• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.1
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• pp.45-54
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• 2020

In this study, an automatic system for improving the working environment and increasing production efficiency of a laver aquaculture industry in Korea was developed by combining a hydraulic control system and a load cell in a current landing work of the laver. The improved gathering laver system allowed the automatic gathering process of the laver in the sea with the hydraulic control system connected to a cutting machine of the laver on the operating ship, which has been used for gathering the laver semi-automatically in a form of the traditional farming method. The transporting process of the laver from an operating ship to the land was improved as follows. A frame installed on the operating ship and the bag nets were designed and made to hold about 1,000 kg of the laver inside. The bag nets contain the laver on the improved operating ship were tied in knots and hooked on a crane using a load cell. The weight is measured immediately by lifting the bag nets through the load cell system. Weight information is communicated to the fishermen and successful bidders through the application. The advantages of the improved system can help fishermen to fish by improving their working environment and increasing production efficiency. The field survey to improve the landing operation of the laver aquaculture was conducted in Gangjin, Goheung, Shinan, Wando, Jindo, and Haenam in South Jeonnam Province. A total of 10 sites including Gunsan in Jeonbuk Province, Daebu Island in Ansan City, Jebu Island in Hwaseong City in Gyeonggi Province, and Seocheon in Chungnam Province were searched to collect data. Prototypes of the system were tested at the auction house of laver located in Goheung, where laver collection using hydraulic control and landing using road cell could be improved.

• International Journal of Railway
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• v.1 no.4
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• pp.149-156
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• 2008

During maintenance or construction works in or at the tracks of railways, high risks for passengers and railway staff, especially for the workers on the construction site exist. The high risks result out of the movement of rail vehicles, like trains or construction vehicles, which must be faced by using any available technical and operational technologies for securing them against the environment. Therefore, it is necessary to evaluate the level of protection continuously and to identify new and innovative methods and technologies for the protection of the gang (construction worker, machines and material). Especially on construction sites at line sections with two or more parallel tracks but also with single tracks, there are still a lot of incidents and accidents mostly with seriously injured persons or fatalities. These were mainly gang members that breach the railway-loading gage. By using proper warning or protection systems, the avoidance of such accidents must be achieved. The latest developments. in gang protection systems concern on the one hand fixed barriers in the middle between the construction site and the operated track and on the other hand construction vehicles equipped with automatic warning systems. The disadvantage of such protection methods is that the gang can be warned against an approaching train but a monitoring of the gang members cannot be performed. Only one part of a potential dangerous situation will be detected. If the gang members will overhear the acoustic warning signal of the security staff and the workers will not leave the danger zone in the track, the driver of the approaching train had no chance to react to the dangerous situation. An accident is often inevitable. While the detection of acoustic warning signals by the gang members working on a construction site is very difficult, the acoustical planning of an automatic warning system has to be designed for an acoustic short range level of one meter besides the construction vehicle. The decision about the use of today's technical warning system (fixed systems, automatic warning systems, etc.) must be geared to the technical feasibility and the level of safety which is needed. Criteria for decision guidance to block a track should be developed by danger estimation and economical variables. To realize the actual jurisdiction and to minimize the hazards of railway operations by the use of construction vehicles near the tracks further developments are needed. This means, that the warning systems have to be enhanced to systems for protection, which monitor the realization of the warning signal as a precondition for giving a movement authority to a train. This method can protect against accidents caused by predictable wrongdoing. The actual state of the art technique of using a collective warning combined with additional security staff is no longer acceptable. Therefore, the Institute of Transportation System of the German Aerospace Center in Braunschweig (Germany) will develop a gang warning and protection system based upon imaging methods, with optical sensors such as video in visible and invisible ranges, radar, laser, and other. The advantage of such a system based on the possibility to monitor both the gang itself and the railway-loading gauge either of the parallel track or of the same track still in use. By monitoring both situations, the system will be able to generate a warning message for the approaching train, that there are obstacles in the track, so that the train can be stopped to prevent an accident. And also the gang workers will be warned, while they breach their area.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.65 no.4
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• pp.298-302
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• 2016

Currently, logistics are in small quantities and in diverse forms, and the amounts are continuously increasing. Railway logistics however are losing their market share every year mainly due to low operation speed and loading time, which means the trucks are covering the most of the freights. In order to solve these situations, this paper proposed the high speed freight train as working multi-modality with other modes to make effective transshipment. The high speed freight train has maximum operation speed of 300km/h and electric power to run centralized power supply. There are large dual door system, bogie system covering fluctuating load of 15[ton], automatic loading device, ULD(unit load device) bed and ULD locking system in this freight rolling stock. We calculated the performance of powering and braking capacity for this train and proposed how many vehicles are composed of train set. The results in this paper can help to make a decision to define the technical specification of High-speed freight train for the efficiency of rail freight service.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.3 no.2
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• pp.113-119
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• 1999

The quality of the effluent from an activated sludge aeration tank can deteriorate when the substrate removal rate decreases due to an abrupt reduction in the DO concentration, which is affected by such operating conditions as the loading rate, temperature, wastewater composition, and so on. In this research, a DO control system that includes a PI (proportional-integral) controller/Hiraoka controller was developed and applied to a pilot-scale activated sludge process, then its acceptability was estimated. The applicability of the respiration rate to DO control was also estimated. The respiration rate indicated a variety of input organic loading rates, which is the main disturbance to the DO concentration in an aeration tank. When the influent concentration incrementally decreased and increased between CODcr 1,000 mg/l and 100 mg/l, the control system with a PI controller exhibited a good llperformance-the average DO concentrations were 2.00$\pm$0.14 mg/l and 1.88$\pm$0.15 mg/l (set value was 2.0 mg/l), respectively, and the settling time was just 10 minites. When the control system was operated for 4 days, the DO concentration was 1.99$\pm$0.18 mg/l and 32.6% of the air flowrate was saved. However, the fluctuations in the respiration rates and air flowrates were severe, which could be harmful to the stability of the biomass and mechanical stability of the blower. A possible approach to solve this problem may be the simultaneous control of the loading rate and DO concentration.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.657-663
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• 2004

The aims of this study are the characterization of runoff from nonpoint source, the analysis of the pollutant loads and an establishment of a management plan for nonpoint source of Okcheon. For this purpose the basin of the stream So-okcheon was selected to the investigated. During the period from May 29 to July 21 in 2003, the water automatic sampler system has been installed in Okkagkyo and parameters such as SS, COD, TOC, TP and TN were analyzed. The pollutants of nonpoint source seem to be washed out along the stream water in the beginning of rainfall, remain in water and cause the stream pollution. The runoffs during heavy rainfall, especially, much higher concentration of SS than those during dry period. With respect to the annual loading of pollutants of the nonpoint source, the COD was 124 ton/yr, TOC 396 ton/yr, TN 1,429 ton/yr and TP 4.2 ton/yr in the year 2002. With respect to the pollutants loading of the nonpoint source, the COD was 375 ton/yr(95% of the total COD loading of 394 ton/yr), TOC 844 ton/yr(96% of the tatal TOC loading of 876 ton/yr), TN 1,985 ton/yr(96% of the total TN loading of 2,062 ton/yr) and TP 37.1 ton/yr(92% of the total TP loading of 40.3 ton/yr) in the year 2003.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1999.10a
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• pp.363-369
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• 1999

In these days, there are a lot of studies in the port automation, for example, unmanned container trasporter, unmanned gantry crain, and automatic terminal operation systems and so on. In terms of loading and unloading equipments. we can consider container transporter. This paper describes the automatic control for the UCT(unmanned container transporter), especially steering control systems. UCT is now operated on ECT port in Netherland and tested on PSA ports in Singapore. So we present a design on the controller using neural network PID(NNPID) controller to control the steering system and we use the neural network self-tuner to tune the PID parameters. The computer simulations show that our proposed controller has better performances than those of the other.

• Journal of Computational Design and Engineering
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• v.1 no.2
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• pp.140-151
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• 2014

Storing, and the loading and unloading of materials at production sites in the manufacturing sector for mass production is a critical problem that affects various aspects: the layout of the factory, line-side space, logistics, workers' work paths and ease of work, automatic procurement of components, and transfer and supply. Traditionally, the nesting problem has been an issue to improve the efficiency of raw materials; further, research into mainly 2D optimization has progressed. Also, recently, research into the expanded usage of 3D models to implement packing optimization has been actively carried out. Nevertheless, packing algorithms using 3D models are not widely used in practice, due to the large decrease in efficiency, owing to the complexity and excessive computational time. In this paper, the problem of efficiently loading and unloading freeform 3D objects into a given container has been solved, by considering the 3D form, ease of loading and unloading, and packing density. For this reason, a Group Packing Approach for workers has been developed, by using analyzed truck packing work patterns and Group Technology, which is to enhance the efficiency of storage in the manufacturing sector. Also, an algorithm for 3D packing has been developed, and implemented in a commercial 3D CAD modeling system. The 3D packing method consists of a grouping algorithm, a sequencing algorithm, an orientating algorithm, and a loading algorithm. These algorithms concern the respective aspects: the packing order, orientation decisions of parts, collision checking among parts and processing, position decisions of parts, efficiency verification, and loading and unloading simulation. Storage optimization and examination of the ease of loading and unloading are possible, and various kinds of engineering analysis, such as work performance analysis, are facilitated through the intelligent 3D packing method developed in this paper, by using the results of the 3D model.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1309-1311
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• 2003

Communication based train control system is applied regularly worldwide. And this system may be used in domestic soon. Communication based train control system does not depend on conventional track circuit. Therefore, position and distance control of train to prevent collision with loading train may become important safety factor. This paper developed collision avoidance algorithm to control trains of several units efficiently for this. In developing a collision avoidance algorithm, it is desirable to avoid the need for additional system. Additional system restricts the development of the algorithm by limiting the effectiveness of the algorithm to only those areas where the additional system can be afforded and has been installed.

• Journal of the Korean Society for Heat Treatment
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• v.13 no.1
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• pp.10-15
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• 2000

Evaluation of long term stability of the Brinell standard hardness tester was carried out to secure its application as a national standard in Brinell hardness. Accuracy and repeatability in load application were tested through evaluating errors in hardness measurement of certified reference blocks. All of those requirements in KS as well as ISO specifications were satisfied by this standard hardness tester. In addition to this, long term stability test of automatic indentation measurement system was carried out. The scattering range was almost the same with its error range. To figure out an optimum test condition for better repeatability and long term stability, the effect of load variation, load application speed and time have been studied using orthogonal array experimental plan. It was found that the best combination is $30{\mu}m/s$ of load application speed and 25 seconds of load application time.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.492-496
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• 1987

The testing philosophy and control schemes are investigated and applied to construct the Automatic Microwave Leakage Inspection System (AMLIS) . AMLIS is consists of three major parts such as Material Handling Mechanism, Fine Positioning Mechanism and Scanning Mechanism. The material Handling unit is designed to perform loading and unloading microwave oven onto the testing point by pneumatic cylinder and vacuum pump. The Fine positioning part includes X-Y-.THETA. table and distance sensing equipment. The scanning part is composed of five SCARA robots, which traverse X-Y-Z catesian coordinates respectively. The leakage testing probes are placed at the end of this each robot then the path and speed are both controlled via microprocessors. A performance test of this system combined with electric parts and software is done and the basic major function of system are accomplished.