• Journal of Korean Society of Forest Science
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• v.38 no.1
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• pp.33-45
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• 1978

The purpose of present study is to analyze the genetic variation of natural stand of Pinus densiflora. In 1975 following after the selection of 1974, twenty trees from each of three natural populations of the species were selected and their open-pollinated seeds were collected, and the locations and conditions of the populations ate presented in table 1, 2 and figure 1. Some morphological traits of the populations were already detailed in our second report of this series, in which Myong-Ju and Ul-Jin populations were regarded to be superior phenotypically to suweon population. The morphological traits of cone, seed and seed-wing, and also the growth performances and needle characters of the seedling were observed in the present study according to the previous methods. The results obtained are summarized as follows; 1. The meteorological data obtained by averaging the records of 30 year period (1931~1960) measured from the nearest meteorological stations to each population are shown in fig.2, 3, 4. The distributional patterns of investigated climate factors are generally considered to be similar among the locations. However, the precipitation density during growing season and the air temperature during dormant season on Suweon area, population 6, were quite different from those of the other areas. 2. The measurements of fresh cone weight, length, diameter and cone index, i.e., length to diameter ratio are presented in table 7. As shown in table 7, all these traits except for cone diameter seem to be highly significant in population differences and family differences within population. 3. The morphological traits of seed and seed-wing are detailed in table 8, 9, and highly significant differences are recognized among the populations and the families within population in seed-wing length, seed-wing index, seed weight, seed-length and seed index but not among the populations in the other observed traits. The values of correlation coefficient between the characters of cone and seed are given in table 10 and the positive significant correlations can be observed in the most parts of the compared traits. 4. Significant statistical differences among populations and families within population are observed in the growth performances of 1-0 and 1-1 seedling height of these progenies. But the differences in root collar diameter are shown only among families within population. As shown in table 13, the most parts of correlations are not significant statistically between the growth performances of seedling and the seed characters. 5. The number of stomata row on both sides of needle and the serration density were measured in the seedlings from each of the families of the three populations. As shown in table 15, statistical differences are considered to be significant among the populations and among the families within population in serration density but not among the populations in stomata row on both sides of the needle. The results differ from those of the third report of this series. Even if one of the reason seems to be the diversity of selected populations, it could not be confirmed definitely. The correlations between progenies and parents are not generally observed in the investigated traits of needle as shown in table 16.

• Journal of Global Scholars of Marketing Science
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• v.17 no.2
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• pp.55-73
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• 2007

