• Journal of Astronomy and Space Sciences
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• v.35 no.2
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• pp.93-103
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• 2018

Non-specular, vertically upward transit, fast-moving radar echoes are observed in the summer polar upper mesosphere near 90 km using 52 MHz VHF radar at Esrange, Sweden. By resolving maximum echo power movement, the unusual meteor trails propagate vertically upward with taking horizontal displacements at an initial speed of 10 km/s exponentially decreasing with increasing height from 85-89 km, lasting for 3.5 sec. Another upward transit is observed as following a downward transit echo target in about ~1 sec, lasting over 5 sec. The upward motion cannot be explained with the dynamics of penetrating meteors or by atmospheric dynamics. The observation proposes that secondary produced plasma jets occurring from meteor trail are possibly responsible for upward fast moving echoes. The long-lasting (3-5 sec), ascending meteor trails at speeds of a few $10^4m/s$ are distinctive from any previous occurrences of meteors or upper atmospheric electrical discharges in the aspect of long-lasting upward/downward motions. This result possibly suggests a new type of meteor-trail leader discharge occurring in the summer polar upper mesosphere and lower thermosphere.

• Korean Journal of Social Welfare
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• v.61 no.2
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• pp.33-60
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• 2009

This study aimed at examining whether the national rental housing supplied by Korea National Housing Corporation (KNHC) is truly contributing to the upward mobility of housing in low-income households without their own house by comparatively analyzing whether those who moved out of the national rental housing made upward, horizontal or downward housing type mobility. The subjects of this study included 333 people who had moved out of three national rental housing complexes in Cheongju, Chungcheongbuk-do in 2007, which had opened to the first residents two years ago. A telephone survey involving the subjects was carried out. Collected data were analyzed through frequency analysis, cross tabulation analysis and multiple regression analysis, with using the type of residential mobility(downward mobility, horizontal mobility or upward mobility) according to "housing size" and "housing costs" as a dependent variable, and personal and family environment and economic environment as independent variables. According to the results of the analysis, 76.4% of the households made an upward mobility, 1.6% remained little changed, and 22% moved downward in terms of "housing costs," compared to before moving into the national rental housing and while living there. Furthermore, in terms of "housing size" 61.8% of the households moved upward, 16.5% remained little changed and 19.7% moved downward. The variables affecting the upward mobility of housing type included the number of income earners in a household, income earner's occupation and education level. Income earner's amount of income, age and family to support, on the other hand, turned out to have little effect on the upward mobility. Based on the results of the study, the following suggests were made for the supply of effective national rental housing. First, various features of each type of residential mobility should be reflected. Second, national rental housing residents' self-sufficiency should be enhanced to help them move upward in housing type.

• Journal of Sasang Constitutional Medicine
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• v.21 no.1
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• pp.53-62
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• 2009

1. Objectives The purpose of this study is to find the ground why constitution must be classified into 4 types. 2. Methods I analysed the basic presuppositions to class 4 Type Constitution in Sasang Constitutional Medicine(SCM). And I connected the presuppositions with other theories from the viewpoint of directional properties of human body. 3. Results and Conclusions The most important presupposition to class 4 Type Constitution and apply to clinical therapy in SCM is that there is native strength and weakness of lung's Exhale Dispersing Qi, liver's Inhale Gathering Qi, spleen's Ascending Yin Qi and kidney's Descending Yang Qi. If there is superior tendency of Qi flow direction in human body, 6 directions(upward, downward, forward, backward, outward and inward) will be remarkable. But, in embryonic period, the outer skin is originated from the back(ectoderm) and the alimentary canal is from the front(endoderm). Therefore 4 directions(upward, downward, outward and inward) will be more remarkable, and those directions are included in the former presupposition.

• Journal of the Korean housing association
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• v.20 no.5
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• pp.9-21
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• 2009

This study classified visual perception types of access space at 17 five-star hotels in Jejudo and examined their cognitive characteristics and image formation structures in an effort to provide basic information important for designing the elevation and the access spaces of a hotel. The results of this study are as follows. Access space image of experimental hotels showed more negative evaluations at both city hotels and resort hotels, viewing angle (upward angle) was also positively evaluated between $10^{\circ}{\sim}12^{\circ}$ and $18^{\circ}$ and central type in arrangement type and detour access and straight access types in access circulation type were positively evaluated. When viewed from an upward angle of $10^{\circ}$ to $12^{\circ}$, the most important factors were as plasticity, decorativeness, and creativity; from $18^{\circ}$ it was such factors as harmony and peculiarity; and at $45^{\circ}$ it was factors like decorativeness and stability. In considering the various access types, the most important factors in a straight access type were peculiarity and harmony; for one-time curved access type it was by decorativeness, creativity, Peculiarity, and stability; and for detour access types it was decorativeness, stability, and peculiarity. Influential of factors affecting image formation and plasticity and harmony factors and the form had more influences on image formation.

• Korean Journal of Heritage: History & Science
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• v.51 no.4
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• pp.24-43
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• 2018

Thirty-five of Hwaban of Jeongjagak had been built in the last three hundred years, which means a Hwaban was made in almost every ten years. Jeongjagak is a building that requires a certain ornamentation having the identical Gongpo type, called E-ikgong, and maintains the same shape for a long time. While Hwaban is an element that faithfully serves the ornamental role, the field study found that Hwaban-chogak went through various changes over the years unlikely to Jeongjagak. This study enumerates and classifies the various types of Hwaban-chgak by outlining the similarities/differences of the various types of Hwavanchogak, and by discovering what the craftsmen aimed to express through the Hwaban-chogaks. As a result, Hwaban-chogak can be generally divided into two categories depending on the starting point of Chogak: 'Downward-Type' and 'Upward-type' and the study tried to find the origin of that. The first represents the stems of Hwaban crafts flowing from top to bottom, and the latter showing the opposite direction. Around 1740s Upward-type can be chronologically caragorised as; 'original- type' which contains lotus and 'modified- type' which eliminates lotus. It is inferred that the modified-type was caused by the employment system of the craftsmen. It is also recognized that the main frame of Hwaban-chogak had been maintained despite the fact that Chogak became increasingly ornamental for the next a hundred years from the Hwaban-chogak drawings in Whaseong-seongyeog-uigwe, which was completed in 1796. The study has a limitation that the focus of the research is only on the Hwaban of Jeongjagak and expected to look into Hwaban in the context of other construction elements such as Ikgong, Daegong and Anchogong for further studies.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.953-967
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• 2017

In this paper, a complete station blackout (SBO) or complete loss of electrical power supplies is simulated and analyzed in a downward cooling 5-MW pool-type Material Testing Reactor (MTR). The scenario is traced in the absence of active cooling systems and operators. The code nodalization is successfully benchmarked against experimental data of the reactor's operating parameters. The passive heat removal system includes downward water cooling after pump breakdown by the force of gravity (where the coolant streams down to the unfilled portion of the holdup tank), safety flapper opening, flow reversal from a downward to an upward cooling direction, and then the upward free convection heat removal throughout the flapper safety valve, lower plenum, and fuel assemblies. Both short-term and long-term natural core cooling conditions are simulated and investigated using the RELAP5 code. Short-term analyses focus on the safety flapper valve operation and flow reversal mode. Long-term analyses include simulation of both complete SBO and long-term operation of the free convection mode. Results are promising for pool-type MTRs because this allows operators to investigate RELAP code abilities for MTR thermal-hydraulic simulations without any oscillation; moreover, the Tehran Research Reactor is conservatively safe against the complete SBO and long-term free convection operation.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.6
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• pp.911-918
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• 2006

This study was conducted to evaluate the effect of the launder type on settling performance and hydrodynamic behavior within the two certain full-scale sedimentation basins (each flow rate/one basin; $10,000m^3/d$); one is the transverse typed launder(existing basin) and the other is building the finger type launder in combination with the longitudinal baffle. Comparative experimental investigations have been carried out through residual turbidity and particle concentration measurements in each effluent from two basins with the transverse and the finger type launders, respectively. From the experimental results, we could observe that turbidity removal rate in the finger type launder basin (modified basin) is about 30% higher than that in the transverse type launder basin (existing basin). Also, from the measurement of total particle concentration in each effluent, the removal efficiency was improved about 27% within modified basin compared to the existing basin. In order to explain the comparative experimental results and investigate the hydridynamic behavior within each basin in more detail, we conducted computational fluid dynamics (CFD) simulation and verified simulation results with acoustic Doppler velocimetry (ADV) technique. From the CFD simulation, it was investigated that extreme upward flow occurs underneath of the transverse launder. On the other hand, in the case of modified basin, the upward flow, which occurred in the beneath of launder, was much less than that in the existing basins.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.6
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• pp.111-121
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• 2015

The objective of this study is to develop an automatic object changer unit to improve changing process problems existing in the conventional horizontal machining center. In order to perform this objective, an upward and downward traverse unit was designed. This unit consists of a motor, reducer, chain and sprocket wheel, and an upper and lower base. This automatic object changer unit performs a sliding contact motion in a purpose built and designed frame. Constraint conditions for the upward and downward traverse unit were first designed. Then, an operation mechanism was designed and introduced as the sum of the kinetic energy for the sprocket wheel and the upper and lower base and which was based on the moment of inertia, which is the kinetic energy of the converted upward and downward traverse unit in the side of the reducer. The paper covers the design of th e Automatic Pallet Changer for th e machining center.

• Solar Energy
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• v.18 no.3
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• pp.95-105
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• 1998

In this study, basic design data which were required for development of highly efficient ice storage system with low temperature latent heat were experimentally obtained. The ice storage system considered in this study was the one that has been widly used in the developed country and called the ice-on-coil type. Using the system, the ice storage performance for various design parameters which were the flow direction and the inlet temperature of the secondary fluid was tested. In addition, the timewise variation of the interface profiles between the solid and the liquid were visualized, and the heat transfer characteristics of the Phase Change Material(PCM) in the ice storage tank were Investigated. During the freezing processes in the ice storage tank with several vertical tubes, decrease of the heat transfer area and the heat resistance of the ice layer made the increasing rate of ice packing factor(IPF) less. The total freezing energy for the upward flow of the secondary fluid was higher than that for the downward flow. The average ice storage efficiency for the upward flow of the secondary fluid was higher than that for the downward flow.

• Journal of Korea Water Resources Association
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• v.34 no.4
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• pp.381-390
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• 2001

This is to evaluate the ascending capacity of migratory fish in the pool and weir type fishways. Ascending environment of the migratory fish in rivers is analyzed through eco-hydraulic experiments using sweetfish, Plecoglossus altivelis, trout, Oncorhnchus mykiss, and surveying the fall height of existing pool and weir type fishways. When the fall height is less than 16.0cm, the ascending capacity of sweetfish in the pool and weir type fishways is greater than trout. On the other hand when the fall height is over 20.0 cm, the ascending capacity of trout is greater than sweetfish. A sweetfish may prefer to jump for upward moving than trout. And its endurance after upward jumping over wear is greater than that of sweetfish. Because of high fall height of existing pool and weir type fishways the migratory environment in rivers is so poor. When the pool and weir type fishways are designed and constructed in river the fall height of weir must be considered for the variety of migratory fish living in river and the fall height of weir less than 20.0cm is suggested.