• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.883-889
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• 2021

The South Korean fishing industry is experiencing a rapid growth owing to an increase in its leisure-fishing population. Consequently, fishing boats weighing 9-10 [ton] have also been increasing. Current fishing boats operate their essential equipment by switching their engines with batteries to reduce the cost of gas and engine noise. However, stranding incidents have been increasingly recorded annually, in which boats fail to start owing to discharged batteries, and these incidents can lead to serious casualties. This study proposes the installation of a solar auxiliary power system to safeguard fishing boats, particularly those weighing between 9-10 [ton]. The feasibility of securing space for the solar auxiliary power of boats under consideration was verified. To examine the application of solar power, this study calculates the load necessary to operate it for fishing and models such a system using an electricity analysis program The modeled system, which applies the monthly horizontal solar insolation, validated the adoption of a solar auxiliary power in fishing boats.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2992-2994
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• 2000

In cope with insufficient agricultural labor and requirement of high quality product Hydroponics is a really good method. It makes the high density agriculture possible and all the growing environments controllable. So its research is so much progressing to maximize the quantity and quality of farm products. Furthermore, the big progress, in the research of a future agriculture. is systematically conducted for the automatic controlled system. In this paper, a practical automatic control cultivation system is implemented. To automatically control and optimize the very nonlinear and time-varying growth of farm products, a hybrid strategy(FECA: Fuzzy Expertized Control Algorithm) is proposed which serially combines a fuzzy expert system with the fuzzy logic control. The fuzzy expert system (FMES: Fuzzy Model-based Expert System) is intended to overcome the non-linearity of the growth of farm products. The part of fuzzy controller is incorporated to solve the time-variance of the growth of farm products. Finally. the efficiency and the effectiveness of the implemented agricultural automation system is presented through the cultivation results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.1
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• pp.88-94
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• 2021

Currently, the Busan cooperative fish market follows a traditional market style. This study first investigates the current conditions and environment of the market, and to modernize the market, it proposes a new automatic unloading system based on the benchmark of Namhae Suhyup. In this system, a Korean-type suction fish vacuum pump is employed to increase the loading time. An automatic grader with an adjusting device for inclined angles and a weighing machine with an automatic alignment device are proposed. In addition, a folding machine is employed to prepare boxes. The specifications for each subsystem are provided. By implementing this system, the freshness of fish can be maintained and the sellers can earn more. This system can also be applied to the cooling system of the fish reservoir of littoral sea fishing boats.

• International Journal of Control, Automation, and Systems
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• v.3 no.4
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• pp.524-532
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• 2005

This paper concerns delay-dependent guaranteed cost control (GCC) problem for a class of linear state-delayed systems with norm-bounded time-varying parametric uncertainties. By incorporating the free weighing matrix approach developed recently, new delay-dependent conditions for the existence of the guaranteed cost controller are presented in terms of matrix inequalities for both nominal state-delayed systems and uncertain state-delayed systems. An algorithm involving convex optimization is proposed to design a controller achieving a suboptimal guaranteed cost such that the system can be stabilized for all admissible uncertainties. Through numerical examples, it is shown that the proposed method can yield less guaranteed cost than the existing delay-dependent methods.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.251-260
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• 2000

Seismic performance evaluation systems require rational classification of structure systems, proper evaluation criteria, and their scoring index for synthesis. Current seismic performance systems need expert judgments based on collection of available data, approximate analysis of important items, and various scoring system. This study presents a three-step seismic performance evaluation system for building structures in Korea. Each evaluation step determines the seismic performance and the method depends on the degree of refinement of analysis. The preliminary step evaluation involves the global attributes of structures such as vertical irregularity, asymmetric plan, redundancy, and age of structures. The second step requires an elastic analysis for estimation of forces acting on critical sections and checks the strength and ductility. The final step requires inelastic capacity of structures. Each stephas own evaluation scheme with proper weighing factor dependent on the importance and consequence. This study applies the fuzzy theory to a scoring method that synthesizes the individual quantity to a representative value.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.3
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• pp.701-706
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• 1994

The discharge coefficients of critical sonic nozzles were obtained in a high pressure gas flow standard system, which was a gravitational weighing system. The discharge coefficients of critical sonic nozzle farbricated according to ISO specifications are in good agreement with ISO correlation. The discharge coefficients for small inlet radius decrease significantly as the inlet length become short due3 to separation at the sharp-edged inlet. For nozzles having long inlet radius, the effects of inlet length on the discharge coefficients were relatively small, but the effects become significant at the short inlet length. The effect of separation at the sharp-edged inlet is stronger than that of the boundary layer growth. The experimental results support that the shape of critical sonic nozzles suggested by ISO specifications is excellent.

• Journal of the Korea institute for structural maintenance and inspection
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• v.2 no.3
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• pp.176-187
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• 1998

The Dismantlement and Construction of the buildings have the characteristic of floating change with repetition within a Time Schedule which has fixed resources, that is, Manpower, Materials and Equipments, and involve many disaster factors in performing each processes. But as these factors are variable, a work supervisor should be able to understand data analysed distinctive factors of each activities systematically, organizationally, and scientifically, and diagrammatic information media so that he can control any complex and situation beyond forecast. Thus this study is intended to be a barometer of weighing if the existing process schedule has taken security into consideration by making the characteristics of organization and action of Work package per process in a building field with more factors like these into a network system and is intended to minimize construction disasters by systematizing this into a Transformational Network.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.821-825
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• 2008

A fuzzy control algorithm is used to weigh alloy metal into electric arc furnace and implemented by using ladder program for programmable logic controller, where weight error and its derivative are used for input variables and vibration amplitude of alloy bin is used for output variable. Proposed fuzzy control algorithm is applied to the plant and results in higher measuring accuracy as well as faster measuring term than conventional on-off control system.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.4
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• pp.356-362
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• 1994

We developed a computer controlled Czochralski puller which automated entire crystal growing processes. Crystal weighing technique was employed for an automatic diameter control. The performance of the system was evaluated by the growth of $LiNbO_3$ single crystals.

• Journal of Periodontal and Implant Science
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• v.44 no.2
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• pp.85-93
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• 2014

Purpose: Low birth weight (LBW) is one of the major public health problems in India. Hence, there is a need to identify risk factors that, when modified, will reduce the burden of unhealthy children on the healthcare system. The objective of this study was to determine whether periodontitis among mothers in the rural population of India is a risk factor for LBW babies. Methods: A hospital-based case control study was conducted among 340 postpartum mothers. The cases consisted of 170 women who had given birth to babies weighing <2,500 g, while the control group consisted of 170 women who had given birth to babies weighing ${\geq}2,500g$. Details of the mothers were taken from the hospital records and through a personal interview, and a full-mouth periodontal examination was performed postpartum, which included probing depth, clinical attachment level, and bleeding on probing on six sites per tooth. Results: LBW cases had a significantly worse periodontal status than the controls, having an odds ratio (OR) of 2.94 (P=0.01). The multivariate logistic regression model demonstrated that periodontal disease is a significant independent risk factor with an adjusted odds ratio (aOR) of 2.85 for the LBW group (95% confidence interval [CI], 1.62-5.5). Other factors showing significant associations with LBW were pre-eclampsia (aOR, 4.49; 95% CI, 1.4-14.7), preterm labor (aOR, 5.5; 95% CI, 3.2-9.9), and vaginal type of delivery (aOR, 2.74; 95% CI, 1.4-5.2). Conclusions: Periodontitis represents a strong, independent, and clinically significant risk factor for LBW. Periodontal therapy should form a part of the antenatal preventive care among rural women in India.