• Journal of Animal Environmental Science
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• v.1 no.1
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• pp.83-102
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• 1995

Composting is an ecologically sound method of recycling organic waste. Its advantages include the maintenance of soil fertility and improvement of soil physicochemical property. It is an essential part of the waste minimization. That is, composting should be included to increase the recycling rate up to more than 20%. To encourage composting of waste, it is necessary to develop some effective composters of small scale facilities and densely populated areas. For medium and large-size facilities, the optimum process should be selected. Technical counselling and support is desirable for small scale composters for urban residential and rural area. On the other hand, adequate amendment of relevant legislation should be followed to encourage composting. An example of unreasonable legislation is the current fertilizer management act. According to the regulation, the maximum allowable limit of lead in the compost is less than 150ppm, which is too strict. This limit should be increased to at least 300ppm, which is the observed level in most states in USA. At the same time, sound infrastructure should be established and decent publicity work should be achieved to accelerate composting activity. In this paper the desirable standard for some heavy metal concentration in the compost were suggested.

• Asian review of World Histories
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• v.1 no.1
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• pp.45-84
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• 2013

Empirical research into Đại Việt before the $14^{th}$ century has made little progress since the 1990s. To improve this situation, I here examine how the L$\acute{y}$ dynasty (1009-1226), the first long-lasting dynasty of Đại Việt, established stable local ruleafter the "Tang-Song Transition" in China that changed the entire picture of East Asia (including both Southeast and Northeast Asia). This paper focuses on two issues. First are the local administrative units and their governors. The nature of both higher units like lộ(circuits), phủ and ch$\hat{a}$u (provinces), and basic units like hươg and gi$\acute{a}$p (districts?) will be examined. Second, I examine non-institutional channels of local rule by the imperial family. By combining such administrative and non-administrative means, the L$\acute{y}$ central court enforced a considerably stable local rule for two centuries. Finally, I attempt some preliminary comparisons with the local rule of Goryeo (918-1392) in the Korean peninsula, a polity that shared many features with Đại Việt in the process of localization of the Tang and Song models. I hope this approach of viewing small empires from the standpoint not of their "goal" (modern states) but of their "start" (charter polities), will enrich the discussion of East Asian small empires.

• Genomics & Informatics
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• v.9 no.2
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• pp.74-78
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• 2011

Numerous restraints and simplifications have been developed for methods that anticipate protein structure to reduce the colossal magnitude of possible conformational states. In this study, we investigated if globularity is a general characteristic of proteins and whether they can be applied as a valid constraint in protein structure simulations with approximated measurements (Gb-index). Unexpectedly, most of the proteins showed strong structural globularity (i.e., mode of approximately 76% similarity to the perfect globe) with only a few percent of proteins being outliers. Small proteins tended to be significantly non-globular ($R^2$=0.79) and the minimum Gb-index showed a logarithmic increase with the increase in protein size ($R^2$=0.62), strongly implying that the non-globular characteristics might be more acceptable for smaller proteins than larger ones. The strong perfect globe-like character and the relationship between small size and the loss of globular structure of a protein may imply that living organisms have mechanisms to aid folding into the globular structure to reduce irreversible aggregation. This also implies the possible mechanisms of diseases caused by protein aggregation, including some forms of trinucleotide repeat expansion-mediated diseases.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.5
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• pp.520-526
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• 2013

As the increasing of capacity and technology of power facilities, rotating machines are getting higher at capacity and voltage scale. Thus the monitoring and diagnosis of generators for fault detection has attracted intensive interest. In this paper, we developed fault diagnosis system for monitoring the fault operations in bad power systems. In order to verify the performance of this fault diagnosis system, we made the small scaled testing system which has the same winding structure of the real synchronous generator. The magnetic flux patterns in air-gap of a small-scale generator under various fault states as well as a normal state are tested by hall sensors and the fault detection system.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.327-334
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• 2004

Spectroscopic and electrostatic probe measurements were made to examine plasma characteristics with or without a metal plate for a 10-㎾-class direct-current arcjet Heat fluxes into the plate from the plasma were also evaluated with a Nickel slug and thermocouple arrangement. Ammonia and mixtures of nitrogen and hydrogen were used. The NH$_3$ and $N_2$+3H$_2$ plasmas in the nozzle and in the downstream plume without a plate were in thermodynamical nonequilibrium states. As a result, the H-atom electronic excitation temperature and the $N_2$ molecule-rotational excitation temperature intensively decreased downstream in the nozzle although the NH molecule-rotational excitation temperature did not show an axial decrease. Each temperature was kept in a small range in the plume without a plate except for the NH rotational temperature for NH$_3$ gas. On the other hand, as approaching the plate, the thermodynamical nonequilibrium plasma came to be a temperature-equilibrium one because the plasma flow tended to stagnate in front of the plate. The electron temperature had a small radial variation near the plate. Both the electron number density and the heat flux decreased radially outward, and an increase in H$_2$ mole fraction raised them at a constant radial position. In cases with NH$_3$ and $N_2$+3H$_2$ a large number of NH radical with a radially wide distribution was considered to cause a large amount of energy loss, i.e., frozen flow loss, for arcjet thrusters.