Festivals are an indispensable feature of cultural tourism(Formica & Uysal, 1998). Cultural tourism festivals are increasingly being used as instruments promoting tourism and boosting the regional economy. So much research related to festivals is undertaken from a variety of perspectives. Plans to revisit a particular festival have been viewed as an important research topic both in academia and the tourism industry. Therefore festivals have frequently been leveled as cultural events. Cultural tourism festivals have become a crucial component in constituting the attractiveness of tourism destinations(Prentice, 2001). As a result, a considerable number of tourist studies have been carried out in diverse cultural tourism festivals(Backman et al., 1995; Crompton & Mckay, 1997; Park, 1998; Clawson & Knetch, 1996). Much of previous literature empirically shows the close linkage between tourist satisfaction and behavioral intention in festivals. The main objective of this study is to investigate the effects of evaluation attributes of cultural tourism festivals on satisfaction and behavioral intention. accomplish the research objective, to find out evaluation items of cultural tourism festivals through the literature study an empirical study. Using a varimax rotation with Kaiser normalization, the research obtained four factors in the 18 evaluation attributes of cultural tourism festivals. Some empirical studies have examined the relationship between behavioral intention and actual behavior. To understand between tourist satisfaction and behavioral intention, this study suggests five hypotheses and hypothesized model. In this study, the analysis is based on primary data collected from visitors who participated in '2006 Gwangju Kimchi Festival'. In total, 700 self-administered questionnaires were distributed and 561 usable questionnaires were obtained. Respondents were presented with the 18 satisfactions item on a scale from 1(strongly disagree) to 7(strongly agree). Dimensionality and stability of the scale were evaluated by a factor analysis with varimax rotation. Four factors emerged with eigenvalues greater than 1, which explained 66.40% of the total variance and Cronbach' alpha raging from 0.876 to 0.774. And four factors named: advertisement and guides, programs, food and souvenirs, and convenient facilities. To test and estimate the hypothesized model, a two-step approach with an initial measurement model and a subsequent structural model for Structural Equation Modeling was used. The AMOS 4.0 analysis package was used to conduct the analysis. In estimating the model, the maximum likelihood procedure was used.In this study Chi-square test is used, which is the most common model goodness-of-fit test. In addition, considering the literature about the Structural Equation Modeling, this study used, besides Chi-square test, more model fit indexes to determine the tangibility of the suggested model: goodness-of-fit index(GFI) and root mean square error of approximation(RMSEA) as absolute fit indexes; normed-fit index(NFI) and non-normed-fit index(NNFI) as incremental fit indexes. The results of T-test and ANOVAs revealed significant differences(0.05 level), therefore H1(Tourist Satisfaction level should be different from Demographic traits) are supported. According to the multiple Regressions analysis and AMOS, H2(Tourist Satisfaction positively influences on revisit intention), H3(Tourist Satisfaction positively influences on word of mouth), H4(Evaluation Attributes of cultural tourism festivals influences on Tourist Satisfaction), and H5(Tourist Satisfaction positively influences on Behavioral Intention) are also supported. As the conclusion of this study are as following: First, there were differences in satisfaction levels in accordance with the demographic information of visitors. Not all visitors had the same degree of satisfaction with their cultural tourism festival experience. Therefore it is necessary to understand the satisfaction of tourists if the experiences that are provided are to meet their expectations. So, in making festival plans, the organizer should consider the demographic variables in explaining and segmenting visitors to cultural tourism festival. Second, satisfaction with attributes of evaluation cultural tourism festivals had a significant direct impact on visitors' intention to revisit such festivals and the word of mouth publicity they shared. The results indicated that visitor satisfaction is a significant antecedent of their intention to revisit such festivals. Festival organizers should strive to forge long-term relationships with the visitors. In addition, it is also necessary to understand how the intention to revisit a festival changes over time and identify the critical satisfaction factors. Third, it is confirmed that behavioral intention was enhanced by satisfaction. The strong link between satisfaction and behavioral intentions of visitors areensured by high quality advertisement and guides, programs, food and souvenirs, and convenient facilities. Thus, examining revisit intention from a time viewpoint may be of a great significance for both practical and theoretical reasons. Additionally, festival organizers should give special attention to visitor satisfaction, as satisfied visitors are more likely to return sooner. The findings of this research have several practical implications for the festivals managers. The promotion of cultural festivals should be based on the understanding of tourist satisfaction for the long- term success of tourism. And this study can help managers carry out this task in a more informed and strategic manner by examining the effects of demographic traits on the level of tourist satisfaction and the behavioral intention. In other words, differentiated marketing strategies should be stressed and executed by relevant parties. The limitations of this study are as follows; the results of this study cannot be generalized to other cultural tourism festivals because we have not explored the many different kinds of festivals. A future study should be a comparative analysis of other festivals of different visitor segments. Also, further efforts should be directed toward developing more comprehensive temporal models that can explain behavioral intentions of tourists.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.125-136
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• 2008

Statement of problem: Since the concept of osseointegration in dental implants was introduced by $Br{{\aa}}nemark$ et al, high long-term success rates have been achieved. Though the use of dental implants have increased dramatically, there are few studies on domestic implants with clinical and objective long-term data. Purpose: The aim of this retrospective study was to provide long-term data on the $Neoplan^{(R)}$ implant, which features a sandblasted and acid-etched surface and external connection. Material and methods: 96 $Neoplan^{(R)}$ implants placed in 25 patients in Yonsei University Hospital were examined to determine the effect of the factors on marginal bone loss, through clinical and radiographic results during 18 to 57 month period. Results: 1. Out of a total of 96 implants placed in 25 patients, two fixtures were lost, resulting in 97.9% of cumulative survival rate. 2. Throughout the study period, the survival rates were 96.8% in the maxilla and 98.5% in the mandible. The survival rates were 97.6% in the posterior regions and 100% in the anterior regions. 3. The mean bone loss for the first year after prosthesis placement and the mean annual bone loss after the first year for men were significantly higher than that of women (P<0.05). 4. The group of partial edentulism with no posterior teeth distal to the implant prosthesis showed significantly more bone loss compared to the group of partial edentulism with presence of posterior teeth distal to the implant prosthesis in terms of mean bone loss for the first year and after the first year (P<0.05). 5. The mean annual bone loss after the first year was more pronounced in posterior regions compared to anterior regions (P<0.05). 6. No significant difference in marginal bone loss was found in the following factors: jaws, type of prostheses, type of opposing dentition, and submerged /non-submerged implants (P<0.05). Conclusion: On the basis of these results, the factors influencing marginal bone loss were gender, type of edentulism, and location in the arch, while the factors such as arch, type of prostheses, type of opposing dentition, submerged / non- submerged implants had no significant effect on bone loss. In the present study, the cumulative survival rate of the $Neoplan^{(R)}$ implant with a sandblasted and acid-etched surface was 97.9% up to a maximum 57-month period. Further long-term investigations for this type of implant system and evaluation of other various domestic implant systems are needed in future studies.

• The Korean Journal of Quaternary Research
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• v.20 no.1 s.26
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• pp.51-66
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• 2006

The climate of the last glacial maximum (LGM) in northeast Asia is simulated with an atmospheric general circulation model of NCAR CCM3 at spectral truncation of T170, corresponding to a grid cell size of roughly 75 km. Modern climate is simulated by a prescribed sea surface temperature and sea ice provided from NCAR, and contemporary atmospheric CO2, topography, and orbital parameters, while LGM simulation was forced with the reconstructed CLIMAP sea surface temperatures, sea ice distribution, ice sheet topography, reduced $CO_2$, and orbital parameters. Under LGM conditions, surface temperature is markedly reduced in winter by more than $18^{\circ}C$ in the Korean west sea and continental margin of the Korean east sea, where the ocean exposed to land in the LGM, whereas in these areas surface temperature is warmer than present in summer by up to $2^{\circ}C$. This is due to the difference in heat capacity between ocean and land. Overall, in the LGM surface is cooled by $4{\sim}6^{\circ}C$ in northeast Asia land and by $7.1^{\circ}C$ in the entire area. An analysis of surface heat fluxes show that the surface cooling is due to the increase in outgoing longwave radiation associated with the reduced $CO_2$ concentration. The reduction in surface temperature leads to a weakening of the hydrological cycle. In winter, precipitation decreases largely in the southeastern part of Asia by about $1{\sim}4\;mm/day$, while in summer a larger reduction is found over China. Overall, annual-mean precipitation decreases by about 50% in the LGM. In northeast Asia, evaporation is also overall reduced in the LGM, but the reduction of precipitation is larger, eventually leading to a drier climate. The drier LGM climate simulated in this study is consistent with proxy evidence compiled in other areas. Overall, the high-resolution model captures the climate features reasonably well under global domain.

• Parasites, Hosts and Diseases
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• v.29 no.3
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• pp.235-244
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• 1991

An epidemiological study and mass treatments of Enterobius vermicularis infection among children near Wonju area of Kangwon province were carried out. The children were divided into 4 groups according to their residing localities; children in the mountainous area, rural area, urban area and in orphanage. They were examined by adhesive cellotape anal swab technique, and egg positive rates were obtained. The rates of egg reduction and re-infection rates after repeated mass treatments were also observed. The results obtained were as follows: 1. The overall egg Positive rate of E. vermicularis in the first screening was 19.9% (251 out of 1, 262 examinees; 19.7% in males and 20.1% in females). The positive rates were 13.0% in the mountainous area, 11 9% in the rural area, 15.1% in the urban (medium-sized) area and 61.9% in orphanages. 2. The highest positive rates were observed in the kindergarten children, and 1st and 2nd grade children of primary schools (26.2~32.2%), and the lowest rate (13.6%) in 6-year grade children of primary schools. 3. Cumulative detection rates from 3 repeated anal swabs at 4~5 days interval were higher (70.8%) than those from single anal swabs (50.0~59.2%). 4. Out of the examinees who showed the highest cumulative positive rate (70.8%), about 39.2% were consecutively positive in 3 anal swabs. Among different groups of children, the higher the total egg detection rates (87.5%), the higher the consecutive positive rates (71.9%) . 5. A total of 2, 609 (male : female=1 : 12.4) worms were collected from 17 egg-positive cases treated with anthelinintics. The mean number of worms per child was 153 (range: 4-824) . 6. The egg-positive cases in several studied groups (180 children) were treated with anthelmintics 6 times at 3-week intervals. In this case, the overall positive rate was decreased from 54.8% to 2.2% at 15 weeks after the treatments, but no complete negative conversion was experienced. However, in a group of children (154 children) including egg Positive and negative cases who were both treated with anthelmintics at 3-week interval, a complete egg-negative conversion was observed in the 9th week after treatments. 7. The egg-detection rate in the brothers or sisters of egg Positive children was 70.0% (28 out of 40 examined), and the egg-positive rate according to the family unit was 69.7%. In summarizing the above results, it is concluded that Enterobius vermicularis infection is still highly prevalent among children in Korea, and that repeated mass treatments of more than 3 times will be effective for control of this infection.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.2
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• pp.271-288
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• 2002

Authors investigated the pathogenesis and treatment of dennatosurgical diseases in the ImJeungJiNamUiAn(臨證指南醫案). 1. The symptoms and diseases of dermatosurgery were as follows; 1) BanSaJinRa(반사진라) : eczema, atopic dermatitis, seborrheic dermatitis, psoriasis, lichen planus, pityriasis rosea, hives, dermographism, angioedema, cholinergic urticaria, urticaria pigmentosa, acne, milium, syringoma, keratosis pilaris, discoid lupus erythematosus, hypersensitivity vasculitis, drug eruption, polymorphic light eruption, rheumatic fever, juvenile rheumatoid arthritis(Still's disease), acute febrile neutrophilic dermatosis(Sweet's syndrome), Paget's disease, folliculitis, viral exanthems, molluscum contagiosum, tinea, tinea versicolor, lymphoma, lymphadenitis, lymphangitis, granuloma annulare, cherry angioma 2) ChangYang(瘡瘍) : acute stage eczema, seborrheic dermatitis, stasis ulcer, intertrigo, xerosis, psoriasis, lichen planus, ichthyosis, pityriasis rosea, rosacea, acne, keratosis pilaris, dyshidrosis, dermatitis herpetiformis, herpes gestationis, bullae in diabetics, pemphigus, lupus erythematosus, fixed drug eruption, erythema multiforme, toxic epidermal necrolysis, toxic shock syndrome, staphylococcal scaled skin syndrome, scarlet fever, folliculitis, impetigo, pyoderma gangrenosum, tinea, candidiasis, scabies, herpes simplex, herpes zoster, chicken pox, Kawasaki syndrome, lipoma, goiter, thyroid nodule, thyroiditis, hyperthyroidism, thyroid cancer, benign breast disorder, breast carcinoma, hepatic abscess, appendicitis, hemorrhoid 3) Yeok(疫) : scarlet fever, chicken pox, measles, rubella, exanthem subitum, erythema infectiosum, Epstein-Barr virus infection, cytomegalovirus infection, hand-foot-mouth disease, Kawasaki disease 4) Han(汗) : hyperhidrosis 2. The pathogenesis and treatment of dermatosurgery were as follows; 1) When the pathogenesis of BalSa(발사), BalJin(發疹), BalLa(발라) and HangJong(項腫) are wind-warm(風溫), exogenous cold with endogenous heat(外寒內熱), wind-damp(風濕), the treatment of evaporation(解表) with Menthae Herba(薄荷), Arctii Fructus(牛蒡子), Forsythiae Fructus(連翹) Mori Cortex(桑白皮), Fritillariae Cirrhosae Bulbus(貝母), Armeniaoae Amarum Semen(杏仁), Ephedrae Herba(麻黃), Cinnamomi Ramulus(桂枝), Curcumae Longae Rhizoma(薑黃), etc can be applied. 2) When the pathogenesis of BuYang(부양), ChangI(瘡痍) and ChangJilGaeSeon(瘡疾疥癬) are wind-heat(風熱), blood fever with wind transformation(血熱風動), wind-damp(風濕), the treatment of wind-dispelling(疏風) with Arctii Fructus(牛蒡子), Schizonepetae Herba(荊芥), Ledebouriellae Radix(防風), Dictamni Radicis Cortex(白鮮皮), Bombyx Batrytioatus(白？?), etc can be applied. 3) When the pathogenesis of SaHuHaeSu(사후해수), SaJin(사진), BalJin(發疹), EunJin(은진) and BuYang(부양) are wind-heat(風熱), exogenous cold with endogenous heat(外寒內熱), exogenous warm pathogen with endogenous damp-heat(溫邪外感 濕熱內蘊), warm pathogen's penetration(溫邪內陷), insidious heat's penetration of pericardium(伏熱入包絡), the treatment of Ki-cooling(淸氣) with TongSeongHwan(通聖丸), Praeparatum(豆？), Phyllostachys Folium(竹葉), Mori Cortex(桑白皮), Tetrapanacis Medulla(通草), etc can be applied. 4) When the pathogenesis of JeokBan(적반), BalLa(발라), GuChang(久瘡), GyeolHaek(結核), DamHaek(痰核), Yeong(？), YuJu(流注), Breast Diseases(乳房疾患) and DoHan(盜汗) are stagnancy's injury of Ki and blood(鬱傷氣血), gallbladder fire with stomach damp(膽火胃濕), deficiency of Yin in stomach with Kwolum's check (胃陰虛 厥陰乘), heat's penetration of blood collaterals with disharmony of liver and stomach(熱入血絡 肝胃不和), insidious pathogen in Kwolum(邪伏厥陰), the treatment of mediation(和解) with Prunellae Spica(夏枯草), Chrysanthemi Flos(菊花), Mori Folium (桑葉), Bupleuri Radix(柴胡), Coptidis Rhizoma(黃連), Scutellariae Radix(黃芩), Gardeniae Fructus(梔子), Cyperi Rhizoma(香附子), Toosendan Fructus(川？子), Curcumae Radix(鬱金), Moutan Cortex(牧丹皮), Paeoniae Radix Rubra(赤芍藥), Unoariae Ramulus Et Uncus(釣鉤藤), Cinnamorni Ramulus(桂枝), Paeoniae Radix Alba(白芍藥), Polygoni Multiflori Radix (何首烏), Cannabis Fructus (胡麻子), Ostreae Concha(牡蠣), Zizyphi Spinosae Semen(酸棗仁), Pinelliae Rhizoma(半夏), Poria(백복령). etc can be applied. 5) When the pathogenesis of BanJin(반진), BalLa(발라), ChangI(瘡痍), NamgChang(膿瘡). ChangJilGaeSeon(瘡疾疥癬), ChangYang(瘡瘍), SeoYang(署瘍), NongYang(膿瘍) and GweYang(潰瘍) are wind-damp(風濕), summer heat-damp(暑濕), damp-warm(濕溫), downward flow of damp-heat(濕熱下垂), damp-heat with phlegm transformation(濕熱化痰), gallbladder fire with stomach damp(膽火胃濕), overdose of cold herbs(寒凉之樂 過服), the treatment of damp-resolving(化濕) with Pinelliae Rhizoma(半夏), armeniacae Amarum Semen(杏仁), Arecae Pericarpium(大腹皮), Poria(백복령), Coicis Semen(薏苡仁), Talcum(滑石), Glauberitum(寒水石), Dioscoreae Tokoro Rhizoma(？？), Alismatis Rhizoma(澤瀉), Phellodendri Cortex(黃柏), Phaseoli Radiati Semen(？豆皮), Bombycis Excrementum(?沙), Bombyx Batryticatus(白？?), Stephaniae Tetrandrae Radix(防己), etc can be applied. 6) When the pathogenesis of ChangPo(瘡泡), hepatic abscess(肝癰) and appendicitis(腸癰) are food poisoning(食物中毒), Ki obstruction & blood stasis in the interior(기비혈어재과), damp-heat stagnation with six Bu organs suspension(濕熱結聚 六腑不通), the treatment of purgation(通下) with DaeHwangMokDanPiTang(大黃牧丹皮湯), Manitis Squama(穿山甲), Curcumae Radix(鬱金), Curcumae Longae Rhizoma(薑黃), Tetrapanacis Medulla(通草), etc can be applied. 7) When the pathogenesis of JeokBan(적반), BanJin(반진), EunJin(은진). BuYang(부양), ChangI(瘡痍), ChangPo(瘡泡), GuChang(久瘡), NongYang(膿瘍), GweYang(潰瘍), Jeong(정), Jeol(癤), YeokRyeo(疫？) and YeokRyeolpDan(疫？入？) are wind-heat stagnation(風熱久未解), blood fever in Yangmyong(陽明血熱), blood fever with transformation(血熱風動), heat's penetration of blood collaterals(熱入血絡). fever in blood(血分有熱), insidious heat in triple energizer(三焦伏熱), pathogen's penetration of pericardium(心包受邪), deficiency of Yong(營虛), epidemic pathogen(感受穢濁), the treatment of Yong & blood-cooling(淸營凉血) with SeoGakJiHwangTang(犀角地黃湯), Scrophulariae Radix(玄參), Salviae Miltiorrhizae Radix(丹參), Angelicae Gigantis Radix(當歸), Polygoni Multiflori Radix(何首烏), Cannabis Fructus(胡麻子), Biotae Semen(柏子仁), Liriopis Tuber(麥門冬), Phaseoli Semen(赤豆皮), Forsythiae Fructus(連翹), SaJin(사진), YangDok(瘍毒) and YeokRyeoIpDan(역려입단) are insidious heat's penetration of pericardium(伏熱入包絡), damp-warm's penetration of blood collaterals(濕溫入血絡), epidemic pathogen's penetration of pericardium(심포감수역려), the treatment of resuscitation(開竅) with JiBoDan(至寶丹), UHwangHwan(牛黃丸), Forsythiae Fructus(連翹), Curcumae Radix(鬱金), Tetrapanacis Medulla(通草), Acori Graminei Rhizoma(石菖蒲), etc can be applied. 9) When the pathogenesis of SaHuSinTong(사후신통), SaHuYeolBuJi(사후열부지), ChangI(瘡痍), YangSon(瘍損) and DoHan(盜汗) are deficiency of Yin in Yangmyong stomach(陽明胃陰虛), deficiency of Yin(陰虛), the treatment of Yin-replenishing(滋陰) with MaekMunDongTang(麥門冬湯), GyeongOkGo(瓊玉膏), Schizandrae Fructus(五味子), Adenophorae Radix(沙參), Lycii Radicis Cortex (地骨皮), Polygonati Odorati Rhizoma(玉竹), Dindrobii Herba(石斛), Paeoniae Radix Alba(白芍藥), Ligustri Lucidi Fructus (女貞子), etc can be applied. 10) When the pathogenesis of RuYang(漏瘍) is endogenous wind in Yang collaterals(陽絡內風), the treatment of endogenous wind-calming(息風) with Mume Fructus(烏梅), Paeoniae Radix Alba (白芍藥), etc be applied. 11) When the pathogenesis of GuChang(久瘡), GweYang(潰瘍), RuYang(漏瘍), ChiChang(痔瘡), JaHan(自汗) and OSimHan(五心汗) are consumption of stomach(胃損), consumption of Ki & blood(氣血耗盡), overexertion of heart vitality(勞傷心神), deficiency of Yong(營虛), deficiency of Wi(衛虛), deficiency of Yang(陽虛), the treatment of Yang-restoring & exhaustion-arresting(回陽固脫) with RijungTang(理中湯), jinMuTang(眞武湯), SaengMaekSaGunjaTang(生脈四君子湯), Astragali Radix (황기), Ledebouriellae Radix(防風), Cinnamomi Ramulus(桂枝), Angelicae Gigantis Radix(當歸), Ostreae Concha(牡蠣), Zanthoxyli Fructus(川椒), Cuscutae Semen(兎絲子), etc can be applied.

