CA1219363A

CA1219363A - Flotation bag assembly

Info

Publication number: CA1219363A
Application number: CA000462265A
Authority: CA
Inventors: Tyler C. Robinson; Wayne J. Sula; Roger C. Larson; William J. Wallace
Original assignee: Hazeltine Corp
Current assignee: BAE Systems Aerospace Inc; Ultra Electronics Ocean Systems Inc
Priority date: 1983-12-15
Filing date: 1984-08-31
Publication date: 1987-03-17
Also published as: NO843450L; NO167192C; EP0145148B1; NZ209269A; AU3182384A; EP0145148A2; JPS60177278A; EP0145148A3; NO167192B; AU565744B2; JPH0645355B2

Abstract

DOCKET E4289.04 FLOTATION BAG ASSEMBLY

ABSTRACT

An apparatus for the stable support of a structure, such as an antenna, in a fluid medium, such as the ocean. A flotation bag supporting an antenna is stabilized by the following features, which can be used individually or in combination. A partially submerged ribbon fence supported by a submerged damper skirt dissipates the kinetic energy of the flotation bag caused by the movement of the ocean and water that encroaches upon the bag. A flexible connection between the bag and the payload enables the bag and the payload to undergo limited motion without affecting each other. Thus, the bag's motion is decoupled and totally independent of the payload. The housing which supports the payload has a flooded chamber, lowering the center of mass of the apparatus. The bottom of the flotation bag is inwardly arched, moving the bouyancy away from the center of the bottom of the bag, enhancing stability and allowing the bag to float lower in the ocean, keeping the damper skirt submerged. The payload includes an r.f. signal source. The apparatus is designed to constrain the motion of the antenna to within very narrow operational limits.

Description

LZ19;3~3 1. FIELD OF INVENTION

6 This invention relates generally to a 7 stable support for structures at or above the surface 8 of a fluid medium and in particular to a 9 communications buoy for use in the ocean.

2. DESCRIPTION OF THE PRIOR ART

11 Many types of flotation devices exist with 12 differing characterisitcs.
1~ Damper plates and toroid shaped flotation 14 devices have been used to create buoys which are wave followers. For example, see Buoy Engineering, H.O.
16 Berteaux, John and Sons, 1976 Pg. 212-213. These 17 surface following buoys are subject to strong heave 18 and pitch due to the motion of the ocean.
19 A more stable buoy can be built by decreasing the cross section of the buoy at the water 21 level~ Such devices experience less heave. The mass 1 of the buoy can also be distributed to create a 2 righting moment. This will decrease the pitch.

3 Further stability can be obtained by

4 surface decoupling. A bouyant cylinder with a counterweight suspended from its bottom is a typical 6 example, Berteaux, supra. Such spar buoys cannot have 7 mucl- reserve bouyancy and usually have a large draft.
8 These factors mitiyate the usefulness of these types 9 of buoys in deep water.

3. SUMMARY OF THE IN_ENTION

11 It is an object of this invention to 12 provide a communications bouy having an antenna which 13 uses the surface of the ocean as a ground plane; such 14 bouy having structure which limits the antenna's motion with respect to the surface of the ocean to 16 within 4 inches heave and 25 pitch.
17 It is another object of this invention to 18 provide a stable bouy that can withstand ocean 19 conditions up to and including state 5.
The buoy according to the invention may be 21 used as part of a search and rescue system for 22 locating downed aircraft and ships in distress. Such 1~1'3~j3 1 buoys would be carried by vehicles and be deployPd 2 when needed. Their distress siynal could be received 3 by satellites and their position located.
4 The bouy according to the invention could carry various other types of payloads or support 6 various antenna structures as well. Other possible 7 uses include oceanographic monitoring buoys and 8 satellite linked sonobuoys.
9 It is an object of this invention to provide an apparatus for the stable support of a 11 structure, such as an antenna, in a fluid medium, such 12 as water.
13 It is a futher object of this invention to 14 limit the motion of an antenna supported above the surface of the ocean) within the operational limits of 16 the transmitting system.
17 It is a further object of this invention 18 to support an electronics payload near the surface of 19 the ocean such that the power loss between the electronics payload and an antenna supported on the 21 surface is within operational limits and, 22 specifically, less than 3db.
23 The invention is an apparatus for the 24 stable support of a structure, such as an antenna, in 1 a fluid medium, such as water. The apparatus 2 comprises a bouyant first member and first means for 3 engaging the structure. The first means is associated 4 with the member. Second means are provided for channeling the fluid which encroaches upon the bouyant 6 mem~er due to any motion of the member with respect to 7 the surface of the fluid medium, the encroaching fluid 8 being channeled back into the fluid medium such that 9 the kinetic energy of the bouyant first member is dissipated as the fluid is channeled back into the 11 fluid medium.
12 Alternatively, the apparatus according to 13 the invention may comprise a bouyant first member for 14 supporting the structure, a payload and decoupling means for supporting the payload below the bouyant 16 member such that any motion of the payload is 17 decoupled from the member and any motion of the member 18 is decoupled from the payload.
19 Alternatively, the apparatus according to the invention may comprise a bouyant member with an 21 inwardly arched bottom portion, and means! associated 22 with the bouyant member, for engaging the structure.
23 Alternatively, an apparatus according to 24 the invention may comprise an antenna, a bouyant member, first means for generating an r.f. signal, '3;3~j~

1 second means interconnecting the first means and the 2 antenna, and decoupling means for supporting the first 3 means below the bouyant member such that any motion of 4 the member is decoupled from the first means and the motion of the first means is decoupled from the 6 member.
7 Alternatively~ the invention may comprise 8 a communications bouys which is stable in a fluid 9 medium and includes structures for minimizing the heave and pitch of the bouy. Specifically, a 11 flotation bag with a concave bottom formed by pulling 12 in the center of the bottom of the bag with straps 13 secured to the inside walls of the bag supports an 14 antenna. A semi-rigid damper skirt extending around the base of the bag is submerged when the apparatus is 16 floating in the fluid medium. The bag is provided 17 with a ribbon fence comprising containers which have 18 an opening above the fluid level, and an opening below 19 the fluid level, when the apparatus is floating in the medium, allowing the fluid to flow in and out of the 21 containers. The payload is supported in a cylindrical 22 chamber connected to the flotation bag by a flexible 23 cable, enabling the payload to swing.

tj~3 1 BRIEF DES~RIPTION OF THE DRAWINGS

2 Fiyure 1 is a side view of a 3 communications bouy according to the invention 4 deployed in water.
Figure 2 is a side view of the bouy of 6 Figure 1 with parts broken away to illustrate internal 7 structure.
8 Figure 3 is a perspective view of a 9 communications bouy according to the invention in an undeployed state.
11 Figure 4 is a top view of a flotation bag 12 according to the invention.
13 Figures 5a -59 are graphs illustrating the 14 operational transmission requirements and the estimated performance of an antenna system according 16 to the invention under varying conditions of heave and 17 pitch.
.

19 Referring to figures 1 and 2, flotation bag 1 is an inflated balloon-like structure having a 21 specific gravity less than the specific gravity of 22 fluid medium W. Bag 1 encloses antenna 2 and supports 23 a payload 3 below the surface of medium W.

.. .

3~
1 Although this embodiment comprises 2 flotation bag 1 which encloses antenna 2, the 3 invention includes flotation devices of any type which 4 support structures.
Figures 5a-5y compare the estimated 6 performance lû2 of an antenna such as antenna 3 under 7 varying conditions of heave and pitch with the 8 operational performance requirement 101 for successful 9 transmission. Antenna 3 uses the surface of the fluid W as a ground plane. Heave and pitch disturb the 11 relationship between the radiating antenna 3 and the 12 ground plane, changing the radiation pattern of 13 antenna 3. As shown by graphs 5a, 5b, and 5f, the 14 estimated performance 102 of antenna 3 crosses and falls below the operational performance requirements 16 for successful transrnission between points lû3 and 17 lG4. In summary, successful transmission is not 18 achieved when antenna 3 undergoes more than 4 inches 19 heave or 25 pitch. The apparatus according to the invention limits the motion of the antenna relative to 21 the ground plane to within 4 inches heave and 25 22 pitch, under ocean conditions up to sea state 5.
23 A damper skirt 4 extends around the base 24 of the flotation bag 1 and is made of a semi-rigid material supported in a horizontal position by ribbon 26 fence 5.

