Judul: Carrageenan and Chitosan Application as an  Edible Coating to Extend Shelf Life Carnation (Dianthus caryophyllus L.)
Abstrak: In recent years, interest in edible flowers has increased. The problem that arises with edible flowers is that this commodity is perishable quickly, cannot be stored for long, and is required to be fresh. One alternative technology that can be done to increase the shelf life of carnations is to use carrageenan and chitosan edible coating applications. The purpose of this research was to examine the effect of using edible coatings of carrageenan and chitosan on changes in the quality of carnation flowers and to determine the best coating solution treatment based on the shelf life of the carnations produced. The results showed that the best treatment was coating with 0.1% chitosan solution (Q1) which was able to maintain the water content, weight loss, and hue values of 79.61%, 7.93%, and 26.62° to 6 shelf life with panelists' acceptance on score of 3 (from 0-5) based on color and freshness. Meanwhile, flowers without coating treatment (control) had moisture content, weight loss, and hue values of 74.01%, 11.68%, and 24.13°. However, these results may need to be reviewed with the same experiments in near future because the chitosan material used is categorized as technical material whose quality is unknown. The material used for coating should refer to Badan Standarisasi Nasional (BSN).
Keyword: Carnation, coating, carrageenan, chitosan, shelf life

Judul: Implementation of Active Packaging Technology to Extend The Shelf Life of Carnation Flowers (Dianthus Caryophyllus L.)
Abstrak: Pemanfaatan edible flower anyelir dalam beberapa tahun terakhir semakin populer di kalangan masyarakat. Kandungan air yang tinggi dalam bunga menimbulkan permasalahan karena bunga menjadi cepat rusak selama penyimpanan. Coating kitosan 0,1% terbukti mampu mempertahankan kualitas bunga anyelir selama 6 hari. Namun, penerapan edible coating cukup rumit sehingga dibutuhkan teknologi pascapanen lain yang lebih efisien. Oleh karena itu, teknologi kemasan aktif dengan bahan penyerap dapat dikembangkan pada bunga anyelir. Pada penelitian ini digunakan oxygen absorber untuk mengurangi konsentrasi O2 dalam kemasan dan silika gel untuk mengurangi H2O yang tertahan di dalam kemasan. Penelitian ini bertujuan untuk mengkaji pengaruh penggunaan kedua bahan penyerap pada kemasan bunga anyelir dan menentukan kombinasi yang terbaik. Perlakuan yang diberikan pada bunga adalah coating kitosan 0,1%, kemasan G1O1 (0,5 g silika gel dan 60 cc oxygen absorber), dan kemasan G2O2 (0,25 g silika gel dan 130 cc oxygen absorber). Hasil penelitian menunjukkan bahwa coating masih menjadi upaya terbaik untuk menjaga mutu bunga hingga hari ke-8 dengan nilai kadar air, susut bobot, nilai L, dan °hue selama penyimpanan sebesar 81,73%; 14,47%; 18,12; dan 12,64. Sementara itu, kemasan G1O1 merupakan perlakuan kemasan aktif terbaik dimana dapat mempertahankan kadar air, susut bobot, nilai L, dan °hue bunga sebesar 81,14%; 22,50%; 17,35; dan 14,40. Sebagai pembanding, nilai masing-masing parameter mutu pada kontrol pada akhir penyimpanan (8 hari) adalah 79,12%; 25,65%; 16,30; dan 9,26., The utilization of carnation as edible flower has been gaining popularity, but their high water content causes them to deteriorate quickly during storage. Previous research has shown that coating with 0,1% chitosan can maintain their quality for up to 6 days. However, the application of edible coatings is complex, so alternative postharvest technologies are needed. This study explores the use of active packaging technology with absorbent materials for carnation flowers. Oxygen absorbers were used to reduce oxygen concentration in the packaging, while silica gel was used to reduce water retention. The study aimed to determine the best composition of absorbent materials for the packaging. The treatments given to the flowers were coating with 0,1% chitosan, G1O1 packaging (0,5 g silica gel and 60 cc oxygen absorber), and G2O2 packaging (0,25 g silica gel and 130 cc oxygen absorber). The results showed that coating was still the most effective method for maintaining flower quality up to 8 days with values of moisture content, weight loss, L-value, and °hue during storage of 81,73%; 14,47%; 18,12; and 12,64. Meanwhile, G1O1 packaging is the best active packaging treatment which can maintain the moisture content, weight loss, L-value, and °hue of flowers by 81,14%; 22,50%; 17,35; and 14,40. For comparison, the values of each quality parameter in the control at the end of storage (8 days) were 79,12%; 25,65%; 16,30; and 9,26.
Keyword: Active packaging, carnation, edible flower, oxygen absorber, silica gel

Judul: Invers Drazin dari Matriks Toeplitz Singular
Abstrak: Matriks Toeplitz adalah matriks yang setiap unsur pada diagonal utama bernilai sama dan setiap unsur pada subdiagonal yang bersesuaian dengan diagonal utama juga bernilai sama. Matriks singular adalah matriks yang tidak bisa ditentukan inversnya. Akan tetapi, dapat diupayakan untuk ditentukan inversnya menggunakan invers matriks yang diperumum. Invers Drazin merupakan salah satu jenis invers matriks yang diperumum. Pada karya ilmiah ini ditentukan invers Drazin dari matriks Toeplitz singular dengan menggunakan metode Leverrier Faddeev. Kemudian, ditentukan invers Drazin dari matriks Toeplitz singular yang direpresentasikan sebagai penjumlahan segitiga bawah dan segitiga atas matriks Toeplitz berdasar pada teorema Gohberg dan Semencul., Toeplitz matrix is a matrix in with element on the main diagonal has the same value and on the subdiagonal corresponding to the main diagonal also has the same value. Singular matrix is a matrix that has no inverse. However, it can be attempted to determine the inverse using a generalized inverse matrix. Inverse Drazin is a type of generalized matrix inverse. This paper discussed the inverse Drazin for a singular Toeplitz matrix using the Leverrier Faddeev method. Then, the Drazin inverse of the singular Toeplitz matrix which is represented as a sum of products of lower and upper triangular Toeplitz matrix based on Gohberg and Semencul theorem.
Keyword: inverse Drazine, singular Toeplitz matrix