• Journal of the Korean Geotechnical Society
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• v.35 no.5
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• pp.5-19
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• 2019

Considering the natural phenomenon in which steep slopes ($65^{\circ}{\sim}85^{\circ}$) consisting of rock mass remain stable for decades, slopes steeper than 1:0.5 (the standard of slope angle for blast rock) may be applied in geotechnical conditions which are similar to those above at the design and initial construction stages. In the process of analysing the stability of a good to fair continuum rock slope that can be designed as a steep slope, a general method of estimating rock mass strength properties from design practice perspective was required. Practical and genealized engineering methods of determining the properties of a rock mass are important for a good continuum rock slope that can be designed as a steep slope. The Genealized Hoek-Brown (H-B) failure criterion and GSI (Geological Strength Index), which were revised and supplemented by Hoek et al. (2002), were assessed as rock mass characterization systems fully taking into account the effects of discontinuities, and were widely utilized as a method for calculating equivalent Mohr-Coulomb shear strength (balancing the areas) according to stress changes. The concept of calculating equivalent M-C shear strength according to the change of confining stress range was proposed, and on a slope, the equivalent shear strength changes sensitively with changes in the maximum confining stress (${{\sigma}^{\prime}}_{3max}$ or normal stress), making it difficult to use it in practical design. In this study, the method of estimating the strength properties (an iso-angle division method) that can be applied universally within the maximum confining stress range for a good to fair continuum rock mass slope is proposed by applying the H-B failure criterion. In order to assess the validity and applicability of the proposed method of estimating the shear strength (A), the rock slope, which is a study object, was selected as the type of rock (igneous, metamorphic, sedimentary) on the steep slope near the existing working design site. It is compared and analyzed with the equivalent M-C shear strength (balancing the areas) proposed by Hoek. The equivalent M-C shear strength of the balancing the areas method and iso-angle division method was estimated using the RocLab program (geotechnical properties calculation software based on the H-B failure criterion (2002)) by using the basic data of the laboratory rock triaxial compression test at the existing working design site and the face mapping of discontinuities on the rock slope of study area. The calculated equivalent M-C shear strength of the balancing the areas method was interlinked to show very large or small cohesion and internal friction angles (generally, greater than $45^{\circ}$). The equivalent M-C shear strength of the iso-angle division is in-between the equivalent M-C shear properties of the balancing the areas, and the internal friction angles show a range of $30^{\circ}$ to $42^{\circ}$. We compared and analyzed the shear strength (A) of the iso-angle division method at the study area with the shear strength (B) of the existing working design site with similar or the same grade RMR each other. The application of the proposed iso-angle division method was indirectly evaluated through the results of the stability analysis (limit equilibrium analysis and finite element analysis) applied with these the strength properties. The difference between A and B of the shear strength is about 10%. LEM results (in wet condition) showed that Fs (A) = 14.08~58.22 (average 32.9) and Fs (B) = 18.39~60.04 (average 32.2), which were similar in accordance with the same rock types. As a result of FEM, displacement (A) = 0.13~0.65 mm (average 0.27 mm) and displacement (B) = 0.14~1.07 mm (average 0.37 mm). Using the GSI and Hoek-Brown failure criterion, the significant result could be identified in the application evaluation. Therefore, the strength properties of rock mass estimated by the iso-angle division method could be applied with practical shear strength.

