Judul: Study of Dairy Cattle Diseases Incidence Rate in Koperasi Serba Usaha (KSU) Tandangsari Sumedang 2014-2019
Abstrak: Studi ini bertujuan untuk mengetahui kejadian kasus penyakit pada sapi perah yang sering terjadi dan dugaan hubungannya dengan cuaca serta faktor lain di KSU Tandangsari, Sumedang. Data studi diambil dari laporan mahasiswa PKL PPDH FKH IPB periode 2014-2019. Data direkap dalam bentuk periode tiga bulanan berturut-turut (trimester). Penyakit yang dibahas pada studi ini yaitu 10 kejadian penyakit yang paling sering dilaporkan. Sebanyak 10 penyakit tersebut yaitu mastitis klinis, hipokalsemia, timpani rumen, enteritis, endometritis, laminitis, indigesti rumen, abses, carpal/tarsal arthritis, dan left displaced abomasum (LDA). Total penyakit yang dilaporkan berjumlah 34 penyakit dengan jumlah kasus yang terjadi dari total penyakit tersebut sebanyak 358 kasus. Faktor cuaca diduga berpengaruh terhadap tingkat kejadian penyakit mastitis klinis, hipokalsemia, endometritis, laminitis, dan LDA. Penyakit lain seperti timpani rumen, abses, indigesti rumen, carpal/tarsal arthritis, dan enteritis belum dapat diduga dipengaruhi oleh kondisi cuaca karena kejadian kasus yang hampir sama jumlahnya pada kedua musim. Kejadian penyakit yang sering terjadi juga dapat dipengaruhi oleh faktor lain seperti kebersihan dan sanitasi kandang, perubahan dan komposisi pakan, perkembangan mikroorganisme kandang, dan penggunaan material pada kandang yang kurang tepat., The objectives of this study were to analyze the incidence rate of dairy cattle internal diseases case and the alleged relationship with weather and external factors at KSU Tandangsari, Sumedang. The study data was taken from the reports of PKL PPDH FKH IPB students for the period 2014-2019. The data was recapitulated in the form of three consecutive months (trimester). The diseases discussed in this study were the 10 most frequently reported disease cases which were clinical mastitis, hypocalcemia, tympanic rumen, enteritis, endometritis, laminitis, rumen indigestion, abscess, arthritis carpal/tarsal, and left displaced abomasum (LDA). The total number of diseases reported were 34 variants of cases from 358 individual cases. Weather factors were assumed to affect the incidence of clinical mastitis, hypocalcemia, endometritis, laminitis, and LDA. Other diseases such as rumen tympanic, abscess, rumen indigestion, carpal/tarsal arthritis, and enteritis cannot be predicted to be influenced by weather conditions because the cases incidence is almost similar in both seasons. The disease incidence can also be influenced by other factors such as cleanliness and sanitation of the cage, changes and composition of feed, the development of microorganisms in the cage, and the use of material in the cage which was not appropriate.
Keyword: Dairy cattle, Incidence of disease, KSU Tandangsari, Weather factors

Judul: Analysis of the Incidence Rate of Surgical Disease in Dairy Cows at the KPSBU Lembang, West Java 2015-2019
Abstrak: Studi ini bertujuan mengidentifikasi tingkat kejadian kasus penyakit bedah yang sering terjadi pada sapi perah dan dugaan hubungannya dengan cuaca serta faktor lain di Koperasi Peternak Sapi Bandung Utara (KPSBU) Lembang, Jawa Barat pada periode tahun 2014-2019. Data kejadian penyakit diperoleh dari buku Laporan Praktik Lapang Pelayanan Kesehatan Klinik Sapi Perah oleh mahasiswa PPDH FKH IPB di KPSBU Lembang periode tahun 2015-2019. Kejadian penyakit dikelompokkan berdasarkan trimester waktu 12 bulan yaitu trimester pertama (bulan Januari-Maret), trimester kedua (bulan April-Juni), trimester ketiga (bulan Juli-September), dan trimester keempat (bulan Oktober-Desember). Data kejadian penyakit dibandingkan dengan dinamika cuaca di daerah KPSBU Lembang. Lima besar kasus penyakit bedah yang terjadi di KPSBU Lembang adalah arthritis, pododermatitis, timpani, Dislokasi Abomasum (DA), dan abses. Penyakit yang diduga berhubungan dengan cuaca yaitu arthritis, pododermatitis, timpani, dan dislokasi abomasum. Penyakit yang diduga tidak berhubungan dengan cuaca yaitu abses., This study aims to identify the incidence of surgical disease cases that often occur in dairy cows and its suspected correlation with weather and other factors in the Koperasi Peternak Sapi Bandung Utara (KPSBU) Lembang, Jawa Barat year 2014-2019. Data was collected from Laporan Praktik Lapang Pelayanan Kesehatan Klinik Sapi Perah written by PPDH IPB students at KPSBU Lembang year 2015-2019. Diseases occurence are divided based on trimester which is the first trimester (January-March), second trimester (April-June), third trimester (July-September), and fourth trimester (October-December). Disease incidence data is compared with weather dynamics at Lembang region. The top five cases of surgical disease that occurred at KPSBU Lembang were arthritis, pododermatitis, tympani, Dysplasia Abomasum (DA), dan abscess. Diseases that are suspected to have a direct correlation to the weather are arthritis, pododermatitis, tympani, Dysplasia Abomasum (DA). Diseases that are suspected to not have a direct correlation to the weather are abcess.
Keyword: dairy cows, KPSBU Lembang, surgical diseases, trimester, weather

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.
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