Judul: XML Retrieval dokumen bahasa indonesia menggunakan algoritme simnomerge
Abstrak: This research is comparing the retrieval of relevant documents to irrelevant documents by using 130 documents of medicinal plants and 20 queries. Simnomerge algorithm is used in this research because different XML contexts are kept separate for the weighting. Each query is divided into 5 queries for unstructured retrieval system, 8 queries for XML retrieval with XML context depth 1, and 7 queries for XML retrieval with XML context depth 2. The result of this research shows that the XML retrieval can improve performance of the retrieval system by getting more relevant documents. At the relevant documents, average precision of XML retrievals query for an XML context depth 1 is 0.911, or a 15.5% increase from the unstructured retrieval system. Average precision of XML retrievals query for XML context depth 2 is 0.981, or a 22.5% increase from the unstructured retrieval system. Meanwhile, for the irrelevant document the average precision of XML retrieval for XML context depth 1 is 0.246 or a 36.5% decrease from the unstructured retrieval system. The average precision of XML retrieval for XML context depth 2 is 0.329 or a 28.8% decrease from the unstructured retrieval system.
Keyword: 

Judul: Temu Kembali Informasi Dokumen XML dengan Pembobotan per Konteks
Abstrak: Various research in the field of information retrieval using XML documents have been conducted.However, those systems didnot consider the structure or tags of the XML documents. To improve the performance of the information retrieval system, we develop an information retrieval system using context weighting. Each weight which is implemented on each context is obtained from the result of correlation between the similarity of each context of the document to the queries and the similarity of the whole document to the queries using linear regression method. The information retrieval system that has been developed using the context weighting is evaluated by using 30 queries. It is found that this experiment decreases the average Mean Average Precision (MAP) value by 1.15% if compared with the information retrieval system without context.
Keyword: XMLtag weighting, information retrieval

Judul: Bifurkasi Hopf pada Model Siklus Bisnis Kaldor Kalecki tanpa dan dengan Waktu Tunda
Abstrak: Business cycle model is one of dynamical system models in economic. One of the business cycles model is Kaldor-Kalecki model. Kaldor-Kalecki business cycle model that is written in delayed defferential equations, is a business cycle model that involves gross product and capital stock of a company. In this paper Kaldor-Kalecki business cycle model is analyzed using both nondelay and delay in time of capital stock. By Taylor expansion for the time delayed model, an analysis of stability around the fixed points has been done. Furthermore, by using Hopf bifurcation theorem, it can be shown that there exists periodic orbits and limit cycle. In the nondelayed model, changing the parameter of goods market could lead to the occurrence of Hopf bifurcation and the existence of limit cycle. Similarly, for the delayed model, it has been shown that changing the time delay parameter may result in the occurrence of Hopf bifurcation and limit cycle.
Keyword: