Judul: Effect of Exchange Rate on Natural Rubber Exports to United States and Japan.
Abstrak: Natural rubber is one of prospective tropical plants for industry commodity product. This study examines the effect of the exchange rate on natural rubber exports to the United States and Japan quarterly over the period of 1996- 2010. This study then presents how the exchange rate effects the natural rubber exports in the short and long term. All variables used in this study are stationary at first difference and there is cointegration among variables, therefore we used VECM method. Using the VECM, we find that export volume and export price affects the natural rubber exports to the United States in the short term. Export volume affect the natural rubber exports to Japan, but export price, real exchange rate, international price, competitor price, and real GDP does not. In the long term, real exchange rate, international price and competitor price significantly affects natural rubber exports to the United States. The main conclusion is that the exchange rate has no significant effect on natural rubber exports to the United States and Japan in the short term, but has significant effect on natural rubber exports to United States in the long term.
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Judul: Competitiveness Analysis and Factors Affecting Trade Flow of Natural Rubber in International Market
Abstrak: Natural rubber is one of the plantation commodities, which plays an important role in the economic development of many countries. This commodity also provides job opportunities for many people, primarily for smallholder farmers. The supply of natural rubber in the world market is dominated by Thailand, Indonesia and Malaysia. According to UN-Comtrade, the natural rubber export share in 1987, Malaysia is the largest exporter. By period of 1990, however, the condition of trade had started to change, allowing Thailand and Indonesia to shift the position of Malaysia. This change was due to the improvement of natural rubber production in Thailand and Indonesia. Moreover, the Malaysian production decreased due to several factors. This situation illustrates the increasing competition between the three major producers of natural rubber in the international market over the last several decades. Thailand, Indonesia and Malaysia differ in their individual export destinations. However, according to the IRSG data, these three producing countries all exported to ten primary importing countries. As mentioned above, the competition between the main exporting countries is relatively high. Therefore, it is necessary for Thailand, Indonesia and Malaysia to individually focus on improving the quantity and quality of the product in order to remain competitive in the international rubber trade. According to the background information and problem statement, the aims of this research are, to analyze the competitiveness and the level of competition of the three major exporters of natural rubber in the international market and to identify the determinants that influence natural rubber export in international market. All data used in this study is secondary panel data, which is a combination of time series data and cross-sectional data. Time series data includes annual data from 2003 to 2013, while the cross-sectional data covers ten major export destinations of the three main natural rubber exporting countries, with the largest export volumes going to the United States, Japan, China, Singapore, the Republic of Korea, Germany, Canada, Brazil, India, and Belgium. The data used were obtained from Statistics Indonesia (BPS), the International Rubber Study Group (IRSG), the United States Department of Agriculture (USDA), the Centre d'Etudes et d'Informations Internationales prospectives (CEPII), UN Comtrade, the World Bank, and FAOSTAT. First method is Revealed Comparative Advantage (RCA). RCA is a method of analysis for determining the competitiveness of a player, while taking into account the comparative advantage of an individual, organization or country. The performance of natural rubber exports from exporting countries to importing countries is a variable that is measured by calculating the share of natural rubber exports to total exports of all commodities to destination countries, compared with the share of world exports to the destination countries. So that it can be quantitatively the ability or inability of three main exporting countries compete in international trade. And the second method is gravity model. The gravity model is used to analyze the economic factors that affect the flow of trade between two countries. According to Lineman (Lapipi, 2005), the gravity model is an econometric model that is used to analyze the effects of economic integration on trade, as well as
Keyword: Trade flow, Revealed Comparative Advantage, Natural Rubber, Competitiveness, Gravity model, Least Square Dummy Variable

Judul: berjudul Pelabelan Prima pada Graf Gurita (On) dengan Penambahan Simpul Duplikasi.
Abstrak: Setiap graf gurita adalah graf prima sedemikian sehingga pelabelan simpul pada graf gurita merupakan pelabelan simpul pada graf prima. Suatu Graf ( ( ) ( )) dapat dikatakan memiliki pelabelan simpul pada graf prima jika graf tersebut memenuhi fungsi bijektif ( ) { } dan untuk setiap sisi ( ( ) ( )) . Dalam karya ilmiah ini, akan ditunjukkan bahwa graf gurita memiliki pelabelan prima dan merumuskan graf gurita duplikasi dengan penambahan simpul dari simpul graf kipas ( ) graf gurita ( ), graf bintang ( ) graf gurita ( ), dan simpul utama pada graf gurita ( ) adalah graf prima dengan
Keyword: graf gurita, graf prima, pelabelan prima, penambahan simpul