Judul: Quality Control Analysis to Achieve Product Quality Standards for Butter Cookies at PT. XYZ.
Abstrak: Quality control analysis to achieve butter cookies standards at PT XYZ. This is done to find out the overall quality control process starting from the process of receiving raw materials, the production process, and the packaging process. Then from the conditions that do not match the parameters, then an analysis was carried out to determine the quality of the root of the problem. The analysis was carried out using a statistical quality control approach. The results showed a non-conformance in the production process into clean crumb cookies and dirty crumb cookies. In the process, it was divided into crumbs for each type of dough. In BP and SS cookies, the most common type of nonconformance occurred was chipped/cracked cookies, and in VR, HM, and CC cookies, the most common type of non-conformance was small-sized cookies. To find out whether the non-conformance that occured in the production process was controlled or not, the number of non-conformance product for 13 weeks was analyzed using a control chart, and the results of the analysis showed that the butter cookies production process was not under control, Analisis pengendalian mutu untuk mencapai standar untuk kue mentega di PT XYZ. dilakukan untuk mengetahui proses pengendalian mutu secara menyeluruh yang dimulai dari proses penerimaan bahan baku, proses produksi, dan proses pengemasan. Kemudian dari kondisi yang tidak sesuai dengan parameter kualitas perusahaan, maka dilakukan analisis untuk mengetahui akar permasalahan tersebut. Analisis dilakukan menggunakan pendekatan pengendalian mutu secara statistic. Hasil penelitian menunjukan ketidaksesuaian pada proses produksi dibedakan menjadi hancuran kue bersih dan hancuran kue kotor. Pada tahapan proses dibedakan menjadi hancuran pada setiap jenis adonan. Pada kue BP dan SS jenis ketidaksesuaian yang paling banyak terjadi adalah kue gompal/retak, dan pada kue VR, HM, dan CC jenis ketidaksesuaian yang paling banyak terjadi adalah kue berukuran kecil. Untuk mengetahui apakah ketidaksesuaian yang terjadi pada proses produksi terkendali atau tidak maka jumlah ketidaksesuaian selama 13 minggu di Analisa menggunakan grafik kendali, dan hasil Analisa menunjukan proses produksi kue mentega tidak terkendali.
Keyword: Quality control, Company standard, Butter cookies, Statistical quality control approach, control chart

Judul: Analysis of Quality Control to Achieve Quality Standards for Tempe Chips Products in Rumah Tempe Indonesia
Abstrak: Rumah Tempe Indonesia merupakan produsen keripik tempe di Indonesia yang memiliki pengendalian mutu yang diterapkan oleh perusahaan untuk mencapai mutu produk yang diinginkan, namun masih belum optimal dan kurang memuaskan terhadap mutu fisik keripik tempe. Masih terdapat produk yang belum memenuhi standar diantaranya keripik tempe yang menempel, hancur, mentah, dan gosong. Penelitian ini bertujuan untuk mengetahui proses produksi keripik tempe dalam usaha menghasilkan produk yang bermutu dan aman untuk dikonsumsi, menganalisis pengendalian mutu pada proses produksi keripik tempe, mengidentifikasi penyebab potensial yang memengaruhi mutu keripik tempe, dan membuktikan pengendalian mutu pada proses produksi tersebut terkendali atau tidak terkendali. Penelitian ini menggunakan alat bantu analisis yaitu statistical quality control. Prioritas masalah yang dipilih berdasarkan hasil analisis diagram pareto adalah keripik tempe menempel pada proses produksi keripik tempe dengan nilai frekuensi 45.72% dan dianalisis menggunakan grafik kendali yang menyatakan bahwa keripik tempe menempel tersebut tidak terkendali. Maka dilakukan percobaan perbaikan mutu dengan mengubah material minyak goreng yang digunakan dari minyak sawit menjadi minyak kelapa. Hasil uji coba perbaikan produk keripik tempe yang digoreng menggunakan minyak kelapa yaitu berkurangnya produk menempel yang dihasilkan sebesar 65.35% dan total produk defect yang dihasilkan sebesar 72.04% terhadap keripik tempe yang digoreng menggunakan minyak sawit., Rumah Tempe Indonesia is a producer of tempeh chips in Indonesia which has quality control implemented by the company to achieve the desired product quality, but it is still not optimal and the physical quality of the tempeh chips is not satisfactory. There are still products that don’t meet standards, including tempeh chips that stick, crumble, are raw and burnt. This research aims to understand the tempeh chips production process in an effort to produce quality products that are safe for consumption, analyze quality control in the tempeh chips production process, identify potential causes that influence the quality of tempeh chips, and prove whether the quality control in the production process is controlled or not. under control. This research uses analytical tools, namely statistical quality control. The priority problem chosen based on the results of the pareto diagram analysis was tempe chips sticking to the tempeh chips production process with a frequency value of 45.72% and analyzed using a control chart which stated that the tempeh chips sticking were uncontrolled. So an experiment was carried out to improve the quality by changing the cooking oil material used from palm oil to coconut oil. The results of trials to improve tempe chips products fried using coconut oil were a reduction in sticking products produced by 65.35% and a total of 72.04% defective products produced for tempeh chips fried using palm oil.
Keyword: coconut oil, palm oil, quality control, statistical quality control, tempe chips

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
Keyword: