• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.960-972
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• 2014

Marine algal flora and community structure were seasonally investigated at Oryukdo, on the southeast coast of Korea, from March 2011 to February 2014. A Total of 66 seaweed species including 6 green, 7 brown and 53 red algae were identified and 23 species were found throughout the survey period. Seaweed biomass was maximal during summer in 2012 (2276.2 g wet weight $m^{-2}$) and minimal in winter in 2012 (9.1 g wet weight $m^{-2}$). The dominant species in term of biomass were Undaria pinnatifida, Dictyopteris prolifera, Dictyota dichotoma, Sargassum horneri, Rhodymenia intricata, Acrosorium polyneurum, and Polyneura japonica during the suvery period. The flora could be classified into six functional groups: coarsely branched form (30.3%), filamentous form (24.2%), thick leather form (19.7%), sheet form (15.2%), jointed calcareous form (7.6%), and crustose form (3.0%). The numbers of marine algal species in the Oryukdo area were markedly reduced when compared with previous studies at Dongbaekseom in 1971. These results suggest possible future changes in the algal vegetation, considering the physical and chemical pollution loadings in the coastal marine environment of this area.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.3
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• pp.185-191
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• 1999

The fuse used in the high voltage distribution line often fails due to the active ionization caused by the strong electric field at fuse terminal. To suppress the ionization at the high voltage and high capacity current limiting fuse, the particle size and compactness of silica sand, the design, length, notch number and material of element, the diameter and length of fuse body must be considered carefully. However, these are not many proper which is treated with the inherent interrupting characteristics from many parameters at present. Because of these reasons, time and effort are needed to develop the new type fuse by the fuse designers in relation with the inherent characteristics from each of parameters. In this paper we choose 7 parameters with weight value based on study and experimentation and analyzed the characteristics of arcing period. In addition, we proposed the experimental method to experimentation and analyzed the characteristics of arcing period. In addition, we proposed the experimental method to extract the optimal design parameters with minimal effort as related the mutual effect from each of the parameters.

• Journal of Korean Orthopaedic Sports Medicine
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• v.3 no.1
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• pp.36-41
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• 2004

The purpose of this study is to describe the common injuries in soccer players in terms of the orthopaedic operative treatment. We classified foot pain to in forefoot , midfoot, plantar aspect and mentioned the cause, incidence and treatment methods. Ankle pain was classified to anterior, lateral, medial and posterir aspect of the ankle. In all injuries in soccer players, conservative treatment is primary treatment method and we treated operatively in no respond case inspite of the physical therapy and rehabilitation program for sufficient period. The anatomical repair was preferred and minimal invasive surgery was recommended if possible and then focus of treatment is to early return to previous full activities through the rehabilitation program for sufficient period. As a conclusion, it is necessory to understand the mechanism and cause of the common injuries in soccer players and to select the proper treatment method to the degree of the injuries.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.8
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• pp.2170-2187
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• 2023

The general interference is the imperative trouble for simultaneous wireless information and power transfer (SWIPT) system. Although interference has bad influences on the performance of the system, it carries energy simultaneously. In this paper, the energy-constrained relay of the SWIPT system needs to spend much time on energy collecting (EC) in the information transmission (IT) period. Therefore, we propose the scheme of interference signal energy collecting (ISEC) when the interference is strong, and the SWIPT system does not carry out IT. The relay of the system continues to collect energy and stores it until the interference has minimal impact on IT. Then the system performs IT. We divide the collected interference energy equally into several parts, and each IT block receives one part. The proposed scheme is appealing because it can reduce the time of EC in IT period to make the relay spends more time forwarding the received signal in order to improve the performance of the system throughput. Furthermore, we propose a time-switching (TS) protocol based on EC at the relay. And it allows the relay forwarding signal at an appropriate power. Under the protocol, the time of EC can be flexible according to the forwarding power that we give so that the collected energy can be used more efficiently. We give the expressions of the system throughput according to the proposed scheme and protocol. Moreover, the influence of the interference power on the system throughput is also studied.

• Human Ecology Research
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• v.61 no.1
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• pp.141-154
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• 2023

This research was conducted in order to examine previous studies on paternal parenting methods involving adolescent children in terms of their academic field, research period, method and subjects, and family variables. A total of 104 research publications from the period between 2003 and 2022 were investigated, with 99 quantitative research (43 theses and 56 academic journals) and five qualitative data sources. The analysis results show that the topic of fathers with adolescent children was the most studied in the field of education, and it rapidly increased from 2011 to 2014 and then rapidly decreased from 2019. The main subject of the studies was middle-school students, while most of the studies adopted a quantitative approach, with a minimal number of qualitative studies. Parenting studies were concentrated on father variables and several such studies were found to be related to positive resources such as self-esteem and self-efficacy as variables of adolescent children related to fathers' parenting. The results of these studies provide meaningful implications for future research on the fathers of adolescent children and can be used as basic data for developing detailed education and programs.

• Journal of Ocean Engineering and Technology
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• v.37 no.6
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• pp.238-246
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• 2023

This paper proposes an effective inertia coefficient (EIC) in the Morison equation for better wave-force calculations. The OC4 semi-submersible floating offshore wind turbine (FOWT) platform was considered to test the feasibility. Large diffraction at large Keulegan-Carpenter (KC) numbers and the interaction between columns can result in errors in estimating the wave force using the Morison equation with a theoretical inertia coefficient, which can be corrected by the EIC as a function of the wave period and direction. The horizontal and vertical wave forces were calculated using the Morison equation and potential theory at each column, wave period, and wave direction. The EICs of each column were then obtained, resulting in a minimal difference between the Morison inertia force and the wave excitation force by the potential theory. The EICs, wave forces, phase angles, and dynamic motions were compared to confirm the feasibility of an EIC concept under regular and random waves.

• Archives of Reconstructive Microsurgery
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• v.20 no.2
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• pp.96-101
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• 2011

Reconstruction of soft tissue defect of knee joint area has been remained a challenging task for plastic surgeons. The earlier the normal tissue saved and the necrotic tissue removed, the less the patients had complications and functional disability. But such defects are difficult to manage for its poor vascularity, rigid tissue distensibility, easy infectability and a relatively long healing period. The goal of flap coverage in the knee joint should not only be satisfactory wound coverage, but also acceptable appearance and minimal donor site morbidity. We have treated five cases using the anterolateral thigh perforator flaps for reconstruction successfully. In conclusion, we believe that in cases of knee joint area soft tissue defects, flaps like anterolateral thigh perforator flap should be considered as the first line of treatment.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.12
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• pp.1288-1295
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• 1990

In this paper, we propose a parallel processing model for the efficient selection of Prime Implicants of Logic Functions. This model consists of simple parallel processing nodes, connections between them, Max Net (a part of Hamming Net) and quasi essential Prime Implicant selection standard in simplified cost form. Through these, this model selects essential Prime Implicants in a certain period of time regardless of the number of given Prime Implicants and minterms and also selects quasi essential Prime Implicants in short time.

• Food Science and Preservation
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• v.8 no.2
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• pp.164-168
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• 2001

Minimally processed lotus root was stored at 4$^{\circ}C$ followed by dipping in distilled water, 3% ascorbic acid, 1% citric acid, 1% acetic acid, 1% EDTA, 2% lactic acid and 3% malic acid. The weight loss, color, soluble solids, pH, vitamin C and sensory characteristic were measured during storage period. The rate of weight loss decreased in the minimally processed lotus root. ΔL was changed slightly after 1 week storage and 1% acetic acid and 1% EDTA especially retarded a little retardation in browning during storage. Soluble solids was changed slightly, but decreased after 2 week storage in lotus root treated with 2% lactic acid and 3% malic acid. pH increased but vitamin C decreased during storage. The organoleptic quality of lotus root treated 1% EDTA showed the best by sensory evaluation.

• Journal of Korean Society for Quality Management
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• v.35 no.4
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• pp.140-146
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• 2007

In this paper, we consider a periodic imperfect preventive maintenance(PM) policy in which the system's failure rate after each PM remains unchanged. The system undergoes only minimal repairs at failures between PMs. Exact mathematical formula of the expected cost rate per unit time is derived. Optimal number of PMs and optimal maintenance period are derived by minimizing the expected cost rate per unit time. A numerical example is provided to illustrate the proposed approach under Weibull lifetime distribution.