• Journal of Soil and Groundwater Environment
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• v.27 no.5
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• pp.1-9
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• 2022

A correlation analysis was performed to investigate differences in the response of surface water and groundwater to drought using the Standardized Precipitation Index (SPI). Water level data of 20 agricultural reservoirs, 4 dams, 2 rivers, and 8 groundwater observation wells were used for the analysis. SPI was calculated using precipitation data measured at a nearby meteorological station. The water storage of reservoirs and dams decreased significantly as they responded sensitively to the drought from 2014 to 2016, showing high correlation with SPI of the relatively long accumulation period (AP). The responses of rivers varied greatly depending on the presence of an upstream dam. The water level in rivers connected to an upstream dam was predominantly influenced by the dam discharge, resulting in very weak correlation with SPI. On the contrary, the rivers without dam exhibited a sharp water level rise in response to precipitation, showing higher correlation with SPI of a short-term AP. Unlike dams and reservoirs, the responses of groundwater levels to precipitation were very short-lived, and they did not show high correlation with SPI during the long-term drought. In drought years, the rise of groundwater level in the rainy season was small, and the lowered water level in the dry season did not proceed any further and was maintained at almost the same as that of other normal years. Conclusively, it is confirmed that groundwater is likely to persist longer than surface water even in the long-term drought years.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.2
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• pp.175-185
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• 2023

As drought risk increases due to climate change, various research works are underway around the world to respond to drought so as to minimize drought damage. In particular, in recent years, many studies are focused on analyzing regional patterns of drought in a comprehensive manner, however there is still insufficient to quantitatively identify drought-risk areas in a large river basin considering climate change in Korea. In this study, we calculated the Standardized Precipitation Index (SPI) and the Modified Standardized Precipitation Index (M_SPI) as representative meteorological drought index, and performed spatial autocorrelation analysis to identify the drought hotspot region under climate change scenarios of Representative Concentration Pathway (RCP) 4.5 and RCP 8.5. The SPI was calculated by estimating parameters for each observation station within the study area, whereas the M_SPI was calculated by estimating parameters for the entire study area. It is more reasonable to use the M_SPI for assessing meteorological drought from an overall perspective within the study area. When the M_SPI was used, long-term droughts showed drought hotspot areas clearly larger than short-term droughts. In addition, the drought hotspot area moved from the center of the Nakdong River basin to the Seomjin River basin over time. Especially, the moving patterns of the short-term/long-term drought were apparent under the RCP 4.5, whereas the moving patterns of the long-term drought were distinct under the RCP 8.5 scenarios.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.148-153
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• 2006

Effects of ${\alpha}$-chymotrypsin modification on degree of hydrolysis (DH), solubility, emulsifying capacity and thermal aggregation of laboratory-purified soy protein isolate (SPI) using a lipoxygenase-defected soybean (Jinpum-kong) and commercial soy protein isolate (Supro 500E) were compared. SPIs were hydrolyzed by ${\alpha}$-chymotrypsin at pH 7.8 and $37^{\circ}C$ for 30 min. DHs of Supro 500E and Jinpum-kong SPI were increased by ${\alpha}$-chymotrypsin modification, and DH of Supro 500E was higher than that of Jinpum-kong SPI. DH of ${\alpha}$-chymotrypsin treated Jinpum-kong SPI was similar with untreated Supro 500E and DH of treated Supro 500E was the highest. Solubility, emulsifying capacity and thermal aggregation of SPIs were increased by ${\alpha}$-chymotrypsin modification, and these changes were highly related to changes in DH. Functional properties of Supro 500E were higher than Jinpum-kong SPI in both of untreated and ${\alpha}$-chymotrypsin treated SPIs.

• Applied Biological Chemistry
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• v.35 no.3
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• pp.152-156
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• 1992

A study was condoled to investigate the effects of phosphate salts $(Na_2HPO_4\;and\;K_2HPO_4)$ on the emulsion stability of soy protein isolate (SPI) in terms of the salts concentration and addition order. When phosphates were added before emulsification, emulsion stability (ES) of SPI was improved at the concentration of 10 mM, while ES was decreased by addition of phosphates after emulsification. At high phosphate concentrations, ES of SPI was decreased by the addition of phosphates, regardless of the addition order. ES of SPI at the isoelectric point (pH 4.5) or in the presence of $CaCl_2$ was greatly enhanced by the phosphates. In both cases, the overall ES profile was found to be nearly similar to the solubility profile of SPI, indicating the positive relationship between solutibility and emulsion stability of SPI.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.669-680
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• 2017

This study evaluated the consistency of the standard flow to forecast low-flow based on various drought indices. The data used in this study were streamflow data at the Gurye2 station located in the Seomjin River and the Angang station located in the Hyeongsan River, as well as rainfall data of nearby weather stations (Namwon and Pohang). Using streamflow data, the streamflow accumulation drought index (SADI) was developed in this study to represent the hydrological drought condition. For SADI calculations, the threshold of drought was determined by a Change-Point analysis of the flow pattern and a reduction factor was estimated based on the kernel density function. Standardized runoff index (SRI) and standardized precipitation index (SPI) were also calculated to compared with the SADI. SRI and SPI were calculated for the 30-, 90-, 180-, and 270-day period and then an ROC curve analysis was performed to determine the appropriate time-period which has the highest consistency with the standard flow. The result of ROC curve analysis indicated that for the Seomjin River-Gurye2 station SADI_C3, SRI30, SADI_C1, SADI_C2, and SPI90 were confirmed in oder of having high consistency with standard flow under the attention stage and for the Hyeongsan River-Angang station, SADI_C3, SADI_C1, SPI270, SRI30, and SADI_C2 have order of high consistency with standard flow under the attention stage.

• Polymer(Korea)
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• v.36 no.4
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• pp.486-493
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• 2012

Photocurable sulfonated polyimide (SPI) polyelectrolyte containing chalcone group was prepared and fabricated on an alumina electrode pretreated with chalcone-containing silane-coupling agent. SPI films with bis(tetramethyl)ammonium 2,2'-benzidinedisulfonate ($Me_4N$-BDS)/4,4'-diaminochalcone (DAC)/pyromellitic dianhydride (PA)= 90/10/100 possessed very linear response(Y = -0.04528X+7.69446, $R^2=0.99675$) and showed resistance changing from 4.48 to $2.1k{\Omega}$ between 20 and 95 %RH. The response time for absorption and desorption measurements between 33 and 94 %RH% was about 79 s, which affirmed the high efficiency of crosslinked SPI film for rapid detection of humidity. A negative temperature coefficient showing $-0.49%RH/^{\circ}C$ was found and proper temperature compensation should be considered in future applications. Moreover, pretreatment of the substrates with chalcone-containing silane-coupling agent was performed to improve the water durability and the stability of the humidity sensors at a high humidity and a high temperature and long-term stability for 480 h. The crosslinked SPI films anchored to electrode substrate could be a promising material for the fabrication of efficient humidity sensors with superior characteristics compared to the commercially available sensors.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.9
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• pp.68-73
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• 2009

This paper presents an easily modifiable structure of a serial peripheral interface (SPI) that is suitable for efficient testing of CMOS RF integrated circuits. The proposed SPI Is designed so that the address size and the accompanying software can be easily adjusted and modified according to the requirements and complexity of RF IC's under development. The hardware architecture and software algorithm to achieve the flexibility are described. The proposed SPI is fabricated in $0.13{\mu}m$ CMOS and successfully verified experimentally with a 2.7GHz fractional-N delta-sigma frequency synthesizer as a device under test.

• Applied Chemistry for Engineering
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• v.31 no.3
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• pp.277-283
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• 2020

The smoke hazard assessment of building materials focusing on smoke performance index-II (SPI-II) and smoke growth index-II (SGI-II) was investigated. The test species used were Japanese cedar, spruce, lauan, and red pine. The smoke characteristics of wood specimen were investigated using a cone calorimeter (ISO 5660-1). SPI-II was measured after the combustion reaction increased by 1.31~2.15 times based on red pine. The fire risk by SPI-II increased in the order of spruce, lauan, Japanese ceda, and red pine. SGI-II increased by 1.18~2.55 times compared to that of Japnese ceda. The fire risk caused by SGI-II increased in the order of Japanese ceda, spruce, lauan, and red pine. CO_mean concentrations were ranged from 58 to 133 ppm, which was higher than permissible exposure limits of the occupational safety and health administration (OSHA), 50 ppm. Therefore, woods such as red pine containing various volatile organic substances, were considered to be highly smoke hazardous due to low SPI-II and high SGI-II.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.289-289
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• 2022

최근 기후변화의 영향으로 인해 가뭄과 같은 자연재해의 발생빈도가 증가하고 있다. 가뭄은 지속 기간이 길고 정량적인 피해 규모 및 심도 파악이 어려우며, 사회, 경제적 피해와 함께 농업 시스템 전반에 심각한 영향을 줄 수 있는 재해이다. 국내 가뭄 발생 경향은 2000년 이후 급증하고 있으며, 2015년 및 2017년의 경우 이례적인 극심한 가뭄이 발생하는 등 2000년 이전과는 다른 경향을 보이고 있다. 따라서, 미래 기후변화에 따른 국내 가뭄 발생에 대비하기 위해서는 장기적인 가뭄 전망이 요구된다. CMIP6 (Coupled Model Intercomparison Project 6)에 의해 개발된 공통사회경제경로 SSP (Shared Socio-economic Pathways) 시나리오는 사회 및 경제적 요소를 내포하여 미래의 완화 및 적응 기반 기후변화 시나리오로 정의된다. 본 연구에서는 SSP 시나리오를 활용하여 미래 강수자료를 구축하여 기상학적 가뭄지수, SPI (Standaridzed Precipitation Index)를 산정하고 가뭄 특성을 분석하고자 한다. 강수자료의 경우 국내 ASOS (Automated Synoptic Observing System) 기상관측소 기준 56개소를 대상으로 1973년부터 2021년까지 49개년 자료를 수집하였으며, SSP 시나리오와 SPI를 활용하여 국내 지역을 대상으로 미래 기후변화에 따른 가뭄 전망을 수행하고자 한다. SPI는 시간척도에 따라 3개월, 6개월, 9개월, 12개월 시간척도를 적용하고, SSP 시나리오의 경우 SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5 시나리오를 적용하여 미래 기후변화 시나리오별 가뭄을 분석하고자 한다.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2004.11a
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• pp.86-100
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• 2004

계산을 통한 단백질 상호작용 예측 기법의 중요성이 제기되면서 많은 단백질 상호 작용 예측 기법이 제안되고 있다. 하지만 이러한 기법들이 일반 사용자가 손쉽게 사용할 수 있는 서비스 형태로 제공되고 있는 경우는 드물다. 본 논문에서는 현재까지 알려진 단백질 상호작용 예측 기법 중 예측 기법의 완성도가 높고 상대적으로 예측 정확도가 높은 것으로 알려진 도메인 조합 기반 단백질 상호 작용 예측 기법을 PreSPI(Prediction System for Protein Interaction)라는 서비스 시스템으로 설계하고 구현하였다. 구현된 시스템이 제공하는 기능은 크게 도메인 조합 기반 단백질 상호 작용 예측 기법을 서비스 형태로 만들어 제공하는 기능으로 입력 단백질 쌍에 대한 상호작용 예측이 중심이 된 핵심기능과, 핵심 기능으로부터 파생되는 기능인 부가 기능, 그리고 주어진 단백질에 대한 도메인 정보검색 기능과 같이 단백질 상호작용에 관하여 연구하는 연구자에게 도움이 되는 일반적인 기능으로 구성되어 있다. 계산을 통해 단백질 상호 작용을 예측하는 시스템은 대규모계산이 요구되는 경우가 많아 좋은 성능을 갖추는 것이 중요하다. 본 논문에서 구현된 PreSPI 시스템은 서비스에 따라 적절히 그 처리를 병렬화 함으로써 시스템의 성능 향상을 도모하였고, PreSPI 가 제공하는 기능을 웹 서비스 API 로 Deploy 하여 시스템의 개방성을 지원하고 있다. 또한 인터넷 환경에서 변화되는 단백질 상호 작용 및 도메인에 관한 정보를 유연하게 반영할 수 있도록 시스템을 계층 구조로 설계하였다. 본 논문에서는 PreSPI 가 제공하는 몇 가지 대표적인 서비스에 관하여 사용자 인터페이스를 중심으로 상술함으로써 초기 PreSPI 사용자가 PreSPI 가 제공하는 서비스를 이해하고 사용하는 데에도 도움이 되도록 하였다.있어서 자각증상, 타각소견(他覺所見)과 함께 이상(異常)은 확인되지 않았으며 부작용도 없었다. 이상의 결과로부터, ‘펩타이드 음료’는 경증고혈압 혹은 경계역고혈압자(境界域高血壓者)의 혈압을, 자각증상 및 혈액${\cdot}$뇨검사에도 전혀 영향을 미치지 않고 저하시킨다고 결론지었다.이병엽을 염색하여 흰가루 병균의 균사생장과 포자형성 등을 관찰한 결과 균사가 용균되는 것을 볼 수 있었으며, 균사의 용균정도와 분생포자형성 억제 정도는 병 방제효과와 일치하는 경향을 보였다.을 의미한다. IV형은 가장 후기에 포획된 유체포유물이며, 광산 주변에 분포하는 석회암체 등의 변성퇴적암류로부터 $CO_{2}$ 성분과 다양한 성분의 유체가 공급되어 생성된 것으로 여겨진다. 정동이 발달하고 있지 않으며, 백운모를 함유하고 있는 대유페그마타이트는 변성작용에 의한 부분용융에 의해 형성된 멜트에서 결정화되었으며, 상당히 높은 압력의 환경에서 대유페그마타이트의 결정화작용 과정에서 용리한 유체의 성분이 전기석에 포획되어 있다. 이때 용리된 유체는 다양한 성분을 지니고 있었으며, 매우 낮은 공융온도와 다양한 딸결정은 포유물 내에 NaCl, KCl 이외에 적어도 $CaCl_{2},\;MgCl_{2}$와 같은 성분을 포함하고 있음을 지시한다. 유체의 용리는 적어도 $2.7{\sim}5.3$ kbar 이상의 압력과 $230{\sim}328^{\circ}C$ 이상의 온도에서 시작되었다.없었다. 결론적으로 일부 한방제와 생약제제는 육계에서 항생제를 대체하여 사용이 가능하며 특히 혈액의 성분에 유의한 영향을 미치는 것으로 사료된다. 실증연구가 필요할 것으로 사료된다.trip과 Sof-Lex disc로 얻어진 표면은 레진전색제의 사용으로 표면조도의 개선