1) ROTI (Rate of Turn Indicator) is an instrument that assists ship officers in planning, executing, and monitoring a vessel's progress along curved segments of its charted course. It indicates the rate of turn (in degrees per minute) to port or starboard.
2) For large vessels, turns must be executed along curved paths rather than sharp corners due to momentum and water friction. ROTI helps determine the radius and rate of turn needed based on factors like vessel size and speed.
3) There are two main turn types - constant radius, where the radius remains fixed and rate of turn varies, and constant rate, where the rate of turn remains fixed and the radius varies. The document provides
Mooring and Unmooring operation during berthing and un-berthing of vessel is critical. The cadets are weak links in the team till they gain some experience. This presentation would help cadets to understand ,appreciate hazards and consequences. They can do spot risk assessment based on learning from presentation. Hope this presentation will help in reducing accidents arising from Mooring Ops.
Thanks for watching the slides ,await for your inputs.
Capt. Vivek Trivedi
smrviv@yahoo.co.in
Provides information needed by Sea Scouts to explain and demonstrate US Power Squadron plotting & labeling standards, in coordination with the deck log, using more restrictive Ship 378 standards.
Mooring and Unmooring operation during berthing and un-berthing of vessel is critical. The cadets are weak links in the team till they gain some experience. This presentation would help cadets to understand ,appreciate hazards and consequences. They can do spot risk assessment based on learning from presentation. Hope this presentation will help in reducing accidents arising from Mooring Ops.
Thanks for watching the slides ,await for your inputs.
Capt. Vivek Trivedi
smrviv@yahoo.co.in
Provides information needed by Sea Scouts to explain and demonstrate US Power Squadron plotting & labeling standards, in coordination with the deck log, using more restrictive Ship 378 standards.
The U.S. Coast Guard Auxiliary’s Weekend Navigation Course is a comprehensive course designed for both experienced and novice powerboat and sailboat operators. The course is divided into two major parts designed to educate the boating enthusiast in skills required for a safe voyage on a variety of waters and boating conditions. This course can be taught as a whole or as separate modules.
The U.S. Coast Guard Auxiliary’s Weekend Navigation Course is a comprehensive course designed for both experienced and novice powerboat and sailboat operators. The course is divided into two major parts designed to educate the boating enthusiast in skills required for a safe voyage on a variety of waters and boating conditions. This course can be taught as a whole or as separate modules.
Each month, join us as we highlight and discuss hot topics ranging from the future of higher education to wearable technology, best productivity hacks and secrets to hiring top talent. Upload your SlideShares, and share your expertise with the world!
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Salas, V. (2024) "John of St. Thomas (Poinsot) on the Science of Sacred Theol...Studia Poinsotiana
I Introduction
II Subalternation and Theology
III Theology and Dogmatic Declarations
IV The Mixed Principles of Theology
V Virtual Revelation: The Unity of Theology
VI Theology as a Natural Science
VII Theology’s Certitude
VIII Conclusion
Notes
Bibliography
All the contents are fully attributable to the author, Doctor Victor Salas. Should you wish to get this text republished, get in touch with the author or the editorial committee of the Studia Poinsotiana. Insofar as possible, we will be happy to broker your contact.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
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Heavy metals are naturally occuring metallic chemical elements that have relatively high density, and are toxic at even low concentrations. All toxic metals are termed as heavy metals irrespective of their atomic mass and density, eg. arsenic, lead, mercury, cadmium, thallium, chromium, etc.
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Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
ISI 2024: Application Form (Extended), Exam Date (Out), EligibilitySciAstra
The Indian Statistical Institute (ISI) has extended its application deadline for 2024 admissions to April 2. Known for its excellence in statistics and related fields, ISI offers a range of programs from Bachelor's to Junior Research Fellowships. The admission test is scheduled for May 12, 2024. Eligibility varies by program, generally requiring a background in Mathematics and English for undergraduate courses and specific degrees for postgraduate and research positions. Application fees are ₹1500 for male general category applicants and ₹1000 for females. Applications are open to Indian and OCI candidates.
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptx
91121543 roti (1)
1. 1 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
For more details please visit: www.captyashpal.blogspot.com
RATE OF TURN INDICATOR
(R.O.T.I.)
Unlike road vehicles a ship does not turn sharply. With lesser friction in water and under the
influence of momentum a vessel continues on her initial course for some time, beginning to turn
slowly and then rapidly later. Vessel thus traverses a curved track which can be treated as an arc of
a circle.
For small ships such arcs are small and can be executed without much problem. But for large sized
merchant vessels these arcs assume greater radii and need to be treated differently. This becomes
all the more important when vessel is altering courses in restricted waters or in close proximity to
navigational hazards.
