Judul: Designing Modified Atmosphere Packaging for  Straw Mushroom (Volvariella volvacea)
Abstrak: Jamur merang merupakan komoditas pertanian yang masih mengalami proses respirasi setelah dipanen dan memiliki laju respirasi yang tinggi menyebabkan cepat terjadinya pembusukan. Hal tersebut menyebabkan penjual jamur merang mengalami kerugian. Salah satu cara agar laju respirasi dapat diturunkan yaitu kombinasi penyimpanan dingin dengan pengemasan. Tujuan dari penelitian ini adalah menganalisis perubahan mutu jamur merang selama penyimpanan agar mendapatkan data yang valid terkait dengan kualitas jamur merang dalam penyimpanan. Metode MAP merupakan metode yang dapat menurunkan laju respirasi. Dalam merancang MAP dibutukan data laju respirasi jamur merang. Oleh karena itu, penelitian ini juga mengukur laju respirasi pada jamur merang selama penyimpanan. Suhu penyimpanan yang digunakan pada penelitian ini yaitu suhu 2 oC, 10 oC, 20 oC, dan suhu ruang. Parameter mutu yang diamati pada penelitian ini meliputi kadar air, susut bobot, kekerasan, dan perubahan warna. Ada empat tahapan penelitian dalam penelitian ini yaitu persiapan sampel, pengukuran mutu, pengukuran respirasi dilakukan menggunakan metode closed system, dan simulasi MAP. Hasil penelitian menunjukkan bahwa dalam penyimpanan suhu rendah laju respirasi akan semakin menurun. Kualitas penyimpanan jamur merang paling baik pada suhu 20 oC. Umur simpan jamur merang pada suhu 2 oC dan 10 oC hanya 1 hari setelah masa panen. Penyimpanan pada suhu ruang mampu bertahan selama 2 hari setelah masa panen dan penyimpanan pada suhu 20 oC mampu bertahan paling lama yaitu hingga 3 hari setelah masa panen. Jamur merang mengalami Chilling injury pada suhu 10 oC. Perancangan kemasan MAP dilakukan dengan simulasi berdasarkan data laju respirasi untuk mendapatkan komposisi gas O2 dan CO2 setimbang dalam kemasan.
Keyword: MAP, mushroom, respiration rate, storage temperatur

Judul: Pengemasan atmosfer termodifikasi pada jamur merang (Volvariella volvacea) blansir
Abstrak: Straw mushroom has a shelf life of 12 hours if left at room condition. This condition can be fixed by modified atmosphere packaging (MAP) application. The aim of this research was to obtain the best package design for modified atmosphere packaging of blanching straw mushroom. Before packaging, mushrooms treated blanching using hot water that serves to reduce the possibility of oxidation reactions. The addition of preservative aims to slow and inhibit the browning process of destructive microorganism, slow down, cover up or withhold the process of fermentation, putrefaction, acidification or other decomposition of destructive microorganism. Design of the package consisted of package size, number of perforation, and diameter of perforation. This research was also aimed to determine the best storage temperature. The parameters that observed during storage time were weight decrease, hardness, whiteness level, and the level of distortion. Each treatment had different perforation number and storage temperature. Perforation number that observered were 2, 4 and 8. Perforation diameter that used was 5 mm. While storage temperature that used were 5°C, 15°C, and 25°C. Each treatment made to twice repetition and stored for 14 days. The analysis done every 2 days. Every broken sample was not physically analyzed. During storage time weight, hardness, color, and quality decrease of straw mushroom is had happened thoroughly. Each package treatment had different effect on measured parameter. The result showed that package design of polypropylene plastic bag with 4 perforations and 5 mm perforation diameter that storaged in 15°C temperature was the best design to pack fresh straw mushroom. This package design was able to maintain mushroom quality for 10 days long, whereas other treatments were only able to maintain mushroom quality less than 10 days long. That package design was able to create optimum atmosphere compotition to pack mushroom so metabolism rate could be suppressed. Else, low storaging temperature could also suppressed metabolism rate as well as inhibited the growth of destructive microorganism. The result of mushroom measuring in that package at 10th day were weight decrease of 19:22%, hardness of 12.53 mm, whiteness level of 68.9, the level of damage by 38.49%. The damage indication that suffered by straw mushroom so it unable to consume were mushroom changed in color to brown, flabby and had decomposed smell.
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: