PLC-based design of monitoring system for ICT-integrated vertical fish farm

Power line communication

The commercialized PLC systems exert a speed up to 1 Gbps for both home and multimedia use [2–6]. However, the problem of noise due to electromagnetic waves still remains as a major demerit of these systems such that in most cases, transformers are used to solve the problem. The PLC technology is being adopted the IoT-oriented homes to control household appliances by using telephone or power lines. The major advantage of using this technology is that not much additional works are required to install the PLC system, which means no extra installation of communication circuits. Two of the exemplar components in such a system are the attachable/external PLC modems developed by Energy Korea Co., Ltd. (ROK) for the watt-hour meters and the PLC-based broadcast module developed by Korea Electro Technology Research Institute. Both products demonstrate convenient and accurate performances. There is no doubt that the PLC technology will be used more widely in the future but the problem of noise has not been solved completely yet. Therefore, use of RUDP in a transport layer was proposed in this study to increase reliability of communications by reducing noise generation.

Reliable user datagram protocol

Sum of the time-derivatives against received packet volume when RUDP is used.

Although TCP (Transmission Control Protocol) has the best speed, UDP (User Datagram Protocol) is used often instead as TCP has some vulnerability in security. The speed of RUDP has been improved recently so that RUDP has been proposed to compensate noise-oriented transmission losses.

Vertical farm

“Vertical Farm” is an alternative farming system invented by Prof. Dickson Despommier [10–14], Columbia University in 1999 [10] to solve the problems of shortages of food and farmlands. This system allows farmers to grow their products regardless of weather conditions by controlling lights, water, temperature and humidity. It’s often referred to as a “Plant Farm” as well. For the agricultural sector, the test bed experiments were completed in Japan, US and Europe, where some of their firms have entered into the business stages whereas the livestock sector is actively studying the system together with some pharmaceutical companies.

Figure 1 shows an example of vertical farm. This paper considers selection of a suitable site. In theory, Prof. Despommier’s system [10–14] can crop thirty times a year in the city area and grow plants as much as one needs no matter what the weather conditions are (e.g., droughts, floods and typhoons, etc.).

This “Future Farming” in times of abnormal climate changes uses LED lights instead of sunlight and sprinkles nutrient-mixed sprays on the roots instead of soaking them in the water. According to the simulations, it is possible to grow enough foodstuffs to feed around fifty thousand people with a thirty-story farm.

Employee monitoring

The farm management can monitor the performance of their employees by providing the personal tags for them. The tags were originally developed for a theft-prevention purpose but they have other functions as well. For example, they can be used to track whereabouts of their employees, how they are performing their tasks, or what are their attendances are. While the management can have such advantages, employees will also have some benefits as well. That is, they can be warned of emergencies, check their working days or absences conveniently to calculate their wages. This can reduce monetary complaints and also secures the safety of employees. A part of technologies used for the proposed system was originally designed for the electronic auto-lock system where wireless AP (Access Point). Considering the reliability and efficiency of the system, RUDP was used as a transfer protocol. Both C and C++ languages were used for coding while Java was used for the implementation. One of the distinctive features of this system is that the communications between equipments are established solely on a power line(s) so that additional device (or circuits) installation works can be minimized. Now that almost all the fish farms can use the electric power supplied by the Korean Electric Power Corp. (KEPCO), they can also construct an individual PLC network conveniently without much cost. Figure 4 describes the main algorithm of this employee monitoring system.

Embedding the employee monitoring algorithm in a positioning system will allow convenient monitoring of individual employee’s performance while preventing accidents and thefts in the farms. At the same time, such a system can secure employees safety by assessing present danger or anticipating imminent disasters and informing them to take some adequate preventive measures. System’s monitoring process is described in Fig. 5.

As the population in most fishing villages is aging rapidly, most of the workers in the nearby fish farms consist of relatively old people who could fall into some dangerous situations more easily than the younger workers as they lack endurance. This is true especially during the summer time when the number of heat-oriented illnesses usually increases. The system with the proposed algorithm can prevent such indents as it can routinely check their movements. Once the system determines that a worker is not shifting his/her present position for a certain period of time, it assumes that he/she is either taking a rest or in danger.

Full-grown marine products at fish farms are shipped out to markets seasonally to get better profits but these periods could be the most vulnerable time as the major portion of thefts or accidents occur during these periods, resulting in a great loss for the farmers. The traditional theft prevention systems used by the farmers require expensive installation costs as they include many system devices or equipments and can be installed by the experts only. On the other hand, the PLC-based systems like the one proposed in this study require a relatively small installation cost and offer better performances. The authorized employee (or visitor) tags allow farm managers to check their employees’ access situations so that they will be informed of accesses of ones with unauthorized tags immediately through smart phones or other portable devices. Then, the precautionary measures can be taken to prevent possible theft.

Farming environment monitoring

Various factors must be balanced within an appropriate environment when culturing marine products. For the ocean cage-fishing farms, seawater temperatures, weathers, currents and tides should be considered while for the land-based farms, water temperatures, pH and salinity are the important factors. Especially the latter is often influenced by the temperature changes caused by nearby factories who use seawater as a coolant or by the changes in salinity within the tanks resulting from salty substances carried from the seaside, leading to mass mortality of fishes and shells. Since these changes cannot be recognized visually, it is difficult for the small and medium-sized fish farms to check them. Even a little change can present much risk and if they accumulate, a greater damage can be expected [1]. Figure 6 shows a farming environment monitoring process.

However, it is possible to check these changes immediately with the proposed application and by setting the checking categories to issue an alarm, farmers will be able to prevent damages and reduce manpower for a monitoring task. At the same time, by creating a database for the fish diseases and intelligently operating the system, relevant information can be sent to nearby marine disease control center, the Ministry of maritime Affairs and Fisheries, or National Fisheries Research and Development Institute for speedy feedbacks to prevent damages beforehand.

Management of photoperiod

Spawning and cultivating fishes can be controlled by adjusting the water temperatures and photoperiods. It is possible for the fishes to spawn and grow faster with a “long-day treatment (lengthening of photoperiod with artificial lights)”, especially for the flatfish for which the photoperiod is more effective than the temperature. If the photoperiod can be controlled with an automatic light adjustment system through the application, the number of fishes will be multiplied much faster.

Aspects of energy and environmental conservation

Auxiliary batteries and solar cells

As always, typhoons during the summer are the major concern of fish farmers as power interruptions caused by them can be fatal to their farms. Even a short period of interruption can result in entire mortality within the farm so that farmers prepare for the emergency situations once a typhoon alert has been issued. To deal with such a situation, the auxiliary batteries, which can be charged at dawn and used in the daytime during which the same batteries can be re-charged through solar cells, can be considered. Farmers will be able to store the charged power within the batteries 24 h a day to get ready for unexpected or notified power interruptions to reducing damages [1]. Figure 7 shows auxiliary batteries and solar cells.

Controlling withdrawal period

Despite of current developments in the fish culturing technologies, using antibiotics for marine products is still unavoidable. Usually, the safety of these products is secured by making sure that they will be shipped out after their withdrawal time. Nevertheless, it is true that sometimes such a process is being ignored intentionally for the monetary purpose or by mistake as there are many antibiotics being used these days and their usages can be quite confusing, even with a periodical training. One of the distinctive features of the proposed system is that the contents of ‘A Guide to Medicines for Marine Products’ (Korea National Fisheries Research and Development Institute, 2016) are included in a system database as a reference so that the system recognizes what kind of a drug and how much of it has been administered and then notifies the user by alarm after its withdrawal time has passed. This function will surely improve the brand image of farmer’s products. The management of seawater temperature and the level of dissolved oxygen in the seawater is critical for the fish farms but the workers or even managers often forget to check these as they have other chores to attend. It is almost impossible for those workers in a small-sized farm to continuously check these two elements so that in many cases, accidents happen abruptly and the responses are usually late. Figure 8 shows a database design for controlling the withdrawal period.

The two most important elements for aquaculture, dissolved oxygen and temperature, should be consistently observed and managed but in many cases, employees at the site are unable to cope with emergency situations associated with these elements. Figure 9 shows a design of proposed Android application.

The menus in this application are Fish Farm Management, Access Control, Positioning, Withdrawal Period Checking and Auxiliary (Ancillary) Battery. The first category is used for the management of photoperiods and seawater elements such as Dissolved Oxygen (DO), pH and temperatures. Access Control monitors and controls farm accesses to prevent theft and accidents. Warnings will be sent to the user’s smartphone once an unauthorized person enters the farm. Positioning, which locates the positions of employees in real-time, can be used to issue a warning in times of emergencies or give some working orders. Withdrawal Period Checking informs the user the last day of the withdrawal period through alarm so that he/she can take further working steps. Finally, Auxiliary Battery lets the user to check remaining battery power so that he/she can recharge it or find an alternative power source to get ready for the emergencies when the farm’s power fails.

RFID/USN-based high-quality marine product production support system

Construction of this system started in 2008 for the cage-culturing farms nearby Tongyeong-city, Gyeongsannam-do prefecture, aiming to increase income of aquaculture farmers, merchandise globally competitive marine products, and improve consumer trust. The goal of this project was to convince consumers that what they are consuming is safe and reliable by utilizing the RFID/USN technology to perform an adequate production process management and establish a data linkage throughout entire process [24]. Figure 10 shows a fish attached with the product developed at that time.

Some major contents of the project included a USN-based production management system for the cage-culturing farms, RFID-based traceability management system for fisheries port markets, integrated management system (portal site) for live-fish safety information, trace data, etc.

First, the USN-based cage-culturing production management system performs management of basic overall information of the farm in addition to arrival/shipment information management for both young and full-grown fishes and monitoring of growth/development environments. Second, the RFID-based traceability management system manages production information, reseller’s inventories, transaction information of distributors, live-fish arrival/shipment/transport information. Finally, the integrated management system (portal site) performs the activities such as business promotions, management of bulletin boards for consumers and users, as well as data linking with the Ministry of Food, Agriculture, Forestry and Fisheries (MIFAFF).

The major benefit for the distributors was an actual increase in their sales volume through demands of high-quality live fishes and transparent distribution process. Their reliability had improved with issuance of credible Country of Origin (COA) for the fishes shipped and it was possible for them to improve their earnings by using the statistics showing them accurate sales volumes and profits. Moreover, farmers were able to check an appropriate time and price by securing current sales and price status of entire nation’s port markets though the information linkage with the MIFAFF. Finally, the real-time availability of water temperature and dissolved oxygen of fish-delivery vehicles allowed them to minimize the loss during transportation.

From the resellers’ stance, their reliability and sales were improved by providing consumers with high-quality fishes with credible COA’s, as well as entire records in distribution process. Such trust-worthy information led to consumers’ trust while improving their earnings.

In general, it was expected that consumers would be able to enjoy a healthy diet as the proposed systems could minimize distribution of substandard fishes and offer accurate production/delivery information to promptly cope with crisis.

High-quality u-aquaculture support system in clean waters of Jeju Island

This system, which was constructed in January of 2009 in Jeju Island, is to automatically collect and manage production information including manufacturing of mixed feeds, feeding process, etc. by using RFID/USN technology for the aquaculture industry. RFID tags are attached on the fishes to provide the same information to consumers. The system allows consumers to check the information with attached RFID tags. A real-name production system was implemented to provide production information to consumers and such a measure allowed consumers’ confidence on the Jeju-produced aquaculture products to be improved while securing industry’s competitiveness following the market-opening pressures from FTA and other trade agreements, promoting the image of clean Jeju globally [25]. Figure 11 shows the high-quality u-Aquaculture support system in clean waters of Jeju Island. Figure 12 shows monitoring tags.

Construction project of u-aquaculture farm in Tongyeong and Maritime Disaster response system

The u-IT pilot project was implemented for six aquaculture farms nearby Tongyeong-city in 2010. The project was comprised of tasks such as improvement of growth and development management system of existing RFID/USN-based high-quality production support system, construction of the farm-protection and emergency alarm service systems using CCTVs and intrusion detection sensors, and establishment of the disaster observation and response system by linking with it weather information and the real-time seawater pollution observation system.

Some of the major performances include improvement of farm management by securing farm’s operating information and monitoring theft and disaster events, establishment of disaster protection system with CCTVs, intrusion detection sensors along with the operation of bottom-layer seawater supply system, and construction of real-time monitoring and notification service system using smartphones.

This project was divided into five areas: First, object was to provide farmers with a distribution-model software package which allows an efficient and practical real-time monitoring of seawater environments. Second, the problems in existing growth and development management system were fixed through improvement of u-Farm growth management system software. Third, the real-time intrusion detection and theft prevention system was constructed to protect the standardized u-farms to give warnings. Fourth, by linking all the seawater environment information systems installed at the farms, the real-time farm disaster forecasting/warning system network was constructed. Finally, in order to respond to seawater pollutions, the systems were designed to provide the information regarding the low-layer seawater supply system (equipments) and the possibility of future crisis to the relevant authorities and the farmers.

The resulting effects of the introduced u-IT technology in this project can be found in four areas. First, computerization of farm management process led to the increase in efficiency. The task of managing aquaculture farms was considered as a 3D-work till then as it required much hard physical work and systematic management was not easy. Computerization and automation of management process largely contributed to the farmers’ earnings and work efficiency. Figure 13 shows construction project of u-Aquaculture farm in Tongyeong and maritime disaster response system.

Second, construction of an efficient and adaptable farm protection system was possible with a network of CCTVs, intrusion detection sensors, along with low-layer seawater supply equipments. By directly installing the protection system on the Fish farms, those facilities previously unprotected by existing systems were covered. Such a platform system can be utilized for the disasters occurring nearby waters. Much useful information (e.g., real-time images and sensor data) were provided to the relevant authorities and farmers through smartphones and websites in order for them to take some precautionary measures.

Third, the real-time provision of data including seawater temperatures, dissolved oxygen levels, weather information and tides were possible. Supplying such information vital to the farmers through software applications and internet sites in real-time was the first global attempt so that this research might be able to provide an important basis for future application development.

Fourth and last, introduction of the u-IT technology for the Fish farms is quite meaningful that the all the involved systems are ubiquitous. There have been various ubiquitous projects but implementing such a system on the cage-culturing farms is the first attempt and can be the first example that will be able to surmount regional and environmental limitations. Through the system, which the farmers and the relevant authorities can gain an easy access, the effects of u-Services can be maximized and the project described in this study will be exemplary to other researcher or farmers considering similar projects.