For same reasons roundabouts are charted in traffic separation schemes.
Under navigation watch keeping principles, vessel is required to do berth to berth passage
planning. It is also required to lay courses in curved segments as well, where required and to mark
the wheel over positions.
In view of the above, vessels having 50,000 GT and above are mandatorily required to be fitted
with ROTI (Rate Of Turn Indicator) as per Chapter V, SOLAS.
ROTI assists OOW in planning, executing and monitoring vessel’s progress along curved segment
of charted course.
2. 2 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
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The purpose of ROTI is to provide rate of turn to port and to starboard side of ship. The indicator is
usually in the form of a circular dial with zero at top. Port turn is indicated on left of zero and
starboard turn on right of zero. Graduations are provided to indicate ROT up to at least 30
degrees/minute on either side. ROTI can be self-contained, or it may derive information from other
equipment or it may form a part of the other equipment. However, the design is such as to preclude
degradation of other equipment to which ROTI is connected, irrespective of weather ROTI is in
operation or not.
DERIVATION OF FORMULA FOR ROT:
ROT (/t) is expressed in degrees per minute.
Consider following diagram:
PB = Initial course
BN = Final course
AC = Curved segment of charted course;
A is commencement of turn and C is completion of turn.
Length of the curved segment = d
= Amount of alteration in degrees (Angle MBN or Angle AOC)
C
= in radians
R = Radius of the circle of which arc forms the part
t = Time
3. 3 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
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Now, we know that, by definition, radian is the angle subtended at the center of a circle by an arc
equal in length to the radius of the circle. Thus, we have:
C
= d/R = (V x t)/R
Or, /57.3o
= (V x t)/R (Note: is in degrees)
Or, /t = (V x 57.3)/R in degrees /hour
Or, /t = (V x 57.3)/60R in degrees /minute
Using approximation and cancelling 60 and 57.3 with each other, we have:
/t = V/R in degrees /minute
Thus, we have ROT (/t) given by:
EXAMPLE: Let us assume that a vessel’s initial course is 000 (T) and final course is 060 (T). She
is steaming at 15 knots and intends to negotiate a turn about an islet keeping a distance of 1.5
miles. What will be the ROT and how long will she take to complete the turn?
= V (degrees per minute)
t R
So, ROT = V/R = 15 / 1.5 = 10 degrees.
Thus vessel will turn at the rate 10 degrees per minute, while maintaining a distance of 1.5 miles
from the islet.
Now amount of alteration = 60 derees
Thus vessel will take 60/10 = 6 minutes to complete the turn
CONSTANT RADIUS TURN:
In this method radius R is kept constant.
We have seen that rate of turn (ROT) is given by (/t) = V/R
Or, R = V/ (/t)
If radius R is to be kept constant, the expression on the RHS will have to be kept constant. But as
vessel turns, velocity V reduces. Thus ROT (/t) will have to be varied proportionately so as keep
R as constant. Thus in constant radius turn ROT does not remain same and changes as vessel
= V (degrees per minute)
t R
4. 4 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
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negotiates the turn. Constant radius turn is negotiated in the following two ways, depending on
weather the object ‘O’ is visible or imaginary.
Object ‘O’ available as visually or radar conspicuous feature:
1. With O as center and R as radius draw an arc. (The value of R will be decided by
OOW/Master and will depend on vessel’s size, draft, weather conditions, proximity to
other dangers etc,).
2. Draw AB and BC as tangents to the arc, representing initial and final courses
Object ‘O’ not available as visually or radar conspicuous feature:
1. Draw initial and final courses first.
2. Choose suitable value of R depending on size, loading condition of vessel, weather
conditions etc.
3. Calculate AB = BC = R tan /2
4. Draw small arcs, with radius R, from A and C to cut at O.
5. Now O as center and R as radius, draw arc AC. This is the curved segment of the
planned course.
5. 5 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
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MONITORING THE TRACK ALONG CURVED SEGMENT:
Object O is visually conspicuous:
We know that any radius to the point of contact of a tangent is perpendicular to the
tangent. This means that for vessel to remain on the curved track, the object O must
remain abeam or very nearly abeam. If the object is falling abaft the beam, it means that
vessel is going outside the arc (or she is turning slowly) and ROT needs to be increased
by giving greater helm.
Conversely, if object is moving ahead of beam, vessel is going inside the arc (or she is
turning too fast) and ROT needs to reduced by easing the helm.
Object O is radar conspicuous:
In this case VRM along with parallel indexing techniques is utilized for keeping the
vessel on the curved segment of the track. Both RM and TM modes are equally suitable
for the procedure.
6. 6 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
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Object O is imaginary:
In this case vessel’s position has to be closely monitored at more frequent intervals to
ensure that the vessel stays at the curved segment of the track.
