Judul: The Effect of Work Discipline and Work Motivation on Employee Performance at the Balangan Coal Mining Company
Abstrak: Pertambangan menjadi salah satu lapangan usaha yang menyumbang pertumbuhan ekonomi Indonesia. Balangan Coal merupakan sebuah perusahaan tambang batu bara yang berada di Balangan, Kalimantan Selatan yang memiliki misi untuk mengembangkan sumber daya manusia yang kompeten dan profesional. Pada perusahaan tambang Balangan Coal disiplin kerja dan motivasi kerja karyawan masih kurang. Tujuan dari penelitian ini adalah menganalisis pengaruh disiplin kerja dan motivasi kerja terhadap kinerja karyawan di perusahaan tambang Balangan Coal. Pendekatan yang dilakukan adalah dengan metode kuantitatif dan teknik pengumpulan data menggunakan kuesioner yang diberikan kepada karyawan Balangan Coal. Pengambilan sampel menggunakan metode non-probability sampling dengan teknik purposive sampling yaitu karyawan yang telah bekerja diatas 1 tahun. Jumlah sampel yang diteliti adalah 65 karyawan. Analisis data yang digunakan adalah dengan metode SEM-PLS. Hasil pengujian menyatakan bahwa disiplin kerja tidak memiliki pengaruh positif dan signifikan terhadap kinerja karyawan, motivasi kerja memiliki pengaruh positif dan signifikan terhadap kinerja karyawan, dan disiplin kerja memiliki pengaruh positif dan signifikan terhadap motivasi kerja., Mining has become one of the business sectors contributing to Indonesia's economic growth. Balangan Coal is a coal mining company located in Balangan, South Kalimantan, with a mission to develop competent and professional human resources. In Balangan Coal mining company, both work discipline and employee motivation are lacking. The purpose of this study is to analyze the influence of work discipline and work motivation on employee performance at Balangan Coal mining company. The approach used is quantitative method, and data collection technique involves distributing questionnaires to Balangan Coal employees. Sample selection was done using non-probability sampling method with purposive sampling technique, targeting employees who have worked for more than 1 year. The total sample size studied was 65 employees. The data analysis method used is Structural Equation Modeling-Partial Least Squares (SEM-PLS). The results showed that work discipline did not have a positive and significant influence on employee performance, work motivation had a positive and significant influence on employee performance, and work discipline had a positive and significant influence on work motivation.
Keyword: Employee Performance, Work Discipline, Work Motivation

Judul: The Influence of Good Corporate Governance on Financial Performance (Case Study on Coal Mining Companies Listed on the IDX)
Abstrak: Perusahaan pertambangan batubara dibangun untuk melayani dan menjaga kestabilan pasokan batubara domestik terutama pada PLTU sehingga dapat tercapai skala ekonomi yang besar. Agar hal tersebut terjadi maka perlu adanya tata kelola perusahaan yang baik guna untuk menciptakan nilai tambah ekonomis bagi pertumbuhan dan perkembangan perusahaan. Penelitian ini bertujuan untuk menganalisis perkembangan kinerja keuangan industry pertambangan batubara yang terdaftar di BEI dengan menggunakan economic value added serta menganalisis pengaruh struktur modal terhadap kinerja keuangan yang tergantung pada good corporate governance pada industri pertambangan batubara yang terdaftar di BEI Teknik pengambilan contoh pada penelitian menggunakan metode non- probability sampling dengan teknik purposive sampling. Penelitian ini mengambil sampel sebanyak 20 perusahaan pertambangan batubara yang terdaftar di BEI. Pengumpulan data dilakukan dengan teknik dokumentasi. Analisis data dilakukan dengan menggunakan MRA (Moderated Regression Analysis). Hasil penelitian menunjukkan bahwa variabel ukuran dewan direksi dapat memperlemah pengaruh negatif struktur modal terhadap kinerja keuangan sedangkan kepemilikan manajerial dapat memperkuat pengaruh negatif struktur modal terhadap kinerja keuangan. Terdapat beberapa hal yang dapat direkomendasikan berdasarkan implikasi manajerial dalam penerapan tata kelola yang baik yang dimoderasi oleh struktur modal terhadap kinerja keuangan yaitu ukuran dewan direksi dapat diperbesar menjadi kecenderungannya 5 orang berkompeten di bidangnya terutama bidang tambang produksi, keuangan, pengembangan, pemasaran dan manajemen risiko karena indikasi tersebut dapat memberikan komunikasi secara efektif terhadap dewan komsaris maupun komite audit guna mengoptimalkan pengawasan laporan keuangan.Perusahaan juga disarankan untuk meningkatkan persentase kepemilikan saham manajerial maksimal kisaran 60-70% kecenderungannya karena jika manajemen inti menginvestasikan dana nya ke perusahaan secara berlebihan maka porsi pembayaran dividen akan semakin besar juga., Coal mining companies are built to serve and maintain the stability of domestic coal supply, especially at PLTU so that large economies of scale can be achieved. In order for this to happen, it is necessary to have good corporate governance in order to create economic added value for the growth and development of the company. This study aims to analyze the development of the financial performance of the coal mining industry listed on the BEI using economic value added and analyze the effect of capital structure on financial performance which depends on good corporate governance in the coal mining industry listed on the BEI. The sampling technique in this study used a non-probability sampling method with a purposive sampling technique. This study took a sample of 20 coal mining companies listed on the IDX. Data collection is done by documentation technique. Data analysis was carried out using MRA (Moderated Regression Analysis). The results show that the variable size of the board of directors can weaken the negative influence of capital structure on financial performance while managerial ownership can strengthen the negative effect of capital structure on Financial performance. The results show that the variable size of the board of directors can weaken the negative influence. There are several things that can be recommended based on managerial implications in the implementation of good governance moderated by capital structure on financial performance, namely the size of the board of directors can be enlarged to tend to be 5 competent people in their fields, especially in the field of mining
Keyword: Economic Value Added, Good Corporate Governance, Kinerja Keuangan, MRA

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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