1 When the apparatus is afloat, damper skirt 2 4 is ~elow the surface of the medium W. The weight of 3 the payload 3, the shape of the bottom of the 4 flotation Dag 1 and the bouyancy of bag 1, which will be described in detail below, are configured so that 6 damper skirt 4 is below the water line when the 7 apparatus is stable.
8 Damper skirt 4 increases the surface area 9 in contact with the ocean, offering a surface which resists motion V within medium W. In order to rise or 11 tip in response to a wave, damper skirt 4 must travel 12 upwardly through the fluid. The resistance to upward 13 movement of skirt 4 is caused by the fluid above the 14 skirt 4. The energy that would otherwise cause heave and pitch of the flotation bag 1 is dissipated by this 16 resistance and any resulting movement of skirt 4 17 within the medium W.
18 As shown particularly in figure 4, ribbon 19 fence 5 which supports the damper skirt 4 is a series of contiguous compartments, 5a-5g. Damper skirt 4 21 acts as the base of the compartments 5a-5g of ribbon 22 fence 5 and the side ls of the flotation bag 1 forms 23 the back wall of the compartments. The walls of the 24 compartments in the embodiment illustrated comprise a strip of semi-rigid material connected to the side of 3~i3 1 the flotation bag 1 at spaced apart points P. The 2 flotation bag 1, damper skirt 4 and the strip form the 3 contiguous compartments, the combination of which is 4 referred to herein as ribbon fence 5.
Each compartment 5a-5g has an opening 6 in 6 the lower portion thereof, where the strip joins to 7 damper skirt 4. The compartments have an opened top 8 7. When sta~le in the ocean, the bottom hole 6, which 9 has a cross section less than the opening at the top 7, is beneath the level of the medium W. The water 11 line on the flotation bag when the apparatus is at 12 rest in the ocean is approximately at the midpoint 8 13 of the height oF the ribbon fence 5.
14 Compartments 5a-5h act as containers for the fluid medium. Fluid encroaching upon bag 1 can 16 enter the compartments through hole 6 or the opened 17 top 7 and can drain from the compartments through the 18 hole 6. When bag 1 rises due to the motion of the 19 ocean, sea water will drain out of the holes 6, dissipating the kinetic energy of bag 1 created by the 21 rising motion of the ocean. Oscillating of the 22 ~lotation bag 1 within the medium W are thereby 23 damped. The compartments increase the resistance to 24 motion of damper skirt 4 by partially enclosing the fluid and by requiring the damper skirt to lift the 1 partially enclosed fluid in the compartments as the 2 flotation bag 1 rises in response to a wave. This 3 acts to further decrease the heave and pitch of the 4 flotation bag.
S The damper skirt 4 and ribbon fence 5 are 6 described associated with each other, constructed from 7 semi-rigid materials for the purpose of stabilizing 8 flotation bag 1. However, the damper skirt 4 may be a 9 submerged plate and the means for channeling fluid that encroaches on the device. Such structures may be 11 used separately or in combination to decrease both the 12 heave and pitch of the device.
13 Payload 3 comprises electronics 31 14 enclosed in a cylindrical housing 32. Housing 32 is connected to the bottom of the flotation bag 1 by 16 nylon cord 8. One end of nylon cord 8 connects to a 17 point 8a within the housing, approximately one-quarter 18 from the top of the housing and the other end connects 19 to the center of the bottom of the bag 8b, at bulkhead 9, which is a rigid portion. Electrical wires 311 21 also pass from the electronics 31 into the bulkhead 22 9. Beneath the bulkhead 9 is microphonics bumper 91.
23 Nylon cord 8 and the location of the 24 connection between the housing 32 and the flotation bag 1, at 8a and 8b, decouple the motion of flotation 3;3t:~

