• Journal of Advanced Marine Engineering and Technology
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• 제39권7호
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• pp.709-715
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• 2015

Underwater gliders do not typically have separate propellers for forward motion. They generate propulsive forces based on the difference between their buoyancy and gravity. They can control the volume from the buoyancy engine to adjust the propulsive force. In addition, the attitude of the underwater glider is controlled by a rubberless motion controller. The motion controller can change the mass center and moment of inertia of the inner moving mass. Owing to the change in these parameters, the attitude of the underwater glider is changed. In this study, we derive nonlinear, six degree of freedom (DOF) mathematical models for the motion controller and buoyancy engine. Using these equations, we perform dynamic simulations of the proposed underwater glider, and verify the suitability of the design and dynamic performances of the proposed underwater glider. We then perform the motion control simulation for the pitch and roll angle, and analyze the dynamic performance according to the pitch and roll angles.

• The Journal of Art Theory & Practice
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• 제13호
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• pp.97-132
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• 2012

1799 Francisco de Goya published Los Caprichos with 80 aquatint etchings. On 6 February he advertised it on the front page of the Diario de Madrid. The long advertisement which began with "a collection of prints of capricious subjects, invented and etched by Don Francisco Goya" informed purpose, themes and methods of this collection of prints. According to this advertisement Goya "has chosen as subjects for his work, from the multitude of follies and mistakes common in every civil society and from the vulgar prejudices and lies authorized by custom, ignorance or self-interest, those that he has thought most fit to provide material for ridicules, and at the same time to exercise the artist's imagination." The text emphasized that the 'author' of this series didn't to want to criticise any individual and to be a copyist. From his phantasy Goya invented many creatures like the anthropic, humanized animals etc.. With Los Caprichos he stood on the threshold to Romanticism. The early researchers of Los Caprichos classified its author, Goya as an enlightened intellectual. The similarity of the themes of the series with the subjects of the Enlightenment, his some enlightened 'friends' and the idea to avoid the prevalent mystification of his life supported this theory. But this trend became revised since the 80's of the last century. This made possible to research Goya's works in new perspective and to see that Goya didn't criticise the Spanish society and his contemporaries. Rather he showed its reality and parodied through creatures which are mixtures of the reality that he observed, and visions that he invented. Characters and scenes in Goya's prints are ambiguous and equivocal. They have the values which are defined by the dualistic metaphysic in Europe as oppositional, like good and evil for example, at the same time. Goya himself also appeared in various types in this series. This ambiguousness, or "polyphony", as Jennis Tomlinson defined, is a symptom of the decay of the belief in the Enlightenment which spreaded in Europe as a result of the attack of Bastille and the French Revolution. Goya's self-portrait in pl. 43 of this series, "El sue$\tilde{n}$o de la razon produce monstruos" shows the complex psychology of him and his contemporaries as well. As the rest etchings after this print show witchcraft and monsters reside in the world in which the reason of the Enlightenment and the through the reason weakened God's rule lost their authority. In this thesis I will examine and analyse how Goya represented in Los Caprichos the nature of man and its society, as complex being in which the 'antagonistic' value couple as good and evil couldn't be divided, but are united.

• Journal of the Institute of Convergence Signal Processing
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• 제19권3호
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• pp.139-146
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• 2018

Underwater acoustic communication can be applied to various area such as scientific, commercial and military survey using Autonomous Underwater Vehicles and Unmanned Underwater Vehicles. Underwater communication is studying very actively by advanced country like United States. But differ from wireless communication in the air, underwater acoustic communication has some difficult problems, ISI(Inter Symbol Interference) due to multipath and limit of transmission bandwidth due to slow propagation of sound wave. In this paper, SC-FDE and OFDM transmission system for the cancellation of ISI in conjunction with underwater acoustic channel modeling are applied to the underwater simulation of communication. The performance of these methods in the simulation guide to possibility of adopting in underwater acoustic communication algorithm. For this purpose, we compare SER performance of SC-FDE with that of OFDM for modelled underwater channel. Underwater channel is generated by Bellhop model. Simulation results show above 5dB SNR gain at 10-3 SER. And it demonstrate SC-FDE is efficient method for underwater acoustic communication.

