Judul: Reformulasi Produk Body Spray Anti Nyamuk dan Uji Efektivitas Sediaan Body Spray Anti Nyamuk
Abstrak: Nyamuk adalah vektor berbagai penyakit menular berbahaya seperti malaria, DBD, dan chikungunya yang banyak dijumpai di wilayah tropis seperti Indonesia. Salah satu upaya pencegahannya yaitu dengan menggunakan body spray anti nyamuk berbahan alami yang dapat menggantikan body spray berbahan DEET yang memiliki efek samping berbahaya. Tujuan dari penelitian ini adalah untuk mengetahui bahan baku terbaik dalam pembuatan body spray anti nyamuk, mengetahui stabilitas dan karakteristik body spray yang terbentuk, dan mengetahui efektivitas sediaan body spray yang dihasilkan. Berdasarkan uji hedonik Essential Oil (EO) diperoleh EO terbaik yaitu EO D. Berdasarkan uji hedonik body spray anti nyamuk, diperoleh produk terbaik yaitu produk F yang menggunakan emulgator TEA Tween 80. Berdasarkan uji pH didapatkan produk F mengalami penurunan pH selama masa penyimpanan baik pada suhu ruang maupun oven. Uji homogenitas menunjukan semua sediaan F homogen. Uji organoleptik menunjukan tekstur dan aroma sediaan yang sama yaitu cair dan aroma khas ekstrak yang digunakan, tetapi pada sediaan yang disimpan disuhu oven dapat merusak warna menjadi bening kekuningan dan pemisahan fasa lebih cepat terjadi pada suhu oven. Pengujian efektivitas sediaan F terhadap nyamuk didapatkan hasil tertinggi 94,12% pada ulangan 1 jam pengamatan pertama dan hasil terendah 73,68% pada ulangan 1 dan 2 jam pengamatan keenam., Mosquitoes are vectors of various dangerous infectious diseases such as malaria, dengue fever and chikungunya which are often found in tropical regions such as Indonesia. One way to prevent this is by using natural anti-mosquito body spray which can replace body spray made from DEET which has dangerous side effects. The aim of this research is to determine the best raw materials for making anti-mosquito body spray, determine the stability and characteristics of the body spray formed, and determine the effectiveness of the body spray produced. Based on the hedonic Essential Oil (EO) test, the best EO was obtained, namely EO D. Based on the hedonic test for anti-mosquito body spray, the best product was obtained, namely product F which used the TEA Tween 80 emulsifier. Based on the pH test, it was found that product F experienced a decrease in pH during the storage period both at room temperature and oven. The homogeneity test shows that all F preparations are homogeneous. The organoleptic test shows that the texture and aroma of the preparation are the same, namely liquid and the characteristic aroma of the extract used, but the preparation stored at oven temperature can change the color to become clear yellowish and phase separation occurs more quickly at oven temperature. Testing the effectiveness of the F preparation against mosquitoes showed the highest result was 94.12% in the first 1 hour observation repeat and the lowest result was 73.68% in the sixth 1 and 2 hour observation repeat.
Keyword: Emulgator, Body spray anti nyamuk, Efektivitas mengusir nyamuk, Anti-mosquito body spray, Effectiveness in repelling mosquitoes

Judul: Market Analysis and Determination of the Cost of  Production for Mosquito Repellent Body Spray PT Eteris Prima Wiyasa
Abstrak: Peningkatan kasus demam berdarah dan penggunaan produk anti nyamuk yang mengandung DEET di pasaran mendorong PT Eteris Prima Wiyasa mengembangkan produk body spray anti nyamuk alami berbahan dasar minyak atsiri. Penelitian ini bertujuan mengetahui preferensi konsumen terhadap produk body spray anti nyamuk, merumuskan strategi bisnis dengan SWOT dan QSPM serta menentukan harga pokok produksi body spray. Tahapan penelitian terdiri dari fase eksplorasi, pendefinisian masalah, ideasi, pengembangan prototipe dan validasi. Berdasarkan hasil penelitian, terdapat tiga atribut produk yang dianggap sangat penting oleh konsumen dalam perancangan produk body spray anti nyamuk berupa efektivitas mengusir nyamuk, aroma dan harga. Strategi bisnis yang tepat untuk produk body spray anti nyamuk ini yaitu mempererat hubungan baik dengan pelanggan. Selain itu, didapatkan harga pokok produksi sebesar Rp 14.976/kemasan 100 ml dan harga jual produk sebesar Rp 34.500 dengan mark up 118% dan PPN 11%., The increasing cases of dengue fever and use of mosquito repellent products containing DEET on the market have prompted Eteris Prima Wiyasa company to develop a natural mosquito repellent body spray using essential oils. The research aims to determine consumer preferences for mosquito repellent body spray products, formulate business strategies using SWOT and QSPM, and determine the production cost of the body spray. The research stages include of exploration, problem definition, ideation, prototype development and validation. Based on the research results, there are three product attributes that are considered very important by consumers in the design of mosquito repellent body spray products, namely mosquito repelling effectiveness, aroma, and price. The right business strategy for this mosquito repellent body spray product is to strengthen customer relationships. In addition, the production cost is obtained at Rp 14.976/100 ml pack and the selling price of the product is Rp 34.500 with a markup of 118% and VAT of 11%.
Keyword: Business strategy, Production Cost, mosquito repellent body spray

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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