• Earthquakes and Structures
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• v.20 no.1
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• pp.39-53
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• 2021

By means of installing sloped rolling-type seismic isolators (SRI), the horizontal acceleration transmitted to the to-be-protected object above can be effectively and significantly reduced under external disturbance. To prevent the maximum horizontal displacement response of SRI from reaching a threshold, designing large and conservative damping force for SRI might be required, which will also enlarge the transmitted acceleration response. In a word, when adopting seismic isolation, minimizing acceleration or displacement responses is always a trade-off. Therefore, this paper proposes that by exploiting the possible information provided by an earthquake early warning system, the damping force applied to SRI which can better control both acceleration and displacement responses might be determined in advance and accordingly adjusted in a semi-active control manner. By using a large number of ground motion records with peak ground acceleration not less than 80 gal, the numerical results present that the maximum horizontal displacement response of SRI is highly correlated with and proportional to some important parameters of input excitations, the velocity pulse energy rate and peak velocity in particular. A control law employing the basic form of hyperbolic tangent function and two objective functions are considered in this study for conceptually developing suitable control algorithms. Compared with the numerical results of simply designing a constant, large damping factor to prevent SRI from pounding, adopting the recommended control algorithms can have more than 60% reduction of acceleration responses in average under the excitations. More importantly, it is effective in reducing acceleration responses under approximately 98% of the excitations.

• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.2
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• pp.201-203
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• 2008

A field study on self trap cropping system in controlling tukra mealy bug Maconellicoccus hirsutus Green) incidence on mulberry (Morus spp.; V-1 variety; $3'{\times}3'$ spacing) gardens was undertaken in selected sericulture farmers' mulberry gardens of Pydeti village (Parigi Mandal, Anantapur District, Andhra Pradesh, India). The study was conducted for three years (2004, 2005 and 2006). Four treatments (T0; control/no treatment, T1; self trap cropping rows with 10 row interval, T2; self trap cropping rows with 10 row interval and treating these rows only with 0.5% neem oil emulsion and T3; self trap cropping rows with 10 rows intervals and treating all the mulberry rows including self trap cropping rows with 0.5% neem oil emulsion) were considered. The results indicated that the incidence increased in T0 and T1 while the same suppressed in T2 and T3. The suppression (%) of tukra incidence between T2 and T3 was not significant. Hence, T2 only was recommended to farmers as its economical viable practice. The results are discussed based on the importance of tukra, its suppression and cost of treatment.

• Bulletin of the Korea Photovoltaic Society
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• v.6 no.1
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• pp.21-34
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• 2020

Sri Lanka has strongly understood the importance of mitigation of climate change and various measures have been taken. To tackle the climate change, after ratifying Paris Agreement, Sri Lanka has pledged to reduce her greenhouse gas emission in the energy sector by 20% (16% unconditional and 4% conditional) by 2030 based on the BAU scenario. Simultaneously, the government introduced its new energy policy and strategies in 2019 with a vision of achieving carbon neutrality by 2050. This paper survey related key government documents, policies, reports, and academic articles to investigate opportunities for the private sector to invest large scale solar power deployment (10 MW or above) and to get support from climate finance under article 6 of the Paris Agreement. It has found, growing concern on the environment, energy security issues and increase import expenses for fossil fuels are the main influencing factors to move renewable sources. Further, government investment and FDI both have gradually decreased in the energy sector. Therefore, an alternative financing mechanism is needed. Although the private sector allowed investing in the energy sector since 1996 with the introduction of IPP (Independent Power Producers), it could not make considerable progress on involving large scale solar utility projects. This has revealed government policy is not aligning with the long term generation plan of the electricity sector. The study has also found, it needs more strategic road map, coordination with different institutions, monitoring system to enhance large scale solar contribution.

• Child Health Nursing Research
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• v.26 no.1
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• pp.72-81
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• 2020

Purpose: This study was conducted to investigate nurses' perceptions and performance of family-centered care (FCC) at a children's hospital in Sri Lanka and to explore the feasibility of implementing FCC in the context of the Sri Lankan healthcare system. Methods: A convergent, parallel, mixed-methods design was applied to understand Sri Lankan nurses' perspectives on FCC. In total, 157 nurses working at a large teritagy children's hospital responded to a self-report survey and 18 nurses participated in focus group interviews. Results: Of the factors of FCC, family participation in caring for children received the highest score (4.09±0.51) for perceptions, and information-sharing received the highest score (3.54±0.55) for performance. The qualitative data revealed the following five themes: (a) importance of the family in caring for children; (b) helping families during children's hospitalization; (c) taking steps to implement FCC, even with imperfect knowledge; (d) barriers in the current situation; and (e) suggested strategies to promote FCC. Conclusion: Participants endorsed the concept of FCC and demonstrated some aspects of it in their day-to-day practice. The results indicate a clear knowledge deficit and several challenges, which need to be addressed to effectively implement FCC.

