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A study for diagnosis and pattern identification of Hwa-Byung (화병의 진단 및 변증유형에 관한 연구)

  • Lee, Hui-Young;Park, Jong-Hoon;Whang, Wei-Wan;Kim, Jong-Woo
    • Journal of Oriental Neuropsychiatry
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    • v.16 no.1
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    • pp.1-17
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    • 2005
  • Objective : This empirical research is performed to recognize diagnostic concept, pattern identification, and clinical features of Hwa-byung. In other words, the aims of this research are to examine the differences of the diagnosis between Hwa-Byung and the other psychiatric disorders, and to find out pattern identification, and clinical characteristics of Hwa-Byung for prescriptions of this syndrome. Method : In the experiment, there were participated 30 patients who were met for our criterions according to HBDIS (Hwa-Byung Diagnostic interview Schedule). These patients were diagnosed as Axis1 according to criterions of DSM-IV with administering SCID-I. OMS-prime was utilized for finding out pattern identification of oriental medicine. Symptom Check List-90-Revision(SCL-90-R), Hemilton rating Scale for Depression(HRSD), Heart Rate Variability(HRV), and Digital Infrared Thermographic imaging(D.I.T.I.) were also utilized to discover clinical characteristics of Hwa-Byung Patients. Results : 1. Regarding Sex-ratio, male subjects were 3(10%), and female subjects are 27(90%). The age of subjects ranged from 22 year old to 75 $(51.87{\pm}11.04;\:Mean{\pm}SD)$ 2. In the results of diagnosis on the basis of DSM-IV, the 17(56.67%) patients were MOD (Major Depressive Disorder), the 5(16.67%) patients were USD (Undifferentiated Somatoform Disorder), the 4(13.33%) patients were Dysthymic Disorder, the 3(10%) patients were GAD (Generalized Anxiety Disorder), and the 1(3.33%) was Panic Disorder. Two of the patients who diagnosed as MOD were diagnosed as Panic Disorder too, and one of them was diagnosed as Pain Disorder too. 3. Regarding pattern identification, Hwa-Byung is positively correlated to deficiency of Heart(心). and then to stagnancy of Liver-Gall bladder. Hwa-Byung is correlated deficiency symptom-complex rather than excessiveness symptom-complex. That is also correlated positively to Pathological heat and fire. 4. In SCL90-R, the mean of PSDI was $(75.3{\pm}10.7;\:Mean{\pm}SD)$. The each mean of the other 11 factors was distributed between50-70. 5. The mean of HRSD was $(17.9{\pm}5.6;\:Mean{\pm}SD)$ in the entire subject's group. Then the group of MDD was $20.9{\pm}4.4$ and the group of USD was $12.0{\pm}4.8$ 6. In the results of HRV. the mean of TP is $972.4{\pm}1174(Mean{\pm}SD)$, this is lower than normal range 1000-200. The other factors were within normal range. Then, there were no significant differences between them (p<0.05). 7. The temperatures of each acupoint have significant differences between HNl(印堂) and PC6(內關), between CV17(顫中) and PC6(內關), between HN1(印堂) and CV8(神闕), between CV17(顫中) and CV8(神闕) in comparison with the average of body temperature in the use of D.I.T.I. (p<0.01) 8. In the analysis of correlation between SCL-90-R, HRSD, HRV. and D.I.T.I. there were no significant results. According to results that the correlation was analyzed with only the MDD group as subjects, there was negative correlation between RMSSD of HRV and HRSD, between LF of HRV and PDSIof SCL-90-R, and between LF/HF of HRV and ANX, PSY, and PDSI of SCL-90-R. Conclusion : In the observation of clinical features of 30 cases of Hwa-Byung patients by using diverse structured tests, there could make diverse diagnosis as depressive disorder, anxiety disorder, and Somatoform Disorder. Particularly. MDD was highly distributed. Considering oriental medicine's pattern identification of Hwa-Byung, this syndrome is related strongly to Heart, and there were demonstrated deficiency symptom-complex, and Pathological heat and fire. One of the limits of this study is lack of control subject's group, therefore, in the future study, it requires reexamination through a comparative research with these data to complete this study.

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The Mediating Role of Perceived Risk in the Relationships Between Enduring Product Involvement and Trust Expectation (지속적 제품관여도와 소비자 요구신뢰수준 간의 영향관계: 인지된 위험의 매개 역할에 대한 실증분석을 중심으로)

  • Hong, Ilyoo B.;Kim, Taeha;Cha, Hoon S.
    • Asia pacific journal of information systems
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    • v.23 no.4
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    • pp.103-128
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    • 2013
  • When a consumer needs a product or service and multiple sellers are available online, the process of selecting a seller to buy online from is complex since the process involves many behavioral dimensions that have to be taken into account. As a part of this selection process, consumers may set minimum trust expectation that can be used to screen out less trustworthy sellers. In the previous research, the level of consumers' trust expectation has been anchored on two important factors: product involvement and perceived risk. Product involvement refers to the extent to which a consumer perceives a specific product important. Thus, the higher product involvement may result in the higher trust expectation in sellers. On the other hand, other related studies found that when consumers perceived a higher level of risk (e.g., credit card fraud risk), they set higher trust expectation as well. While abundant research exists addressing the relationship between product involvement and perceived risk, little attention has been paid to the integrative view of the link between the two constructs and their impacts on the trust expectation. The present paper is a step toward filling this research gap. The purpose of this paper is to understand the process by which a consumer chooses an online merchant by examining the relationships among product involvement, perceived risk, trust expectation, and intention to buy from an e-tailer. We specifically focus on the mediating role of perceived risk in the relationships between enduring product involvement and the trust expectation. That is, we question whether product involvement affects the trust expectation directly without mediation or indirectly mediated by perceived risk. The research model with four hypotheses was initially tested using data gathered from 635 respondents through an online survey method. The structural equation modeling technique with partial least square was used to validate the instrument and the proposed model. The results showed that three out of the four hypotheses formulated were supported. First, we found that the intention to buy from a digital storefront is positively and significantly influenced by the trust expectation, providing support for H4 (trust expectation ${\rightarrow}$ purchase intention). Second, perceived risk was found to be a strong predictor of trust expectation, supporting H2 as well (perceived risk ${\rightarrow}$ trust expectation). Third, we did not find any evidence of direct influence of product involvement, which caused H3 to be rejected (product involvement ${\rightarrow}$ trust expectation). Finally, we found significant positive relationship between product involvement and perceived risk (H1: product involvement ${\rightarrow}$ perceived risk), which suggests that the possibility of complete mediation of perceived risk in the relationship between enduring product involvement and the trust expectation. As a result, we conducted an additional test for the mediation effect by comparing the original model with the revised model without the mediator variable of perceived risk. Indeed, we found that there exists a strong influence of product involvement on the trust expectation (by intentionally eliminating the variable of perceived risk) that was suppressed (i.e., mediated) by the perceived risk in the original model. The Sobel test statistically confirmed the complete mediation effect. Results of this study offer the following key findings. First, enduring product involvement is positively related to perceived risk, implying that the higher a consumer is enduringly involved with a given product, the greater risk he or she is likely to perceive with regards to the online purchase of the product. Second, perceived risk is positively related to trust expectation. A consumer with great risk perceptions concerning the online purchase is likely to buy from a highly trustworthy online merchant, thereby mitigating potential risks. Finally, product involvement was found to have no direct influence on trust expectation, but the relationship between the two constructs was indirect and mediated by the perceived risk. This is perhaps an important theoretical integration of two separate streams of literature on product involvement and perceived risk. The present research also provides useful implications for practitioners as well as academicians. First, one implication for practicing managers in online retail stores is that they should invest in reducing the perceived risk of consumers in order to lower down the trust expectation and thus increasing the consumer's intention to purchase products or services. Second, an academic implication is that perceived risk mediates the relationship between enduring product involvement and trust expectation. Further research is needed to elaborate the theoretical relationships among the constructs under consideration.

A Study on Dose-Response Models for Foodborne Disease Pathogens (주요 식중독 원인 미생물들에 대한 용량-반응 모델 연구)

  • Park, Myoung Su;Cho, June Ill;Lee, Soon Ho;Bahk, Gyung Jin
    • Journal of Food Hygiene and Safety
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    • v.29 no.4
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    • pp.299-304
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    • 2014
  • The dose-response models are important for the quantitative microbiological risk assessment (QMRA) because they would enable prediction of infection risk to humans from foodborne pathogens. In this study, we performed a comprehensive literature review and meta-analysis to better quantify this association. The meta-analysis applied a final selection of 193 published papers for total 43 species foodborne disease pathogens (bacteria 26, virus 9, and parasite 8 species) which were identified and classified based on the dose-response models related to QMRA studies from PubMed, ScienceDirect database and internet websites during 1980-2012. The main search keywords used the combination "food", "foodborne disease pathogen", "dose-response model", and "quantitative microbiological risk assessment". The appropriate dose-response models for Campylobacter jejuni, pathogenic E. coli O157:H7 (EHEC / EPEC / ETEC), Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococcus aureus, Vibrio parahaemolyticus, Vibrio cholera, Rota virus, and Cryptosporidium pavum were beta-poisson (${\alpha}=0.15$, ${\beta}=7.59$, fi = 0.72), beta-poisson (${\alpha}=0.49$, ${\beta}=1.81{\times}10^5$, fi = 0.67) / beta-poisson (${\alpha}=0.22$, ${\beta}=8.70{\times}10^3$, fi = 0.40) / beta-poisson (${\alpha}=0.18$, ${\beta}=8.60{\times}10^7$, fi = 0.60), exponential (r=$1.18{\times}10^{-10}$, fi = 0.14), beta-poisson (${\alpha}=0.11$, ${\beta}=6,097$, fi = 0.09), beta-poisson (${\alpha}=0.21$, ${\beta}=1,120$, fi = 0.15), exponential ($r=7.64{\times}10^{-8}$, fi = 1.00), betapoisson (${\alpha}=0.17$, ${\beta}=1.18{\times}10^5$, fi = 1.00), beta-poisson (${\alpha}=0.25$, ${\beta}=16.2$, fi = 0.57), exponential ($r=1.73{\times}10{-2}$, fi = 1.00), and exponential ($r=1.73{\times}10^{-2}$, fi = 0.17), respectively. Therefore, these results provide the preliminary data necessary for the development of foodborne pathogens QMRA.

A Technique Assessing Geological Lineaments Using Remotely Sensed Data and DEM : Euiseons Area, Kyungsang Basin (원격탐사자료와 수치표고모형을 이용한 지질학적 선구조 분석기술: 경상분지 의성지역을 중심으로)

  • 김원균;원중선;김상완
    • Korean Journal of Remote Sensing
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    • v.12 no.2
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    • pp.139-154
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    • 1996
  • In order to evaluate the sensor`s look direction bias in the Landsat TM image and to estimate trends of primary geological lineaments, we have attempted to systematically compare lineaments in TM image, relief shadowed DEM's, and actual lineaments of geologic and topographic map through the Hough transform technique. Hough transform is known to be very effective to estimate the trend of geological lineaments, and help us to obtain the true trends of lineaments. It is often necessary to compensate the preferential enhancements of terrain lineaments in a TM image occurred by to look direction bias, and that can be achieved by utilizing an auxiliary data. In this study, we have successfully adopted the relief shadowed DEM in which the illuminating azimuth angle is perpendicular to look direction of a TM image for assessing true trends of geological lineaments. The results also show that the sum of four relief shadowed DEM's directional components can possibly be used as an alternative. In Euiseong-gun area where Sindong Group and Mayans Group are mainly distributed, geological lineaments trending $N5^{\circ}$~$10^{\circ}$W are dominant, while those of $N55^{\circ}$~$65^{\circ}$ W are major trends in Cheongsong-gun area where Hayang Group, Yucheon Group and Bulguksa Granite are distributed. Using relief shadowed DEM as an auxiliary data, we found the $N55^{\circ}$~$65^{\circ}$ W lineaments which are not cleanly observed in TM image over Euiseong-gun area. Compared with the trend of Gumchon and Gaum strike-slip faults, these lineaments are considered to be an extension of the faults. Therefore these strike-slip faults possibly extend up to Sindong Group in the northwest parts in the study area.

DEM Generation over Coastal Area using ALOS PALSAR Data - Focus on Coherence and Height Ambiguity - (ALOS PALSAR 자료를 이용한 연안지역의 DEM 생성 - 긴밀도와 고도 민감도 분석을 중심으로 -)

