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Journal articles on the topic 'Turbulent rejim'

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1

Bindar, Yazid, and Rusdi Wijisaksono. "Karakterisisasi lapisan film jatuh (FLF) pada dinding dalam tabung vertikal oleh pengumpan pusar secara eksperimen dan simulasi CFD." Jurnal Teknik Kimia Indonesia 5, no. 3 (2018): 468. http://dx.doi.org/10.5614/jtki.2006.5.3.2.

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Falling liquid film characterization in the inside wall of vertical tube using whirl feeder through experiment and CFD simulationFalling Liquid Film (FLF) from swirl feed holes were characterized through experiment and Computational Fluid Dynamic (CFD) simulation. The falling liquid film is quantified by its thickness. The effect of liquid flow rate, physical properties and diameter of swirl holes are successfully correlated to form a model that is based on the liquid film theory. The FLF dimensionless thickness linearly relates to power functions of Reynolds and Galilea numbers. The minimum m
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2

Fəhmin Əzizli, Elnur Əlizadə, Mehparə Adıgözəlova, Fəhmin Əzizli, Elnur Əlizadə, Mehparə Adıgözəlova. "LABORATORIYA ŞƏRAITINDƏ YÜKSƏKPARAFINLI NEFTIN REOLOJI XASSƏLƏRININ TƏDQIQI." PAHTEI-Procedings of Azerbaijan High Technical Educational Institutions 18, no. 07 (2022): 64–68. http://dx.doi.org/10.36962/pahtei18072022-64.

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Sanqaçal yatağının nefti yüksək özlüdür, yüksək miqdarda parafin və qatranlara malikdir, bununla əlaqədar olaraq hasilat zamanı APQÇ-nin əmələ gəlməsində və neft-mədən avadanlıqlarında intensiv toplanmasında problemlər yaranır. Bundan əlavə, bu neft, əsasən, magistral kəmər vasitəsilə nəql olunur.Səmərəli nəqli üçün reoloji parametrlərin müəyyən göstəricilərinə riayət etmək lazımdır. İşdə qarşıya qoyulan problemləri həll etmək üçün biz Sanqaçal yataqlarından hasil olunan neftin reoloji xassələrinin laboratoriya tədqiqatları kompleksini həyata keçirdik. Sınaqlar aparıldı və depressiv, antiturbu
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3

Qafar Ismayılov, Fidan Ismayılova, Qafar Ismayılov, Fidan Ismayılova, and Əmrah Qulubəyli Əmrah Qulubəyli. "LAMİNAR REJİMDƏ MAYENİN HƏRƏKƏTİ VƏ SIXIŞDIRILMASININ REOTEXNOLOJİ XÜSUSİYYƏTLƏRİ." PAHTEI-Procedings of Azerbaijan High Technical Educational Institutions 37, no. 02 (2024): 379–87. http://dx.doi.org/10.36962/pahtei37022024-379.

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Müxtəlif reoloji xüsusiyyətlərə malik olan neftlərin, neft məhsullarının, texnoloji mayelərin, qazma məhlulları və sement məhlullarının, borularda laminar hərəkət rejimləri neft-mədən praktikasında geniş yayılmış hərəkət formasıdır. Turbulent axınlarla müqayisədə nisbətən sadə hərəkət forması hesab edilməsinə baxmayaraq tədqiqatlar göstərir ki, laminar axınlrda sürət sürət profilinin stabilləşməsi üçün tələb olunan zonanın uzunluğu turbulent axınlarla müqayisədə dəfələrlə çoxdur [1÷4]. Bu cür stabilləşmə zonalarının mövcudluğu laminar axınların hidrodinamik stabilləşmə zonalarının düzgün qiymə
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4

Yu, C., and U. Maas. "Implementation of the Scalar Dissipation Rate in the REDIM Concept and its Validation for the Piloted Non-Premixed Turbulent Jet Flames." Eurasian Chemico-Technological Journal 23, no. 3 (2021): 169. http://dx.doi.org/10.18321/ectj1100.

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In order to address the impact of the concentration gradients on the chemistry – turbulence interaction in turbulent flames, the REDIM reduced chemistry is constructed incorporating the scalar dissipation rate, which is a key quantity describing the turbulent mixing process. This is achieved by providing a variable gradient estimate in the REDIM evolution equation. In such case, the REDIM reduced chemistry is tabulated as a function of the reduced coordinates and the scalar dissipation rate as an additional progress variable. The constructed REDIM is based on a detailed transport model includi
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Rumaherang, Edwina Jerusalem, W. M. E. Wattimena, Sesilia M. Rawulun, and Excelsis Noya. "STUDI REGIM ALIRAN FLUIDA DAN PENENTUAN HEAD LOSS AKIBAT GESEKAN PADA INSTALASI PERPIPAAN." ALE Proceeding 6 (October 31, 2023): 154–61. http://dx.doi.org/10.30598/ale.6.2023.154-161.

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Instalasi perpipaan dalam industry merupakan sistem keteknikan memegang perananan penting yang berfungsi untuk mengalirkan air, minyak dan gas dari satu titik ke titik lain melalui semua komponen yang tercakup didalamnya. Sistem perpipaan terdiri dari pipa lurus, sambungan-sambungan, belokan katup-katup dan peralatan-peralatan instrumentasi yang harus bekerja secara optimal. Regim aliran fluida di dalam berbagai komponen perpipaan memberikan pengaruh terhadap aliran teristimewa pada dua parameter penting yaitu koefesien gesek dan kehilangan head. Tujuan penelitian ini adalah memantau sifat per
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6

Askarov, X., and S. Asqarova. "ISSIQLIK ALMASHTIRGICHLARDA JARAYONLARNI JADALLASHTIRISH USULLARI." GOLDEN BRAIN 1, no. 2 (2023): 21–23. https://doi.org/10.5281/zenodo.7555231.

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<em>U</em><em>shbu maqolada i</em><em>ssiqlik&nbsp; almashinuv qurilmalari</em><em>ning issiqlik almashinuvida yuzaga keluvchi kamchiliklar, qatlam xosil b</em><em>o&lsquo;</em><em>lishi quvurlarning issiqlil almashinuvini yaxshilashga qaratilgan yechim va tahlillar natijasida </em><em>intensivlashtirish</em><em> usullari keltirilgan.</em>
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7

Umurani, Khairul, and Arya Rudi Nasution. "Analisa numerik pengaruh diameter perforate terhadap perpindahan panas dan penurunan tekanan pada saluran segi empat 4:1 menggunakan perforated groove v- rib." Jurnal Teknik Mesin Indonesia 17, no. 2 (2022): 12–20. http://dx.doi.org/10.36289/jtmi.v17i2.299.

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Dalam saluran pendingin internal bilah turbin gas, struktur rusuk banyak digunakan untuk meningkatkan perpindahan panas konveksi dengan aliran pendingin yang melewati permukaan rusuk. Kajian ini berkonsentrasi pada V-rib berlubang dengan alur pada saluran pendingin dengan penampang persegi panjang. Kajian ini menganalisis perpindahan panas dan penurunan tekanan pada saluran segi empat dengan alur v-rib berlubang untuk memberikan solusi pendingin sudu turbin gas. Kajian ini dilakukan dengan analisis numerik. Beberapa model dibuat dan dianalisis menggunakan Solidworks Flow Simulation, sebuah kom
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8

Yu, Chunkan, Felipe Minuzzi, and Ulrich Maas. "Numerical Simulation of Turbulent Flames based on a Hybrid RANS/Transported-PDF Method and REDIM Method." Eurasian Chemico-Technological Journal 20, no. 1 (2018): 23. http://dx.doi.org/10.18321/ectj705.

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A hybrid RANS/Transported-PDF model for the simulation of turbulent reacting flows based on automatically reduced mechanisms for the chemical kinetics (reaction-diffusion manifold, REDIM) is presented in this work. For modelling of turbulent reacting flows, chemistry is a key problem and affects largely the accuracy. The PDF method has been widely used since the chemical source term is in a closed form, without any modelling. Despite of this advantage of PDF method, detailed chemical kinetics is not desired due to its heavy computational effort. From this aspect, the detailed chemical kinetics
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9

Zeng, Haixiang, Ping Wang, Qian Yu, Meenatchidevi Murugesan, Linsong Jiang, and Prashant Shrotriya. "Direct numerical simulation of triple flames by using 2D reaction-diffusion manifold tabulation method." Thermal Science, no. 00 (2020): 198. http://dx.doi.org/10.2298/tsci190909198z.

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The characteristics of partially-premixed flames is investigated by simulating a series of triple flames with different variations of chemical equivalent ratio. A two-dimensional Reaction-Diffusion Manifold (REDIM) chemistry tabulation method is employed in the simulation and the results are compared with the methane-air 19-step chemical reaction mechanism. The performance of these two mechanisms is then assessed by using direct numerical simulations coupled with GRI3.0 detailed mechanism. It is shown that both 2D REDIM table and 19-step simplified mechanism can describe the temperature and ma
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10

Umurani, K., M. Muharnif, and A. M. Siregar. "Analisa Numerik Pengaruh Diameter Lubang Berperforasi Rusuk V Terhadap Penurunan Tekanan Pada Saluran Segiempat." Jurnal MESIL (Mesin Elektro Sipil) 2, no. 1 (2021): 54–65. http://dx.doi.org/10.53695/jm.v2i1.249.

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Dalam saluran pendingin internal pada sudu turbin gas, struktur rusuk banyak digunakan untuk menambah perpindahan panas konvektif dengan aliran fluida pendingin yang melewati permukaan berusuk. Penelitian ini berkonsentrasi pada rusuk V berperforasi dengan lubang lurus pada saluran pendingin dengan penampang persegi panjang, yang bertujuan untuk mengetahui karaketristik perpindahan panas dan penurunan tekanan pada saluran segiempat dengan rusuk V berperforasi. Penelitian ini dilakukan secara analisa numerik dengan model k-? digunakan dalam studi numerik untuk simulasi medan aliran. Saluran uji
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11

Boy Anugerah and Jabinson Purba. "Kondisi Politik dan Keamanan Afghanistan di Bawah Rezim Taliban dan Signifikansinya terhadap Geopolitik Global." Jurnal Lemhannas RI 9, no. 3 (2021): 13–34. http://dx.doi.org/10.55960/jlri.v9i3.399.

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Kebijakan Amerika Serikat di bawah Presiden Joe Biden untuk menarik seluruh pasukan Amerika Serikat di Afghanistan paling lambat 11 September 2021 menimbulkan turbulensi politik dan keamanan di level domestik Afghanistan. Pemerintahan Afghanistan yang dibentuk Amerika Serikat di bawah rezim Presiden Ashraf Ghani kolaps digantikan oleh rezim Taliban yang berkuasa sejak pertengahan Agustus 2021 yang lalu. Kembalinya Taliban sebagai rezim berkuasa di Afghanistan menimbulkan signifikansi politik dan keamanan, tidak hanya di internal Afghanistan, tapi juga bagi geopolitik global. Tulisan ini bertuj
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12

Fischer, Simon, Detlev Markus, Asghar Ghorbani, and Ulrich Maas. "PDF Simulations of the Ignition of Hydrogen/Air, Ethylene/Air and Propane/Air Mixtures by Hot Transient Jets." Zeitschrift für Physikalische Chemie 231, no. 10 (2017): 1773–96. http://dx.doi.org/10.1515/zpch-2016-0904.

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AbstractA numerical investigation is carried out to study ignition events of different premixed stoichiometric fuel/air mixtures by hot exhaust gas jets. The simulations are performed for premixed, stoichiometric hydrogen/air, ethylene/air and propane/air mixtures in configurations relevant to safety applications. The ignition events of the different fuel/air mixtures by their corresponding exhaust gas jet are examined qualitatively analyzing processes and conditions leading to ignition. A stand-alone probability density function (PDF) method in connection with a projection method (PM) to calc
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13

Wang, Ping, Tian-zeng Hou, Cai-jun Wang, Gerd Steinhilber, and Ulrich Maas. "Large Eddy Simulations of the Darmstadt Turbulent Stratified Flames with REDIM Reduced Kinetics." Flow, Turbulence and Combustion 101, no. 1 (2018): 219–45. http://dx.doi.org/10.1007/s10494-018-9899-1.

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14

Minuzzi, Felipe, Chunkan Yu, and Ulrich Maas. "Simulation of methane/air non-premixed turbulent flames based on REDIM simplified chemistry." Flow, Turbulence and Combustion 103, no. 4 (2019): 963–84. http://dx.doi.org/10.1007/s10494-019-00059-3.

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15

Corneliu, BERBENTE. "Fluid Dynamics in Turbulent Regime (Dinamica Fluidelor in regim Turbulent) Virgiliu N. CONSTANTINESCU, Sterian DANAILA, Stelian GALETUSE (in Romanian) Publishing House of the Romanian Academy, 2008." INCAS BULLETIN 3, no. 3 (2011): 159–60. http://dx.doi.org/10.13111/2066-8201.2011.3.3.17.

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16

Ghorbani, A., G. Steinhilber, D. Markus, and U. Maas. "Ignition by transient hot turbulent jets: An investigation of ignition mechanisms by means of a PDF/REDIM method." Proceedings of the Combustion Institute 35, no. 2 (2015): 2191–98. http://dx.doi.org/10.1016/j.proci.2014.06.104.