1 bag 1 from housing 32 such that, over a certain range, 2 the motion of bag 1 does not affect the motion of 3 cylindrical housing 32 and the motion of cylindrical 4 housing 32 does not affect the housing motion of bag 1. The range of motion depends on the demensions of 6 the decoupling apparatus including the diameter of 7 housing 32 and the distance between the top of housing 8 32 and microphonic bumper 91.
9 Housing 32 is free to swing like a pendulum until the top of the housing 32a collides 11 with the microphonic bumper 91. Similarly, the 12 flotation bag 1 can freely pitch until the bumper 91 13 collides with the top of the housing 32a.
14 This allows for 10 - 15 of motion of the payload 3, measured from the vertical, before 16 contact between housing 32a and microphonic bumper 17 91. Bumper 91 absorbs some of the energy of any 18 impact between bag 1 and payload 3, decreasing the 19 effect such impact would have on the heave and pitch of the flotation bag. Bumper 91 also protects the 21 electrical wiring that feed to the antenna, preventing 22 interruption or interference with the transmission of 23 a message due to impacts between the housing 32a and 24 the bulkhead 9 through which wires 311 pass.
In the embodiment illustrated, electronics 26 31 is close to antenna 2 in order to minimize the ti3 ~ po~er loss due to transmission of a signal from 2 electronics 31 to antenna 2 via cable 311.
3 Preferably, the power loss is less than 3db.
4 The upper portion 33, of housing 32, referred to herein as a collar, stores the entire 6 flotation apparatus before it is deployed, as shown in 7 Figure 3. After deployment, the upper portion 33 8 floods with water, through holes 121 in its sides, as 9 shown in Figures 1 and 2. The flooding reduces the bouyancy of the payload 3 which results in payload 3 11 pulling the flotation bag 1 into the water, ensuring 12 that the damper skirt 4 and bottom hole 6 of ribbon 13 fence 5 are submerged. This increases the stability 14 of flotation bag 1.
The flooding of upper portion 33 results 16 in the center of mass of housing 32 being lower in the 17 medium W, increasing the period of oscillation of 18 housing 32. This staoilizes the entire structure and 19 decreases the heave and pitch of flotation bag 1.
The center of the bottom of the flotation 21 bag 1 is pulled upward by straps 13 secured at 131, 22 along the inside wall of flotation bag 1. This 23 reduces the bouyancy of bag 1, aiding in maintaining 24 the necessary waterline above damper skirt 4 and at the midpoint of ribbon fence 5. The base of bag 16 is 1 inwardly arched at its center 15 so that the greatest 2 bouyant forces are located at the outer portions of 3 the bag 16. This decreases the pitch of the flotation 4 bag 1 by creating a lonyer torque arm which must be overcome for the flotation bag to rotate. This 6 riyhtiny moment further aids in stabilizing the 7 flotation bag. The adhesion caused by inwardly arched 8 center 15 between the surface of the bottom 16 of the 9 bag and the fluid medium W also decreasès the heave of the flotation bag.
11 Although this particular embodiment 12 describes a flotation bag with a concave bottom, the 13 invention is meant to cover flotation devices of any 14 material with a bottom of inwardly arched shape.
The apparatus and payload are ejected in 16 the cylindrical housing 3, as shown in Figure 3.
17 Antenna 4, flotation bag 1, ribbon fence 5 and damper 18 skirt 4 are all stored in upper chamber 33 of the 19 housing 32. Houslng 32, which is bouyant, floats to the surface of the ocean after being ejected. The 21 flotation bag and antenna are then deployed and the 22 preprogrammed messages are transmitted.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OF PRIVILEGE IS CLAIMED ARE DEFINED AS
FOLLOWS:

What is claimed is:

Claim 1. An apparatus for the stable support of a structure, such as an antenna, in a fluid medium, such as water, said apparatus comprising:
a. a bouyant first member;
b. first means for engaging the structure, said means associated with the member; and c. second means for channeling the portion of the fluid which encroaches upon the bouyant member due to any motion of the member with respect to the surface of the fluid medium, said encroaching fluid being channeled back into the fluid medium such that the kinetic energy of the bouyant first member is dissipated as the fluid is channeled back into the fluid medium.
Claim 2. An apparatus as in claim 1 wherein the second means comprises at least one container with an upper opening and a lower opening, said container connected to the bouyant first member such that the upper opening is above the level of the fluid medium and the lower opening is below the level of a fluid medium when the apparatus is floating in the medium, whereby encroaching fluid which enters the container flows out of the lower opening.
Claim 3. An apparatus as in claim 2, wherein said container is a ribbon fence.
Claim 4. An apparatus as in claim 3, wherein said ribbon fence comprises a plurality of adjacent compartments having an open top and an opening at the bottom, said bottom opening having a cross sectional area less than the cross sectional area of the top opening.
Claim 5. An apparatus as in claim 4 9 wherein each said compartment comprises a substantially vertical wall and a base, with the lower opening formed between the wall and the base.
Claim 6. An apparatus as in claim 5, wherein the compartment is further defined by the vertical wall and a surface of the first bouyant member.
Claim 7. An apparatus as in claim 2, wherein said container is associated with a substantially horizontal member extending around the bouyant member, beneath the level of the fluid medium when the apparatus is afloat.
Claim 8. An apparatus as in claim 7, wherein said horizontal member is damper skirt.
Claim 9. An apparatus as in claim 8, wherein the damper skirt is semi-rigid disk which impedes the motion of the apparatus in the medium, thereby decreasing the heave and pitch of the bouyant member.
Claim 10. An apparatus as in claim 5, wherein the base of the containers is the damper skirt supported in a substantially horizontal position.
Claim 11. An apparatus as claim 1 further comprising a payload and decoupling means for supporting the payload below the bouyant member such that motion of the payload within a given range is decoupled from the member and motion of the member within a given range is decoupled from the payload.
Claim 12. An apparatus as in claim 11 wherein the payload includes a housing and said decoupling means is a flexible member interconnecting the housing and the bouyant member.
Claim 13. An apparatus as in claim 12 wherein said housing has a collar extending from the housing and surrounding the flexible member.
Claim 14. An apparatus as in claim 13 wherein:
a. the bouyant first member has a rigid portion, b. said flexible member is connected to said rigid portion, and c. said rigid portion has a bumper for engaging the collar when the pivotal movement of the housing with respect to the rigid portion is greater than a predetermined angle within the given range.
Claim 15. An apparatus as in claim 14 wherein said bumper is a microphonics bumper and the predetermined angle is approximately 10°.
Claim 16. An apparatus as in claim 14 wherein said collar forms a chamber which is flooded after the apparatus is deployed in the fluid medium.
Claim 17. An apparatus as in claim 11 wherein said housing includes a chamber within which said bouyant member is stored when the apparatus is in an undeployed state.
Claim 18. An apparatus as in claim 11 further comprising a damper skirt associated with said bouyant member.
Claim 19. An apparatus as in claim 1 wherein said bouyant member has an inwardly arched bottom portion.
Claim 20. An apparatus as in claim 19 wherein the bottom of the bouyant member is concave.
Claim 21. An apparatus as in claim 20 wherein the bouyant member is a flotation bag having straps connected to the inside walls of the bag and the center of the bottom of the bag, pulling the center of the bottom of the bag inward, forming the concave shape.
Claim 22. An apparatus as in claim 7 wherein said bouyant member has an inwardly arched bottom portion.
Claim 23. An apparatus as in claim 11 wherein said bouyant member has an inwardly arched bottom portion.
Claim 24. An apparatus as in claim 18 wherein said bouyant member has an inwardly arched bottom portion.
Claim 25. An apparatus as in claim 11 further comprising an antenna supported by said bouyant member, first means for generating an r.f.
signal included in said payload and means interconnecting said antenna and said first means.
Claim 26. An apparatus as in claim 18 further comprising an antenna supported by said bouyant member, first means for generating an r.f.
signal included in said payload and means interconnecting said antenna and said first means.
Claim 27. An apparatus as in claim 23 further comprising an antenna supported by said bouyant member, first means for generating an r.f.
signal included in said payload and means interconnecting said antenna and said first means.
Claim 28. An apparatus as in claim 24 further comprising an antenna supported by said bouyant member, first means for generating an r.f.
signal included in said payload and means interconnecting said antenna and said first means.
Claim 29. An apparatus for the stable support of a structure, such as an antenna, in a fluid medium, such as water, said apparatus comprising;