• Journal of Intelligence and Information Systems
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• v.27 no.1
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• pp.83-102
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• 2021

The government recently announced various policies for developing big-data and artificial intelligence fields to provide a great opportunity to the public with respect to disclosure of high-quality data within public institutions. KSURE(Korea Trade Insurance Corporation) is a major public institution for financial policy in Korea, and thus the company is strongly committed to backing export companies with various systems. Nevertheless, there are still fewer cases of realized business model based on big-data analyses. In this situation, this paper aims to develop a new business model which can be applied to an ex-ante prediction for the likelihood of the insurance accident of credit guarantee. We utilize internal data from KSURE which supports export companies in Korea and apply machine learning models. Then, we conduct performance comparison among the predictive models including Logistic Regression, Random Forest, XGBoost, LightGBM, and DNN(Deep Neural Network). For decades, many researchers have tried to find better models which can help to predict bankruptcy since the ex-ante prediction is crucial for corporate managers, investors, creditors, and other stakeholders. The development of the prediction for financial distress or bankruptcy was originated from Smith(1930), Fitzpatrick(1932), or Merwin(1942). One of the most famous models is the Altman's Z-score model(Altman, 1968) which was based on the multiple discriminant analysis. This model is widely used in both research and practice by this time. The author suggests the score model that utilizes five key financial ratios to predict the probability of bankruptcy in the next two years. Ohlson(1980) introduces logit model to complement some limitations of previous models. Furthermore, Elmer and Borowski(1988) develop and examine a rule-based, automated system which conducts the financial analysis of savings and loans. Since the 1980s, researchers in Korea have started to examine analyses on the prediction of financial distress or bankruptcy. Kim(1987) analyzes financial ratios and develops the prediction model. Also, Han et al.(1995, 1996, 1997, 2003, 2005, 2006) construct the prediction model using various techniques including artificial neural network. Yang(1996) introduces multiple discriminant analysis and logit model. Besides, Kim and Kim(2001) utilize artificial neural network techniques for ex-ante prediction of insolvent enterprises. After that, many scholars have been trying to predict financial distress or bankruptcy more precisely based on diverse models such as Random Forest or SVM. One major distinction of our research from the previous research is that we focus on examining the predicted probability of default for each sample case, not only on investigating the classification accuracy of each model for the entire sample. Most predictive models in this paper show that the level of the accuracy of classification is about 70% based on the entire sample. To be specific, LightGBM model shows the highest accuracy of 71.1% and Logit model indicates the lowest accuracy of 69%. However, we confirm that there are open to multiple interpretations. In the context of the business, we have to put more emphasis on efforts to minimize type 2 error which causes more harmful operating losses for the guaranty company. Thus, we also compare the classification accuracy by splitting predicted probability of the default into ten equal intervals. When we examine the classification accuracy for each interval, Logit model has the highest accuracy of 100% for 0~10% of the predicted probability of the default, however, Logit model has a relatively lower accuracy of 61.5% for 90~100% of the predicted probability of the default. On the other hand, Random Forest, XGBoost, LightGBM, and DNN indicate more desirable results since they indicate a higher level of accuracy for both 0~10% and 90~100% of the predicted probability of the default but have a lower level of accuracy around 50% of the predicted probability of the default. When it comes to the distribution of samples for each predicted probability of the default, both LightGBM and XGBoost models have a relatively large number of samples for both 0~10% and 90~100% of the predicted probability of the default. Although Random Forest model has an advantage with regard to the perspective of classification accuracy with small number of cases, LightGBM or XGBoost could become a more desirable model since they classify large number of cases into the two extreme intervals of the predicted probability of the default, even allowing for their relatively low classification accuracy. Considering the importance of type 2 error and total prediction accuracy, XGBoost and DNN show superior performance. Next, Random Forest and LightGBM show good results, but logistic regression shows the worst performance. However, each predictive model has a comparative advantage in terms of various evaluation standards. For instance, Random Forest model shows almost 100% accuracy for samples which are expected to have a high level of the probability of default. Collectively, we can construct more comprehensive ensemble models which contain multiple classification machine learning models and conduct majority voting for maximizing its overall performance.

