complex block
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2021 ◽  
Vol 2129 (1) ◽  
pp. 012060
Author(s):  
Muhammad Danial Ikmal bin Rusman ◽  
Haslina Abdullah ◽  
Mohamad Shukri Zakaria ◽  
Norfazillah Talib ◽  
Lee Woon Kiow ◽  
...  

Abstract The lower machining time is important characteristic in the drilling machining process. Drilling process costs will increase if the machining time is high. Therefore, the main objective of this research is to develop Ant Colony Algorithm (ACO) to reduce the machining time by obtain the optimal tool path length. By using this algorithm, it can minimize the tool path length and significantly decreasing the machining time of drilling process. Simulating in 3-dimensional drilling on ACO has been constructed to minimize the shortest path of the drilling process. There are two type of workpiece has been used, which is simple block with 10 holes and complex block design that has 154 holes. ACO algorithm has been developed in Matlab R2017b to determine the optimal parameters of ACO of tool path length in drilling. Besides, simulation also has been done to investigate the effect of ACO parameter which is weight of pheromone (α), weight of trail (β), evaporation coefficient (e), and number of iterations. As a result, by define the parameter of iteration number at 900, the optimum parameter of weight of pheromone (α) is 5, weight of trail (β) is 4 and evaporation coefficient (e) is 0.4. Based on these parameters, the minimal tool path length obtain for simple and complex model are 286.965 mm and 6770.9860 mm respectively. Then, the result of tool path length of ACO simulation has been compared with the Mastercam outcome. ACO achieves a total tool path length of 286.965 mm while Mastercam achieved 569.878 mm for simple block design. Meanwhile, for complex block design, ACO produces a total tool path length of 6770.9860 mm while Mastercam has generate 55828.9050 mm of tool path length. By comparing these two approaches, ACO and Mastercam, ACO has that the short total tool path length by 49.64% on simple block design and 87.87% for complex block design.


Author(s):  
Yaroslav V. Shkorbotun

Introduction: Cysts of the maxillary sinuses are found in about 10% of the population. There is a necessity to clarify indications for cyst removal taking into account its size. The purpose of the study to clarify the indications for surgical treatment of maxillary sinus cysts as a risk factor for sinus drainage disorders in the development of maxillary sinusitis. Methods and materials: 57 people (92 sinuses) were examined. There were 20 patients (40 sinuses) with acute rhinosinusitis, 22 patients (22 sinuses) with post-augmentation sinusitis, and 15 (30 sinuses) almost healthy individuals among them. Prediction of the cyst size, which can lead to blockage of the maxillary sinus ostium, was performed by direct measurement on coronary sections at the ostiomeatal complex level distance from the surface of the mucoperiosteum in the area of the alveolar recessus to the lower surface of the mucosal surface in the area of the ostium. The obtained data were verified by calculation method taking into account the height of the sinus at the level of the osteomeatal complex, the magnitude of possible mucoperiosteum edema in the alveolar recessus and ostium in acute rhinosinusitis and post-augmentation sinusitis, as well as the magnitude of mucoperiosteum elevation due to sinus lift. Results: It was found that the vertical size of the cyst, which can potentially lead to blockage of the maxillary sinus ostium in acute rhinosinusitis is 21.2±0.8 mm, 14.7±1.1 mm in sinusitis after augmentation of the maxilla, and 28.5±0.7 mm in practically healthy individuals. The calculated values are 18.5 mm, 14.0 mm and 24.5 mm, respectively. In case of acute rhinosinusitis, the distance from the apex of the cyst to the surface of the mucous membrane of the ostiomeatal complex area may decrease by 12.8 mm, and in sinusitis after sinus lift it may decrease by 20.4 mm. Conclusions: To assess the potential of the ostiomeatal complex block by a cyst located in the alveolar recessus in acute rhinosinusitis, its vertical size is really important according to coronary sections of at the ostiomeatal complex level corresponding to the location of 5-6 teeth of the upper jaw. The indication for removal of the cyst of the alveolar recessus of the maxillary sinus, as a factor that may worsen the course of acute rhinosinusitis due to the anastomosis block, is its size exceeding 20 mm, and 15 mm for patients who plan to sinus lift.


Geosciences ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 271
Author(s):  
Jennifer N. Gifford ◽  
Shawn J. Malone ◽  
Paul A. Mueller

The accretion of the Wyoming, Hearne, and Superior Provinces to form the Archean core of western Laurentia occurred rapidly in the Paleoproterozoic. Missing from Hoffman’s (1988) original rapid aggregation model was the Medicine Hat block (MHB). The MHB is a structurally distinct, complex block of Precambrian crystalline crust located between the Archean Wyoming Craton and the Archean Hearne Province and overlain by an extensive Phanerozoic cover. It is distinguished on the basis of geophysical evidence and limited geochemical data from crustal xenoliths and drill core. New U-Pb ages and Lu-Hf data from zircons reveal protolith crystallization ages from 2.50 to 3.28 Ga, magmatism/metamorphism at 1.76 to 1.81 Ga, and εHfT values from −23.3 to 8.5 in the Archean and Proterozoic rocks of the MHB. These data suggest that the MHB played a pivotal role in the complex assembly of western Laurentia in the Paleoproterozoic as a conjugate or extension to the Montana Metasedimentary Terrane (MMT) of the northwestern Wyoming Province. This MMT–MHB connection likely existed in the Mesoarchean, but it was broken sometime during the earliest Paleoproterozoic with the formation and closure of a small ocean basin. Closure of the ocean led to formation of the Little Belt arc along the southern margin of the MHB beginning at approximately 1.9 Ga. The MHB and MMT re-joined at this time as they amalgamated into the supercontinent Laurentia during the Great Falls orogeny (1.7–1.9 Ga), which formed the Great Falls tectonic zone (GFTZ). The GFTZ developed in the same timeframe as the better-known Trans-Hudson orogen to the east that marks the merger of the Wyoming, Hearne, and Superior Provinces, which along with the MHB, formed the Archean core of western Laurentia.