  • Choi, Jung-Hyun;Lee, Chang-Wook;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.23 no.6
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    • pp.559-566
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    • 2007
  • The generation of precise digital elevation model (DEM) is very important in coastal area where time series are especially required. Although a LIDAR system is useful in coastal regions, it is not yet popular in Korea mainly because of its high surveying cost and national security reasons. Recently, precise DEM has been made using radar interferometry and waterline methods. One of these methods, spaceborne imaging radar interferometry has been widely used to measure the topography and deformation of the Earth. We acquired ALOS PALSAR FBD mode (Fine Beam Dual) data for evaluating the quality of interferograms and their coherency. We attempted to construct DEM using ALOS PALSAR pairs - One pair is 2007/05/22 and 2007/08/22, another pair is 2007/08/22 and 2007/10/22 with respective perpendicular baseline of 820 m, 312m and respective height sensitivity of 75 m and 185m at southern of Ganghwa tidal flat, Siwha- and Hwaong-lake over west coastal of Korea peninsula. Ganghwa tidal flat has low coherence between 0.3 and 0.5 of 2007/05/22 and 2007/08/22 pair. However, Siwha-lake and Hwaong-lake areas have a higher coherence value (From 0.7 and 0.9) than Ganghwa tidal area. The reason of difference coherence value is tidal condition between tidal flat area (Ganghwa) and reclaimed zone (Siwha-lake and Hwaong-lake). Therefore, DEM was constructed by ALOS PALSAR pair over Siwha-lake and Hwaong-lake. If the temporal baseline is enough short to maintain the coherent phases and height sensitivity is enough small, we will be able to successfully construct a precise DEM over coastal area. From now on, more ALOS PALSAR data will be needed to construct precise DEM of West Coast of Korea peninsular.

Effects on the Thermal Change of the Face Follow Electroacupunctyre on Hapkok($LI_4$), Sangan($LI_3$) (合谷($LI_4$), 三間($LI_3$)의 電針刺戟이 顔面部 領域 溫度變化에 미치는 影響)

  • Yun, Jeong-hun;Kim, Jong-Han;Hwang, Chung-yeon;Lim, Kyu-sang
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.12 no.2
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    • pp.222-247
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    • 1999
  • The back ground and purpose : The acupuncture of oriental medicine is very important in treatments. Until now it has been researched according to the meridian and qi xue(氣血) phenomenon of oriental medicine's theory. As electroacupuncture is one of acupuncture treatments, it will show more objective index to observe the meridian and qi xue(氣血) phenomenon. And then, I studied the effects on the thermal change of the face following electroacupuncture treatment. Objective and Methods : This study was performed from January 1999 to March 1999 on 10 healthy students. The objective was divided into three groups, those were the control group A(n=10), the group B(n=10) of electroacupuncture on Hapkok($LI_4$), Samgan($LI_3$) and the group C(n=10) of electroacupuncture on Shinmun($H_7$), T' ongni($H_5$). First, in the control group A, we took a picture for 10 men without any stimulation with the Digital Infrared Thermograph Imaging(D.I.T.I.) and did 3min after, 10min after, 15min after, 25min after, 45min after respectively. Second, in the electroacupuncture treatment group B, we took a picture for 10 men without any stimulation, and then treat electroacupuncture on Hapkok($LI_4$), Samgan($LI_3$) and took a picture immediately(3min after), 10min after, 15min after and remove needle and took a picture in the same way respectively. Third, in the electroacupuncture treatment group C, we took a picture for 10 men without any stimulation, and then treat electroacupuncture on Shinmun($H_7$), T'ongni($H_5$) and took a picture in the second way respectively. Results: 1. In healthy men, average skin temperture about Yonghyang($LI_{20}$) area was higher than Soryo($G_{25}$) or Chich'ang($S_4$) area. They were Soryo($G_{25}$) area $31.495{\pm}0.766^{\circ}C$, Rt. Yonghyang($LI_{20}$) area $31.664{\pm}0.936^{\circ}C$, Lt. Yonghyang ($LI_{20}$)area $31.686{\pm}0.767^{\circ}C$, Rt. Chich'ang($S_4$) area $31.226{\pm}0.875^{\circ}$, Lt. Chich'ang ($S_4$) area $31.453{\pm}0.855^{\circ}C$. 2. In the control group A, the skin temperature of Soryo($G_{25}$) showed the increase or decrease in below ${\Delta}0.1^{\circ}C\;except\;0.265{\pm}0.594^{\circ}C$ in 25min, but not significantly. 3. About Soryo($G_{25}$) area, the skin temperature decreased significantly after electroacupuncture immediately. ${\Delta}T $of the group B was $-0.970{\pm}0.87\;1^{\circ}C$, which was larger than one of the group C which was $-0.707{\pm}0.624^{\circ}C$ at 3min. And then ${\Delta}T$ of the group C was increase valuable at 25min, 45min. 4. About Yonghyang($L1_{25}$) area, the left ${\Delta}T$ of the group B showed below $0.2^{\circ}C$ or so in contrast to the right it. In the group C, on the both side showed continous increase of temperature as following times. 5. About Chich'ang($S_4$) area, the skin temperature increased valuable $0.3^{\circ}C$ or so on the both side and later inclined to decrease in the group B but not significantly. In the group C, it increased valuable on the both side. 6. The skin temperature of electroacupuncture treatment group B, C were more increase than the control group A except Lt. Yonghyang($LI_{20}$) area in the group B. The temperature of group C were more increase than the group B wholly. Conclusion : The above results indicate that D.I.T.I. is a useful method to observe and fallow-up the effects and the changes by electroacupuncture stimulation on objective evaluation of phenomenon for the meridian system and character. Thus, continuous thermographic study will be needed for more clinical application such as acupuncture and medicine or laser therapy according to oriental medicine.

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Prediction of Soil Erosion from Agricultural Uplands under Precipitation Change Scenarios (우리나라 강우량 변화 시나리오에 따른 밭토양의 토양 유실량 변화 예측)

  • Kim, Min-Kyeong;Hur, Seong-Oh;Kwon, Soon-Ik;Jung, Goo-Bok;Sonn, Yeon-Kyu;Ha, Sang-Keun;Lee, Deog-Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.6
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    • pp.789-792
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    • 2010
  • Major impacts of climate change expert that soil erosion rate may increase during the $21^{st}$ century. This study was conducted to assess the potential impacts of climate change on soil erosion by water in Korea. The soil loss was estimated for regions with the potential risk of soil erosion on a national scale. For computation, Universal Soil Loss Equation (USLE) with rainfall and runoff erosivity factors (R), cover management factors (C), support practice factors (P) and revised USLE with soil erodibility factors (K) and topographic factors (LS) were used. RUSLE, the revised version of USLE, was modified for Korean conditions and re-evaluate to estimate the national-scale of soil loss based on the digital soil maps for Korea. The change of precipitation for 2010 to 2090s were predicted under A1B scenarios made by National Institute of Meteorological Research in Korea. Future soil loss was predicted based on a change of R factor. As results, the predicted precipitations were increased by 6.7% for 2010 to 2030s, 9.5% for 2040 to 2060s and 190% for 2070 to 2090s, respectively. The total soil loss from uplands in 2005 was estimated approximately $28{\times}10^6$ ton. Total soil losses were estimated as $31{\times}10^6$ ton in 2010 to 2030s, $31{\times}10^6$ ton in 2040 to 2060s and $33{\times}10^6$ ton in 2070 to 2090s, respectively. As precipitation increased by 17% in the end of $21^{st}$ century, the total soil loss was increased by 12.9%. Overall, these results emphasize the significance of precipitation. However, it should be noted that when precipitation becomes insignificant, the results may turn out to be complex due to the large interaction among plant biomass, runoff and erosion. This may cause increase or decrease the overall erosion.

Development of Greenhouse Cooling and Heating Load Calculation Program Based on Mobile (모바일 기반 온실 냉난방 부하 산정 프로그램 개발)

  • Moon, Jong Pil;Bang, Ji Woong;Hwang, Jeongsu;Jang, Jae Kyung;Yun, Sung Wook
    • Journal of Bio-Environment Control
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    • v.30 no.4
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    • pp.419-428
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    • 2021
  • In order to develope a mobile-based greenhouse energy calculation program, firstly, the overall thermal transmittance of 10 types of major covers and 16 types of insulation materials were measured. In addition, to estimate the overall thermal transmittance when the cover and insulation materials were installed in double or triple layers, 24 combinations of double installations and 59 combinations of triple installations were measured using the hotbox. Also, the overall thermal transmittance value for a single material and the thermal resistance value were used to calculate the overall thermal transmittance value at the time of multi-layer installation of covering and insulating materials, and the linear regression equation was derived to correct the error with the measured values. As a result of developing the model for estimating thermal transmittance when installing multiple layers of coverings and insulating materials based on the value of overall thermal transmittance of a single-material, the model evaluation index was 0.90 (good when it is 0.5 or more), indicating that the estimated value was very close to the actual value. In addition, as a result of the on-site test, it was evaluated that the estimated heat saving rate was smaller than the actual value with a relative error of 2%. Based on these results, a mobile-based greenhouse energy calculation program was developed that was implemented as an HTML5 standard web-based mobile web application and was designed to work with various mobile device and PC browsers with N-Screen support. It had functions to provides the overall thermal transmittance(heating load coefficient) for each combination of greenhouse coverings and thermal insulation materials and to evaluate the energy consumption during a specific period of the target greenhouse. It was estimated that an energy-saving greenhouse design would be possible with the optimal selection of coverings and insulation materials according to the region and shape of the greenhouse.

Groundwater Recharge Evaluation on Yangok-ri Area of Hongseong Using a Distributed Hydrologic Model (VELAS) (분포형 수문모형(VELAS)을 이용한 홍성 양곡리 일대 지하수 함양량 평가)

  • Ha, Kyoochul;Park, Changhui;Kim, Sunghyun;Shin, Esther;Lee, Eunhee
    • Economic and Environmental Geology
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    • v.54 no.2
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    • pp.161-176
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    • 2021
  • In this study, one of the distributed hydrologic models, VELAS, was used to analyze the variation of hydrologic elements based on water balance analysis to evaluate the groundwater recharge in more detail than the annual time scale for the past and future. The study area is located in Yanggok-ri, Seobu-myeon, Hongseong-gun, Chungnam-do, which is very vulnerable to drought. To implement the VELAS model, spatial characteristic data such as digital elevation model (DEM), vegetation, and slope were established, and GIS data were constructed through spatial interpolation on the daily air temperature, precipitation, average wind speed, and relative humidity of the Korea Meteorological Stations. The results of the analysis showed that annual precipitation was 799.1-1750.8 mm, average 1210.7 mm, groundwater recharge of 28.8-492.9 mm, and average 196.9 mm over the past 18 years from 2001 to 2018 in the study area. Annual groundwater recharge rate compared to annual precipitation was from 3.6 to 28.2% with a very large variation and average 14.9%. By the climate change RCP 8.5 scenario, the annual precipitation from 2019 to 2100 was 572.8-1996.5 mm (average 1078.4 mm) and groundwater recharge of 26.7-432.5 mm (average precipitation 16.2%). The annual groundwater recharge rates in the future were projected from 2.8% to 45.1%, 18.2% on average. The components that make up the water balance were well correlated with precipitation, especially in the annual data rather than the daily data. However, the amount of evapotranspiration seems to be more affected by other climatic factors such as temperature. Groundwater recharge in more detailed time scale rather than annual scale is expected to provide basic data that can be used for groundwater development and management if precipitation are severely varied by time, such as droughts or floods.

A Study of a Correlation Between Groundwater Level and Precipitation Using Statistical Time Series Analysis by Land Cover Types in Urban Areas (시계열 분석법을 이용한 도시지역 토지피복형태에 따른 지하수위와 강수량의 상관관계 분석)

  • Heo, Junyong;Kim, Taeyong;Park, Hyemin;Ha, Taejung;Kang, Hyungbin;Yang, Minjune
    • Korean Journal of Remote Sensing
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    • v.37 no.6_2
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    • pp.1819-1827
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    • 2021
  • Land-use/cover change caused by rapid urbanization in South Korea is one of the concerns in flood risk management because groundwater recharge by precipitation hardly occurs due to an increase in impermeable surfaces in urban areas. This study investigated the hydrologic effects of land-use/cover on groundwater recharge in the Yeonje-gu district of Busan, South Korea. A statistical time series analysis was conducted with temporal variations of precipitation and groundwater level to estimate lag-time based on correlation coefficients calculated from auto-correlation function (ACF), cross-correlation function (CCF), and moving average (MA) at five sites. Landform and land-use/cover within 250 m radius of the monitoring wells(GW01, GW02, GW03, GW04, and GW05) at five sites were identified by land cover and digital map using Arc-GIS software. Long lag-times (CCF: 42-71 days and MA: 148-161 days) were calculated at the sites covered by mainly impermeable surfaces(GW01, GW03, and GW05) while short lag-times(CCF: 4 days and MA: 67 days) were calculated at GW04 consisting of mainly permeable surfaces. The results suggest that lag-time would be one of the good indicators to evaluate the effects of land-use/cover on estimating groundwater recharge. The results of this study also provide guidance on the application of statistical time series analysis to environmentally important issues on creating an urban green space for natural groundwater recharge from precipitation in the city and developing a management plan for hydrological disaster prevention.