Abstract:
A groundwater profile monitoring system includes a groundwater sensor configured to sense a state of groundwater; a driving unit including a sensor cable to which the groundwater sensor is connected at one end thereof and configured to vertically move the groundwater sensor; a data logger configured to receive and store sensing information sensed by the groundwater sensor and transmit the sensing information to a designated server; and a power supply unit configured to produce electric power using solar energy and supply the produced electric power to the driving unit and the data logger. Since a profile material of vertical groundwater according to a depth of a tube well can be continuously collected by using one sensor, an accurate groundwater related material can be collected more efficiently.

Description:
BACKGROUND 
       [0001]    This application is directed to a groundwater profile monitoring system, and more particularly to a groundwater profile monitoring system for vertically monitoring information on the quality of groundwater by using a groundwater sensor. 
         [0002]    In general, a groundwater level of an aquifer near the coast periodically rises and falls due to a change of the tide of the ocean, and the salinity of seawater causes a difference in the density of groundwater and the seawater to penetrate under freshwater. 
         [0003]    Then, a dispersion zone appears at a border where freshwater and saltwater meet due to a dispersion of water, and a location, a shape, and a range of the mixing zone are determined by time, a form of an aquifer, an irrigation feature, and an amount of discharged groundwater. 
         [0004]    Also, since a coastal aquifer consists of several layers, a quality of groundwater needs to be periodically and vertically monitored so that a non-homogeneity of a medium, an uncertain form and location of a low permeability zone, and a penetration of seawater to groundwater due to their extension properties can be observed. 
         [0005]    Korea manages a total of more than 100 seawater penetration observing facilities to secure groundwater of coastal/island areas and prevent penetration of seawater in advance. 
         [0006]    Korea manages 131 seawater penetration observing facilities as of 2006, and since an aquifer having several layers is distributed under ground, the qualities of groundwater appear in a variety of ways according to depths. 
         [0007]    However, since the current monitoring system can observe a quality of water only at a point where it is initially installed, penetration of seawater cannot be properly observed. In particular, since fresh water and saltwater alternate at a place where impermeability layers and permeability layers are distributed to form several layers, causing severe non-homogeneity, it is inevitably necessary to vertically monitor them. 
       SUMMARY 
       [0008]    Accordingly, this disclosure and inventive concept herein have been developed to solve the above-mentioned problems occurring with conventional approaches, and an aspect of this disclosure provides a groundwater profile monitoring system which can collect a profile material regarding a quality of groundwater at a predetermined time interval and effectively observe a quality of groundwater at a location of an uneven aquifer where it is necessary to observe a penetration of seawater and a vertical quality of groundwater. 
         [0009]    In accordance with an embodiment, a groundwater profile monitoring system includes a groundwater sensor configured to sense a state of groundwater; a driving unit including a sensor cable to which the groundwater sensor is connected at one end thereof and configured to vertically move the groundwater sensor; a data logger configured to receive and store sensing information sensed by the groundwater sensor and transmit the sensing information to a designated server; and a power supply unit configured to produce electric power using solar energy and supply the produced electric power to the driving unit and the data logger. 
         [0010]    The driving unit may include a winding part for winding the sensor cable, a winding motor configured to rotate the winding part, and a controller configured to control the winding motor. The controller may drive the winding motor at a predetermined time interval and move the groundwater sensor upward and downward. 
         [0011]    The driving unit may include: a cable guide configured to guide the sensor cable so that the sensor cable is uniformly wound on the winding part; a guide rail connected to the cable guide and configured to guide a movement path of the cable guide; a pair of feeding cables connected to opposite sides of the cable guides; and a pair of guide motors selectively driven by the controller and configured to pull the feeding cables respectively and move the cable guide to the right and to the left. 
         [0012]    A pair of movement restrictors disposed opposite to each other may be coupled to the guide rail such that a movement range of the cable guide is restricted by the movement restrictors. 
         [0013]    Each movement restrictor may include an approach detector configured to transmit a sensing signal when the cable guide approaches within a predetermined distance. The controller may receive the sensing signal to stop one of the guide motors which is being driven and drive the remaining guide motor, so as to allow the cable guide to move in a direction opposite to a travel direction of the cable guide. 
         [0014]    The movement restrictor may include a changeover switch contacting the cable guide to be operated. The controller may receive a contact signal of the changeover switch to stop one of the guide motors which is being driven and drive the remaining guide motor, so as to allow the cable guide to move in a direction opposite to a travel direction of the cable guide. 
         [0015]    The cable guide may include a depth measurer configured to measure a winding length of the sensor cable and calculate a depth of the groundwater sensor. 
         [0016]    According to an embodiment, since a profile material of vertical groundwater according to a depth of a tube well can be continuously collected by using one sensor, an accurate groundwater related material can be collected more efficiently. Further, since a separate power transmission system for managing the system is not required, the system can be easily constructed in an area where electric power cannot be supplied easily. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    The above and other aspects, features and advantages of this disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: 
           [0018]      FIG. 1  is a front view of a groundwater profile monitoring system according to an embodiment; 
           [0019]      FIG. 2  is a view illustrating a driving unit of the groundwater profile monitoring system according to an embodiment; 
           [0020]      FIG. 3  is a view illustrating a part of the driving unit of  FIG. 2 ; 
           [0021]      FIG. 4  is a side view illustrating the driving unit of  FIG. 2 ; 
           [0022]      FIG. 5  is a view for explaining a structure of a cable guide. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    Hereinafter, embodiments of this disclosure will be described with reference to the accompanying drawings. In the following description, the same elements will be designated by the same reference numerals although they are shown in different drawings. Further, in the following discussion, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of this disclosure rather unclear. While an embodiment of this disclosure will be described hereinbelow, it is apparent that the technical spirit of the inventive concept is not limited to the embodiment described, but may be properly carried out by those skilled in the art in light of the appended claims. 
         [0024]      FIG. 1  is a front view of a groundwater profile monitoring system according to an embodiment.  FIG. 2  is a view illustrating a driving unit of the groundwater profile monitoring system according to an embodiment. 
         [0025]    Hereinafter, the groundwater profile monitoring system  100  according to an embodiment of this disclosure will be described with reference to  FIGS. 1 and 2 . 
         [0026]    The groundwater profile monitoring system  100  according to an embodiment includes a driving unit  110 , a groundwater sensor  140 , a power supply unit  150 , and a data logger  160 . 
         [0027]    The driving unit  110  includes a sensor cable  118  to move the groundwater sensor  140  connected to one end of the sensor cable  118  vertically, i.e. in an upward/downward direction of  FIG. 1 . 
         [0028]    In more detail, the driving unit  110  includes a winding part  112  configured to be rotated about a shaft inserted into a center thereof to wind a cable  118  therearound and a winding motor  114  configured to rotate the winding part  112 . The winding part  112  and the winding motor  114  are supported by a support frame  116 . 
         [0029]    The driving unit  110  includes a controller  115  configured to control a driving interval and a rotating direction of the winding motor  114 . The controller  115  drives the winding motor  114  at a predetermined time interval to move the groundwater sensor  140  upward and downward. 
         [0030]    The groundwater sensor  140  senses a state of groundwater. In more detail, the groundwater sensor  140  collects information about a water level, a temperature, an electric conductivity, a TDS (Total Dissolved Solids), a DO (Dissolved Oxygen), etc. and transmits the information to the data logger  160 . 
         [0031]    Then, the groundwater sensor  140  may be set to sense states of the groundwater at a predetermined time interval, and preferably includes a wireless communication means for transmitting collected information to the data logger  160 . 
         [0032]    The groundwater sensor  140  may include its own depth sensor for measuring a depth of its location. In this case, a depth of the groundwater sensor  140  may be identified without using a below-described depth measurer  130 . 
         [0033]    The power supply unit  150  may be realized by a photovoltaic power generation means or a solar thermal power generation means for producing electric power using solar energy. Preferably, the power supply unit  150  is realized by a photovoltaic power or solar thermal power generation means including a capacitor. 
         [0034]    The power supply unit  150  supplies the produced electric power to parts, such as the driving unit  110  and the data logger  160 , which require electric power. 
         [0035]    When the power supply unit  150  is realized by an electric power generation unit which uses solar energy, the groundwater profile monitoring system  100  according to an embodiment may be easily installed even in an area having no electric facility and to which electric power cannot be supplied easily. 
         [0036]    The groundwater profile monitoring system  100  according to an embodiment drives the driving unit  110  and the data logger  160  at a predetermined time interval, significantly reducing power consumption. 
         [0037]    Accordingly, even when the power supply unit  150  is realized by a photovoltaic power or solar thermal power generation means showing a difference between amounts of generated electric power depending on a change in weather, electric power may be stably supplied to the parts to which electric power should be supplied by using the already generated and accumulated electric power. 
         [0038]    The data logger  160  receives sensing information sensed and collected by the groundwater sensor  140 , and transmits the sensing information to a server (not shown). 
         [0039]    The data logger  160  is configured to transmit and receive data to and from the groundwater sensor  140  and the server (not shown) through a wireless communication means. For example, the data logger  160  may include a CDMA (Code Division Multiple Access) modem to transmit and receive data using the CDMA modem. 
         [0040]    The data logger  160  is configured to transmit an emergency signal to a manager or a user through the CDMA modem when electric power of a predetermined level cannot be supplied or data cannot be smoothly transmitted or received due to a failure of a device which can be caused by lightning. 
         [0041]      FIG. 3  is a view illustrating a part of the driving unit of  FIG. 2 .  FIG. 4  is a side view illustrating the driving unit of  FIG. 2 .  FIG. 5  is a view for explaining a structure of a cable guide. 
         [0042]    The driving unit guides the sensor cable  118  so that the sensor cable  118  can be uniformly wound on the winding part  112  and prevents the sensor cable  118  from being intensively wound only on one side of the winding part  112 . To achieve this, the driving part  110  further includes a cable guide  120  and a unit for driving the cable guide  120 . 
         [0043]    Hereinafter, the cable guide  120  and the unit for driving the cable guide  120  will be described in detail with reference to  FIGS. 3 to 5 . 
         [0044]    The cable guide  120  includes a groove for preventing the sensor cable  118  from being separated from the cable guide  120  while moving to the right and to the left to guide a location where the sensor cable  118  is wound. 
         [0045]    As illustrated in  FIG. 5 , the cable guide  120  may have a form where a bearing is interposed between an inner race and an outer race, but also may have a form where an inner race is rotated by the sensor cable  118  and a feeding cable  126  is connected to an outer race. 
         [0046]    The cable guide  120  is moved to the right and to the left along an axial direction of the guide rail  122  while being connected to the guide rail  122 . Then, the guide rail  122  is coupled to and supported by the support frame  116  and disposed parallel to an axial direction of the winding part  112 . 
         [0047]    Feeding cables  126  are respectively connected to opposite side surfaces of the cable guide  120 , i.e. a left side surface and a right side surface of the cable guide  120  of  FIG. 3 . 
         [0048]    The feeding cables  126  are respectively pulled by a pair of guide motors  124  installed on the right and left sides of the groundwater profile monitoring system  100  respectively, so that the cable guide  120  can be moved to the right and to the left. 
         [0049]    Then, a pair of movement restrictors  128  disposed opposite to each other may be coupled to the guide rail  122 . 
         [0050]    The movement restrictors  128  prevent the cable guide  120  moved to the right and to the left along a guide rail  122  from being deviated from a winding range of the winding part  112 . That is, the movement range of the cable guide  120  is restricted by the movement restrictors  128 . 
         [0051]    The movement restrictors  128  are disposed at locations corresponding to the right and left sides in the winding part  112  which are spaces for winding the sensor cable  118 . 
         [0052]    Meanwhile, a pair of guide motors  124  for moving the cable guide  120  is selectively driven under the control of the controller  115 . 
         [0053]    To achieve this, the movement restrictor  128  includes an approach detector  130  configured to transmit a sensing signal to the controller  115  when the cable guide  120  approaches within a predetermined distance. 
         [0054]    When receiving the sensing signal, the controller  115  stops a guide motor  124  which is being driven and drives a guide motor  124  on an opposite side to allow the cable guide  120  to move in a direction opposite to its travel direction. 
         [0055]    For example, the right guide motor  124  remains stopped while the left guide motor  124  installed on the left side of  FIG. 2  is driven to pull the cable guide to the left. In this state, if the cable guide  120  continues to move to the left so that the approach detector  130  detects an approach of the cable guide  120 , the sensing signal is transmitted to the controller  115  and the controller  115  stops the left guide motor  124  which is being driven and drives the right guide motor  124 . If the right guide motor  124  is driven, the cable guide  120  is pulled and moved to the right. 
         [0056]    In this way, the cable guide  120  is reciprocally moved to the right and to the left to allow the sensor cable  118  to be uniformly wound on the winding part  112 . 
         [0057]    The movement restrictor  128  may include a changeover switch (not shown) contacting the cable guide  120  to be operated instead of the approach detector  130 , so that the guide motors  124  can be selectively driven by the controller  115  having received a contact signal of the changeover switch. 
         [0058]    Meanwhile, the cable guide  120  further includes a depth measurer  132  configured to measure a winding length of the sensor cable  118  and calculate a depth of the groundwater sensor  140  inserted into a tube well. 
         [0059]    The depth measurer  132  may be realized by equipment such as a unit having a reel contacting the sensor cable  118  to be rotated or an encoder. 
         [0060]    The depth information of the groundwater sensor  140  measured by the depth measurer  132  is transmitted to the data logger  160  through a wireless communication means installed in the depth measurer  132 . 
         [0061]      FIG. 6  illustrates an example of the groundwater sensor, and  FIG. 7  illustrates an example of the data logger. The groundwater sensor  140  and the data logger  160  may be realized by the products manufactured as shown. 
         [0062]    While the inventive concept has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Accordingly, the embodiments and accompanying drawings disclosed herein are not intended to restrict the technical spirit of the this disclosure, but are intended to help explain the inventive concept. The scope of this disclosure should be construed by the following claims and all the technical spirits corresponding the equivalents should be construed to fall within the scope of the inventive concept.