• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.2
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• pp.70-76
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• 1990

The present study elucidates the effect of drught by polyethylene glycol solution on germination of five temperate and two tropical grasses. The results obtained can be summarized as follows: 1. The germination percentage of seven grasses decreased with increasing concentration of polythylene glycol. 2. The germination pattern hi higher concentration of polyethylene glycol showed similar trends to the emergence pattern under drought stress in soil condition. 3. The treatment of 30g is most useful at this study. Therefore, polythlene glycol was the appropriate to creat the drought condition of soil.

• Ocean and Polar Research
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• v.27 no.3
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• pp.351-358
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• 2005

Reproductive condition of the tropical blacklip pearl oyster, Pinctada margaritifera collected during the period July through September 2003 from Chuuk Lagoon, Federated State of Micronesia was investigated using histology. The level of gonad development for each pearl oyster was determined with an average score of five microscopic fields, and the average score was used as the maturity index (ML). All wild pearl oysters collected in July did exhibit fully ripe eggs in their ovaries ($45{\sim}50{\mu}M$ in diameter), indicating that they were ready for spawning. In mid August most wild pearl oysters were in spawning and M1 dropped dramatically from mid- to late September, suggesting that the wild pearl oyster completed spawning during this period. In contrast, the cultivated pearl oysters collected in mid-September held ripe eggs in the ovaries and only a few of them spawned, indicating that gonad maturation of the cultivated pearl oyster was somewhat slower than that of the wild pearl oyster in Chuuk Lagoon during the summer period. Histological analysis also indicated that spawning of the pearl oyster is rather incomplete and they may spawn continuously during summer.

• New & Renewable Energy
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• v.10 no.3
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• pp.39-46
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• 2014

The performances of three different types of photovoltaic (PV) module technologies namely, copper-indium-diselenide (CIGS), mono-crystalline silicon (mo-Si) and amorphous silicon (a-Si) have been comparatively studied in the grid-connected system for more than a year under the tropical monsoon climate of Thailand. The yields, performance ratios and system efficiencies for the respective PV module technologies have been calculated and a comparison is presented here. The performance ratios of the initial operation year for CIGS showed highest among the compared technologies under Thailand climate conditions by marking 97.0% while 89.6% for a-Si and 81.5% for mo-Si. Although mo-Si has shown highest efficiencies all over the period, under the testing conditions, the operating efficiency of mo-Si was down-graded from its reference value mainly due to high operating temperature and the efficiency of the tested CIGS module was also found as high as that of mo-Si in the study. Accordingly, outdoor assessment shows that CIGS modules have demonstrated high performance in terms of yields and performance ratios in Thailand climate conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.321-323
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• 1995

Observations were recorded regarding various fertility parameters on 26 Jersey donor cows following superovulation under tropical conditions. These cows, in their mid-luteal phase were treated with 2,500-3,000 i.u. PMSG or 28-40 mg FSH followed by $500{\mu}g$ $PGF_{2{\alpha}}$ injection 48-60 hours later, to induce oestrus. The cows were bred artificially twelve hours following standing oestrus. Embryo collection was carried out 7 days after oestrus. $PGF_{2{\alpha}}$ was injected to each donor cow after embryo recovery to regress the corpora lutea. Fertility data($PGF_{2{\alpha}}$-Oestrus interval, services per conception, days between embryo collection and successful service and any pathololgical condition) were recorded. $PGF_{2{\alpha}}$-Oestrus interval and correlation (r) between number of corpora lutea and $PGF_{2{\alpha}}$-Oestrus interval were $30.9{\pm}6.3$ and 0.17, respectively. Of 26 treated donors, 19 conceived within a period of $91.7{\pm}18.8$ days after embryo recovery. Average services per conception were $2.3{\pm}0.3$. Only two cows developed metritis which conceived after treatment with antibiotics. These observations indicated no profound adverse effect of superovulation on subsequent reproduction of donor cows, except some effect on services per conception, under tropical conditions.

• Journal of the Korean earth science society
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• v.41 no.4
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• pp.344-355
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• 2020

Tropical cyclone scale vortices and associated Rossby waves were investigated numerically using high-resolution barotropic models on the global domain. The equations of the barotropic model were discretized using the spectral transform method with the spherical harmonics function as orthogonal basis. The initial condition of the vortex was specified as an axisymmetric flow in the gradient wind balance, and four types of basic zonal states were employed. Vortex tracks showed similar patterns as those on the beta-plane but exhibited more eastward displacement as they moved northward. The zonal-mean flow appeared to control not only the west-east translation but also the meridional translation of the vortex. Such a meridional influence was revealed to be associated with the beta gyre and the Rossby wave, which are formed around the vortex due to the beta effect. In the case of the basic zonal state of climatological mean, the meridional translation speed reached the maximum value when the vortex underwent recurving.

• Journal of Climate Change Research
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• v.8 no.1
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• pp.11-19
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• 2017

This study examined the relationship between the initiation timing typhoon season in the Northwestern Pacific and the tropical sea surface temperature (SST) using a numerical simulation. The initiation timing of the typhoon season is closely associated with SSTs over the Indian Ocean (IO) and the eastern Pacific (EP) in the preceding winter and early-spring. The experiment based on the Weather and Research Forecast (WRF) model showed that the start date of the typhoon season is delayed for about one month when the SSTs over the IO and the EP increase in the preceding winter. The forced tropical SST pattern induces anticyclonic anomalies in the Northwestern Pacific, which is an unfavorable condition for typhoon development, and hence it could delay the initiation of the typhoon season.

• Wind and Structures
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• v.38 no.4
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• pp.309-323
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• 2024

The gust factor and turbulence intensity are two crucial parameters that characterize the properties of turbulence. In tropical cyclones (TCs), these parameters exhibit significant variability, yet there is a lack of established formulas to account for their probabilistic characteristics with consideration of their inherent connection. On this condition, a probabilistic analysis of gust factors and turbulence intensities of TCs is conducted based on fourteen sets of wind data collected at the Sutong Cable-stayed Bridge site. Initially, the turbulence intensities and gust factors of recorded data are computed, followed by an analysis of their probability densities across different ranges categorized by mean wind speed. The Gaussian, lognormal, and generalized extreme value (GEV) distributions are employed to fit the measured probability densities, with subsequent evaluation of their effectiveness. The Gumbel distribution, which is a specific instance of the GEV distribution, has been identified as an optimal choice for probabilistic characterizations of turbulence intensity and gust factor in TCs. The corresponding empirical models are then established through curve fitting. By utilizing the Gumbel distribution as a template, the nexus between the probability density functions of turbulence intensity and gust factor is built, leading to the development of a generalized probabilistic model that statistically describe turbulence intensity and gust factor in TCs. Finally, these empirical models are validated using measured data and compared with suggestions recommended by specifications.

• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.221-227
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• 2004

Protocol was established for production of virus free healthy seeds using meristem ($0.3-0.5\;\cal{mm}$ in size) culture and field management under net house condition in tomato. The isolated meristem was found well established in MS liquid medium containing $0.1\;\cal{mg}\;1^{-1}\;of\;GA_3$. For shoot and root development either from primary meristem or from nodal segment of meristem derived plants, semisolid MS medium having $0.5\;\cal{mg}\;1^{-1}$ of IBA was found most effective. The elimination of the studied viruses (ToMV, CMV, ToLCV) in meristem-derived plants was confirmed by DAS-ELISA test. For field management of the virus eradicated meristem-derived plants, use of net house was found very effective measures to check viral vector visit and eventually infection. The meristem-derived plants were vigor and high yielder than the native seed derived plants and produced healthy seeds. Due to stop vector visit, no viral symptoms were observed in both $R_1\;and\;R_2$ plants cultivated in net house condition. Starting of viral infestation was observed in $R_2$ generation when they were planted in open house condition without control of vector visit. Therefore, for management of viral diseases, use of virus free meristem derived plantlets and their subsequent cultivation in soil under net house condition without using any vector killing insecticide can be recommended for producing healthy seeds in tomato. The developed protocol for environmentally healthy tomato seed production in Bangladesh may be used in the countries having similar tropical like environment conducive for viral vector visit.

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.465-469
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• 2010

In order to develop effective recycling technologies of disused railway wood ties, wood properties and residual creosote oil of wood ties were investigated. Among the total 50 wood ties, 32 wood ties were identified as tropical hardwood tree, such as, Keruing (Dipterocarpus spp.), Kempas (Koompassia malaccensis), Kapur (Dryobalanops spp.) Naytoh (Palaquium rostratum), and so on. Disused wood ties showed mostly sound structure without degradation of cell walls by decay fungi. Disused wood ties showed high strengths of bending and compressive parallel to grain because degradation of wood properties was hardly occurred in use under exterior condition. Disused railway wood ties had relatively poor depth of penetration and residual of creosote oil because of refractory wood structures. These results suggest that disused railway wood ties may be useful as recycling wood wastes.

• Korean Journal of Remote Sensing
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• v.39 no.4
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• pp.441-458
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• 2023

Tropical cyclones frequently occur in the Southwest Pacific Ocean and are considered one of the driving forces for coastal alterations. Therefore, this study investigates the frequency and intensity of tropical cyclonesfrom 2000 to 2021 and their influence on the surface winds and wave conditions around the atoll nation Tuvalu. Cyclone best-track and ERA5 single-level reanalysis data are utilized to analyze the condition of the surface winds, significant wave heights, mean wave direction, and mean wave period. Additionally, the scatterometer-derived wind information was employed to compare wind conditions with the ERA5 data. On average, nine cyclones per year originated here, and the frequency increased to 11 cyclones during the last three years while the intensity decreased by 25 m/s (maximum sustained wind speed). Besides, a total of 14 cyclones were observed around Tuvalu during the period from 2015 to 2021, which showed an increase of 3 cyclones compared to the preceding period of 2001 to 2007. During cyclones, the significant wave height reached the highest 4.8 m near Tuvalu, and the waves propagated in the east-southeast direction during most of the cyclone events (52%). In addition, prolonged swells with a mean wave period of 7 to 11 seconds were generated in the vicinity of Tuvalu, for which coastal alteration can occur. After this preliminary analysis, it was found that the waves generated by cyclones have a crucial impact in altering the coastal area of Tuvalu. In the future, remotely sensed high-resolution satellite data with this wave information will be used to find out the degree of alterations that happened in the coastal area of Tuvalu before and after the cyclone events.