Patent Publication Number: US-11656217-B2

Title: Sensing device, sensing device system, and methods for measuring a characteristic of a concrete mixture and for predicting a performance characteristic of a concrete mixture

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. application Ser. No. 16/502,947 filed Jul. 3, 2019, now U.S. Pat. No. 11,237,150 issued Feb. 1, 2022, which is a continuation of U.S. application Ser. No. 15/420,635 filed Jan. 31, 2017, now U.S. Pat. No. 10,386,354, issued Aug. 20, 2019, which claimed the priority to U.S. Provisional Application No. 62/289,723 filed Feb. 1, 2016, U.S. Provisional Application No. 62/343,635 filed May 31, 2016, and U.S. Provisional Application No. 62/356,378 filed Jun. 29, 2016. The priority of each of these applications is claimed and the contents of each of these applications are incorporated by reference. 
    
    
     TECHNICAL FIELD 
     This specification relates generally to the construction field, and more particularly to a sensing device, sensing device system, and methods for measuring a characteristic of a concrete mixture and for predicting a performance characteristic of a concrete mixture. 
     BACKGROUND 
     Concrete is generally used within the industry to refer to a mixture of cement, sand, stone, and water f upon aging turns into a hardened mass. The term concrete, as used in the specification and claims herein, means not only concrete as it is generally defined in the industry (cement, sand and stone), but it also means mortar (cement, sand and water) and cement (cement and water which hardens into a solid mass upon aging). 
     In the construction field, after a batch of concrete has been produced for use at a particular site, it is useful to be able to obtain data concerning certain performance characteristics such as the in-place strength of the batch. Accurate prediction of concrete performance can increase the quality of the end product and can provide other benefits such as allowing the use of accelerated construction schedules. 
     Several methods for testing and monitoring in-place strength of a concrete mass have been incorporated into the American Standard. Testing Methods, including ASTM C805 (The Rebound Number Method—the so-called Swiss Hammer Method), ASTM C597 (The Pulse Velocity (Sonic) Method), ASTM C74 (The Maturity Method), and ASTM C900 (The Pullout Strength Method). 
     In accordance with standards set forth in ASTM C31 (Standard Practice for Making and Curing Concrete Test Specimens in the Field), the compressive strength of concrete is measured to ensure that concrete delivered to a project meets the requirements of the job specification and for quality control. In order to test the compressive strength of concrete, cylindrical test specimens are cast in test cylinders and stored in the field until the concrete hardens. 
     In accordance with the standards, typically 4×8-inch or 6×12-inch test cylinders are used, and the concrete filed specimens are first stored within the project site location for their initial hardening, and then moved to a lab or a carefully selected location for a predetermined period of time and cured under moist conditions and a constant temperature of 20 dC. When making cylinders for acceptance of concrete, the field technician must test properties of the fresh concrete including temperature, slump, density (unit weight) and air content. 
     There is an ongoing need for improved systems and methods for measuring and predicting the strength and performance of concrete. 
     SUMMARY 
     In accordance with an embodiment, a sensing device is attached to the side of a concrete test cylinder. The sensing device has a concave side adapted to conform to a curvature of the outer side of the concrete test cylinder. The sensing device includes a temperature sensor and a humidity sensor. After concrete is poured into the test cylinder, the sensing device obtains temperature measurements and/or humidity measurements. 
     In one embodiment, the sensing device includes a housing and a cavity defined inside the housing. The temperature sensor and the humidity sensor are disposed within the cavity. The sensing device may also include a transmitter or other communication device disposed within the cavity. 
     In one embodiment, the sensing device includes a capillary needle disposed on and projecting outwardly from the concave side of the device. The capillary needle connects to a humidity sensor. 
     In accordance with another embodiment, a measurement system includes a concrete test cylinder. The side of the cylinder has an outer surface having a convex shape, and the side has particular thickness. A hole is disposed in the side of the cylinder. The measurement system also includes a sensing device. The sensing device has a concave side adapted to conform to the convex shape of the outer surface of the side of the concrete test cylinder. The sensing device includes a temperature sensor and a capillary needle which is disposed on the concave side of the sensing device and projects outwardly from the concave side. The capillary needle connects to a humidity sensor and has a length substantially equal to the thickness of the side of the cylinder. 
     In accordance with another embodiment, a method includes attaching a sensing device to a side of a concrete test cylinder, receiving temperature and humidity measurements from the sensing device, and computing maturity from temperature measurements which is used to generate predictions of strength of the concrete, with due regard to the humidity measurements. 
     In accordance with another embodiment, a communication system includes a network and a sensing device attached to a cylinder that contains a concrete mixture. The sensing device is adapted to obtain temperature measurements and humidity measurements. The sensing device is connected to the network. The communication system also includes a processor connected to the network, the processor being adapted to receive the temperature measurements and humidity measurements, and to generate a prediction of a performance characteristic of the concrete mixture based on the temperature and humidity measurements. 
     These and other advantages of the present disclosure will be apparent to those of ordinary skill in the art by reference to the following Detailed Description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    shows an exemplary test cylinder containing a test specimen of concrete; 
         FIG.  2 A  shows a sensor patch in accordance with an embodiment; 
         FIG.  2 B  shows a sensor patch in accordance with another embodiment; 
         FIG.  2 C  shows components of a sensor patch in accordance with an embodiment; 
         FIG.  3 A  shows a sensor patch attached to a concrete test cylinder in accordance with an embodiment; 
         FIG.  3 B  shows a side-view cross-section of a sensor patch and of a concrete test cylinder in accordance with an embodiment; 
         FIG.  3 C  shows a top-view cross-section of a sensor patch and of a concrete test cylinder in accordance with an embodiment; 
         FIG.  4 A  shows a perspective view of a sensor patch in accordance with an embodiment; 
         FIG.  4 B  shows a cross-section of sensor patch in accordance with an embodiment; 
         FIG.  5 A  shows sensor patch attached to a side of a concrete test cylinder in accordance with an embodiment; 
         FIG.  5 B  shows a cross-section of a sensor patch and of a side of a concrete test cylinder in accordance with an embodiment; 
         FIG.  6 A  shows a communication system in accordance with an embodiment; 
         FIG.  6 B  shows a communication system in accordance with another embodiment; 
         FIG.  7    is a flowchart of a method in accordance with an embodiment; 
         FIG.  8    includes a graph showing observed temperature over time measured after a concrete mixture has been poured into a test cylinder; 
         FIG.  9    shows an exemplary computer which may be used to implement certain embodiments; 
         FIG.  10 A  shows a sensing system in accordance with an embodiment; 
         FIG.  10 B  shows a cross-section of container and of a pocket in accordance with an embodiment; 
         FIG.  10 C  shows a top view of a sensing system in accordance with an embodiment; 
         FIG.  11 A  shows a sensing system and a concrete test cylinder in accordance with an embodiment; 
         FIG.  11 B  shows a concrete test cylinder placed in sensing system in accordance with an embodiment; 
         FIG.  12 A  shows a first side of a sensor patch in accordance with an embodiment; 
         FIG.  12 B  shows a second (opposite) side of the sensor patch of  FIG.  12 A ; 
         FIG.  12 C  shows a side-view cross-section of the sensor patch of  FIG.  12 A ; 
         FIG.  12 D  shows a top-view cross-section of the sensor pouch of  FIG.  12 A ; 
         FIGS.  13 A- 13 B  show a temperature sensor within a sensor pouch in accordance with an embodiment; 
         FIG.  14 A  shows a sensor pouch attached to an outer surface of a concrete test cylinder in accordance with an embodiment; 
         FIG.  14 B  shows a cross-section of a sensor pouch and of a concrete test cylinder in accordance with an embodiment; 
         FIG.  15    shows components of a sensor patch  1500  in accordance with another embodiment; 
         FIG.  16 A  shows a top view of a sensor pouch in accordance with an embodiment; 
         FIG.  16 B  shows a side view of the sensor patch of  FIG.  16 A ; 
         FIG.  16 C  shows a front view of the sensor patch of  FIG.  16 A ; 
         FIG.  16 D  shows a side view cross-section of the sensor patch of  FIG.  16 A ; 
         FIG.  17 A  shows a bottom view of a cover in accordance with an embodiment; 
         FIG.  17 B  shows a first side view of the cover of  FIG.  17 A ; 
         FIG.  17 C  shows a second side view of the cover of  FIG.  17 A ; 
         FIG.  18    shows a sensor patch attached to a side of a test cylinder in accordance with an embodiment; 
         FIG.  19    shows a cylinder enclosure system in accordance with an embodiment; 
         FIGS.  20 - 22    illustrate a method of placing a test cylinder in a cylinder enclosure system in accordance with an embodiment; 
         FIG.  23    shows a cylinder enclosure system in accordance with an embodiment; and 
         FIG.  24    shows a cylinder enclosure system in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     In accordance with standards set forth in ASTM C31 (Standard Practice for Making and Curing Concrete Test Specimens in the Field), the compressive strength of concrete is measured to ensure that concrete delivered to a project meets the requirements of the job specification and for quality control. In order to test the compressive strength of concrete, cylindrical test specimens are cast in test cylinders and stored in the field until the concrete hardens.  FIG.  1    shows an exemplary test cylinder  110  containing a test specimen of concrete  162 . 
       FIG.  2 A  shows a sensor patch in accordance with an embodiment. Sensor patch  200  includes a sensing device. Sensor patch  200  may be any size and have any shape. In one embodiment, sensor patch  200  has a square shape and is approximately 30-50 mm on each side. In one embodiment, sensor patch  200  is approximately 3-15 mm thick. One side  215  of sensor patch  200  has a concave shape. In the illustrative embodiment of  FIG.  2 A , side  215  of sensor patch  200  has a concave shape; and the opposite side is convex. In another illustrative embodiment shown in  FIG.  2 B , side  215  of sensor patch  200  is concave; however, the opposite side is flat. 
     Sensor patch  200  is adapted to fit on the outer surface of a standard concrete test cylinder. Referring to the illustrative embodiment of  FIG.  2 A , for example, concave side  215  is shaped to conform to the curvature of the outer surface of a side of a concrete test cylinder. For example, sensor patch  200  may be adapted to fit on the outer surface of a side of a standard 4×8-inch or 6×12-inch concrete test cylinder. A sensor patch may be adapted to fit on other containers having other sizes, such as cubic 150 mm and 200 mm concrete molds used in Europe, in which case both sides of the sensor patch would be flat. 
       FIG.  2 C  shows components of sensor patch  200  in accordance with an embodiment. Sensor patch  200  includes a temperature sensor  291  and a humidity sensor  293 . Sensor patch  200  also includes GPS-based location detector. Sensor patch  200  also includes a communication device  297 , which may be a transmitter or transceiver. Communication device  297  is capable of transmitting data (e.g., measurement data) to a remote device. For example, communication device  297  may transmit data wirelessly. Sensor patch  200  may include other types of sensors not shown in  FIG.  2 C . 
     It has been observed that heat flows readily through the side of a standard concrete test cylinder. As a result, temperature measurements obtained at or near the outer surface of a test cylinder can be used to determine, or to estimate, temperature and other characteristics of the concrete contained the test cylinder. Tests confirm that sensor patch temperature measurements are very close to concrete temperature inside the mold. Thus sensor patch devices can record sufficiently accurate temperatures without in any way intruding into the concrete inside the cylinder, and thus in any way making the test specimen unfit for a standard compression test. Thus, uniquely one can both record the test cylinder&#39;s temperature and perform an acceptable compression test on it. 
