secondary channel
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2021 ◽  
Vol 5 (5) ◽  
pp. 231-238
Author(s):  
Olanrewaju M Oye ◽  
Lawrence Hart ◽  
Sika Orupabo

Navigation in Lower River Niger is seasonal because of insufficient water depth during the dry season. This is a limitation to economic benefits derivable compared to when the river is navigable throughout the year. Government and stakeholders alike have exerted efforts in the past years to create an unimpeded navigable channel without much success. The need to ensure all-year-round navigation in the Lower River Niger for industrial and commercial purposes necessitated this research work. The main thrust of this work is to determine bathymetric components parameters of the river necessary for the design of an appropriate river training structure to divert river flow from the secondary channel to the main channel. The specific objective hereto is to assess the extent and geometry of the river banks, the configuration of the river bed, the river flow velocity and discharge. The approach deployed in this work is the classical method of acoustic principle premised on Remote Sensing techniques. The shape of the river was obtained through waypoint survey using Garmin eTrex 10 handheld GPS, while the riverbed configuration was determined through bathymetric survey using Odom Echotrack MK III single beam Echo Sounder and the flow velocity data was acquired using Valeport 106 Current Meter. Data processing and analysis were achieved using Garmin Basecamp 4.7.3, Wintopo V7.03, Valeport Datalog X2 and Surfer 13 software. The length of the study area measured along the main channel was obtained as 5.94km while that of secondary channel gave 4.30km. Area occupied by the main channel was found to be 2,636,331.3m2 and 1,759,045.4m2 for the secondary channel. Average depth on the main channel was 0.21m while on the secondary channel was -0.89m, depth figures referred to Lokoja local datum. The average flow velocity was obtained to be 0.449m/s and the cross-sectional area of the river as 1568.75m2, which gave a value of 704.2m3/s for the river discharge. The research produced the digital terrain model (DTM) and bathymetric charts of the study area. The parameters obtained in this study is a useful tool in defining an appropriate embankment dam suitable to divert the flow from the secondary channel to the main channel to enhance depth towards all-season navigation in Lower River Niger.


Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4634
Author(s):  
Kuan-Ying Huang ◽  
Jyh-Ching Juang ◽  
Yung-Fu Tsai ◽  
Chen-Tsung Lin

Multiple frequency global navigation satellite system (GNSS) has become more complex due to the existence of extra channels. Typically, auxiliary methods are used to synchronize the second signals at other bands by aiding the acquired channel parameters. However, there are critical limitations because the reception of GNSS signals is subject to uncertainties due to noise carrier injection or circuit interference. The relationship between the two Doppler frequencies can be affected by uncertainties. Therefore, we aimed to implement an efficient dual-frequency field-programmable gate array (FPGA), performing a direct aid tracking method for the secondary channel to achieve resource efficiency and inner aid robustness. A robust estimator that directly links two loops in the two bands is proposed. In this scheme, (1) a robust estimator able to cope with uncertainty; (2) a primary tracking scheme to obtain the error boundary, and (3) a tracked bit-boundary for the initial code phase of the second channel are used. Based on experiments on the FPGA, the robust channel link can achieve direct aid tracking, and 31.02% of the original hardware resources from the aided acquisition module were released satisfactorily.


2021 ◽  
Vol 5 (3) ◽  
pp. 163-178
Author(s):  
Risky Ramadan ◽  
Budi Indra Setiawan

The most problem that occurs in Cinangka Irrigation Area is the not function of sluice and not used to properly regulate water of it. If the discharge regulator is not operated properly, the provision of irrigation water has the potential to be wasteful or lacking. The purpose of this study is to determine the discharge requirements for secondary irrigation water in Cinangka, produce a design of sluice in the channel and an estimated cost of manufacture. The study was conducted in the Cinangka Irrigation Area, Cibitung Tengah Village, Tenjolaya District, Bogor Regency. The study began from April - June 2020. The results obtained were known to be evapotranspiration, effective rainfall, and irrigation needs in the secondary channel of DI Cinangka per period of irrigation for one year. The largest Eto value occurred in September of 5.8 mm / day, the largest Cheff value occurred in November of 8.4 mm / day and the largest debit of needs occurred in March of 0.6 m3 / sec. Secondary sluice designed  manifold steel sluice with high specification and door width 1x 1 m, total height 2 m door, handlebar diameter 45 cm. Dratstick used is 1.5 inches. Estimated cost for making doors is IDR 7,085,000. These costs can increase depending on the manufacture location and manufacture services.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Hao-Hong Pei ◽  
Tarek Hilal ◽  
Zhuo A. Chen ◽  
Yong-Heng Huang ◽  
Yuan Gao ◽  
...  

AbstractCellular RNA polymerases (RNAPs) can become trapped on DNA or RNA, threatening genome stability and limiting free enzyme pools, but how RNAP recycling into active states is achieved remains elusive. In Bacillus subtilis, the RNAP δ subunit and NTPase HelD have been implicated in RNAP recycling. We structurally analyzed Bacillus subtilis RNAP-δ-HelD complexes. HelD has two long arms: a Gre cleavage factor-like coiled-coil inserts deep into the RNAP secondary channel, dismantling the active site and displacing RNA, while a unique helical protrusion inserts into the main channel, prying the β and β′ subunits apart and, aided by δ, dislodging DNA. RNAP is recycled when, after releasing trapped nucleic acids, HelD dissociates from the enzyme in an ATP-dependent manner. HelD abundance during slow growth and a dimeric (RNAP-δ-HelD)2 structure that resembles hibernating eukaryotic RNAP I suggest that HelD might also modulate active enzyme pools in response to cellular cues.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Llorenç Fernández-Coll ◽  
Katarzyna Potrykus ◽  
Michael Cashel ◽  
Carlos Balsalobre

Abstract There is a growing appreciation for the diverse regulatory consequences of the family of proteins that bind to the secondary channel of E. coli RNA polymerase (RNAP), such as GreA, GreB or DksA. Similar binding sites could suggest a competition between them. GreA is characterised to rescue stalled RNAP complexes due to its antipause activity, but also it is involved in transcription fidelity and proofreading. Here, overexpression of GreA is noted to be lethal independent of its antipause activity. A library of random GreA variants has been used to isolate lethality suppressors to assess important residues for GreA functionality and its interaction with the RNA polymerase. Some mutant defects are inferred to be associated with altered binding competition with DksA, while other variants seem to have antipause activity defects that cannot reverse a GreA-sensitive pause site in a fliC::lacZ reporter system. Surprisingly, apparent binding and cleavage defects are found scattered throughout both the coiled-coil and globular domains. Thus, the coiled-coil of GreA is not just a measuring stick ensuring placement of acidic residues precisely at the catalytic centre but also seems to have binding functions. These lethality suppressor mutants may provide valuable tools for future structural and functional studies.