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17

Žic, Elvis, and Matija Pilat. "Računalna dinamika fluida i metode vizualizacije strujanja fluida." Zbornik radova 24, no. 1 (2021): 81–101. http://dx.doi.org/10.32762/zr.24.1.5.

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U ovom radu obrađena je tematika primjene i svrhe Računalne dinamike fluida (RDF) u svakodnevnoj praksi te metode vizualizacije strujanja fluida. Radi lakšeg shvaćanja pojma modela turbulencije u radu su navedene osnovne karakteristike fluida od kojih je fokus dan na viskoznosti i kompresibilnosti. U svrhu opisa dinamike gibanja fluida definirane su osnovne vladajuće jednadžbe strujanja fluida, koje uključuju laminarani i turbulentni režim toka. Značajan fokus ovog rada posvećen je kreiranju numeričkih modela primjenom Računalne dinamike fluida, od samog predprocesiranja, definiranja domene pr
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18

Shrotriya, Prashant, Ping Wang, Linsong Jiang, and Meenatchidevi Murugesan. "REDIM-PFDF modelling of turbulent partially-premixed flame with inhomogeneous inlets using top-hat function for multi-stream mixing problem." Aerospace Science and Technology 107 (December 2020): 106258. http://dx.doi.org/10.1016/j.ast.2020.106258.

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Roekaerts, Dirk J. E. M., B. Merci, and Ulrich Maas. "Elimination of Fast Modes in the Coupled Process of Chemistry and Diffusion in Turbulent Nonpremixed Flames: An Application of the REDIM Approach." International Journal for Multiscale Computational Engineering 7, no. 6 (2009): 487–508. http://dx.doi.org/10.1615/intjmultcompeng.v7.i6.20.

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20

Yu, Chunkan, Paola Breda, Felipe Minuzzi, Michael Pfitzner, and Ulrich Maas. "A novel model for incorporation of differential diffusion effects in PDF simulations of non-premixed turbulent flames based on reaction-diffusion manifolds (REDIM)." Physics of Fluids 33, no. 2 (2021): 025110. http://dx.doi.org/10.1063/5.0039160.

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Burdah, Ibnu. "Morocco protest movements in the post-constitutional reform." Indonesian Journal of Islam and Muslim Societies 7, no. 2 (2017): 201. http://dx.doi.org/10.18326/ijims.v7i2.201-219.

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dth: 0px; "&gt; The research describes and explains the wave of protest movement in theKingdom of Morocco, one of the Muslim countries in the Western Arab, in the post-2011 constitutional referendum. The constitutional reform was carried out as a response to the large and massive people protest. Unlike the cases in other neighboring states where “Arab Spring” took place, the Moroccan movement receded without neither the fall of the regime nor massive casualties. However, intense protest kept taking place, especially in Muhammad V Street leading to the Parliament Building. Some interesting ques
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Mirzə Dadaş-Zadə, Aytən Nəbiyeva, Mirzə Dadaş-Zadə, Aytən Nəbiyeva. "İKIFAZALI SISTEMLƏRIN HIDRODINAMIKASININ ƏSASLARI." PAHTEI-Procedings of Azerbaijan High Technical Educational Institutions 50, no. 03 (2025): 258–63. https://doi.org/10.36962/pahtei50032025-258.

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Təqdim olunan məqalədə, düz borularda qaz-maye axınının təzyiq itkisi və axın xüsusiyyətlərinin hesablanmasında mövcud metodların etibarlılığı və effektivliyi araşdırılmışdır. Ədəbiyyatda və praktika da istifadə olunan ümumiyyətlə qəbul edilmiş metodlar, Reynolds sayına əsaslanır və mayenin özlülük və sıxlığını, daxili boru sürtünmə əmsalını, boru geometrisini və neft dövriyyə sürətini nəzərə alır. Lakin, bu yanaşma yalnız nominal özlülük və sıxlıq dəyərlərini istifadə edir ki, bu da real şəraitlə əhəmiyyətli fərqlər yaradır və təzyiq itkisini qeyri-dəqiq hesablamalara səbəb olur. Eyni zamanda
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23

Caillosse, Jacques. "Reflections on the evolution of public service in French law." Zbornik radova Pravnog fakulteta u Splitu 54, no. 1 (2017): 55–76. http://dx.doi.org/10.31141/zrpfs.2017.54.123.055.

