• Weed & Turfgrass Science
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• v.6 no.1
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• pp.11-20
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• 2017

Ninety species belonging to 28 families of weeds were identified in Korean rice fields. They were divided by eight provinces and 19 agro-climatic zones to be used as basic data of weed control. Looking at the regional weed occurrence, there were 52 species of 20 families in Gyeonggi, 37 species of 17 families in Gangwon, 41 species of 15 families in Chungbuk, 21 species of 12 families in Chungnam, 24 species of 13 families in Jeonbuk, 54 species of 21 families in Chonnam, 36 species of 20 families in Gyeongbuk, and 32 species of 16 families in Gyeongnam province, respectively. The most dominant family was Poaceae followed by Cyperaceae and Asteraceae. Mostly dominant species were Echinochloa spp., Monochoria vaginalis var. plantaginea, Scirpus juncoides var. hotarui, Eleocharis kuroguwai, and Sagittaria sagittifolia subsp. leucopetala with slight differences among the provinces. Although there were some differences in 18 climate zones from Taebaek sub-highlands to the southern part of the East Coast (except for the Taebaek Highland), the dominant species were Echinochloa spp., Monochoria vaginalis var. plantaginea and Scirpus juncoides var. hotarui. The most dominant family was Cyperaceae followed by Poaceae and Asteraceae. The differences of weed occurrence between provinces and agro-climatic zones were largely influenced by various weather conditions rather than the provinces. The changes in cultivation mode and herbicide use might influence as well.

• Journal of the Korean GEO-environmental Society
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• v.19 no.10
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• pp.13-19
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• 2018

Following the 2016 Gyeongju earthquake, the Pohang Earthquake occurred in 2017, and the south-east region in Korea is under the threat of an earthquake. Especially, in the Pohang Earthquake, the liquefaction phenomenon occurred in the sedimentation area of the coast, and preparation of countermeasures is very important. The soil liquefaction can affect the underground facilities directly as well as various structures on the ground. Therefore, it is necessary to identify the liquefaction risk of facilities and the structures against the possible earthquakes and to prepare countermeasures to minimize them. In this study, we investigated the seismic liquefaction risk about the electric power utility tunnels in the southeast area where the earthquake occurred in Korea recently. In the analysis of seismic liquefaction risk, the earthquake with return period 1000 years and liquefaction potential index are used. The liquefaction risk analysis was conducted in two stages. In the first stage, the liquefaction risk was analyzed by calculating the liquefaction potential index using the ground survey data of the location of electric power utility tunnels in the southeast region. At that time, the seismic amplification in soil layer was considered by soil amplification factor according to the soil classification. In the second stage, the liquefaction risk analysis based on the site response analyses inputted 3 earthquake records were performed for the locations determined to be dangerous from the first step analysis, and the final liquefaction potential index was recalculated. In the analysis, the site investigation data were used from the National Geotechnical Information DB Center. Finally, it can be found that the proposed two stage assessments for liquefaction risk that the macro assessment of liquefaction risk for the underground facilities including the electric power utility tunnel in Korea is carried out at the first stage, and the second risk assessment is performed again with site response analysis for the dangerous regions of the first stage assessment is reasonable and effective.

• Journal of the Korean earth science society
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• v.28 no.4
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• pp.478-490
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• 2007

With groundwater data of seawater intrusion monitoring network in coastal areas of Korea's main land, we analyzed types of seawater intrusion through the coastal aquifer. The data including groundwater level, temperature and electrical conductivity obtained from 45 monitoring wells at 25 watershed regions were evaluated. Based on statistical analysis, correlation analysis and variation type analysis, groundwater levels were mainly affected by rainfall and artificial pumping. About 78% of the monitoring wells showed average temperature higher than $15^{\circ}C$ and about 58% of them showed minimum variations less than $0.2^{\circ}C$. Electrical conductivities showed a large magnitude of variation and irregular characteristics compared with groundwater levels and temperatures. Average electrical conductivities lower than $2,000\;{\mu}S/cm$ were observed at 28 monitoring wells while those of higher than $10,000\;{\mu}S/cm$ were done at 9 monitoring wells. From the cross-correlation analysis, groundwater levels were mostly affected by precipitation while temperature and electrical conductivity showed very low correlation. Meanwhile tidal variations strongly affected the groundwater levels comparing to precipitation. We classified the long-term monitoring data according to variation types such as constant process, linear trend, cyclic variation, impulse, step function and ramp. Impulse type was dominant for variations of groundwater level, which was largely affected by rainfall or artificial pumping, the constant process was dominant for temperature. Compared with groundwater level and temperature, electrical conductivities showed various types like linear trend, step function and ramp. According to the discrepancy of variation characteristics for monitoring data at each well in the same region, periodical analysis of monitoring data is essentially required.

• Clinical and Experimental Pediatrics
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• v.52 no.1
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• pp.99-104
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• 2009

Purpose : Magnetic resonance diffusion tensor imaging-based three-dimensional fiber tractography (DTI-FT) is a new method which demonstrates the orientation and integrity of white matter fibers in vivo. However, clinical application on children with cerebral palsy is still under investigation. We present various abnormal patterns of DTI-FT findings and accordance rate with clinical findings in children with hemiplegic cerebral palsy, to recognize the use fulness of DTI-FT. Methods : The thirteen children with hemiplegic cerebral palsy evaluated at Yeungnam University hospital from March, 2003 to August, 2007 were enrolled in this study and underwent magnetic resonance DTI-FT of the corticospinal tracts. Two regions of interest (ROI) were applied and the termination criteria were fractional anisotropy ${\geq}0.3$, angle ${\leq}70^{\circ}$. Results : The patterns and distribution of abnormal DTI-based corticospinal tractographic findings were interruption(10 cases, 76.9%), reduction of fiber volume (8 cases, 61.5%), agenesis of corticospinal tract (3 cases, 23.1%), transcallosal fiber (2 cases, 15.4%) and, aberrant corticospinal tracts (4 cases, 30.8%). Abnormal DTI-based corticospinal tractographic findings were in accordance with the clinical findings of cerebral palsy in 84.6% of the enrolled patients. Conclusion : Our results suggest that DTI-FT would be a use ful modality in the assessment of the corticospinal tract abnormalities in children with hemiplegic cerebral palsy.

• The Korean Journal of Nuclear Medicine
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• v.34 no.3
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• pp.169-182
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• 2000

Purpose: To investigate the various ictal perfusion patterns and find the relationships between clinical factors and different perfusion patterns. Materials and Methods: Interictal and ictal SPECT and SPECT subtraction were performed in 61 patients with partial epilepsy. Both positive images showing ictal hyperperfusion and negative images revealing ictal hypoperfusion were obtained by SPECT subtraction The ictal perfusion patterns of subtracted SPECT were classified into focal hyperperfusion, hyperperfusion-plus, combined hyperperfusion-hypoperfusion, and focal hypoperfusion only. Results: The concordance rates with epileptic focus were 91.8% in combined analysis of ictal hyperperfusion and hypoperfusion images of subtracted SPECT, 85.2% in hyperperfusion images only of subtracted SPECT, and 68.9% in conventional ictal SPECT analysis. Ictal hypoperfusion occurred less frequently in temporal lobe epilepsy (TLE) than extratemporal lobe epilepsy. Mesial temporal hyperperfusion alone was seen only in mesial TLE while lateral temporal hyperperfusion alone was observed only in neocortical TLE. Hippocampal sclerosis had much lower incidence of ictal hypoperfusion than any other pathology. Some patients showed ictal hypoperfusion at epileptic focus with ictal hyperperfusion in the neighboring brain regions where ictal discharges propagated. Conclusion: Hypoperfusion as well as hyperperfusion in ictal SPECT should be considered for localizing epileptic focus. Although the mechanism of ictal hypoperfusion could be an intra-ictal early exhaustion of seizure focus or a steal phenomenon by the propagation of ictal discharges to adjacent brain areas, further study is needed to elucidate it.

• The Korean Journal of Nuclear Medicine
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• v.32 no.1
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• pp.32-49
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• 1998

For estimation of regional myocardial blood flow with O-15 water PET, a few modifications considering partial volume effect based on single compartment model have been proposed. In this study, we attempted to quantify the degree of heterogeneity and to show the effect of tissue flow heterogeneity on partition coefficient(${\lambda}$) and to find the relation between perfusable tissue index(PTI) and ${\lambda}$ by computer simulation using two modified models. We simulated tissue curves for the regions with homogeneous and heterogeneous blood flow over a various flow range(0.2-4.0ml/g/min). Simulated heterogeneous tissue composed of 4 subregions of the same or different size of block which have different homogeneous flow and different degree of slope of distribution of blood flow. We measured the index representing heterogeneity of distribution of blood flow for each heterogeneous tissue by the constitution heterogeneity(CH). For model I, we assumed that tissue recovery coefficient ($F_{MME}$) was the product of partial volume effect($F_{MMF}$) and PTI. Using model I, PTI, flow, and $F_{MM}$ were estimated. For model II, we assumed that partition coefficient was another variable which could represent tissue characteristics of heterogeneity of flow distribution. Using model II, PTI, flow and ${\lambda}$ were estimated. For the simulated tissue with homogeneous flow, both models gave exactly the same estimates, of three parameters. For the simulated tissue with heterogeneous flow distribution, in model I, flow and $F_{MM}$ were correctly estimated as CH was increased moderately. In model II, flow and ${\lambda}$ were decreased curvi-linearly as CH was increased. The degree of underestimation of ${\lambda}$ obtained using model II, was correlated with CH. The degree of underestimation of flow was dependent on the degree of underestimation of ${\lambda}$. PTI was somewhat overestimated and did not change according to CH. We conclude that estimated ${\lambda}$ reflect the degree of tissue heterogeneity of flow distribution. We could use the degree of underestimation of ${\lambda}$ to find the characteristic heterogeneity of tissue flow and use ${\lambda}$ to recover the underestimated flow.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.801-810
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• 2008

The principal objective of this study was to assess Korea's traditional ritual food culture, and to compare two types of ancestral rites the Hyang-Sa and Bool-cheon-wi rites which were held in the Daegu and Andong regions of Korea. In this study, we describe the performance of the Bool-cheon-wi rites held by two head families located near the Andong area namely, the head family of Seoae Ryu Seong-Ryong(1542-1607)(Seoae) who was well-respected for his writings and personality, and the head family of Dangye Ha Wee-Ji(1412-1456)(Dangye) who was well-known and famous as one of the members of the Sa-ryuk-sin. This research was conducted via diredt engagement in these memorial services and several interviews with the families. The results were summarized as follows; Foods used in the Hyang-sa rites including Mae(bap), Kook, Jaban(Jogee), Po(dried fish), Juck, boiled and seasoned vegetables, fruits, confections, and liquor. Jobap and Ssalbap were used as Mae at SD(Seo Dalsung), and PMPH(Pahoi Myogul Habin Park) used Jo, Hyunmy, Pi and Susu in the raw. The dishes on the table were arranged as follows. A wine cup was placed in the first row, Po(a dried pollack), and jujube and nuts in the second row, Ryukpo(slices of dried beef), Sangeogogi were set at the third row, and Soegogi, pork, Mu, and Minary were placed in the fourth row, and the head of the pig was placed in the center of the table at SD. A wine cup, Soegogi, and pork were positioned in the first row, Mu, Minary, Pi and Susu were placed in the second row, and Jogee, Jo, and Hyunmy were placed in the third row at PMPH. The sacrificial foods offered for Bool-cheon-wi rites were as follows; Mae(bap) Kook noodle Jogee Tang(stew) Po Juck Tucks boiled, seasoned and salted vegetables Jeon fruit confectioneries liquor(chungju). The head family of Seoae Yu Seong-Ryong utilized 5 types of Tang(meat stew, fish stew, chicken stew, vegetable stew, seafood stew), whereas the head family of Dangye Ha Wee-Ji utilized 3 kinds of Tang(meat stew, fish stew, vegetable stew). As a basic Tuck, Shi-roo-tuck(a steamed rice cake), piled up to 25 layers, was primarily utilized. In particular, Jung-Gae(Seoae's favorite food) was placed on the table. For grilled-meat food(Juck), Yu's family used raw meat and Ha's family the half-cooked meat. The main types of Jucks used were meat-Juck, fish-Juck, chicken-Juck, and these were not served one by one. Hyang-sa and Bool-cheon-wi rites have an the educational function, in that they allow for the carrying out of filial duties by a heartfelt performance of performing the ceremony, by taking great care from the pre-rite preparations to the post-rite period. In addition, these rites have various meanings, as events that strengthen the ties of blood relations of ancestors and themselves, and to promote and harmonize family friendships, they may also have religious meaning in the culture, as prayers are offered that all the family's descendants may be blessed, live long and enjoy abundance whlie respecting their ancestors. As for the role of Hyang-sa and Bool-cheon-wi rites in today's nuclear family society, it can be said that these rites remain especially important as a method to strengthen community consciousness by fostering an understanding of the meaning of existence itself, and thus inspiring the roots of consciousness.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.2
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• pp.183-196
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• 2003

Objectives：The Purpose of this study is to investigate the reliability and validity of Korean Parent and Teacher Conners' Rating Scale. Methods：Randomly selected 1st to 6th graders of the two elementary schools(N=1044) in Anyang City participated in the study. Children diagnosed with ADHD(N=23) at the child and adolescent clinic at a university affiliated hospital were included in the study for the analysis of clinical validity of the scales. Parent and teacher completed Korean Conners' Rating Scale and Korean-ADHD Rating Scale(KARS). In addition, parents completed Korean-Children Behavior CheckList(K-CBCL). Descriptive statistics, t-test, and analysis of variance were performed. Results：Scores of Korean Conners' Parents Rating Scale were significantly correlated with those of Korean Conners Teacher Rating Scale. High internal consistency reliability were demonstrated in both parent and teacher rating scales. There were significant correlations among sub-scales of Conners' Rating Scales, K-CBCL and K-ARS. Factor analyses revealed that the K-CTRS had three-factor structure (Inattention-Passivity, Hyperactivity, Conduct Problem) and the K-CPRS had five-factor structure(Impulsive-Hyperactive, Conduct Problem I, Anxiety, Psychosomatic, Conduct Problem II). Conners' Rating Scales effectively distinguish children with ADHD from children without ADHD. Conclusion：Korean Parent and Teacher Conners' Rating Scales are valid and reliable instruments that are useful for screening and identifying childhood problem behaviors. Future studies are required with a larger number of sample sizes including adolescents from various geographic regions.

• Korean Journal of Environmental Agriculture
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• v.33 no.2
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• pp.86-102
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• 2014

BACKGROUND: According to the types of human interference, there are various plants that have strong vitality and ability to breed in the dry field. Recently, climate change alters the geographical distribution and phenology of the plant species. So, we need to understand present occurrence pattern and ecological characteristics of these plants. METHODS AND RESULTS: The plant species data were obtained from 8 regions in Jeolla-do. Flora investigation was done from May 2013 to September 2013. Habitat type of dry field in Jeolla-do was classified into 3 types (inside of dry field: IDF, embankment around the end of a dry field: EDF, levee slope of dry field: LS). The vascular plants of study area were listed 296 taxa which contain 68 families, 203 genera, 244 species, 43 varieties and 9 forms. The vascular plants of three different habitat types were IDF 174 taxa, EDF 249 taxa and LS 136 taxa. The occurrence rate of Therophyte was arranged by the order of IDF(67.6%), EDF(51.9%), LS(54.3%). Naturalized rate was analysed as IDF 27.9%, EDF 21.0%, LS 18.6%. Urbanization index was analysed as IDF 11.8%, EDF 13.7%, LS 10.0%. CONCLUSION: With these results, we found that three habitat types were ecological difference affected by the human impacts. Also, we found environmental indicators through the ecological characteristics of flora for the type of habitat of dry field. These indicators will help assess the agriculture environmental variability and the floral change according to the climate change in dry field.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.1
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• pp.53-64
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• 2008

Statement of problem: Peri-implant marginal bone loss is an important factor that affects the success of implants in esthetics and function. Various efforts have been made to reduce this bone loss by improving implant design and surface texture. Previous studies have shown that early marginal bone loss is affected by implant neck designs. Purpose: The purpose of this study was to examine the influence of laser microtexturing of implant collar on peri-implant marginal bone loss. Materials and methods: Radiographical marginal bone loss was examined in patients treated with implant-supported fixed partial dentures. Marginal bone level was examined with 101 implant fixtures installed in 53 patients at three periods(at the time of implantation, prosthetic treatment and 6-month after loading). Four types of implants were examined. The differences of bone loss between implants(ITI standard) with enough biologic width and implants(ITI esthetic plus, Silhouette IC, Silhouette IC Laser-$Lok^{TM}$) with insufficient biologic width have been compared. Resorption angles were examined at the time of prosthetic delivery and 6-month after loading. Results and Conclusion: Within the limitation of this study, the following results were drawn. 1. The marginal bone loss of ITI standard and Silhouette IC Laser-$Lok^{TM}$ was less than that of ITI esthetic plus and Silhouette IC(P<0.05). The marginal bone loss between ITI standard and Silhouette IC Laser-$Lok^{TM}$ had no significant statistical difference(P>0.05). There was no significant statistical difference between marginal bone loss of ITI esthetic plus and Silhouette IC(P>0.05). 2. There was no significant difference in marginal bone loss between maxilla and mandible(P>0.05). 3. There was no significant difference in resorption angle among four types of implants(P>0.05). The marginal bone of implants with supracrestal collar design of less than that of biologic width had resorbed more than those with sufficient collar length. The roughness and laser microtexturing of implant neck seem to affect these results. If an implant with collar length of biologic width, exposure of fixture is a possible complication especially in the anterior regions of dentition that demand high esthetics. Short smooth neck implant are often recommended in these areas which may lack the distance between microgap and the marginal bone level. In these cases, the preservation of marginal bone must be put into consideration. From the result of this study, it may be concluded that laser microtexturing of implant neck is helpful in the preservation of marginal bone.