With ECDIS onboard:
ECDIS has brought a revolutionary change in the way we navigate ships. The way
computers have made many old human skills irrelevant; ECDIS is also likely to play the
same role. As per IMO performance standards for “route planning and monitoring” on
ECDIS, it should be possible to draw both straight and curved segments of planned courses.
Thus, executing and monitoring ship’s progress along any curved segment is very easy. The
fact that the courses drawn can be seen against the background of chart on the screen itself
makes the procedure a very simple task. ECDIS provides real time fixing. Hence, OOW
knows where the vessel is at any moment rather than where she was few moments ago.
CONSTANT RATE TURN:
In this method ROT (/t) is kept constant.
We know that rate of turn (ROT) is given by (/t) = V/R
If ROT is required to be kept constant, the expression on the RHS will have to be kept constant.
But as vessel turns, velocity V reduces. Thus radius R will have to be varied proportionately so as
to keep ROT as constant. Thus in constant rate turn radius R does not remain same and changes as
vessel negotiates the turn.
Practically ROT is calculated for a mean value of vessel’s speed (mean of speed at the start of
curved segment and speed at the end of curved segment). This value corresponds nearly to vessel’s
position midway on the arc. At other locations on arc value of radius will differ from R. But these
variations are small and within practical and tolerable limits.
WHEEL OVER POINT (WOP):
It is the point on initial course at which wheel is put over to initiate the turning of the vessel. It is
obtained by intersection of initial course by wheel over line.
The distance between the WOP and the ship commencing its turn is denoted by F and depends on:
Size of vessel
Loaded/ballast condition
Trim
Type of vessel etc.
WHEEL OVER LINE:
It is a line drawn parallel to the final course. The point at which it cuts the initial course line is the
wheel over point. The distance at which wheel over line is to be drawn parallel to the final course
is given by following formula:
F Sin + R (1 - Cos)
7. 7 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
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F= distance between WOP and the point when vessel begins to turn.
R= radius of turn
= difference between initial and final course
PROCEDURE:
1. Take F as 0.1, 0.15 or 0.2 miles depending on weather vessel is small, medium or large in
size.
2. Take R as radius of turn, depending on your vessel’s size, draft and external factors.
3. Calculate the distance between WOL and final course by the formula given above.
4. Take any arbitrary point on final course and draw on arc, towards initial course, at the
distance calculated.
5. Draw a tangent to the arc parallel to the final course, cutting the initial course.
6. The point of intersection is the wheel over point.
For illustration purpose only
8. 8 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
For more details please visit: www.captyashpal.blogspot.com
EXAMPLE 1:
A small vessel is coming out of Aberdeen harbour at a course of 056 (T). Her next course is 120
(T). With the Racon Girdle Ness as centre and 0.52 miles as radius, find the WOP.
If the vessel is steaming at 10.4 knots, find the rate of turn and time taken to complete the turn.
SOLUTION:
!Distance between final course and WOL is given by:
F Sin + R (1 - Cos)
Substituting the values, we have:
0.1Sin 64 + 0.52 (1- Cos 64)
= 0.38 miles.
Now, take any arbitrary point on final course and draw an arc at a distance of 0.38 miles. (Refer to
the photo above).
Draw a tangent to the arc parallel to the final course to cut the initial course at T. Now, the parallel
line drawn is the wheel over line and T is the wheel over point.
Now,
Thus, rate of turn = 10.4/0.52 = 20 degrees/minute
Time taken to complete the turn = 64/20 = 3.2 minutes.
EXAMPLE 2:
A small vessel is leaving Aberdeen harbour and is steaming a course of 056 (T) at a speed of 13
knots. Her next course is going to be 190 (T). Draw the courses with curved segment using the
Racon Girdle Ness as centre and 0.52 miles as radius. Also, show the WOP.
How long will she take to arrive at the point of final course?
SOLUTION:
Distance between final course and WOL is given by:
F Sin + R (1 - Cos)
Substituting the values, we have:
0.1Sin 134 + 0.52 (1- Cos 134)
= 0.95 miles.
Now, take any arbitrary point on final course and draw an arc at a distance of 0.95 miles. (Refer to
the photo below).
Draw a tangent to the arc parallel to the final course to cut the initial course at T. Now, the parallel
line drawn is the wheel over line and T is the wheel over point.
Now,
= V (degrees per minute)
t R
9. 9 | P a g e W h a t i s R O T I ( R a t e O f T u r n I n d i c a t o r ) ?
For more details please visit: www.captyashpal.blogspot.com
Thus, rate of turn = 13.0/0.52 = 25 degrees/minute
Time taken to complete the turn = 134/25 = 5.36 minutes.
For illustration purpose only
= V (degrees per minute)
t R