• Journal of Wetlands Research
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• 제6권4호
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• pp.45-57
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• 2004

This study analyzed the effect of land-use enhancement benefits with the flood safety which it is not quantified in the flood damage analysis, Korea. The land-use enhancement benefits mean the enhancement of land-use value according to the rise of flood safety of the protected area by the flood control projects and we performed the analysis of land-use enhancement benefits with the publicly announced land price which can objectively represent the land-use value of a specific area. We verified the statistical significance of the floating rate of land price according to the effects of flood control projects and the characteristics of a river through the analysis of variance. As a result of the verification, the increase of land-use value was represented by the net annual average floating rate of land price. The flood safety was classified as flood damage potential and flood prevention capacity. The flood damage potential was classified according to the rate of urbanization and flood prevention capacity was represented by the conditional annual non-exceedance probability obtained from the frequency analysis with uncertainty for the flood discharge. The study areas were small urban cities and we calculated the conditional annual non-exceedance probabilities of 200-year flood event for the levees constructed with the conditions of 10- and 50-year design frequency. The result was shown that the net annual average floating rate of land price would be raised nearly 5 times for 10%-increase of the conditional annual non-exceedance probability in small city areas.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제28권6호
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• pp.361-374
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• 2016

When the seabed around and under gravity structures such as submerged breakwater is exposed to a large wave action long period, the excess pore pressure is generated significantly due to pore volume change associated with rearrangement soil grains. This effect leads a seabed liquefaction around and under structures as a result from decrease in the effective stress, and the possibility of structure failure is increased eventually. These facts shown above have been investigated in the previous studies related to regular and irregular waves. This study suggested a concrete mat for preventing the seabed liquefaction near the submerged breakwater. The concrete mat was mainly used as a countermeasure for scouring protection in riverbed. According to installation of the concrete mattress, the time and spatial series of the deformation of submerged breakwater, the pore water pressure, and the pore water pressure ratio in the seabed were investigated. Their results were also compared with those of the seabed unprotected with the concrete mat. The results presented were confirmed that the liquefaction potential of seabed under the concrete mattress is significantly reduced under regular wave field.

• Journal of Hospice and Palliative Care
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• 제18권4호
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• pp.285-293
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• 2015

Purpose: This study was conducted to explore the effects of attitude to death in hospice and palliative professionals on their terminal care stress, and to analyze relationships among variables related to the two aforementioned parameters, such as depression and coping strategies. Methods: Participants were 131 hospice and palliative professionals from the cancer units of two tertiary hospitals and two general hospitals, two hospice facilities, two geriatric hospitals, and two convalescent hospitals in J province. Data were collected from April through June 2015 and analyzed using t-test, factor analysis, ANOVA ($Scheff{\acute{e}}$ test), ANCOVA, and Pearson's correlation and a path analysis using the SPSS/WIN 21.0 and AMOS 18.0 programs. Results: The score for attitude to death was low (2.63), and that for depression was 0.45. Among all, 16.0% of the participants showed need for depression management. They scored 3.82 on terminal care stress. The subcategory with the highest mark was inner conflicts on limitation given availability of medical services (4.04). The score on coping strategy was low (3.13). They used passive coping strategies such as interpersonal avoidance (4.03), fulfilling basic needs (3.65) such as sleeping or eating. Attitudes to death had a direct negative effect on the terminal care stress level and indirectly affected through depression and fulfilling basic needs (CS2). Conclusion: It is necessary to provide hospice and palliative professionals with education on death and dying, as well as access to programs that provide emotional support and promote positive cognition of death and dying.

• The Journal of Korean Medicine
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• 제18권1호
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• pp.72-81
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• 1997

The causes of stroke are presumed hypertension, atherosclerosis,. cardiac disease, diabetes mellitus and old age and risk factors of stroke are suggested hypertension, hyperlipidemia. obesity, smoking and drinking etc. Especilly, hypertension is one of the most important cause and risk factor of stroke, therfore without therapy hypertension leads to stroke. The frequence of hypertension is significantly higher in hemorrhage patients of intracranial hemorrhage and subarachnoid hemorrhage. Antihypertensive therapy has an impact not only on the primary prevention of stroke but also on stroke recurrence and the declining of stroke motality has been attributed to the widespread availability and use of antihypertensive therapy. The goals of antihypertensive therapy decrease the complications and motalitv of cardiovascular system and prevent the promoting arteriosclerosis. In this study, we observed the blood pressure change of cb-hemorrhagic patients with hypertension who were hospitalized from 1996. 3. 1 to 1997. 2 .26 in Wonkwang Oriental Hospital. These patients had no antihypertensive therapy and were supplied herb med(Jaum sikpoongtang, Chungrijagamtang, Gojinumja) in medication. Our results suggested as follows. 1. Systolic and diastolic average BP at admission is $150.71{\pm}15.61mmHg$ and $95.00{\pm}8.8mmHg$ and this is hypertension state defining WHO 2. During one week in admission, the blood pressure demostrated a marked declination by SBP 8.97mmHg and DBP 6.22mmHg. 3. During two week in admission, the declination of SBP was significant in paired t-test(p<0.05) but, the declination of DBP was non-significant in paired t-test. 4. The blood pressure during third and fourth weeks gradually declined but, non-significant in test. According to the above results, we suggested that the BP declination Was affected by $Jamyang{\cdot}Jaum$ prescriptions in acute stage of cerebral hemorrhage.

• Korean Journal of Environmental Agriculture
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• 제3권1호
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• pp.16-21
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• 1984

The present study was aimed to investigate persistence of dichlorvos EC, fenitrothion EC, fenthion EC, and phenthoate EC in and on mulberry leaves with special reference to silkworm mortality and cocoon production under greenhouse condition. The halflives of fenitrothion, fenthion, and phenthoate in and on mulberry leaves were ranged from two to three days, while that of dichlorvos was less than 9 hours. The insecticide residues in and on mulberry leaves persisted longer in spring cropping season than in autumn cropping season. Elapsed periods from last application of each insecticide to leaf harvest for silkworm feed and maximum residue limits for safe cocoon production as well as relations between insecticide residues in and on mulberry leaves and silkworm mortality were produced.

• Journal of Wetlands Research
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• 제16권3호
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• pp.327-336
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• 2014

Submerged thin walls are extreme case of submerged rectangular blocks, and could be used for many purposes in rivers or coastal zones, e.g. to tsunami. To understand flow characteristics including flow and pressure fields around a specific submerged thin wall a numerical model was applied which includes computation of hydrodynamic pressure on ${\sigma}$-coordinate. ${\sigma}$-coordinate has strong merits for simulation of subcritical flow over mild-sloped beds. On the other hand ${\sigma}$-coordinate is quite poor to treat sharp structures on the bed. There have been a few trials to incorporate dynamic pressure in ${\sigma}$-coordinate by some researchers. One of the previous approaches includes process of sloving the Poisson equation. However, the above method includes many high-order terms, and requires long cpu for simulation. Another method SOLA was developed by Hirt et al. for computation of dynamic pressure, but it was valid for straight grid system only. Previous SOLA was modified for ${\sigma}$-coordinate for the present purpose and was adopted in a model system, CST3D. Computed flow field shows reasonable behaviour including vorticity is much stronger than the upstream and downstream of the structure. The model was verified to laboratory experiments at a 2DV flume. Time-average flow vectors were measured by using one-dimensional electro-magnetic velocimeter. Computed flow field agrees well with the measured flow field within 10 % error from the speed point of view at 5 profiles. It is thought that the modified SOLA scheme is useful for ${\sigma}$-coordinate system.

• The Journal of the Korea Contents Association
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• 제15권5호
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• pp.200-218
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• 2015

The purpose of the present study was to examine daily lives of elderly welfare recipients and their experiences with social welfare services. Researchers collected and analyzed data through individual interviews with 11 elderly welfare recipients. A major theme in the time context was "Daily lives enduring physical and mental sufferings alone and mismatches of social welfare services": 'Starting same tedious days: trading diligent work for basic living assistance', 'Forced ritual of having meals', 'Struggle with depressing night: not attentive welfare services at closing hours', 'Welfare services suspended in holidays', 'Mind and body withered by economic hardship in winter', 'Social support for enduring weary lives'. In the space context, a major themes was "Inadequate welfare services and social interaction in the context of social isolation": 'Unhygienic and unsafe living environment', 'Hiding places: spending tedious days in vacant lots', 'Community welfare centers useful only for healthy elderly', 'Differences and similarities of elderly in urban and rural areas', 'Receiving restricted medical services at hospitals', 'Hard-to-reach public institutions', 'ambivalence about living as welfare recipients'. Based on the findings, the researchers proposed implications for policy and practice to improve elderly welfare recipients' quality of life.