• Atmosphere
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• v.25 no.2
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• pp.271-281
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• 2015

The objectives of this study are to develop a hydrological drought outlook system using GloSea5 (Global Seasonal forecasting system 5) which has recently been used by KMA (Korea Meteorological Association) and to evaluate the forecasting capability. For drought analysis, the bilinear interpolation method was applied to spatially downscale the low-resolution outputs of GloSea5 and PR (Predicted Runoff) was produced for different lead times (i.e., 1-, 2-, 3-month) running LSM (Land Surface Model). The behavior of PR anomaly was similar to that of HR (Historical Runoff) and the estimated values were negative up to lead times of 1- and 2-month. For the evaluation of drought outlook, SRI (Standardized Runoff Index) was selected and PR_SRI estimated using PR. ROC score was 0.83, 0.71, 0.60 for 1-, 2- and 3-month lead times, respectively. It also showed the hit rate is high and false alarm rate is low as shorter lead time. The temporal Correlation Coefficient (CC) was 0.82, 0.60, 0.31 and Root Mean Square Error (RMSE) was 0.52, 0.86, 1.20 for 1-, 2-, 3-month lead time, respectively. The accuracy of PR_SRI was high up to 1- and 2-month lead time on local regions except the Gyeonggi and Gangwon province. It can be concluded that GloSea5 has high applicability for hydrological drought outlook.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.18-26
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• 2004

This study evaluated the impact of an AI heifer calf rearing scheme on dairy stock development, in a coconut grazing and a peri-urban smallholder dairy production system in the Western Province of Sri Lanka. The heifer rearing scheme included free advice on calf rearing, drugs, acaricides, minerals and subsidised concentrates for 30 months. The farmers in the coconut growing area integrate dairying with their plantation, they sell their milk to the main processors. The peri-urban farmers are intensive milk producers, who sell their milk at informal markets. To estimate the effect of the heifer rearing scheme on dairy replacement stock development, scheme farmers were compared with farmers who did not participate in the scheme. Calf mortality was twice as high in non-scheme farms (23-28%) as in scheme farms (12-14%). The scheme had a positive effect on weight development and scheme heifers calved 4.5 months earlier than non-scheme heifers. The calf rearing package is cost effective in both farming systems, however, the required cash inputs are a major constraint. The costs per in-calf heifer under the scheme are much lower than the production of such animals by either multiplication in state farms or importing them. The coconut grazing system showed the highest potential for producing surplus dairy stock.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.123-123
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• 2018

가뭄은 홍수와 달리 진행속도가 비교적 느리기 때문에 초기에 감지한다면 피해를 최소화 할 수 있다. 국내에서는 가뭄전망을 위해 물리적 기반의 기상-수문연계해석 시스템을 구축하여 월 내지 계절전망을 수행하고 있다. 물리적 기반의 가뭄전망은 수치예보모델의 불확실성을 가지고 있으므로 예보 정확도 개선의 측면에서는 통계적 모델을 같이 활용하는 것이 바람직하다. 최근 국외에서는 통계적 방법인 AI (Artificial Intelligence) 기술을 사용하여 가뭄을 전망하는 연구가 활발히 진행 중이나, 아직까지 국내에서는 관련연구가 미흡한 실정이다. 이에 본 연구에서는 ANFIS (Adaptive Neuro-Fuzzy Inference System) 기반의 댐 유입량 예측 모델을 구축하고 SRI (Standardized Runoff Index)를 활용하여 수문학적 가뭄전망을 수행하였다. 대상유역은 국내 주요 다목적댐이 위치한 충주댐 유역과 소양강댐 유역을 선정하였다. 수문 및 기상자료는 국토 교통부 및 기상청의 관측 댐 유입량, 관측 강수량, 관측 기온 및 장기기상예보 자료를 사용하였다. ANFIS 모델 구축을 위한 훈련 및 보정기간과 검정기간은 각각 1987~2010년과 2011~2016년을 선정하였다. 수문학적 가뭄전망은 지속기간 3개월의 1개월 전망 SRI3를 활용하였으며, SRI3는 관측유입량과 예측유입량을 결합하여 산정하였다. 댐 예측유입량 및 수문학적 가뭄전망의 정확도 평가를 위해 상관계수, 평균제곱근오차를 활용하였다. 댐 예측유입량 평가 결과 예측값과 관측값의 상관계수가 높게 나타났으며, 평균제곱근오차는 낮아 예측성이 뛰어났다. SRI3의 경우 관측값과 예측값의 가뭄발생시기가 유사하여 가뭄을 적절하게 반영하는 것으로 나타났다. 본 연구의 결과는 통계적 기반의 수문학적 가뭄전망기법을 개발하였다는 측면에서 의의가 있으며, 향후 물리적 기반의 가뭄전망정보와 결합한다면 보다 실효성이 향상될 것으로 기대된다.

