Judul: Kesesuaian Periode Onset Kejadian Demam  Dengue (DD) dengan Onset Kejadian Hujan dan Surplus-Defisit Air di Provinsi Kalimantan Timur
Abstrak: Penularan Demam Dengue (DD) salah satunya dipengaruhi oleh unsur iklim, yaitu curah hujan. Kejadian penyakit DD seringkali bersamaan dengan terjadinya musim hujan. Untuk persiapan upaya preventif, informasi awal periode kejadian penyakit DD sangat diperlukan. Oleh karena itu, penelitian ini bertujuan mengidentifikasi periode onset kejadian DD berdasarkan onset kejadian hujan dan kondisi surplus-defisit air di Kalimantan Timur. Analisis periode onset dilakukan dengan menghitung anomali kumulatif data dengan rata-rata yang dihitung setiap tahun. Hasil analisis menunjukkan onset kejadian hujan sebagian besar terjadi pada dasarian I hingga II pada bulan Oktober, sedangkan onset kondisi surplus-defisit air terjadi pada periode yang sama hingga dua dasarian setelahnya, yaitu pada dasarian III Oktober hingga I November. Sementara itu, periode onset kejadian DD paling banyak terjadi pada bulan yang sama hingga dua bulan setelah onset kejadian hujan dan onset kondisi surplus-defisit air (Oktober-Desember), serta beberapa terjadi bukan setelah periode onset kejadian hujan maupun kondisi surplus-defisit air. Perbandingan kesesuaian antara periode onset kejadian DD dengan onset kejadian hujan dan kondisi surplus-defisit air tidak terlalu berbeda nyata walaupun onset kondisi surplus-defisit air terjadi pada satu hingga dua dasarian setelah onset kejadian hujan karena kesesuaiannya dengan periode onset DD dijelaskan dalam periode bulanan. Periode onset kejadian hujan tidak sepenuhnya dapat menjelaskan periode onset DD karena pola dan besarnya curah hujan yang terjadi pada periode sebelumnya dan saat terjadinya onset DD diduga juga berpengaruh, Dengue fever (DF) transmission is influenced by climate variables, including rainfall. DF incidences often occurs together with the onset of the rainy season. To prepare the preventive actions, early information on the period of DF incidences is needed. Therefore, this study was conducted to identify the onset period of DF events based on the onset of rainfall events and water surplus-deficit conditions in East Kalimantan. The onset period analysis was conducted by calculating the cumulative anomaly data with the average calculated annually. The analysis shows that the onset of rainfall events mostly occurred in the first to second decade of October, while the onset of water surplus-deficit conditions occurred in the same period until two decades later, that is in the third decade of October to the first of November. Meanwhile, the onset period of DF events mostly occurred in the same month to two months after the onset of rainfall events and the onset of water surplus-deficit conditions (October-December), and some occurred not after the onset period of rainfall events or water surplus-deficit conditions. The comparison of the suitability of the onset period of DF events with the onset of rainfall events and water surplus-deficit conditions was not significantly different even though the onset of water surplus-deficit conditions occurred one to two decades after the onset of rainfall events because the suitability of the DF onset period was described in monthly periods. The onset period of rainfall events was not able to fully explain the onset period of DF because of the pattern and amount of rainfall that occurred in the period before and during the onset of DF are also expected to influence.
Keyword: dengue fever, meteorological factor, onset period, rainfall, surplus-deficit

Judul: Kajian Potensi Transmisi Penyakit Demam Berdarah Dengue Berdasarkan Curah Hujan dan Suhu di Jawa Tengah
Abstrak: Dengue hemorrhagic fever (DHF) is a viral disease which has spread throughout Indonesia over the past 25 years. Ae. aegypti is the main vector of the disease. In Indonesia, especially in Central Java, there has been an upward trend in the incidence of dengue hemorrhagic fever. Therefore some efforts to suppress an outbreak of this disease had been done by the government with focus against the vector. This research aims to determine and mapping the transmission potential (TP) of DHF in Central Java under 4 principal seasons: rainy (December- February), transition 1 (March – May), dry (June-August) and transition 2 (September – November) at 3 rainfall conditions ( below normal, normal and above normal years) using vectorial capacity (VC) method. The results show that the maximum average VC for under normal years occur on December-February, whereas for normal and above normal years its occurs on March-May. In every rainfall condition, the minimum VC occur on June-August when rainfall is minimum. Based on resulted map from this research, in coastal area of northern and southern site of Central Java which is lowland area, TP were higher than in central area which is highland. TP on city with high population such as Tegal, Semarang, and Surakarta were higher. Nevertheless, between VC and incidence rate (IR) were significant with coefficient correlation 0.057, caused by there weren’t interventions between 35 districts in Central Java to supress the number of DHF disease in case of sanitation, vector controls (fogging, aerial spraying, making abate), immunity of society, etc.
Keyword: 

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
Keyword: