• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.3
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• pp.175-187
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• 2013

Fuel consumption in fisheries is a primary concern due to environmental effects and costs to fishermen. Much research has been carried out to reduce the fuel consumption related to fishing operations. The fuel consumption of fishing gear during fishing operation is generally related to hydrodynamic resistance on the gear. This research demonstrates a new approach using numerical methods to reduce fuel consumption. The results from the simulation were verified with results that mirrored the model experiments. By designing the fishing gear using drawing software, the whole and partial resistance force on the gear can be calculated as a result of simulations. The simulation results will suggest suitable materials or gear structure for reducing the hydrodynamic forces on the gear while maintaining the performance of the gear. Furthermore, the efficiency of low energy used anchovy dragnet as economic point of view will be dealt. This research will helpful to reduce the GHG emissions from fishing operations and lead to reduce fishing costs due to fuel savings.

• Atmosphere
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• v.16 no.2
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• pp.67-83
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• 2006

The statistical analysis for the springtime windstorm in Korea shows that Yeongdong region has the highest occurrence frequency during recent 10 years. The objective of this study is to find possible mechanisms for the downslope windstorm formation in the Yeongdong region by using a mesoscale numerical model, WRF. Dynamical process, wave breaking (hereafter WB), is qualitatively investigated as the candidate mechanism for a windstorm event occurred in 5 April, 2005. WB is developed in upper troposphere downstream, since stable air is lifted by the Taebaek mountain. This process can cause and maintain the severe downslope windstorm by drawing the upper flow down to the surface. And the intensified downslope wind leads the hydraulic jump (hereafter HJ) in downstream region. Froude numbers at Chuncheon (upslope side), Seorak Mountain (crest), Yangyang (lee side), and the East Sea (distant downstream position) are estimated by about 0.4, 1.0, 1.6, and 0.6, respectively. This result implies that the accelerated and supercritical (Fr>1) flow adjusts to the ambient subcritical (Fr<1) conditions in the turbulent HJ. In addition, we find the formation of upstream inversion near top level of the mountain cause the intensification of HJ. Experiments to examine the orographic effect on the mechanisms suggest that the magnitudes of WB and HJ are larger in the experiment of higher topography, but there is no significant difference of windstorm magnitude among the experiments. Another important result from these sensitivity experiments is that the intensity of downslope windstorm strongly depends on the magnitude of upper (2~4 km) wind in upstream side.

• Journal of Arbitration Studies
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• v.25 no.2
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• pp.3-17
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• 2015

For many years commentators have requested more active regulation of attorney ethics in international arbitration. Gradual deterioration of ethical standards in international arbitration will bring disrepute and, once its reputation is lost, it could take decades to rebuild confidence. The first reason for increasing unethical behavior is that there is no ethical code generally applied to all lawyers participating in international arbitration. A second reason might be that nobody is actively regulating attorneys in international arbitration. The first step to solve this problem is that major arbitration institutions should cooperate to enact a uniform code of conduct to be generally applied to all attorneys representing parties in international arbitration. Recently, IBA and LCIA prepared guidelines on party representation in international arbitration, and the guidelines will help attorneys follow uniform standardsof ethics. However, this will not be sufficient. There should be a regulating body to monitor attorney ethics and take sanctions against unethical attorneys accordingly. Arbitrators, who can see unethical behavior by attorneys from the closest distance, are the most appropriate regulating force rather than courts of arbitration seat or an attorney's licensing country. Of course, arbitrators don't have powers to withdraw or suspend an attorney's license, but they have powers to control attorneys'behavior within arbitration proceedings such as an allocation of fees and costs, barring the assertion of claims or defenses, drawing adverse inferences, or precluding the submission of evidence or testimony. Furthermore, arbitrators should be provided with such obligation as active control of attorney ethics. Even arbitration institutions should participate by imposing on an attorney who is a repeat offender a suspension from appearing in future arbitrations. Unethical behavior will decrease through concerted actions among arbitrational institutions to introduce a uniform code of conduct and to empower arbitrators for more efficient regulation of attorney ethics.

• Nuclear Engineering and Technology
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• v.53 no.9
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• pp.3085-3099
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• 2021

Investigations of large commercial aircraft impact effect on nuclear power plant (NPP) buildings have been drawing extensive attentions, particularly after the 9/11 event, and this paper aims to numerically assess the damage and vibrations of NPP buildings subjected to aircrafts crash. In Part I of present paper, two shots of reduce-scaled model test of aircraft impact on NPP were conducted based on the large rocket sled loading test platform. In the present part, the numerical simulations of both scaled and prototype aircraft impact on NPP buildings are further performed by adopting the commercial program LS-DYNA. Firstly, the refined finite element (FE) models of both scaled aircraft and NPP models in Part I are established, and the model impact test is numerically simulated. The validities of the adopted numerical algorithm, constitutive model and the corresponding parameters are verified based on the experimental NPP model damages and accelerations. Then, the refined simulations of prototype A380 aircraft impact on a hypothetical NPP building are further carried out. It indicates that the NPP building can totally withstand the impact of A380 at a velocity of 150 m/s, while the accompanied intensive vibrations may still lead to different levels of damage on the nuclear related equipment. Referring to the guideline NEI07-13, a maximum acceleration contour is plotted and the shock damage propagation distances under aircraft impact are assessed, which indicates that the nuclear equipment located within 11.5 m from the impact point may endure malfunction. Finally, by respectively considering the rigid and deformable impacts mainly induced by aircraft engine and fuselage, an improved Riera function is proposed to predict the impact force of aircraft A380.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.2
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• pp.97-104
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• 2021

Together with the emerging of the Eco-ship, the application of large-diameter and high-efficiency propeller required more careful attention than before in the design of the shafting system. After the adoption of Environmentally Acceptable Lubricants (EAL) to the stern tube lubrication oil, a number of aft stern tube bearing accidents have been reported, and a variety of institutions have actively conducted research on the cause relationship. This study attempted to find the cause of the accident by measuring the alignment of the shafting system of a medium-sized product/chemical tanker with aft stern tube bearing damage and analyzing the reaction force of each bearing. In addition, a reasonable solution to the correction of the shaft alignment was suggested and the feasibility was reviewed. Through various measured data and analysis, the actual installation of shafting system was slightly different from the design drawing condition, but it was found that each bearing load distribution was within the allowable range. Therefore, it was confirmed that the cause of this accident was due to the dissatisfaction the misalignment slope of aft stern tube bearing rather than the effect of the bearing overload. As a solution to this cause, countermeasures such as double slope were suggested in the aft stern tube bearing, and the characteristics of EAL also seem to have an indirect effect.

• Journal of Korea Water Resources Association
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• v.52 no.1
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• pp.1-10
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• 2019

This study investigates the flow characteristics, such as velocity distributions, size and location of recirculation zone, longitudinal flow change rates, and bifurcation discharge ratio in the bifurcation channel by TELEMAC-2D, a 2D numerical model. The numerical model is validated by previous experimental results and the numerical results are in relatively good agreement with the experimental results, such as the water surface elevation and velocity distribution in the channels. As the inertial force and moment in the main channel decrease, the bifurcation discharge ratio increases, and the relative high velocity distribution becomes wider and the reverse velocity of the main stream decreases in the branch channel. As the bifurcation discharge ratio increases, the size of the recirculation zone in the branch channel decreases and it can be more clearly calculated by determining the point where the longitudinal froude number $Fr{\approx}0$ as well as drawing the distribution of the streamline distribution.

• International journal of advanced smart convergence
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• v.12 no.2
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• pp.76-83
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• 2023

Squatting of agricultural work can cause musculoskeletal disorders due to excessive pressure and rotational force on the knee joint In order to improve the assistive chair used in squatting agricultural work so that it can be used in a narrow groove, it is intended to improve the musculoskeletal harm of squatting work by attaching a spring on the assistive chair. Therefore, in the presenty study, 3D drawing was done using ProEngineer (3D), and a mock-up was produced and tested. Using pro-Engineer, it was judged that it was rare for plastic to be broken by a spring, so the analysis was conducted with a focus on springs. It was found that the structure that can absorb the shock according to the rigidity of the tape spring and balance the body is that the power to withstand the load of the weight is distributed as a whole when five springs are used. Electromyography was measured using ME600 (Mega Electronics, Finland) Measuring equipment attached to the waist, thighs, calves, and shins. EMG values were measured and compared with the prototype in two ways, when the worker did not wear the product and when he wore an existing product on the market. As a result of the experiment when using the prototype, the maximum EMG value for each part is considered to be helpful in preventing musculoskeletal diseases as the amount of muscle used is reduced in the waist, thighs, calves, and shins.

• Journal of the Daesoon Academy of Sciences
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• v.21
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• pp.255-284
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• 2013

There are many discourses about 'religion and women,' but it is no exaggeration to say that there is none about 'religion and men.' This is because the existing religions have been male-centric and have produced legions of male-dominated cultures. In Catholic Church, even today, only men can become the Pope, and women are not allowed to enter priesthood. Meanwhile, in the Islamic cultural areas, the reality is that women are being victimized by men who do not recognize the bad habits such as honor killings, or honor crimes. It is certain that gender discrimination in religious and cultural areas cannot be overlooked. This study focuses on the understanding of women in the thought of Daesoonjinrihoe(大巡眞理會), that is, the Daesoon Thought, which claims to advocate world peace. Daesoonjinrihoe is understood as a thought which tries to overcome gender discrimination prevalent in the existing religions and presents the vision of a new religion which aims to realize a new world of peace by drawing a distinction between the Former Heaven and the Latter Heaven. This study examines the understanding of women by looking at the tenet of Daesoonjinrihoe that consists of 'YeumYangHapDeok(陰陽合德), SinInJoHwa(神人調化), HaeWon-SangSaeng(解冤相生), DoTongJinGyeong(道通眞境).' The tenet is thought of as the basis of creed on which the understanding of women by the Daesoon Thought can be grasped as it basically contains the essence of teaching of the order. In the Daesoon Thought, women have the same status as men; women can become holy and dignified beings by engaging in independent, active, and autonomous spiritual exercises, and serve as a driving force for the realization of the ideal world. This understanding of women by the Daesoon Thought contains the idea of peace which can turn 'the culture of discrimination' into 'the culture of equality,' and 'the culture of life destruction' into 'the culture of life care.'

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.4
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• pp.99-106
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• 2024

The problem of the bridges(Hasjiwokakero, Hasi) puzzle, which connects the bridge(edge) required by the island(vertex) without crossing the horizontal and vertical straight bridges except for the diagonal to form a connected network, is a barren ground for research without any related research. For this problem, there is no algorithm that presents a generalized exponential time brute-force or branch-and-bound method. This paper obtained the initial solution of the lattice graph by drawing a grid without diagonal lines for a given BP, removing unnecessary edges, and supplementing essential bridges. Next, through insufficient island pair path matching, the method of adding insufficient edges to the route and deleting the crossed surplus edges(bridges) was adopted. Applying the proposed algorithm to 24 benchmarking experimental data showed that accurate solutions can be obtained for all problems.

• Journal of the Korean Magnetics Society
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• v.22 no.2
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• pp.58-65
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• 2012

Since Nd-Fe-B magnet was first synthesized in 1983, many new applications have emerged in the past two decades. With regard to motor market, it will expand because of strong energy saving requirements from the automobile and electric application markets. Especially, permanent magnet motors for hybrid and electric vehicles are drawing great attention and the usage of Nd-Fe-B magnets will increase all the more hereafter. There is, however, a serious problem as motors in such eco-friendly cars are said to operate in high temperatures of about $200^{\circ}C$. Nd-Fe-B magnet has a drawback of dramatically decreasing coercive force with the rise of temperature. In order to improve this aspect. the best way is to add dysprosium (Dy) into the magnet. So, Dy has become an essential element for Nd-Fe-B high-performance magnet as it helps to maintain coercive force even at high temperatures. On the other hand, the rare earth resources in the earth crust are eccentrically-located and its majority is produced in China. There is a need to reduce its usage as, especially compared to light rare earth elements as neodymium (Nd) and samarium (Sm), heavy rare earth elements including Dy are unevenly distributed to a dramatic degree, their output low, and their prices are about 10 times that of Nd. The present article includes a summary of the trend in research and development of motors and permanent magnets to solve rare-earth resources problem.