a. a bouyant first member for supporting the structure;
b. a payload; and c. decoupling means for supporting the payload below the bouyant member such that motion of the payload within a given range is decoupled from the member and motion of the member within the given range is decoupled from the payload.
Claim 30. An apparatus as in claim 29, wherein said payload includes a housing and said decoupling means comprises a flexible member interconnecting the housing and the bouyant member.
Claim 31. An apparatus as in claim 30, wherein the housing has a collar extending from the housing and surrounding the flexible member.
Claim 32. An apparatus as in claim 31 wherein a. the bouyant first member has a rigid portion at the center of the bottom of the member;
b. said flexible member connects to said rigid portion; and c. said rigid portion has a bumper for engaging the collar when the pivotal movement of the housing with respect to the rigid portion is greater than a predetermined angle within the given range.
Claim 33. An apparatus as in claim 32 wherein the predetermined angle is approximately 10°.
Claim 34. An apparatus as in claim 31 wherein said collar forms a chamber whereby the chamber is flooded after the apparatus is deployed in the fluid medium.
Claim 35. An apparatus as in claim 31 wherein said housing includes a chamber within which said member is stored before it is deployed.
Claim 36. An apparatus as in claim 29 further comprising a damper skirt associated with said bouyant member.
Claim 37. An apparatus as in claim 29 wherein the bouyant member has an inwardly arched bottom portion.
Claim 38. An apparatus as in claim 37 wherein the bottom of the bouyant member is concave.
Claim 39. An apparatus as in claim 38 wherein the bouyant member is a flotation bag having straps connected to the inside walls of the bag and the center of the bottom of the bag, pulling the center of the bottom of the bag inward, forming the concave shape.
Claim 40. An apparatus as in claim 36 wherein the bouyant member has an inwardly arched bottom.
Claim 41. An apparatus as in claim 29 further comprising an antenna supported by said bouyant member, first means for generating an r.f.
signal included in said payload and means interconnecting said antenna and said first means.
Claim 42. An apparatus as in claim 41 further comprising a damper skirt associated with said bouyant member.
Claim 43. An apparatus as in claim 42 wherein the bouyant member has an inwardly arched bottom portion.
Claim 44. An apparatus for the stable support of a structure, such as an antenna, in a fluid medium, such as water, said apparatus comprising;
a. a bouyant member;
b. means for engaging the structure, said means associated with the bouyant member;
and c. said bouyant member having an inwardly arched bottom portion.
Claim 45. An apparatus as in claim 44, wherein the bottom of the bouyant member is concave.
Claim 46. An apparatus as in claim 45 wherein the bouyant member is a flotation bag having straps connected to the inside walls of the bag and the center of the bottom of the bag, pulling the bottom of the bag inward forming the concave shape.
Claim 47. An apparatus as in claim 46 further comprising a damper skirt associated with said member.
Claim 48. An apparatus for the stable support of a structure, such as an antenna, in a fluid medium, such as water, said apparatus comprising, a. an antenna;
b. a bouyant member;
c. first means for generating an r.f.signal;
d. second means interconnecting the first means and the antenna; and e. decoupling means for supporting the first means below the bouyant member such that any motion of the member is decoupled from the first means and the motion of the first means is decoupled from the member.
Claim 49. An apparatus as in Claim 48 wherein the bouyant member has a ribbon fence associated with said bouyant member.
Claim 50. An apparatus as in claim 49 wherein the bouyant member has a damper skirt associated with said member.
Claim 51. An apparatus as in claim 49 wherein the r.f. signal provided to the antenna by the second means has an amplitude which is less than 3db below the amplitude of the r.f. signal provided by the first means.
Claim 52. A communications bouy which is stable in a fluid medium, and which includes structure for minimizing the heave and pitch of the bouy, said bouy comprising:
a. an antenna, b. a flotation bag with a concave bottom formed by pulling in the center of the bottom of the bag with straps secured to the inside walls of the bag, said bag supporting said antenna, c. a semi-rigid damper skirt extending around the base of the bag, which is submerged when the apparatus is floating in the fluid medium;
d. a ribbon fence comprising containers with an opening above the fluid level, and an opening below the fluid level, when the apparatus is floating in the medium, allowing the fluid to flow in and out of the containers;
e. a damper skirt associated with said bag for impeding the heaving and pitching motion of the flotation bag, said containers supporting the damper skirt in a substantially horizontal position, f. a payload including first means for generating an r.f. signal, g. a longitudinal, cylindrical housing for supporting the payload, said housing having a floodable chamber, said housing connected to a rigid portion of the flotation bag by a flexible cable surrounded by said chamber, enabling the housing to swing.
Claim 53. The bouy of claim 52 wherein said bag supports said antenna above the surface of the fluid medium such that the surface of the fluid medium functions as a ground plane with respect to the antenna when the antenna is radiating due to r.f.
excitations from the first means.