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1.- Ovo izlaganje sadrži (kratki) prikaz ažuriranog stanja klasičnog pitanja: razvoja francuskog prava javne službe. Kroz ovu temu ćemo propitivati promjene koje su utjecale i nastavljaju utjecati na upravno pravo. Ne samo da se upravno pravo može svesti na pravo javne službe, već i, kao što iskustvo pokazuje, promjene koje doživljava javna služba – njezin koncept i pravni režim – imaju veliki utjecaj na sveobuhvatni sustav odnosa koje uprava ima sa „svojim“ pravom. U prilog toj tezi, ponudit ćemo dvostruku demonstraciju. 2.- Prva predstavlja razmišljanje (nužno kratko) o mjestu koje zauzima j
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24

Rombebunga, Yunarto. "Pengaruh Kemiringan Struktur Plat Segitiga Terhadap Kecepatan Gesek Dasar pada Saluran Terbuka." Jurnal Penelitian Enjiniring 25, no. 1 (2022): 37–47. http://dx.doi.org/10.25042/jpe.052021.05.

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Pada aliran saluran terbuka, distribusi kecepatan seringkali dibedakan sebagai distribusi kecepatan di daerah inner region, yang berada di dekat dasar dimana distribusi kecepatan logaritmik berlaku, dan di daerah outer region, yang berada jauh dari dasar dimana distribusi kecepatan menyimpang secara jelas dan sistimatik terhadap hukum logaritmik. Tujuan penelitian adalah struktur mampu meredam energi aliran dasar sehingga kecepatan yang terjadi dapat diminimalisir. Percobaan dilakukan pada saluran flume dengan Panjang 8,00 m, lebar 0,40 m dan tinggi 0,40 m. Untuk kemiringan saluran yang diguna
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Breda, Paola, Chunkan Yu, Ulrich Maas, and Michael Pfitzner. "Validation of an Eulerian Stochastic Fields Solver Coupled with Reaction–Diffusion Manifolds on LES of Methane/Air Non-premixed Flames." Flow, Turbulence and Combustion, December 11, 2020. http://dx.doi.org/10.1007/s10494-020-00235-w.

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AbstractThe Eulerian stochastic fields (ESF) combustion model can be used in LES in order to evaluate the filtered density function to describe the process of turbulence–chemistry interaction. The method is typically computationally expensive, especially if detailed chemistry mechanisms involving hydrocarbons are used. In this work, expensive computations are avoided by coupling the ESF solver with a reduced chemistry model. The reaction–diffusion manifold (REDIM) is chosen for this purpose, consisting of a passive scalar and a suitable reaction progress variable. The latter allows the use of
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Shrotriya, Prashant, Ping Wang, Linsong Jiang, and Meenatchidevi Murugesan. "REDIM-PFDF Sub-grid Scale Combustion Modeling for Turbulent Partially-premixed Flame: Assessment of Combustion Modes." Combustion Science and Technology, June 23, 2020, 1–23. http://dx.doi.org/10.1080/00102202.2020.1782391.

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Piroozian, Ali, and Issham Ismail. "Cuttings Transport In Horizontal And Highly Deviated Wellbores." Jurnal Teknologi, December 13, 2011, 1–14. http://dx.doi.org/10.11113/jt.v56.50.

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Lencongan dari laluan tegak menyebabkan rincisan gerudi berkumpul pada bahagian bawah lubang telaga sehingga terbentuknya lapisan rincisan. Akibatnya, berlaku beberapa permasalahan operasi ketika berlangsungnya penggerudian. Daya seret dan kilas yang melampau, kesukaran yang dialami ketika penyorongan rentetan selongsong ke dalam lubang telaga, kesukaran untuk memperoleh operasi penyimenan yang baik, dan lekatan mekanikal paip gerudi adalah antara beberapa contoh lazim yang berkaitan dengan permasalahan terbabit. Sehubungan itu, pemahaman yang baik tentang parameter utama operasi yang mempenga
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"MIGRACIJE IN VARNOST NA STARI CELINI." CONTEMPORARY MILITARY CHALLENGES, VOLUME 2017 ISSUE 19/3 (September 15, 2017): 7–9. http://dx.doi.org/10.33179/bsv.99.svi.11.cmc.19.3.0.

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Dve leti mineva od evropske migrantske krize. Jeseni 2015 je Evropo preplavil begunski val, kakršnega nismo pričakovali in si ga nismo znali predstavljati. Presenetil nas je v vseh pogledih. Sodobna tehnologija, ugledne ustanove in vodilni svetovni strokovnjaki z različnih področij niso predvideli tega, kar se je zgodilo. Evropski pravni red, človekove pravice, schengenski režim in ideje Zahoda, ki so se hitro razblinile, nam pa je ostala samo gola realnost. Kje so begunci zdaj, koliko jih je in kako se počutijo? Kako je begunska kriza vplivala na nacionalnovarnostni sistem, na skupno evropsko
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