Judul: Moisture Reduction of Kapuk and Rambutan Honey and Its Physicochemical
Abstrak: Madu merupakan komoditas hasil peternakan yang memiliki kandungan nutrisi cukup tinggi dan sangat bermanfaat bagi tubuh manusia, akan tetapi madu dapat mengalami kerusakan ketika diberi penanganan yang salah. Penelitian ini bertujuan menganalisis kualitas fisikokimia madu kapuk dan rambutan setelah diturunkan kadar airnya pada suhu ±30 °C. Penelitian ini menggunakan analisis deskriptif untuk membahas hasil yang didapatkan selama penelitian. Peubah yang diamati adalah kualitas fisikokimia madu antara lain kadar air, pH, kadar abu, viskositas, warna, dan kadar gula. Hasil penelitian menunjukkan perlakuan penurunan kadar air madu selama 8 jam pada suhu ±30 °C memiliki kadar air yang mendekati standar. Hal ini menyebabkan nutrisi madu pada perlakuan 8 jam penurunan kadar air memiliki hasil yang terbaik dalam kualitas fisikokimia madu kapuk dan madu rambutan meskipun pada persentase kadar abu madu rambutan dan nilai pH kedua jenis madu tidak berbeda. Kualitas fisikokimia madu keseluruhan pada penurunan kadar air di penelitian ini tidak mengalami penurunan., Honey is a comodities which has high nutrition and very useful for human body. However, honey’s quality can be decreased due to unproper handling. This study aimed to analyze physicochemical qualities of kapuk and rambutan honey which has been degradated in ±30 °C room temperature. This research used Descriptive Analysis for explaining the result. The variables observed are water content, pH, ash content, viscosity, honey color and sugar content as physicochemical quality of honey. The result of this study showed honey in 8 hours treatment and ±30 °C room temperature has highest decreased water content which closest to standard with significally different results (P<0,05). This causes honey nutrient at 8 hours treatment has the best physicochemical quality on both honey type even though ash content on rambutan honey and pH value on both type of honey has unsignificant different result (P>0,05). All criterias on physicochemical quality of honey in this study didn’t decreased.
Keyword: kapuk honey, rambutan honey, physicochemical quality, moisture reduction

Judul: Physicochemical Analysis of Kelulut Honey from Various Locations in Indonesia with Various Heating Temperatures
Abstrak: Madu kelulut dikenal sebagai stingless bee honey atau madu Meliponinae. Penelitian bertujuan untuk mengidentifikasi sifat fisikokimia madu Kelulut dari lokasi Serang, Bogor, Bangka, Sumedang, Garut, Klaten, dan Batu Ampar dengan ragam suhu pemanasan. Sifat fisikokimia yang diuji pada penelitain ini meliputi intensitas warna, total padatan terlarut, kadar air, viskositas, kelarutan, hidroksimetilfurfural, keasaman, gula pereduksi, dan sukrosa. pada madu dengan variasi suhu pemanasan yakni suhu ruang (25 °C), 65 °C and 121 °C. Hasil penelitian ini menunjukkan adanya perubahan sifat fisik maupun kimia yang terjadi pada madu diakibatkan pemanasan. Salah satunya adalah nilai gula pereduksi yang menunjukkan penurunan yang konsisten pada kedua ragam suhu pemanasan. Madu Garut pada perlakuan suhu normal memiliki kadar air sebesar 18,5 %b/b, keasaman sebesar 170 ml NaOH/kg, hidroksimetilfurfural sebesar 27,4 mg/kg, gula pereduksi sebesar 70,8 %b/b, dan sukrosa sebesar 1,4 %b/b, sehingga memiliki kesesuaian dan memenuhi Standar Nasional Indonesia. Hasil dari penelitian semua madu mengalami perubahan karakteristik fisik maupun kimia., Kelulut honey is known as stingless bee honey or Meliponinae honey. The study aimed to identify the physicochemical properties of Kelulut honey from Serang, Bogor, Bangka, Sumedang, Garut, Klaten, and Batu Ampar with various heating temperatures. The physicochemical properties tested in this research include colour intensity, total soluble solids, moisture content, viscosity, solubility, hydroxymethylfurfural, acidity, reducing sugar, and sucrose in honey with variations in heating temperature, namely room temperature (25 °C), 65 °C and 121 °C. The results of this study show that there are changes in physical and chemical properties occur in honey due to heating. One of them is the value of Reducing Sugar which shows a consistent decrease in both heating temperature variations. Garut honey in the normal temperature treatment has a moisture content of 18.5 %w/w, the acidity of 170 ml NaOH/kg, hydroxymethylfurfural of 27.4 mg/kg, reducing sugar of 70.8 %w/w, and sucrose of 1.4 %w/w, so it has conformity and meets the Indonesian National Standard. The results of the research all honey experienced changes in physical and chemical characteristics.
Keyword: honey, heating, physicochemistry, stingless bee

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
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