Physics

The binary star Par 1802 in the Orion Nebula presents an interesting puzzle in the field of stellar dynamics and evolution. Binary systems such as Par 1802 are thought to form from the same natal material and thus the stellar members are expected to have very similar physical attributes. However, Par 1802’s stars have significantly different temperatures despite their identical (within $3\\, {\\rm per\\, cent}$) masses of about 0.39 M⊙. The leading proof-of-concept idea is that a third companion gravitationally induced the two stars to orbit closer than their Roche limit, which facilitated heating through tidal effects. Here we expand on this idea and study the three-body dynamical evolution of such a system, including tidal and pre-main-sequence evolution. We also include tidal heating and mass transfer at the onset of Roche limit crossing. We show, as a proof-of-concept, that mass transfer combined with tidal heating can naturally explain the observed temperature discrepancy. We also...

Tujuan Penelitian ini untuk mengetahui peranan anggaran penjualan pupuk NPK mutiara pada CV. Sumber Agung di Sangatta sudah efektif atau belum efektif sebagai dasar perencanaan keuangan dan untuk mengetahui penyebab anggaran penjualan menjadi efektif atau tidak efektif sebagai dasar perencanaan keuangan maka dibuatlah penelitian ini. Permasalah yang dikemukakan adalah apakah anggaran penjualan pupuk NPK Mutiara pada CV. Sumber Agung di Sangatta sudah efektif sebagai dasar perencanaan keuanga. Dasar teori yang digunakan adalah akuntansi manjaemen dan penganggaran perusahaan  yang berfokus pada anggaran penjualan dan efektivitas. Alat analisis yang digunakan dalam penelitian ini adalah metode kuardat terkecil (least squre) dengan menggunakan analisis trend garis lurus (linier). Dengan anggaran penjualan pupuk NPK Mutiara sebagai dasar perencanaan keuangan CV. Sumber Agung selama tahun 2015 adaalah efektif digunakan, ini dapat dilihat dari anggaran penjulan pupuk NPK Mutiara yang menga...

Penelitian ini merupakan penelitian eksperimen dengan melaksanakan pembelajaran menggunakan model pembelajaran Kooperatif dengan Teknik Make a Match pada kelas eksperimen dan pembelajaran konvensional pada kelas kontrol. Populasi pada penelitian ini adalah siswa kelas X DKV di SMK Negeri 4 Padang dengan jumlah 64 siswa yang terbagi pada 2 kelas. Sampel diambil secara random sampling sebanyak 2 kelas yaitu kelas X DKV A dengan jumlah siswa sebanyak 32 orang sebagai kelas kontrol menggunakan model pembelajaran konvensional dan kelas X DKV B dengan jumlah siswa sebanyak 32 orang sebagai kelas eksperimen menggunakan model pembelajaran kooperatif dengan teknik Make a Match. Data hasil belajar diperoleh melalui tes sebanyak 25 butir soal objektif dengan lima pilihan jawaban. Kemudian data dianalisis dengan uji–t yang sebelumnya diuji normalitas sampel menggunakan uji Liliefors dan uji homogenitas. Rata-rata hasil belajar yang diperoleh siswa dalam penelitian ini untuk kelas eksperimen ada...

The paper presents the investigation results on the cylindrical DRA excited using single probe and anti-probe feeds, both on a finite ground plane. For the single probe case, an impedance bandwidth of 82% is achieved with the monopole like radiation patterns in the beginning of the bandwidth and the directional radiation patterns later on. Compared to this, there is reduction in the bandwidth to 68% with the anti-probe method of feeding the DRA, however there is significant improvement in terms of the radiation pattern gain and low cross polarization, right from the start to the end of the frequency band.

Znano je, da se poraba polimernih materialov iz dneva v dan povecuje. Posledicno izrazito narasca tudi kolicina polimernih odpadkov, ki vstopajo na trg. Cim hitreje je potrebno najti pot, ki nas bo vodila do ucinkovite izrabe sekundarnih polimernih surovin. To raziskovalno delo je opravljeno z namenom karakterizacije mehanskih in mikrostrukturnih lastnosti mesanic kompozitov s polimerno matico iz recikliranih polimerov v kombinaciji z razlicnimi polnili. V laboratoriju smo izvedli analizo ekstrudiranega materiala ter dolocili vpliv razlicnih pogojev izdelave na koncno karakteristiko samega kompozita. Delo predstavlja tudi možnosti uporabe taksnega materiala in standarde, ki jih taksen kompozitni produkt mora izpolniti za uspesen prodor na trg. Raziskava je pokazala, da imajo kompozitni materiali s polimerno matico iz recikliranega polimera karakteristike, ki so povsem primerljive s karakteristikami primarnih polimernih materialov. Potrdili smo tezo, da je iz recikliranih polimernih ...

The tension leg platform (TLP) is comprised of a buoyant hull that holds the platform's topside. A group of tendons under the columns connect the TLP to the foundation. The TLP is displaced in six degrees of freedom due to environmental loads. Tendons moor the TLP in vertical direction (heave and pitch). Surge amplitude (horizontal displacement) of TLP is greater than other degrees of freedom. Also heave motion is coupled with surge one. Therefore, it is important to introduce and implement a method to control and reduce displacement of the TLP in horizontal direction. In this paper, a passive control system (double horizontal tuned mass damper (TMD)) is used to mitigate the surge motion of TLP that is under regular waves. Also the efficiency and performance of double horizontal TMD and single horizontal TMD in reduction of surge response is compared.

The existence of plastic is useful for various kinds of packaging purposes in our activities. However, it takes around 500 years to decompose because these plastics are made from petroleum. Thus the production of plastic is in high dependency on oil stock. Due to this problem, an edible film can be an alternative packaging because it is biodegradable. Protein is the most potential biopolymer to be an edible film but still needs improvement. The enzymatic cross-linking reaction can be selected as a good method to improve protein-based edible film’s mechanical properties. In this study, catfish meat (Clarias batrachus) was used as a protein source to produce an edible film through enzymatic cross-linking reaction with The Transglutaminase enzyme (TG-ase). The results of this protein-based edible film showed an improvement in thickness where TG-05 is the thickest film. The solubility decreases from 42.86 % to 20 %. Tensile Strength (TS) and Elongation at Break (EAB) results have range ...

Airlines have introduced a back-to-front boarding process in response to the COVID-19 pandemic. It is motivated by the desire to reduce passengers' likelihood of passing close to seated passengers when they take their seats. However, our prior work on the risk of Ebola spread in aeroplanes suggested that the driving force for increased exposure to infection transmission risk is the clustering of passengers while waiting for others to stow their luggage and take their seats. In this work, we examine whether the new boarding processes lead to increased or decreased risk of infection spread. We also study the reasons behind the risk differences associated with different boarding processes. We accomplish this by simulating the new boarding processes using pedestrian dynamics and compare them against alternatives. Our results show that back-to-front boarding roughly doubles the infection exposure compared with random boarding. It also increases exposure by around 50% compared to a ty...

Abstract-In this paper we report a theoretical model of an Hgl. xCdxTe based photoconductive detector for characterizing the device in respect of voltage responsivity, quantum efficiency, detectivity and noise equivalent power. The results obtained on the basis of the model reveal that in ...

In this paper an analytical modeling of p + -Hg0.78Cd0.22Te/ n 0 Hg0.78 Cd0.22Te/CdZnTe, homojunction photodetector for long wavelength free space optical communication has been reported. The results obtained on the basis of analytical model have been compared and contrasted with the simulated results using ATLAS TM . The photodetector has been studied in respect of energy band diagram, electric field profile, doping profile, dark current, resistance area-product, quantum efficiency, spectral response, responsivity and detectivity by analytical method using closed form equations and also been simulated by using device simulation software ATLAS TM