• Atmosphere
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• v.23 no.1
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• pp.113-121
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• 2013

The objective of this study is to develop and evaluate the system to produce the real-time ensemble drought prediction data. Ensemble drought prediction consists of 3 processes (meteorological outlook using the multi-initial conditions, hydrological analysis and drought index calculation) therefore, more processing time and data is required than that of single member. For ensemble drought prediction, data process time is optimized and hardware of existing system is upgraded. Ensemble drought data is estimated for year 2012 and to evaluate the accuracy of drought prediction data by using ROC (Relative Operating Characteristics) analysis. We obtained 5 ensembles as optimal number and predicted drought condition for every tenth day i.e. 5th, 15th and 25th of each month. The drought indices used are SPI (Standard Precipitation Index), SRI (Standard Runoff Index), SSI (Standard Soil moisture Index). Drought conditions were determined based on results obtained for each ensemble member. Overall the results showed higher accuracy using ensemble members as compared to single. The ROC score of SRI and SSI showed significant improvement in drought period however SPI was higher in the demise period. The proposed ensemble drought prediction system can be contributed to drought forecasting techniques in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3395-3403
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• 2016

Conjugated linoleic acid, a functional lipid, produced from Lactobacillus plantarum (LP-CLA), has been demonstrated to possess apoptotic activity. The anti-proliferative and apoptotic potential of LP-CLA was here evaluated in vitro using the MDA-MB-231 human breast cancer cell line as a model system. Proliferation of MDA-MB-231 cells was inhibited with increasing concentrations of LP-CLA with altered morphological features like cell detachment, rounding of cells and oligonucleosomal fragmentation of DNA. Flow cytometry confirmed the apoptotic potential of LP-CLA by ANNEXIN V/PI double staining. Furthermore, outcome results indicated that the apoptosis was mediated by downregulation of the NF-${\kappa}B$ pathway which in turn acted through proteasome degradation of $I{\kappa}B{\alpha}$, inhibition of p65 nuclear translocation, release of cytochrome-C from mitochondria and finally overexpression of Bax protein. Thus, conjugated linoleic acid, a natural product derived from probiotics, could therefore be a possible potential chemotherapeutic agent due to its apoptotic activity against estrogen receptor negative breast cancer cells.

• Journal of Korea Water Resources Association
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• v.48 no.7
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• pp.581-593
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• 2015

This study constructs the drought outlook system using ESP(Ensemble Streamflow Prediction) method and evaluates its utilization for drought prediction. Historical Runoff(HR) was estimated by employing LSM(Land Surface Model) and the observed meteorological, hydrological and topographical data in South Korea. Also Predicted Runoff(PR) was produced for different lead times(i.e. 1-, 2-, 3-month) using 30-year past meteorological data and the initial soil moisture condition. The HR accuracy was higher during MAM, DJF than JJA, SON, and the prediction accuracy was highly decreased after 1 month outlook. SRI(Standardized Runoff Index) verified for the feasibility of domestic drought analysis was used for drought outlook, and PR_SRI was evaluated. The accuracy of PR_SRI with lead times of 1- and 2-month was highly increased as it considered the accumulated 1- and 2-month HR, respectively. The Correlation Coefficient(CC) was 0.71, 0.48, 0.00, and Root Mean Square Error(RMSE) was 0.46, 0.76, 1.01 for 1-, 2- and 3-month lead times, respectively, and the accuracy was higher in arid season. It is concluded that ESP method is applicable to domestic drought prediction up to 1- and 2-month lead times.