• Journal of Environmental Policy
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• v.5 no.1
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• pp.71-97
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• 2006

This paper explores the history of environmental movements and policymaking in the city of Austin, TX and addresses the most recent element of the city's environmental policy, the Smart Growth Initiative. Austin's intense growth over the last 35 years has increased a growing awareness of environmental impacts by humans. The Austin municipal government has tried to adopt environmental measures and various policy initiatives ranging from comprehensive plans to its latest Smart Growth Initiative. The long history of comprehensive planning and watershed protection ordinances indicate that while environmental issues have continually presented as priority issues, it has failed to integrate as a part of the municipal government. This shows that the efforts of political actors have not been sufficient to sustain progressive environmental regimes with environmental issues despite the initial motivation of the state.

• Journal of the Korean Vacuum Society
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• v.14 no.2
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• pp.84-90
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• 2005

The influence of plasma parameters on the growth of $In_{0.2}Ga_{0.8}N/GaN$ heterostructures has been investigated using plasma-assisted molecular beam epitaxy. Since plasma ejects plenty of energetic particles with different energy levels and flux density at various rf power levels, plasma modulated both growth rate and optical properties significantly. For instance, surface roughness and the emission spectrum of photoluminescence were degraded at low and high rf power. According to sharp interfaces between epitaxial films and strong peaks observed from photoluminescence spectra, our experimental setup presented optimal operation range of rf powers at around 400W. The phenomena could be explained by the presence of energetic particles modulating the rate of plasma stimulated desorption and surface diffusion, and energetic particles exceeding critical value resulted in the incorporation of defects at subsurface. The optimal rf power regime increased by 100W for $In_{0.2}Ga_{0.8}N/GaN$ growth in comparison with GaN. The effects of rf power were discussed in conjunction with kinetic processes being stimulated by energetic particles.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.25-30
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• 2004

Rice seedlings were used to examine the effect of UV-B radiation on leaf elongation and development. Leaf elongation in both rice seedlings showed differently depending on each leaf age. UV-B radiation strongly reduced leaf elongation, 58-66% compared to without UV-B radiation, of two rice seedlings, therefore, those seedlings could not grow further. Both control and plants grown under UV-B regime showed a diurnial fluctuation in growth rate, showing maximum growth during the light period and minimum during the dark period. Leaf growth at the third leaf stage by UV-B treatment was considerably reduced by 1.7-fold than the control whereas at the fifth leaf stage was not changed. Hydrogen peroxide was considerably increased in the second phase of UV-B-induced response as catalase and peroxidase are deactivated with an increase of UV-B radiation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.5
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• pp.397-401
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• 2003

This experiment was conducted to know the characteristics of kernel growth as affected by various temperature regimes during grain filling using the varieties Hwaseongbyeo, Ilpumbyeo and Chucheongbyeo. The rice plants tested were grown in the natural condition at 1/5000a Wagner pots until flowering. After flowering, the rice plants were moved to controlled temperature conditions in a phytotron. The minimum/maximum daily temperature in the phytotron was controlled by 12/18, 15/21, 18/24, 21/27, and 24/$30^{\circ}C$, respectively. The grain weights were measured every three days after treatment. The mean daily kernel growth rate during active grain filling period showed different responses among varieties under various temperature regimes. The kernel growth rate of Chucheongbyeo was seriously reduced as temperature regimes were decreased. However, that of Ilpumbyeo was not influenced so critically. Ilpumbyeo showed some advantages in grain filling under low temperature regimes compared to Chucheongbyeo. The lag phase in grain filling of Chucheongbyeo was the longest among tested varieties, followed by Hwaseongbyeo under daily mean temperature regime of $15^{\circ}C$. Kernel weight of Ilpumbyeo increased fast in early grain filling phase under low temperature. This characteristic may be favorable for grain filling in temperate zone where the daily mean temperature is drastically dropped during grain filling period. Regression analysis with kernel growth rate and temperature showed the estimated critical low temperature for grain filling among varieties were $9^{\circ}C$, $12^{\circ}C$, $13^{\circ}C$ in Ilpumbyeo, Hwaseongbyeo and Chucheongbyeo, respectively. Under moderate temperature the duration of grain filling of Ilpumbyeo was longer than that of Chucheongbyeo. However, Under low temperature that of Ilpumbyeo was more favorable than Chucheongbyeo.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.725-733
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• 2001

In this study, the relationship between growth factors for Pinus densiflora stands in Anmyun-Island was analyzed and dynamic growth model was prepared. A total of 96 sample plots was investigated in which dbh and height of individual trees were measured. From these plot data, quadratic mean dbh, mean height, dominant tree height, stem number per ha, basal area per ha and volume per ha were estimated. Several regression equations between growth factors were derived using NLIN and REG procedure of SAS. And dynamic growth model, in which the equations were interactively linked, was prepared for the prediction of stand growth and yield under different management regime. The predictions of dynamic growth model were found to be coincided with general growth principles. The dynamic growth model was considered as adequate for predicting growth and yield of Pinus densiflora stand in Anmyun-Island. In practice, the dynamic growth model can be applied for predicting the growth and development of stand for various forest treatments and for decision-making in forest management.

• Development and Reproduction
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• v.17 no.4
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• pp.399-407
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• 2013

Morphological changes in the reared rock bream, Oplegnathus fasciatus, from hatching to six days after hatching were examined during the early growth stage under starvation. All the larvae died within five days when feeding was delayed for three days after hatching. These results imply that initial larval food should be supplied within two days of hatching. Changes in the pectoral angle and the ratios of eye height to head height, gut height to standard length, and gut height to myotome height in the rock bream are alternative indicators for the identification of starving fish. These indicators might prove useful in evaluating the successful transition from endogenous to exogenous feeding in this species.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.348-353
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• 2001

Experimental schemes that enable characterization of phase-change phenomena in the micro scale regime is essential for understanding the phase-change kinetics. Particularly, monitoring rapid vaporization on a submicron length scale is an important yet challenging task in a variety of laser-processing applications, including steam laser cleaning and liquid-assisted material ablation. This paper introduces a novel technique based on Michelson interferometry for probing the liquid-vaporization process on a solid surface heated by a KrF excimer laser pulse (${\lambda}=248nm,\;FWHM=24\;ns$) in water. The effective thickness of a microbubble layer has been measured with nanosecond time resolution. The maximum bubble size and growth rate are estimated to be of the order of $0.1{\mu}m\;and\;1\;m/s$, respectively. The results show that the acoustic enhancement in the laser induced vaporization process is caused by bubble expansion in the initial growth stage, not by bubble collapse. This work demonstrates that the interference method is effective for detecting bubble nucleation and microscale vaporization kinetics.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.1
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• pp.108-116
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• 1997

A laboratory experiment was made of critical transition flow modes in Czocllralski convection. Numerical computation was also made to delineate the dynamic transition. The period of temperature oscillation ($t_p$) and the interval of temperature oscillation ($\Delta\theta$) were scrutinized to capture the critical transition regime. The mixed convection parameter was varied in the range of $0.134\le Ra/PrRe^2 \le3.804$. The data from calculation were in good agreement with ones from experiment. The influence of the Prandtl number on the transition was examined for Pr ＝ 910, 4445 and 8889. To understand the transition mechanism, the detailed temperature oscillation modes, the isolines of meridional temperature and the axial velocity profiles were investigated.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1172-1177
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• 2004

The evolution of incipient soot particles has been examined by high resolution electron microscopy (HRTEM) and elemental analyzer in ethylene-air inverse diffusion flames. Laser Induced Incandescence(LII) and laser scattering methods were introduced for examining the change of soot volume fraction and morphological properties in combustion generated soot qualitatively. Soot particles, collected by thermophoretic sampling were analyzed by using HRTEM to examine the nano structure of precursor particles. HRTEM micrographs apparently reveal a transformation of condensed phase of semitransparent tar-like material into precursor particles with relatively distinct boundary and crystalline which looks like regular layer structures. During this evolution histories C/H analysis was also performed to estimate the chemical evolution of precursor particles. The changes of C/H ratio of soot particles with respect to residence time can be divided into two parts: one is a very slowly increasing regime where tar-like materials are transformed into precursor particles (inception process) the other is an increasing region with constant rate where surface growth affects the increase of C/H ratio dominantly (surface growth region). These results provide a clear picture of a transition to mature soot from precursor materials.

• Journal of the korean society of oceanography
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• v.36 no.3
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• pp.72-82
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• 2001

The progress of giant dyke construction off the Mangyung and Donajin rivers, has yielded enormous impact on the estuarine environment, both hydrodynamically and sedimentologically. Especially the inter-dyke gap in the northern Saemankeum area, 4 km wide between Yamido and Piungdo, has acted as an artificial tidal inlet. Due to such a changed geometry, tidal regime has been reversed from being flood- to ebb-dominated with a directional change from NE-SW to E-W. As a result, a large tongue-like tidal sand bar (named Saemankeum Bar) has conspicuously grown seaward through the artificial tidal inlet. The Saemankeum Bar composed of well-sorted very fine sands (3.0-3.5${\phi}$) has grown at a rate of 1.63 km/yr for the past three yews (1996-1998). Such a rapid growth of the sand bar is attributed to enhanced sediment supply derived from the degradation of former tidal sand bars at the mouth of the Mangyung River. Eventually the reworking of the tidal sand bars also caused the pre-existing tidal channels to be wider, deeper and more straightened. All of these phenomena well examplify the critical effect of artificial modifications on the natural estuarine environments.