equivalent to methyleugenol content of 0.32% (24 HAT) and 0.24% (48 HAT).
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