• Macromolecular Research
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• v.10 no.6
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• pp.325-331
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• 2002

Phase behavior of a PEO-PPO-PEO (Pluronic P103) triblock copolymer in water is investigated using small-angle neutron scattering (SANS), small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and rheology. Pluronic P103 shows apparent two gel states in different temperature regions. The first sol-to-gel transition at a lower temperature (i.e., the hard gel I state) turns out to be the hexagonal microphase as evidenced by the combined SANS and SAXS and the frequency dependence of both G′ and G" in rheology. In contrast to the hard gel I, the second sol-to-gel transition (i. e., the hard gel II state) at a higher temperature represents the block copolymer micelles in somewhat disordered state rather than the ordered state seen in the hard gel I. Moreover, turbidity change depending only on the temperature with four distinct regions is observed and the large aggregates with size larger than 5,000 nm are detected with DLS in the turbid solution region. Based upon the present study, two different gelation mechanisms for aqueous PEO-PPO-PEO triblock copolymer solutions are proposed.

• Bulletin of the Korean Chemical Society
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• v.20 no.1
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• pp.35-41
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• 1999

Stability characteristics of hyperbolic reaction-diffusion equations with a reversible Brusselator model are investigated as an extension of the previous work. Intensive stability analysis is performed for three important parameters, Nrd, β and Dx, where Nrd is the reaction-diffusion number which is a measure of hyperbolicity, β is a measure of reversibility of autocatalytic reaction and Dx is a diffusion coefficient of intermediate X. Especially, the dependence on Nrd of stability exhibits some interesting features, such as hyperbolicity in the small Nrd region and parabolicity in the large Nrd region. The hyperbolic reaction-diffusion equations are solved numerically by a spectral method which is modified and adjusted to hyperbolic partial differential equations. The numerical method gives good accuracy and efficiency even in a stiff region in the case of small Nrd, and it can be extended to a two-dimensional system. Four types of solution, spatially homogeneous, spatially oscillatory, spatio-temporally oscillatory and chaotic can be obtained. Entropy productions for reaction are also calculated to get some crucial information related to the bifurcation of the system. At the bifurcation point, entropy production changes discontinuously and it shows that different structures of the system have different modes in the dissipative process required to maintain the structure of the system. But it appears that magnitude of entropy production in each structure give no important information related for states of system itself.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.72.3-72.3
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• 2019

The observation of transient objects such as supernovae or variable stars requires a survey of the wide sky and quickly extracting the results. In accordance with this purpose, we have been developing an automatic observing software, KAOS (Kyung Hee University Automatic Observing Software) as a series. KAOS30 was the first series of KAOS and it was applied to the 30-inch platform at the McDonald Observatory in the United States of America. KAOS76 controls the 76-cm telescope at Kyung Hee Astronomical Observatory. In this poster, we introduce KAOS10 for controlling a portable telescope with a small aperture size attaching a guiding camera as QHY-5L II. Kyung Hee University auto-guiding package which includes the auto-guiding function for small aperture size telescope was also developed. Additionally, the Telescope Control Package(TCP) can communicate with the main server to do astrometry for pointing and identifying targets efficiently. KAOS10 has a universal interface that will be useful for the research of both amateurs and professionals.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.6_2
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• pp.1081-1091
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• 2020

The most recent issue of offshore plants that produce oil and gas are the decommissioning engineering of aged or discontinued platforms. There are many platforms that are being dismantled in the United States, Europe, and areas in Southeast Asia. In particular, more than 400 old platforms in Southeast Asia (Indonesia, Malaysia) are preparing to dismantle. They are spread out across Southeast Asia with a water level of 50 meters and small-scale of less than 10,000 tons. However, this offshore plant decommissioning market is a very suitable market for small and medium-sized shipyards in Korea to enter with their established equipment and engineers. Platform decommissioning is conducted according to decommissioning procedures. However, there are some difficulties in market advances as no developed case studies or process models are established on how platform structures and components are to be dismantled and how the dismantled material is to be reused and recycled. Therefore, this study presented domestic and foreign regulations on the reuse and recycling of oil and gas producing offshore plant platforms, case analyses on developed decommissioning engineering, platform reuse and recycling guidelines, and platform and pipeline decommissioning processes and methods.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2635-2649
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• 2022

CEFR is a small core-size sodium-cooled fast reactor (SFR) using high enrichment fuel with stainless-steel reflectors, which brings a significant challenge to the deterministic methodologies due to the strong spectral effect. The neutronic simulation of the start-up experiments conducted at the CEFR have been performed with a deterministic code system RAST-F, which is based on the two-step approach that couples a multi-group cross-section generation Monte-Carlo (MC) code and a multi-group nodal diffusion solver. The RAST-F results were compared against the measurement data. Moreover, the characteristic of neutron spectrum in the fuel rings, and adjacent reflectors was evaluated using different models for generation of accurate nuclear libraries. The numerical solution of RAST-F system was verified against the full core MC solution MCS at all control rods fully inserted and withdrawn states. A good agreement between RAST-F and MCS solutions was observed with less than 120 pcm discrepancies and 1.2% root-mean-square error in terms of k_eff and power distribution, respectively. Meanwhile, the RAST-F result agreed well with the experimental values within two-sigma of experimental uncertainty. The good agreement of these results indicating that RAST-F can be used to neutronic steady-state simulations for small core-size SFR, which was challenged to deterministic code system.