2020 ◽  
Vol 5 (2) ◽  
pp. 82
Author(s):  
Kartini Sari ◽  
Budiawan Sulaeman

Tujuan khusus penelitian ini untuk menganalisis banyaknya debit air dan efesiensi kebutuhan air pada jaringan irigasi sekunder di Kelurahan Mawa Kecamatan Sendana Kota Palopo. Urgensi penelitian ini, untuk mengetahui efisiensi irigasi dalam melakukan pengukuran dan pengaturan yang tepat sasaran, volume irigasi untuk memenuhi kebutuhan pertumbuhan tanaman. Metode yang digunakan dalam pengukuran debit adalah metode pelampung (apung) dengan Cara mengambil beberapa titik koordinat geografis irigasi untuk pengambilan data, sehingga memberikan data yang akurat dalam pengembangan irigasi di Kelurahan Mawa Kecamatan Sendana kedepan.Hasil penelitian; (1). Jumlah air yang masuk di saluran sekunder hulu sebesar 0.3580 m3/det., dan tiba di titik akhir penelitian sangat kurang yaitu sebesar 0.0985m3/det, dan jika dihitung secara keseluruhan dapat diketahui total jumlah debit airyang masuk pada jaringan irigasi sekunder Mawa yaitu 2,29170436 m3/det. atau setara dengan 2.291.704,36 liter/ha. (2). Efesiensi penggunaan air irigasi jaringan sekunder Mawa sebesar 36%, dan kehilangan air disepanjang saluransebesar 64 %, hal ini menandakan bahwa saluran sekunder Mawa masih belum mencapai standar efesiensi yang diharuskan oleh direktorat jendral pengairan, departemen pekerjaan umum yang dipersyaratkan dalam standar perencanaan irigasi KP-01.The specific purpose of this research is to analyze the amount of water discharge and the efficiency of water needs in secondary irrigation networks in Mawa Village, Sendana District, Palopo City. The urgency of this research is to determine the efficiency of irrigation in measuring and setting the right target of irrigation volume to meet the needs of plant growth. The method used in measuring discharge is the buoy method by taking several geographic coordinates of irrigation as data collection, so as to provide accurate data in the development of irrigation in Mawa Village, Sendana District in the future. The results: (1) The amount of water that enters the upstream secondary channel is 0.3580 m3/s and arrives at the endpoint of the study with a very low amount of water, namely 0.0985 m3/s, and if it is calculated as a whole it can be seen the total amount of water discharge. which is included in the Mawa secondary irrigation network, namely 2.29170436 m3/s or equivalent to 2,291,704.36 liters/ha. (2) The efficiency of the use of Mawa's secondary network irrigation water is 36%, and the water loss along the canal is 64%, this indicates that the Mawa secondary channel still has not reached the efficiency standard required by the Directorate General of Irrigation, under the Ministry of Public Works which is required in irrigation planning standards KP-01


Author(s):  
Silvester Wadan Koten ◽  
Suhudi Suhudi

Drainage means to drain, dispose, or drain water. In general drainage can be defined as a series of water structures that function to reduce or remove excess water from an area or land, so that the land can be used optimally. The purpose of this research is to plan the drainage system of the Istana Safira Dau housing in Malang Regency, which in general is not all planned. Analysis and data management methods used are manual calculations in accordance with the rational method for calculating discharges, and the formula for finding the water level using h SNI for channel discharge. After the calculation, the primary channel dimension is obtained with the base channel width b = 0.50 m and channel depth 0.50 m, secondary channel dimensions are channel width b = 0.40 m and channel depth is 0.40 m, tertiary channel dimensions is channel width = 0.30 m and channel depth 0.30 m with guard height for each channel is 3% of the planned channel depth. Rectangular cross section of a rectangular channel.


2020 ◽  
Author(s):  
Markus Wahl ◽  
Hao-Hong Pei ◽  
Tarek Hilal ◽  
Zhuo Chen ◽  
Yong-Heng Huang ◽  
...  

Abstract Cellular RNA polymerases can become trapped on DNA or RNA, threatening genome stability and limiting free enzyme pools, or enter dormancy. How RNA polymerase recycling into active states is achieved and balanced with quiescence remains elusive. We structurally analyzed Bacillus subtilis RNA polymerase bound to the NTPase HelD. HelD has two long arms: a Gre cleavage factor-like coiled-coil inserts deep into the RNA polymerase secondary channel, dismantling the active site and displacing RNA; a unique helical protrusion inserts into the main channel, prying β and β’ subunits apart and dislodging DNA, aided by the δ subunit. HelD release depends on ATP, and a dimeric structure resembling hibernating RNA polymerase I suggests that HelD can induce dormancy at low energy levels. Our results reveal an ingenious mechanism by which active RNA polymerase pools are adjusted in response to the nutritional state.


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