Judul: Daya Tahan Lapisan Finishing Interior Pada Lima Jenis Kayu Bahan Baku Alat Permainan Edukatif
Abstrak: Minat pasar terhadap kayu hutan rakyat, khususnya produsen mainan berbahan baku kayu terus meningkat, sejalan dengan makin terbatasnya pasokan kayu dari hutan alam. Namun kayu-kayu yang berasal dari hutan rakyat tergolong memiliki kualitas penampilan yang rendah dan tidak awet. Finishing merupakan salah satu solusi untuk mengatasi masalah tersebut. Kini telah dikembangkan bahan finishing berpelarut air (waterbased finishes) yang aman bagi lingkungan dan tidak mengandung bahan kimia berbahaya yang dapat mengancam kesehatan manusia. Suatu penelitian telah dilakukan untuk mengetahui daya tahan lapisan finishing berpelarut air (waterbased lacquer Propan dan acrylic wood paint Treinoc) pada 5 jenis kayu, bahan baku alat permainan edukatif (APE) dari hutan rakyat. Jenis kayu rakyat yang diteliti adalah kayu Jati, Trembesi, Mahoni, dan Nangka, sebagai pembanding diuji juga jenis kayu yang secara internasional sangat populer sebagai bahan baku APE yaitu Spruce (Picea sitchensis). Jenis pengujian meliputi ketahanan terhadap bahan kimia rumah tangga, hot and cold test, dan cross cut test. Hasil pengujian menunjukkan bahwa lapisan finishing tahan terhadap hot and cold test, sehingga diklasifikasikan ke dalam kelas 10 (dengan permukaan sama sekali tidak bercacat). Lapisan yang terbentuk juga tahan terhadap bahan kimia rumah tangga yang diujikan, berupa susu kental manis, dan selai strawberry sehingga diklasifikasikan ke dalam kelas 10, sementara itu ketahanan lapisan finishing terhadap margarin pada kayu Nangka pada kondisi basah dan kering menggunakan waterbased lacquer, serta pada kondisi basah menggunakan acrylic wood paint tergolong lemah. Pada hasil pengujian daya lekat cat (cross cut test), nilai kekuatan bervariasi dari kelas 0B, sampai dengan 5B. Kayu Nangka dan Jati dalam kondisi basah yang dilapisi waterbased lacquer dan acrylic wood paint memiliki nilai kekuatan daya lekat yang paling lemah sehingga digolongkan ke dalam kelas 0B. Kekuatan daya lekat yang terbesar terdapat pada kayu Spruce dan Trembesi (finishing dengan cat Propan dan Treinoc), Jati (finishing dengan cat Propan), serta Mahoni (finishing dengan cat Treinoc) , sehingga digolongkan pada kelas 5B.
Keyword: Kayu Rakyat, Waterbased, Finishing, Uji Cross Cut, Spruce

Judul: Daya Tahan Lapisan Finishing Interior Pelarut Air pada Kayu Jati, Kamper, dan Pinus.
Abstrak: The limited supply of wood from natural forests makes markets interest to wood from plantation forest increase. However, the wood comes from plantation forests considered to be low in quality, including durability. Finishing is one of the solutions to overcome these problems. In this present day there has been developing water based finishing materials (waterbased finishes) that is safe for the environment and does not contain harmful chemicals that can threaten human health. A study has been conducted to determine the durability of the water based finishing layer (Impra Aqua and Sayerlack Waterborne) on Teak (Tectona grandis), Camphor (Dryobalanops aromatica), and Pine (Pinus merkusii). The type of testing conducted covers on the hot and cold test, resistance to household chemical materials, and cross-cut test. The test results showed that the finishing layer is resistant to the hot and cold test, thus can be classified into class 10 (with a completely unblemished surface). The Layer formed by Impra Aqua finishing material is also resistant to all household chemicals tested, so it is classified into class 10. Meanwhile the layer resistance of Sayerlack Waterborne finishing against ballpoint ink tend to be less powerful, so it is classified into class 9, but the finishing materials is resistant to chemicals such as Povidone-iodine. In the test results of paint adhesion (cross cut test), teak wood in wet conditions coated with both types of finishing materials has the weakest adhesion strength, so it is classified into class 3B. Meanwhile, finishing layer for all the wood samples under dry conditions have very strong adhesion, so it is classified in class 5B.
Keyword: Bogor Agricultural University (IPB), Sayerlack Waterborne, Impra Aqua, Hot and cold test, Cross cut test, Finishing, Waterbased

Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
Keyword: