90,222 research outputs found
“O/F shift” in hybrid rockets
No full textFor most hybrid rocket systems, oxidizer to fuel ratio (O/F) changes over time due to 1) natural growth of the fuel port diameter and 2) oxidizer flow rate variations, if throttling is employed. This phenomenon, which is referred to as “O/F shift”, leads to a reduction in motor performance. Note that liquid or solid rocket motors are not subject to temporal O/F variations, which is wrongfully considered as one of the most critical disadvantages of hybrid rockets. In this paper, the effect of “O/F shift” is quantified for hybrid rocket motors. Analytical formulas for the temporal O/F variation and the overall c* efficiency drop associated with the variation has been derived for single circular port motors. It has been shown that for a typical motor, c* efficiency drop due to O/F variation is well below 0.2%, a value which is too small to be measured in an actual motor test. It is also shown that for a wagon wheel type multiport configuration (with triangular ports), efficiency drop is significantly worse than the single circular port case. Even for the multiport systems, the shift does not have a controlling effect on the overall efficiency of the motor. A number of strategies have been outlined to control the adverse effects of O/F variation in a hybrid rocket. For a single circular port design with limited throttling, no mitigation is required. For systems with deep throttling requirements, aft oxidizer injection seems like a viable strategy to retain a high level of overall efficiency
Arif Nihat Asya ve Kubbe-i Hadra
No full textTaha Toros Arşivi, Dosya No: 411-Arif Nihat Asya.Not : Gazetenin "Kitaplar ve Gerçekler" köşesinde yayımlanmıştır
The Process of Urbanisation in Pakistan, 1951–81
No full textThe current level of urbanisation in Pakistan, approximately 33 percent in 1998, is not high by global standards. But it is commonly linked with unemployment, underemployment, shortage of housing, transport and other infrastructure like water supply and sewerage. Compared to other areas of population dynamics, such as fertility and mortality, studies in the field of urbanisation and internal migration in Pakistan are rather limited. During the last three decades hardly half a dozen studies could be added in the field of urbanisation. These studies are primarily based on data generated by the different censuses. After the 1979 Population Labour Force and Migration (PLM) Survey, no nationally representative survey addressing the issue of urbanisation and internal migration could be carried out. Even regional studies could not be conducted during the last two decades. The present study is designed to utilise the 1998 census data to investigate urban population growth, pace (or tempo) of urbanisation and components of urban growth for the period of 1981–98.
KONSTRUKSI PASANGAN CALON DALAM PILGUB JATENG 2008 OLEH MEDIA MASSA (KASUS PEMBERITAAN JAWA POS RADAR SEMARANG DAN SUARA MERDEKA)
No full textPilgub Jateng 2008 adalah pemilihan kepala daerah langsung pertama yang
terjadi di Jawa Tengah. Ada lima pasangan yang mencalonkan diri sebagai
gubernur-wakil gubernur. Mereka adalah Bambang Sadono-M. Adnan (Partai
Golkar), Agus Soeyitno-Kholiq Arif (PKB), Sukawi Sutarip-Sudharto (Partai
Demokrat-PKS), Bibit Waluyo-Rustriningsih (PDI-P) dan HM. Tamzil-Rozaq
Rais (PPP-PAN). Mekanisme pemilihan langsung berakibat jarak antara pasangan
calon dengan pemilih menjadi semakin dekat sehingga setiap pasangan calon
dituntut untuk memanfaatkan media dalam membangun citra positif. Dalam hal
ini peran media sebagai sarana komunikasi politik menjadi cukup vital. Bagi
pasangan calon, media adalah sarana strategis untuk menyebarluaskan pesan
politik kepada khalayak. Media sebagai salah satu sumber informasi bagi
masyarakat harus mampu menjalankan fungsinya dengan baik dengan berpegang
pada netralitas. Namun, dalam operasionalnya media selalu dipengaruhi faktor
internal dan eksternal yang membuat mereka tidak dapat sepenuhnya objektif.
Media bukanlah institusi yang bebas nilai. Isi media tidaklah merefleksikan
realitas yang ada namun mengkonstruksikan serangkaian fakta yang terjadi.
Metode triangulasi digunakan untuk mengetahui bagaimana harian Jawa
Pos Radar Semarang dan Suara Merdeka mengkonstruksikan masing-masing
pasangan calon. Juga untuk mengetahui kecenderungan pemberitaan serta politik
redaksional masing-masing media. Objek penelitian yang dipilih adalah beritaberita
tentang pasangan calon di harian Jawa Pos Radar Semarang dan Suara
Merdeka pada halaman satu dan rubrik khusus selama 26 Maret-22 Juni 2008.
Hasil penelitian menunjukkan bahwa harian Jawa Pos Radar Semarang
berusaha responsif dengan isu-isu politik memberikan konstruksi yang favorable
kepada pasangan Agus Soeyitno-Kholiq Arif, Bibit Waluyo-Rustriningsih dan
HM. Tamzil-Rozaq Rais. Sebaliknya, mereka memberikan konstruksi
unfavorable kepada pasangan Bambang Sadono-M. Adnan dan Sukawi Sutarip-
Sudharto. Sedangkan Suara Merdeka memilih gaya pemberitaan yang aman dan
tidak tendesius kepada masing-masing pasangan calon. Hasilnya, mereka
cenderung mengkonstruksikan pasangan Bambang Sadono-M. Adnan, Bibit
Waluyo-Rustriningsih dan HM. Tamzil-Rozaq Rais dengan bingkai yang
favorable. Sedangkan pasangan Agus Soeyitno-Kholiq Arif dan Sukawi Sutarip-
Sudharto dalam bingkai unfavorable.
Pilgub Jateng 2008 adalah pemilihan kepala daerah langsung pertama yang
terjadi di Jawa Tengah. Ada lima pasangan yang mencalonkan diri sebagai
gubernur-wakil gubernur. Mereka adalah Bambang Sadono-M. Adnan (Partai
Golkar), Agus Soeyitno-Kholiq Arif (PKB), Sukawi Sutarip-Sudharto (Partai
Demokrat-PKS), Bibit Waluyo-Rustriningsih (PDI-P) dan HM. Tamzil-Rozaq
Rais (PPP-PAN). Mekanisme pemilihan langsung berakibat jarak antara pasangan
calon dengan pemilih menjadi semakin dekat sehingga setiap pasangan calon
dituntut untuk memanfaatkan media dalam membangun citra positif. Dalam hal
ini peran media sebagai sarana komunikasi politik menjadi cukup vital. Bagi
pasangan calon, media adalah sarana strategis untuk menyebarluaskan pesan
politik kepada khalayak. Media sebagai salah satu sumber informasi bagi
masyarakat harus mampu menjalankan fungsinya dengan baik dengan berpegang
pada netralitas. Namun, dalam operasionalnya media selalu dipengaruhi faktor
internal dan eksternal yang membuat mereka tidak dapat sepenuhnya objektif.
Media bukanlah institusi yang bebas nilai. Isi media tidaklah merefleksikan
realitas yang ada namun mengkonstruksikan serangkaian fakta yang terjadi.
Metode triangulasi digunakan untuk mengetahui bagaimana harian Jawa
Pos Radar Semarang dan Suara Merdeka mengkonstruksikan masing-masing
pasangan calon. Juga untuk mengetahui kecenderungan pemberitaan serta politik
redaksional masing-masing media. Objek penelitian yang dipilih adalah beritaberita
tentang pasangan calon di harian Jawa Pos Radar Semarang dan Suara
Merdeka pada halaman satu dan rubrik khusus selama 26 Maret-22 Juni 2008.
Hasil penelitian menunjukkan bahwa harian Jawa Pos Radar Semarang
berusaha responsif dengan isu-isu politik memberikan konstruksi yang favorable
kepada pasangan Agus Soeyitno-Kholiq Arif, Bibit Waluyo-Rustriningsih dan
HM. Tamzil-Rozaq Rais. Sebaliknya, mereka memberikan konstruksi
unfavorable kepada pasangan Bambang Sadono-M. Adnan dan Sukawi Sutarip-
Sudharto. Sedangkan Suara Merdeka memilih gaya pemberitaan yang aman dan
tidak tendesius kepada masing-masing pasangan calon. Hasilnya, mereka
cenderung mengkonstruksikan pasangan Bambang Sadono-M. Adnan, Bibit
Waluyo-Rustriningsih dan HM. Tamzil-Rozaq Rais dengan bingkai yang
favorable. Sedangkan pasangan Agus Soeyitno-Kholiq Arif dan Sukawi Sutarip-
Sudharto dalam bingkai unfavorable
Unsupervised shape clustering using diffusion map
No full textThe quotient space of all smooth and connected curves represented by a fixed number of boundary points is a finite-dimensional Riemannian manifold, also known as a shape manifold. This makes the preservation of locality a critically important issue when reducing the dimensionality of shapes on the manifold. We present a completely unsupervised clustering algorithm employing diffusion maps for locality-preserving embedding of shapes onto a much lower-dimensional space. The algorithm first obtains a non-linear low-dimensional embedding of shape context features of outer boundary contours of the shapes. Considering the embedded coordinates as a new minimalist representation of shapes, a clustering of shapes is obtained using a finite mixture model. The proposed clustering algorithm is computationally efficient, as it relies on clustering in a very lowdimensional space, and produces much improved results (88.6% for a 7-class dataset) as compared to clustering with conventional linear projections
Labour Market Dynamics in Pakistan: Evidence from the Longitudinal Data
No full textThe bulk of research on labour market conditions in Pakistan has concentrated on the economic activity rate, the number of employed persons, or the unemployment rate at a particular point in time. These stock measures of labour market situation are useful from a policy viewpoint as they give a broad indication of the dimension of the problem. For example, the recent labour force surveys show an increase in the level of open unemployment from 5.9 percent in 1997-98 to 7.8 percent in 1999-2000 [Pakistan (2001)]. There is also an emerging consensus that during the 1990s poverty has increased at the national as well as for rural and urban areas of the country [Qureshi and Arif (2001)]. Labour market is considered as the main route for establishing the link between macro policies, the resulting GDP growth and poverty alleviation [Rahman (2002)]. Interim Poverty Reduction Strategy Paper (IPRSP) and other development plans have suggested various targets of employment creation for poverty reduction. The stock measures of labour market conditions, such as unemployment rate, are considered to be inadequate from the viewpoint of developing appropriate policy responses. There is a need to gain further insights by examining the structure of labour market in terms of its dynamic components: these being the turnover of persons into and out of the labour force and turnover into and out of employment and unemployment pools
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Visual composition of complex queries on an integrative genomic and proteomic data warehouse
No full textBiomedical questions are usually complex and regard several different life science aspects. Numerous valuable and he- terogeneous data are increasingly available to answer such questions. Yet, they are dispersedly stored and difficult to be queried comprehensively. We created a Genomic and Proteomic Data Warehouse (GPDW) that integrates data provided by some of the main bioinformatics databases. It adopts a modular integrated data schema and several metadata to de- scribe the integrated data, their sources and their location in the GPDW. Here, we present the Web application that we developed to enable any user to easily compose queries, although complex, on all data integrated in the GPDW. It is publicly available at http://www.bioinformatics.dei.polimi.it/GPKB/. Through a visual interface, the user is only re- quired to select the types of data to be included in the query and the conditions on their values to be retrieved. Then, the Web application leverages the metadata and modular schema of the GPDW to automatically compose an efficient SQL query, run it on the GPDW and show the extracted requested data, enriched with links to external data sources. Per- formed tests demonstrated efficiency and usability of the developed Web application, and showed its and GPDW re- levance in supporting answering biomedical questions, also difficult
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
Arthroscopically-assisted Reduction and Internal Fixation (ARIF) of tibial plateau fractures: clinical and radiographic medium-term follow-up
No full textBackground and Aim of the work: Tibial plateau fractures include a wide spectrum of lesions with
potentially disabling sequelae. Arthroscopically-assisted Reduction and Internal Fixation (ARIF) is an alternative
to traditional ORIF. The aim of this retrospective single centre study is to evaluate medium-term clinical and
radiographic outcomes achieved in a consecutive series of patients treated with ARIF. Methods: 21 patients, with a
mean age of 52.2 ± 13.4 years at surgery, were included. According to Schatzker classification, there were 9 type II,
10 type III, 2 type IV fractures. Associated intra-articular injuries (meniscal tears, tibial spine fractures, chondral
lesions) were detected in 8 patients. At follow up, patients were clinically and radiographically evaluated according
to knee ROM, KOOS, OKS and Rasmussen Clinical and Radiological Scores. Results: At an average follow-up
of 84 ± 22.5 months, 18 patients were evaluated. Mean values recorded were the following: knee ROM 1° - 135°,
OKS 41.6 / 48 ± 8.18, subscale KOOS scores ranged from 75% ± 25.4 (Quality of Life) to 91.1% ± 11.2 (Pain),
Rasmussen Clinical e Radiological 27.2 ± 2.64 (14 excellent, 3 good, 1 fair) and 9.1 ± 0.64 (15 excellent, 3 good),
respectively. Worse results were observed in 5 patients with pre-existing degenerative chondropathy. Conclusions:
ARIF revealed to be an effective technique for surgical treatment of unicondylar tibial plateau fractures. Our
findings support the favourable results reported by other authors. ARIF is not a simple technique and requires
specific experience in knee arthroscopy and a steep learning curve
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