Electronics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 644 ◽  
Author(s):  
Cheonshik Kim ◽  
Ching-Nung Yang ◽  
Lu Leng

We present a new data hiding method based on Adaptive BTC Edge Quantization (ABTC-EQ) using an optimal pixel adjustment process (OPAP) to optimize two quantization levels. The reason we choose ABTC-EQ as a cover media is that it is superior to AMBTC in maintaining a high-quality image after encoding is executed. ABTC-EQ is represented by a form of t r i o ( Q 1 , Q 2 , [ Q 3 ] , BM) where Q is quantization levels ( Q 1 ≤ Q 2 ≤ Q 3 ) , and BM is a bitmap). The number of quantization levels are two or three, depending on whether the cover image has an edge or not. Before embedding secret bits in every block, we categorize every block into smooth block or complex block by a threshold. In case a block size is 4x4, the sixteen secret bits are replaced by a bitmap of the smooth block for embedding a message directly. On the other hand, OPAP method conceals 1 bit into LSB and 2LSB respectively, and maintains the quality of an image as a way of minimizing the errors which occur in the embedding procedure. The sufficient experimental results demonsrate that the performance of our proposed scheme is satisfactory in terms of the embedding capacity and quality of an image.


2020 ◽  
Vol 8 (2) ◽  
pp. 101-113
Author(s):  
Valeriy V. Markin ◽  
Aleksandr V. Kinsburskiy

The increasing complexity of modern social life gives rise to multilateral contradictions between various social actors on a whole range of interests and values. Such ripened and formed contradictions can turn into a very acute complex conflict, one of the varieties of which is a block conflict, where there is no obvious dominant, but the “main line” of the confrontation of several parties, along which others are involved, is traced. Such conflicts, as a rule, have a long process and are difficult for their optimal resolution. On the example of a protracted regional conflict of a socio-economic, environmental and ethnocultural order around the shihan (mountain) of Tratau in Bashkortostan, which received a certain socio-political discourse, the article reveals its complex (block) nature, search (including through sociological research) and finding a compromise solution to resolve it. Methodological approaches, a methodological and instrumental apparatus of sociological support for the search, preparation and adoption of political and managerial decisions regarding the specified regional complex (block) conflict are shown.


2019 ◽  
Vol 19 (12) ◽  
pp. 04019127
Author(s):  
Xiaodong Fu ◽  
Qian Sheng ◽  
Liwei Wang ◽  
Jian Chen ◽  
Zhenping Zhang ◽  
...  

2019 ◽  
Vol 97 (8) ◽  
pp. 3415-3425 ◽  
Author(s):  
Ruqing Zhong ◽  
Olayiwola Adeola

Abstract The energy values of solvent-extracted canola meal (SECM) and expeller-derived canola meal (EDCM) for broiler chickens and growing pigs were determined in 2 experiments using the regression method. Corn–soybean meal reference diet (RF) and 4 test diets were prepared. The test diets consisted of SECM or EDCM that partly replaced the energy sources in the RF at 100 or 200 g/kg, respectively. The ratios of all energy ingredients were kept similar across all experimental diets. In Exp. 1, a total of 300 birds were fed standard broiler starter diet from days 0 to 19 posthatching. On day 19, 240 birds (776 ± 79.3 g initial BW) were assigned into 5 experimental diets in a randomized complex block design with BW as a blocking factor. Excreta were collected from days 23 to 25 and ileal digesta were collected after birds were euthanized by CO2 asphyxiation on day 26. In Exp. 2, 40 barrows (28.4 ± 1.6 kg initial BW) were allotted to 5 experimental diets according to the randomized complete block design with BW as a blocking factor. After 5-d adaption period, the feces and urine samples were collected for 5 d by total collection method. The ileal digestible energy (IDE), apparent ME (AME), and nitrogen-corrected apparent ME (AMEn) in Exp. 1 and the DE, AME, and AMEn in Exp. 2 for experimental diets and canola meals were determined. In Exp. 1, the inclusion of canola meals to RF linearly decreased the IDE, AME, and AMEn for birds fed SECM diets (P < 0.01) and the AME and AMEn for birds fed EDCM diets (P < 0.01). Furthermore, quadratic effects were also found in the IDE, AME, and AMEn by the inclusion of EDCM to RF (P < 0.05). The IDE were 2,194 and 3,514 kcal/kg DM for SECM and EDCM in broiler chickens, respectively. The respective ME and MEn values were 1,919 and 1,695 kcal/kg DM for SECM and 3,134 and 2,937 kcal/kg DM for EDCM. In Exp. 2, the SECM or EDCM addition to RF linearly decreased the AME and AMEn for pigs (P < 0.01). The DE content was also decreased linearly with the increasing level of SECM (P < 0.01). The DE, ME, and MEn of SECM for pigs were 3,109, 2,891, and 2,655 kcal/kg DM, respectively. The EDCM contained 3,850 kcal of DE, 3,581 kcal of ME, and 3,491 kcal of MEn/kg DM for pigs. In conclusion, the energy values of EDCM are greater than those of SECM for broiler chickens and pigs, and pigs utilize more of the GE in SECM and EDCM than broiler chickens.


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