An experimental evaluation of slots versus porous strips for laminar-flow applications

Detailed mean velocity and disturbance amplitude measurements were conducted in a Blasius boundary-layer flow with wall suction applied at three downstream locations. The main emphasis was a direct comparison of the growth rate of the instability wave with discrete spanwise slots versus wide porous strips. The results demonstrate that the local effects of suction through slots or very narrow porous strips have a greater beneficial effect on the stability of the boundary-layer flow relative to the suction influence of a wide porous strip. Codes which use continuous suction for the growth rates of the instability waves to determine the suction quantities for a multiple series of slots will be quite conservative in the estimation of the suction quantity. Guidelines were provided for suction-chamber design and flow rates to minimize internal oscillations which propagate into the boundary-layer flow

Laser velocimetry in highly three-dimensional and vortical flows

The need for experimentally determined 3-D velocity information is crucial to the understanding of highly 3-dimensional and vortical flow fields. In addition to gaining an understanding of the physics of flow fields, a correlation of velocity data is needed for advanced computational modelling. A double pass method for acquiring 3-D flow field information using a 2-D laser velocimeter (LV) is described. The design and implementation of a 3-D LV with expanded capabilities to acquire real-time 3-D flow field information are also described. Finally, the use of such an instrument in a wind tunnel study of a generic fighter configuration is described. The results of the wind tunnel study highlight the complexities of 3-D flow fields, particularly when the vortex behavior is examined over a range of angles of attack

Magnetic anisotropy of YbNi4P2

We report on transport and magnetic measurements between 1.8 and 400 K on single crystalline YbNi4P2, which was recently reported to be a heavy fermion system with a low lying ferromagnetic transition at T_C=0.17 K, based on data from polycrystals. The tetragonal crystal structure of YbNi4P2 presents quasi-one-dimensional Yb chains along the c direction. Here we show that at high temperatures, the magnetic anisotropy of YbNi4P2 is dominated by the crystal electrical field effect with an Ising-type behaviour, which gets more pronounced towards lower temperatures. The electrical resistivity also reflects the strong anisotropy of the crystal structure and favours transport along c, the direction of the Yb chains.Comment: SCES 2011 proceedings, in pres

Tindak Pidana Penyertaan (Deelneming) Yang Melibatkan Anggota Polri

Tujuan dilakukannya penelitian ini adalah untuk mengetahui apa faktor yang mendorong terjadinya tindak pidana penyertaan yang melibatkan anggota Polri dan bagaimana proses penyelesaian tindak pidana penyertaan yang melibatkan anggota Polri. Dengan menggunakan metode penelitian yuridis normatif, maka dapat disimpulkan: 1. Bahwa dalam melakukan suatu tindak pidana penyertaan, anggota Kepolisian dipengaruhi oleh beberapa faktor baik dari dalam diri sendiri maupun lingkungan sekitarnya. Hal-hal tersebut dapat dicegah dengan mendekatkan diri kepada sang pencipta, dengan iman yang kuat insyah Allah dapat menjauhkan dari hal-hal yang merugikan banyak orang termasuk tindak pidana penyertaan. Dengan iman yang kuat, otomatis kepribadian juga baik dengan itu diharapkan oknum polisi dapat menjalankan tugas dan fungsinya sebagaimana yang telah diatur dalam undang-undang. Penegakan hukum juga akan semakin baik dan kepercayaan masyarakat terhadap polisi akan baik pula, masyarakat dapat mengerti dan mematuhi aturan-aturan yang ada, dengan meneladani oknum polisi tersebut. Di mata masyarakat hukum adalah polisi. 2. Dalam menyelesaikan tindak pidana penyertaan yang melibatkan anggota Polri, diselesaikan seperti tindak pidana pada umumnya di pengadilan negeri, setelah Polri memisahkan diri dari ABRI maka Polri tunduk pada peradilan umum bukan lagi pada peradilan militer. Mulai dari penyidikan, penuntutan ,sampai pada putusan semuanya dilakukan seperti pada perkara pidana pada umumnya, hal itu sesuai dengan PP RI Nomor 3 Tahun 2003 Tentang Pelaksanaan Teknis Institusional Peradilan Umum bagi Anggota Kepolisian Negara Republik Indonesia. Setelah mendapatkan putusan yang berkekuatan hukum tetap (inkracht) dari pengadilan negeri, maka selanjutnya akan dilakukan sidang komisi etik kepolisian sesuai dengan PERKAP (peraturan kepala kepolisian) RI Nomor 19 Tahun 2012 tentang Susunan Organisasi dan Tata Kerja Komisi Kode Etik Kepolisian Negara Republik Indonesia. Setelah sidang komisi etik kepolisian maka akan dilanjutkan dengan pemberhentian dengan tidak hormat(PTDH) terhadap oknum tersebut dan dilanjutkan dengan apa yang telah diputuskan pada sidang di pengadilan negeri

Natural killer cells in placentation and cancer: Implications for hypertension during pregnancy

Hypertension during pregnancy is the most common medical condition encountered during gestation. Despite this, knowledge of the mechanisms that underlie the disease and the development of new therapies are limited. Hypertension during pregnancy and some forms of cancer confer an increased risk to the development of cardiovascular disease later in life; one mechanism which may link these conditions is the involvement of natural killer (NK) cells. Whilst immunology and immunotherapy are well-developed areas in oncology; the complex mechanisms of the immune system in health and disease at the maternal-fetal interface are less well-defined. Natural killer (NK) cells have emerged as key immune cells involved in physiology and pathology of pregnancy. These small lymphocytes are present in the decidua (the uterine-specific uNK cells) and are distinct from peripheral NK cells. The uNK cell population plays a vital role in mediating trophoblast invasion and affecting decidual vascular remodelling whereas the role of the peripheral NK cell population during pregnancy is less well-defined. This review will give an overview of NK cell biology followed by a discussion of the current evidence for the role of uterine and peripheral NK cells at the maternal-fetal interface in health and disease. Furthermore, examples of NK cell research from cancer biology will be employed to inform future directions of research. By combining this knowledge from oncology where the field of immunotherapy has now matured into clinical trials; it is hopeful that new mechanisms can be elucidated to generate targets for similar therapeutic strategies for women with hypertensive pregnancies where interventions are needed