     Thus, in accordance with an embodiment, a sensor patch is attached to the side of a concrete test cylinder. A sensor patch may be attached, for example, by an adhesive, by a mechanical fastener, by a magnetic fastener, or by another mechanism.  FIG.  3 A  shows sensor patch  200  attached to a test cylinder  300  in accordance with an embodiment. In particular, sensor patch  200  is attached to a side  305  of test cylinder  300 . Because test cylinder  300  has a cylindrical shape, an outer surface of side  305  has a convex shape. When attached to side  305  of cylinder  300 , concave edge  215  of sensor patch  200  allows the concave surface of sensor patch  200  to be flush with the convex outer surface of side  305  of cylinder  300 . 
     Advantageously, the concave shape of sensor patch  200  allows a large portion of the surface of sensor patch  200  to be in contact with, or proximate to, the surface of side  305  of cylinder  300 . This contact, or proximity, between a large portion of the surface of sensor patch  200  and the surface of the side of cylinder  300  enables sensor patch to obtain more accurate temperature measurements. 
       FIG.  3 B  shows a side-view cross-section of test cylinder  300  and of sensor patch  200  in accordance with an embodiment. Concave side  215  of sensor patch  200  is in contact with side  305  of test cylinder  300 . In the illustrative embodiment, test cylinder  300  holds a concrete mixture  309 . 
       FIG.  3 C  shows a top-view cross-section of test cylinder  300  and of sensor patch  200  in accordance with an embodiment. Concave side  215  of sensor patch  200  conforms to the convex shape of side  305  of cylinder  300 . 
     In accordance with an embodiment, concrete is poured into cylinder  300 . After the concrete is poured into cylinder  300 , sensor patch  200  obtains temperature and humidity measurements. Sensor patch  200  may transmit the measurement data to a second device, such as a computer located at a remote location. 
       FIGS.  4 A- 4 B  show a sensor patch in accordance with another embodiment.  FIG.  4 A  shows a perspective view of a sensor patch  400  in accordance with an embodiment.  FIG.  4 B  shows a cross-section of sensor patch  400  in accordance with an embodiment. Sensor patch  400  includes a concave side  415 , and a capillary needle  430  which is disposed on concave side  415  and projects outwardly from concave side  415 . While the sensor patch  400  is reusable, the capillary needle is disposable since after each test it can be removed and another needle reinstated into the sensor. To protect the sensor from water intrusion, the sensor end of the capillary needle is sealed in Gortex which allows passage of water vapor, but not water liquid. 
     Capillary needle  430  connects to a humidity sensor. For example, capillary needle  430  may be connected to humidity sensor  293 . Capillary needle  430  has a length approximately equal to the thickness of the side of a concrete test cylinder. In one embodiment, the side of a standard concrete test cylinder is approximately 2-3 mm thick. Therefore, capillary needle  430  has a length of approximately 2-3 mm. 
     In accordance with an embodiment, the side of a test cylinder has a small hole, which may be, for example 1-3 mm in diameter. In accordance with an embodiment, sensor patch  400  is attached to the side of the test cylinder in a manner that causes capillary needle  430  to penetrate the hole in the side of the cylinder. 
       FIG.  5 A  shows sensor patch  400  attached to a side  505  of a test cylinder  500  in accordance with an embodiment.  FIG.  5 B  shows a cross-section of sensor patch  400  and of side  505  of test cylinder  500  in accordance with an embodiment. In the illustrative embodiment, test cylinder  500  holds a concrete mixture  509 . 
     A hole  550  is present in side  505  of test cylinder  505 . Sensor patch  400  is attached such that sensor patch  400  is proximate to side  505  of test cylinder  400 , and capillary needle  430  penetrates into hole  550 . Because capillary needle  430  has a length that corresponds to the thickness of side  505  of cylinder  500 , capillary needle  430  penetrates into hole  550  and extends through the length of hole  550 , but does not project out of hole  550  on the opposite side (i.e., capillary needle  430  does not extend into the inside of cylinder  500 ). Consequently, capillary needle  430  does not penetrate into concrete mixture  509  within test cylinder  500 . 
     After sensor patch  400  is attached to cylinder  500 , temperature sensor  291  (shown in  FIG.  2 C ) of sensor patch  400  obtains temperature measurements. Capillary needle  430  obtains humidity measurements. Sensor patch  400  may transmit temperature and humidity measurement data to a second device. 
     In accordance with an embodiment, temperature and humidity measurements obtained by a sensor patch are used to determine a prediction of a characteristic of the concrete mixture contained in a test cylinder.  FIG.  6 A  shows a communication system in accordance with an embodiment. Communication system  600  includes test cylinder  500 , sensor patch  400 , and a computer  618 . Computer  618  includes a prediction module  622 , which is adapted to generate a prediction of a selected characteristic of a concrete mixture based on temperature and humidity measurements. Methods for determining strength from maturity are known, and maturity itself can be computed for a measured curing temperature versus age profile, and other characteristics of a concrete mixture based on temperature and humidity measurements are also known. 
       FIG.  6 B  shows a communication system in accordance with another embodiment. Communication system  660  includes a network  605 , which may include the Internet, for example, a master database module  635 , a prediction manager  640 , and a cloud storage  670 . 
     Communication system  660  also includes a local gateway  683 , which is connected to network  605 . Local gateway  683  includes a wireless modem  685 . Local gateway  683  is linked to a plurality of sensor patch systems  400 -A,  400 -B, which are attached to respective test cylinders  500 -A,  500 -B. Local gateway  683  is also linked to a local storage  688 . Local gateway  683  may from time to time store data, such as measurement data received from sensor patch systems  400 , in local storage  688 . Local gateway  683  and local storage  688  may be located at or near a construction site, for example. 
     Sensor patch systems  400 -A,  400 -B are disposed on respective test cylinders  500 -A,  500 -B, which hold respective specimens of concrete. Using methods and apparatus similar to those described above, each sensor patch system  400  obtains measurements related to a respective specimen of concrete. Each sensor patch system  400  transmits measurement data to master database module  635  via local gateway  683  and network  605 . For example, each sensor patch system  400  may transmit measurement data wirelessly to local gateway  683 , which transmits the measurement data to master database module  635  via network  605 . Each sensor patch system  400  may also transmit an identifier uniquely identifying itself. For example, an RFID tag embedded in each sensor patch  400  may transmit identification information. Communication system  660  may include any number of sensor patch systems attached to respective test cylinders. 
     In one embodiment, multiple sensor patch systems  400  may be located at a single location (e.g., a single construction site). In another embodiment, multiple sensor patch systems  400  may be located at multiple locations (e.g., at multiple construction sites across large geographical areas such as States and countries). 
     Communication system  660  also includes a user device  690 , which may be a personal computer, laptop device, tablet device, cell phone, or other processing device which is located at a construction site and used by a technician at the site. User device  690  may communicate with network  605 , with local gateway  683 , and/or with other devices within communication system  660 . 
     Master database module  635  receives measurement data from one or more sensor patch systems  400  and may analyze the measurement data. In the illustrative embodiment, master database module  635  transmits the measurement data to prediction manager  640  (or otherwise makes the data available to prediction manager  640 ). Prediction manager  640  may generate predictions concerning the behavior of one or more concrete specimens. For example, prediction manager  640  may receive temperature, humidity, and/or location data from sensor patch system  400 -A and, based on the measurement data, generate predictions regarding the water-to-cementitious ratio, durability, strength, slump, maturity, etc., of the concrete specimen in cylinder  500 -A. Similarly, for example, prediction manager  640  may receive temperature, humidity, and/or location data from sensor patch system  400 -B and, based on the measurement data, generate prediction data regarding the water-to-cementitious ratio, durability, strength, slump, maturity, etc., of the concrete specimen in cylinder  500 -B. In one embodiment, the measurement data received by master database module  635  is provided to a real-time model to project setting behavior and strength for the entire batch of concrete. In another embodiment, the measurement data is continually subject to statistical analysis to generate real-time projections, control charts, etc. Master database module  635  may store the prediction data in cloud storage  670 . For example, prediction data may be stored in a database. Other data structures may be used to store prediction data. 
     In an embodiment, all measured data are stored and consolidated in a cloud database, and then the prediction manager  640  accesses the data, and by using scientific, technological, statistical, data mining, or neural network algorithms, provides the needed strength, maturity, form scheduling, and alarming projections and actions. 
     In one embodiment, master database module  635  may transmit measurement data and/or prediction information relating to water-to-cementitious ratio, durability, strength, slump, maturity, etc. to a user device such as user device  690  to enable a technician to access and view the information. For example, user device  690  may display measurement data and/or prediction data on a web page, or in another format. 
     In one embodiment, cloud storage  670  may comprise a cloud storage system. Data obtained by sensor patch system  400  may be transmitted to and saved in cloud storage  670  in real-time. A cloud implementation such as that illustrated by  FIG.  6 B  may allow data from projects in multiple regions or multiple countries to be auto-consolidated in a single database. 
     Suppose, then, that concrete is poured into cylinders  500 -A and  500 -B. Sensor patch systems  400 -A and  400 -B may obtain temperature and humidity measurements, and the data may be used to generate predictions for certain performance characteristics of the concrete in the cylinders. 
       FIG.  7    is a flowchart of a method in accordance with an embodiment. At step  710 , a sensor patch is attached to the side of a concrete test cylinder. For example, in the illustrative embodiment of  FIG.  6 B , sensor patch  400 -A is attached to test cylinder  500 -A. After sensor patch  400 -A is attached, the sensor patch obtains temperature and humidity measurements. 
     At step  720 , temperature and humidity measurements are received from the sensor patch. Sensor patch  400 -A transmits the measurements to master database module  635 . Master database module  635  receives the temperature and humidity measurements and transmits the data to prediction manager  640 . 
     At step  730 , predictions of maturity and strength of the concrete are generated based on the temperature and humidity measurements. Thus, prediction manager  640  generates predictions of maturity and strength for the concrete in test cylinder  500 -A, based on the temperature and humidity measurements obtained by sensor patch  400 -A. 
     Maturity is obtained by measuring concrete temperature versus time by applying ASTM C74 formulae. No matter what the field temperature profile, M expresses the curing age of concrete as an equivalent at a standard curing temperature such as 20 dC. 
     For each concrete class of given mix design, under lab or field conditions, a Strength versus M curve is established. 
     Accordingly, if the field clock time age (time since concrete was poured+transportation time) is for instance 50 hrs, one can convert to an M age of, for example, 32 hrs, and look up the strength. 
     Blocks  731  and  734  relate to treatment of field cylinders. To measure quality, field test cylinders are taken at concrete discharge or pour locations (for instance at pump discharge, on the 10 th  floor). The field tests must not be moved until concrete is strong enough to avoid damage, per ASTM and many other specifications. If moved prematurely, the tests will break low (since the cylinder could have crack during transportation), and are invalid, or disputes could occur between the testing lab, contractor, owner, and concrete vendor. 
     Blocks  732  and  733  relate to quality determination. Quality is usually evaluated by determining cylinder compressive strength at 28 M days, also sometimes at 7 M days or even 1 to 2 M days. The discussed approach will allow quality determination at any age by reference to current field and historical data on the basis of strength. If a closed loop process is being used, then mixture proportions for the test cylinders would be known, and converted to W/Cm ratio and strength by reference to calibration data. 
     Blocks  735 - 739  relate to form removal scheduling and actions. Measurements obtained from a sensor patch that are transmitted to a remote database, can provide concrete quality data-driven scheduling for form removal, and thereby allow for more efficient construction scheduling. A filed cylinder is used to develop Strength−M field calibration. In one embodiment, a sensor patch disposed on formwork will measure M-form, and thereby determine if concrete strength is such that the formwork could be stripped. If the answer to form stripping is negative, then the scheduling will be adjusted, but also action will be taken so as to maintain construction speed. Actions could include switching to stronger, faster setting concrete, using insulated formwork, erecting wind barriers, adding accelerating chemicals, etc. The data obtained by a sensor patch could also result in the reverse situation, namely that concrete sets too fast, and its setting and strength gain rate may need to be slowed down so as to make it constructible. 
     Advantageously, apparatus, systems, and methods described herein will increase concrete testing and quality management efficiency, and improve quality through automated real time data, that are auto-saved to remote databases and allow for full transparency. Apparatus, systems, and methods described herein make possible a more efficient construction process and construction rate by enabling a data-driven form removal scheduling approach. Self-evidently, when planning and scheduling concrete construction, the scheduling can best occur if concrete strength at early and later ages are known. This is particularly important during the construction process itself. Apparatus, systems, and methods described herein create the needed data automatically to schedule and make form stripping decisions on the basis of measurements, and not just past experience and guesswork. 
       FIG.  8    includes a graph showing observed temperature over time measured after a concrete mixture has been poured into a test cylinder. Graph  800  includes five sets of temperature measurements  820 -A,  820 -B,  820 -C,  820 -D, and  820 -E, each reflecting temperature of concrete in a test cylinder. The observed measurements show that after the concrete mixture is poured into the test cylinder, temperature begins at an initial temperature, rises from an initial temperature to a maximum (such as point  870 ), and then gradually decreases. In other examples, a specimen of a concrete mixture may demonstrate a different temperature profile. Advantageously, knowledge of the temperature profile associated with a particular specimen of concrete can be used to improve predictions of other characteristics of the concrete, such as strength, maturity, etc. 
     In various embodiments, the method steps described herein, including the method steps described in  FIG.  7   , may be performed in an order different from the particular order described or shown. In other embodiments, other steps may be provided, or steps may be eliminated, from the described methods. 
     Systems, apparatus, and methods described herein may be implemented using digital circuitry, or using one or more computers using well-known computer processors, memory units, storage devices, computer software, and other components. Typically, a computer includes a processor for executing instructions and one or more memories for storing instructions and data. A computer may also include, or be coupled to, one or more mass storage devices, such as one or more magnetic disks, internal hard disks and removable disks, magneto-optical disks, optical disks, etc. 
     Systems, apparatus, and methods described herein may be implemented using computers operating in a client-server relationship. Typically, in such a system, the client computers are located remotely from the server computer and interact via a network. The client-server relationship may be defined and controlled by computer programs running on the respective client and server computers. 
     Systems, apparatus, and methods described herein may be used within a network-based cloud computing system. In such a network-based cloud computing system, a server or another processor that is connected to a network communicates with one or more client computers via a network. A client computer may communicate with the server via a network browser application residing and operating on the client computer, for example. A client computer may store data on the server and access the data via the network. A client computer may transmit requests for data, or requests for online services, to the server via the network. The server may perform requested services and provide data to the client computer(s). The server may also transmit data adapted to cause a client computer to perform a specified function, e.g., to perform a calculation, to display specified data on a screen, etc. 
     Systems, apparatus, and methods described herein may be implemented using a computer program product tangibly embodied in an information carrier, e.g., in a non-transitory machine-readable storage device, for execution by a programmable processor; and the method steps described herein, including one or more of the steps of  FIG.  7   , may be implemented using one or more computer programs that are executable by such a processor. A computer program is a set of computer program instructions that can be used, directly or indirectly, in a computer to perform a certain activity or bring about a certain result. A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. 
     A high-level block diagram of an exemplary computer that may be used to implement systems, apparatus and methods described herein is illustrated in  FIG.  9   . Computer  900  includes a processor  901  operatively coupled to a data storage device  902  and a memory  903 . Processor  901  controls the overall operation of computer  900  by executing computer program instructions that define such operations. The computer program instructions may be stored in data storage device  902 , or other computer readable medium, and loaded into memory  903  when execution of the computer program instructions is desired. Thus, the method steps of  FIG.  7    can be defined by the computer program instructions stored in memory  903  and/or data storage device  902  and controlled by the processor  901  executing the computer program instructions. For example, the computer program instructions can be implemented as computer executable code programmed by one skilled in the art to perform an algorithm defined by the method steps of  FIG.  7   . Accordingly, by executing the computer program instructions, the processor  901  executes an algorithm defined by the method steps of  FIG.  7   . Computer  900  also includes one or more network interfaces  904  for communicating with other devices via a network. Computer  900  also includes one or more input/output devices  905  that enable user interaction with computer  900  (e.g., display, keyboard, mouse, speakers, buttons, etc.). 
     Processor  901  may include both general and special purpose microprocessors, and may be the sole processor or one of multiple processors of computer  900 . Processor  901  may include one or more central processing units (CPUs), for example. Processor  901 , data storage device  902 , and/or memory  903  may include, be supplemented by, or incorporated in, one or more application-specific integrated circuits (ASICs) and/or one or more field programmable gate arrays (FPGAs). 
     Data storage device  902  and memory  903  each include a tangible non-transitory computer readable storage medium. Data storage device  902 , and memory  903 , may each include high-speed random access memory, such as dynamic random access memory (DRAM), static random access memory (SRAM), double data rate synchronous dynamic random access memory (DDR RAM), or other random access solid state memory devices, and may include non-volatile memory, such as one or more magnetic disk storage devices such as internal hard disks and removable disks, magneto-optical disk storage devices, optical disk storage devices, flash memory devices, semiconductor memory devices, such as erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM), digital versatile disc read-only memory (DVD-ROM) disks, or other non-volatile solid state storage devices. 
     Input/output devices  905  may include peripherals, such as a printer, scanner, display screen, etc. For example, input/output devices  905  may include a display device such as a cathode ray tube (CRT) or liquid crystal display (LCD) monitor for displaying information to the user, a keyboard, and a pointing device such as a mouse or a trackball by which the user can provide input to computer  900 . 
     Any or all of the systems and apparatus discussed herein, including sensor patch  200 , sensor patch  400 , communication device  297 , computer  618 , master database module  635 , prediction manager  640 , cloud storage  670 , local gateway  683 , local storage  688 , and user device  690 , and components thereof, may be implemented using a computer such as computer  900 . 
     One skilled in the art will recognize that an implementation of an actual computer or computer system may have other structures and may contain other components as well, and that  FIG.  9    is a high-level representation of some of the components of such a computer for illustrative purposes. 
     In other embodiments, other methods and apparatus may be used to place a temperature sensor, a humidity sensor, and/or other sensors in contact with or in proximity to a concrete test cylinder in order to obtain temperature measurements, humidity measurements, etc. for the purpose of predicting a performance characteristic of a specimen of concrete inside the cylinder. 
     For example,  FIG.  10 A  shows a sensing system  1000  in accordance with another embodiment. Sensing system  1000  includes a cylindrical container  1020  with an open top, and a pocket  1028 . Pocket  1028  is disposed on a wall of container  1000 . 
       FIG.  10 B  shows a cross-section of container  1020  (of sensing system  1000 ) and of pocket  1028  in accordance with an embodiment. Pocket  1028  is constructed as an integral part of container  1020 . Pocket  1028  includes an enclosed volume  1040 . A plurality of holes  1023  are located in the interior portion of wall  1020  and connect volume  1040  with the interior space of container  1020 . 
     A temperature sensor  1065  is disposed within volume  1040 . Advantageously, holes  1023  allow an exchange of heat between container  1020  and volume  1028 , enabling temperature sensor  1065  to obtain temperature measurements associated with a specimen of concrete contained in container  1020 . 
       FIG.  10 C  shows a top view of sensing system  1000  in accordance with an embodiment. A capillary needle  1030  is disposed on the bottom surface of container  1020 . Capillary needle  1030  projects upward from the bottom surface of container  1020 . Capillary needle connects to a humidity sensor. 
     In accordance with an embodiment illustrated in  FIG.  11 A , container  1020  is adapted to receive a concrete test cylinder  1100 .  FIG.  11 B  shows concrete test cylinder  1100  placed in sensing system  1000 . When test cylinder  1100  is lowered into cylinder  1020 , capillary needle  1030  penetrates through the bottom surface of test cylinder  1100 . In one embodiment, a user pushes down on test cylinder  1100  to cause capillary needle  1030  to penetrate through the material of the test cylinder, effectively creating a hole in the material. In another embodiment, as concrete is poured into test cylinder  1100 , the weight of the concrete causes test cylinder  1100  to push down on capillary needle, causing capillary needle  1030  to penetrate through the material of the test cylinder, effectively creating a hole in the material. As shown in  FIG.  11 B , capillary needle  1030  penetrates through the material of the bottom surface of test cylinder. In one embodiment, capillary needle  1030  may include a material (such as Gortex, for example) which prevents the concrete mixture from coming into contact with capillary needle  1030  but allows the passage of moisture to enable capillary needle to obtain humidity measurements. 
     After concrete is poured into concrete test cylinder  1100  and concrete test cylinder  1100  is placed into sensing system  1000 , temperature sensor  1065  begins to obtain temperature measurements, and capillary needle  1030  begins to obtain humidity measurements. In a manner similar to those discussed above, temperature and humidity measurements may be transmitted to a remote device and used to generate a prediction of a performance characteristic for the concrete  1190  in test cylinder  1100 . 
       FIGS.  12 A- 12 D  show a sensor patch in accordance with an embodiment.  FIG.  12 A  shows a first side of the sensor pouch.  FIG.  12 B  shows a second (opposite) side of the sensor patch.  FIG.  12 C  shows a side-view cross-section of the sensor patch.  FIG.  12 D  shows a top-view cross-section of the sensor patch. 
     Sensor patch  1200  is adapted to fit onto and conform to the convex shape of an outer wall of a concrete test cylinder. In particular, patch  1200  includes a side  1215  having a concave shape. A plurality of holes  1223  are disposed on concave side  1215 . The inside of sensor patch  1200  includes a volume  1240 . 
     In accordance with  FIGS.  13 A- 13 B , a temperature sensor  1365  is placed into sensor patch  1200 . Specifically, temperature sensor  1365  is disposed within volume  1240  inside sensor patch  1200 . In one embodiment, one side of sensor patch  1200  may be removed (by screws, etc.) to facilitate the placement of a temperature sensor therein. 
     Thus, in some embodiments, a sensor patch may include a housing (which includes the various sides of the sensor patch such as side  1215  in  FIG.  12 C ), and a cavity (such as volume  1240 ) defined within the housing. A temperature sensor and/or other sensors, transmitters, etc. may be disposed within the cavity. 
     In accordance with an embodiment, sensor patch  1200  is attached to the side of a concrete test cylinder.  FIG.  14 A  shows sensor patch  1200  attached to an outer surface of a concrete test cylinder  1400 . 
       FIG.  14 B  shows a cross-section of sensor patch  1200  and of concrete test cylinder  1400  in accordance with an embodiment. Concrete test cylinder  1400  holds a concrete mixture  1490 . Concave side  1215  of sensor patch  1200  is in contact with or proximate to an outer surface of test cylinder  1400 . Holes  1223  allow heat from test cylinder  1400  to penetrate into sensor patch  1200 , enabling temperature sensor  1365  to obtain temperature measurements. 
     After concrete is poured into concrete test cylinder  1400 , temperature sensor  1365  begins to obtain temperature measurements. In a manner similar to those discussed above, temperature measurements may be transmitted to a remote device and used to generate a prediction of a performance characteristic for the concrete  1490  in test cylinder  1400 . 
       FIG.  15    shows components of a sensor patch  1500  in accordance with another embodiment. Sensor patch  1500  includes a sensor enclosure body  1520 , a sensor device  1540 , and a cover  1560 . Sensor device  1540  is adapted to fit into an opening  1620  of sensor enclosure body  1520 . Cover  1560  fits onto an end of sensor enclosure body  1520 . When in place on sensor enclosure body  1520 , cover  1560  covers and protects sensor device  1540 . 
       FIGS.  16 A- 16 D  show a sensor patch in accordance with an embodiment.  FIG.  16 A  shows a top view of the sensor pouch.  FIG.  16 B  shows a side view of the sensor patch.  FIG.  16 C  shows a front view of the sensor patch.  FIG.  16 D  shows a side view cross-section of the sensor patch. 
     Referring to  FIG.  16 A , sensor enclosure body  1520  includes opening  1620 , an opening  1633 , and an opening  1635 . Opening  1620  is adapted to receive and hold sensor device  1540 . Sensor enclosure body  1520  has a side  1610  having a concave shape. Side  1610  of sensor enclosure body  1520  is adapted to fit onto and conform to the convex shape of an outer wall of a concrete test cylinder. Sensor enclosure body  1520  has a first dimension d 1  which may be, for example, between 0.5-1.5 inches, most preferably 1.08 inches. Sensor enclosure body  1520  has a second dimension d 2  which may be, for example, between 1.5-2.0 inches, most preferably 1.72 inches. 
     Referring to  FIG.  16 B , sensor enclosure body  1520  includes a connector  1650  disposed along the side of its structure opposite concave side  1610 . In one embodiment, the sensor patch is positioned against the outside surface of a cylinder that contains concrete. Connector  1650  is adapted to receive an element that holds the sensor patch in place. For example, connector  1650  may be an opening adapted to receive a cable, band, ring, etc. Alternatively, connector  1650  may be a hook, or other type of connector. For example, connector  1650  may hold a portion of a band or ring (e.g., a portion of an O-ring that circles a cylinder). For example, a band or ring may exert pressure to press the sensor patch against the cylinder or may hold the sensor patch in place in another manner. Sensor enclosure body  1520  has a third dimension d 3  which may be, for example, between 1.5 and 2.0 inches, most preferably 1.71 inches. Sensor enclosure body  1520  has a fourth dimension d 4  which may be, for example, between 1.5 and 2.0 inches, most preferably 0.77 inches. 
     Referring to  FIG.  16 C , sensor enclosure body  1520  also includes a plurality of holes  1664  disposed on concave side  1610 . Holes  1664  allow air to pass between the interior of sensor enclosure body  1520  to the exterior of sensor enclosure body  1520 . 
     Referring to  FIG.  16 D , sensor enclosure body  1520  includes an internal volume  1675  accessible via opening  1620 . Volume  1675  is adapted to hold sensor device  1540 . Sensor enclosure body  1520  also includes a volume  1678  accessible via opening  1633 . 
       FIGS.  17 A- 17 C  show cover  1560  in accordance with an embodiment.  FIG.  17 A  shows a bottom view of cover  1560 .  FIG.  17 B  shows a first side view of cover  1560 .  FIG.  17 C  shows a second side view of cover  1560 . 
     Referring to  FIG.  17 A , cover  1560  includes a first tab  1710  adapted to fit into opening  1620 , a second tab  1722  adapted to fit into opening  1635 , and a third tab  1724  adapted to fit into opening  1633 . Cover  1560  has a first dimension w 1 , which may be between 1.5-2.0 inches, most preferably 1.72 inches. 
     Referring to  FIG.  17 B , cover  1560  has a second dimension w 2 , which may be between 0.1-0.5 inches, most preferably 0.24 inches. Referring to  FIG.  17 C , cover  1560  has a third dimension w 3 , which may be between 0.5-1.0 inches, most preferably 0.77 inches. 
       FIG.  18    shows a sensor patch (including sensor enclosure body  1520 ) attached to the side of a test cylinder in accordance with an embodiment. Specifically, sensor enclosure body  1520  is attached to the surface of a side of a test cylinder  1820  by a ring  1830  that passes through connector  1650 . Ring  1830  is sufficiently tight to hold sensor enclosure body  1520  in place against the surface of test cylinder  1820 . 
     It has been observed that when a test cylinder and a sensor patch are used outdoors to test a specimen of concrete, the sensors within the sensor patch may be affected (e.g., heated) by solar radiation and other environmental factors, thereby causing measurements to be unreliable or inaccurate. There is a need for systems and methods to ensure that measurements made by sensors in a sensor patch are reliable and accurate under varying environmental conditions. 
       FIG.  19    shows a cylinder enclosure system in accordance with an embodiment. Enclosure system  1900  includes a cover  1910  and a base  1920 . Cover  1910  is a hollow cylinder having a closed top portion  1911  and a round side portion  1913 , and an open bottom  1915 . Base  1920  has an outer ring  1923  and an inner ring  1925 . Cover  1910  is adapted to fit into outer ring  1923 . 
     In one embodiment shown in  FIG.  20   , inner ring  1925  of base  1920  is adapted to receive and hold a standard test cylinder. Therefore, in one embodiment, inner ring  1925  has a diameter of 4 inches and is adapted to receive a 4×8 test cylinder. In another embodiment, inner ring  1925  has a diameter of 6 inches and is adapted to receive a 6×12 test cylinder. Cover  1910  is adapted to cover and enclose a standard test cylinder. Accordingly, in one embodiment, cover  1910  is adapted to cover and enclose a 4×8 test cylinder. For example, cover  1910  may have dimensions of 6×12 inches, sufficient to cover a 4×8 test cylinder. Other dimensions may be used. 
     In another embodiment, cover  1910  is adapted to cover and enclose a 6×12 test cylinder. For example, cover  1910  may have dimensions of 9×18 inches, sufficient to cover a 6×12 test cylinder. Other dimensions may be used. 
     In one embodiment, cover  1910  and base  1920  are made from a plastic material. Other materials may be used. In one embodiment, the surface of cover  1900  includes a reflective material, such as foil, reflective paint, reflective sprayed material, etc. Cover  1900  may have a light-colored surface, such as white or silver. 
     In one embodiment, a standard test cylinder is placed in cylinder enclosure system  1900 .  FIGS.  20 - 22    illustrate a method of placing a test cylinder into cylinder enclosure system  1900  in accordance with an embodiment. Referring to  FIG.  20   , a test cylinder  2050 , including a cap  2055  and a sensor patch (illustrated by sensor enclosure body  1520 ) containing a sensor device, and which holds a specimen of concrete  2062 , is placed into inner ring  1925  of base  1920 . Referring to  FIG.  21   , cover  1910  is placed over cylinder  2050  and cap  2055 , and fits into outer ring  1923  of base  1920 . 
     Referring to  FIG.  22   , test cylinder  2050  (with cap  2655  and sensor enclosure body  1520 ) may remain within cylinder enclosure system  1900  as long as desired. For example, after a specimen of concrete is poured into test cylinder  2050  for the purpose of testing the concrete, the test cylinder may be placed into cylinder enclosure system  1900 . The cylinder enclosure system  1900  (with the test cylinder  2050  and sensor enclosure body  1520  inside) may then be placed outdoors for the duration of the test, for example. Advantageously, even in direct sunlight, cylinder enclosure system  1900  protects cylinder  2050 , sensor enclosure body  1520 , and the specimen of concrete  2062 , from the effects of solar radiation and other environmental factors. 
       FIG.  23    shows a cylinder enclosure system in accordance with another embodiment. System  2300  includes a cover  2310  and a base  2320 . A handle  2388  is attached to a top surface  2311  of cover  2310 . Two hooks  2391  are attached at the edges of top surface  2311  of cover  2310 . Two chains  2365  are attached to base  2320 . 
     In accordance with an embodiment, after a test cylinder is placed into cylinder enclosure system  2300 , in the manner described herein, cover  2310  is placed onto base  2320 , and chains  2365  are drawn up and attached to hooks  2391  on cover  2310 , as shown in  FIG.  24   . The chains secure cover  2310  on base  2320 . Once secured, cylinder enclosure system  2300  may be easily picked up by handles  2388  and transported from one location to a second location. 
     In accordance with other embodiments, a cylinder enclosure system may be closed and secured using other techniques and mechanisms. For example, the base of a cylinder enclosure system may contain a first set of threads (internal or external), and the cover of the cylinder enclosure system may contain a second set of threads adapted to engage with the first set of threads. Accordingly, the cover may be secured to the base by placed the threads together in a well-known manner and turning the cover so that the first threads engage with the second threads. 
     In accordance with another embodiment, a first test cylinder containing a concrete mixture is placed in a first cylinder enclosure system. A second test cylinder containing an inert substance having thermal characteristics similar to the concrete mixture is placed in a second cylinder enclosure system. For example, the inert substance may include copper, or dry concrete, or another substance. The first and second cylinder enclosure systems (with their respective test cylinders) are placed in a selected environment (such as at a selected field location at a construction site) for a predetermined period of time. Temperature measurements are obtained from both test cylinders at selected times while the concrete mixture in the first test cylinder dries. A first temperature profile associated with the concrete mixture and a second temperature measurement associated with the substance in the second test cylinder are determined based on the temperature measurements. One or more characteristics of the concrete mixture may be determined by comparing the first and second temperature profiles. For example, a heat maximum associated with the heat of hydration generated by the concrete mixture may be observed by subtracting the second temperature profile from the first temperature profile. Other characteristics of the concrete mixture may be determined in a similar manner. 
     In another embodiment, other mechanisms may be used to place a sensor on a concrete test cylinder, and the test cylinder may then be placed within a cylinder enclosure system such as cylinder enclosure system  2300 . For example, a sensor or sensor device may be placed in different location or a different position on or proximate a concrete test cylinder, and then the cylinder may be placed in a cylinder enclosure system. For example, in one embodiment, a cap is placed on a concrete test cylinder that holds a concrete mixture. The cap may cover and seal the top of the test cylinder, for example. One or more sensors such as a temperature sensor, a humidity sensor, etc., are attached to the cap. For example, one or more sensors may be disposed on an internal surface of the cap proximate the concrete mixture. The concrete test cylinder with the cap is placed in a cylinder enclosure system. While the test cylinder and cap are in the cylinder enclosure system, the sensor(s) obtain temperature measurements, humidity measurements, etc., and may transmit the data. A remote processor may receive the measurement data and determine a characteristic of the concrete mixture based on the data, as described herein. 
     The foregoing Detailed Description is to be understood as being in every respect illustrative and exemplary, but not restrictive, and the scope of the invention disclosed herein is not to be determined from the Detailed Description, but rather from the claims as interpreted according to the full breadth permitted by the patent laws. It is to be understood that the embodiments shown and described herein are only illustrative of the principles of the present invention and that various modifications may be implemented by those skilled in the art without departing from the scope and spirit of the invention. Those skilled in the art could implement various other feature combinations without departing from the scope and spirit of the invention.