• Asia Marketing Journal
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• v.14 no.1
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• pp.131-157
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• 2012

Despite the voluminous research on switching barriers, the notion that they can generate negative responses has not been investigated. Further, a critical question is what determines the strength of such negative responses. To address this question, the classic theory of psychological reactance is briefly reviewed, and the idea of switching barrier is advanced. This study attempts to suggest a model on the negative effects of switching- frustrated situation, based on the studies on psychological reactance. According to psychological reactance theory(Brehm 1966), whenever a freedom is threatened or removed, individuals are motivated, at least temporarily, to restore their freedom. For example, if individuals think they are free to engage in behaviors .v, y, or z, then threatening their freedom to engage in x would cause psychological reactance. This reactance could be reduced by an increase in the perceived attractiveness of engaging in, the threatened behavior(Kivetz 2005). This investigation seeks to extend existing switching barrier research in three important ways. First, while the past research has emphasized only positive role of switching barrier, this study address negative role of it by applying psychological reactance theory. Second, to find negative results of switching barrier, I suggest negative psychological response including regret to the past choice, resentment to the present provider, and strong desire to the alternative provider. Third, I suggest the perceived severity of the switching barriers, the attractiveness of the alternative as switching-frustrated situation which can lead to negative results. And, in addition to these relationships, I added moderated effects of perceived justice for better explanation. So this study includes the following hypotheses. H1-1 ~ H1-3: The attractiveness of the alternative has a positive effect regret to the past choice (h1-1), resentment to the present provider (h1-2), and strong desire to the alternative provider (h1-3). H2-1 ~ H2-3 : The perceived severity of the switching barrier has a positive effect regret to the past choice (h2-1), resentment to the present provider (h2-2), and strong desire to the alternative provider (h2-3). H3-1 ~ H3-3 : The positive relationships between the attractiveness of the alternative and consumer' negative responses will be stronger at low level of perceived justice than at high level of perceived justice. H4-1 ~ H4-3 : The positive relationships between the perceived severity of the switching barrier and consumer' negative responses will be stronger at low level of perceived justice than at high level of perceived justice. Survey research is employed to test hypotheses involving perceived severity of the switching barrier(Hess 2008), attractiveness of the alternative(Anderson and Narus 1990; Ohanian 1990),regret(Glovich and Medvec 1995), resentment, strong desire(Alcohol Urge Questionaire: Bohn et al. 1995), perceived justice(Bies and Moag 1986; Clemmer 1993; Lind and Tyler 1998). Previous researches, such as reactance theory, emotion and service failure, have been referenced to measure constructs. All items were measured on a 7-point Likert scale ranging from "strongly disagree" to "strongly agree". We collected data involving various service field, and used 249 respondents to analyze these data using the moderated regression. The results of our analysis suggest, as expected, that the perceived severity of the switching barrier had positive effects on regret to the past choice(b = .197, p< .01), resentment to the present provider(b = .214, p< .01), and strong desire to the alternative provider(b = .254, p< .001). And the attractiveness of the alternative had positive effects on regret to the past choice(b = .353, p<.001), resentment to the present provider(b = .174, p< .01), and strong desire to the alternative provider(b = .265, p< .001). However, our findings indicate perceived justice partly moderates relationship between switching-frustrated situation and psychological negative response. The study has brought to light a number of insights between switching barriers and consumer' negative responses that have been subject to little prior research. In particular, this study adds to the existing understanding of the psychological responses to switching barriers in switching- frustrated situation. This research therefore has significance to marketers for strategic marketing programs, particularly in terms of customer retention and switching barrier strategies. Since consumers could exhibit negative responses to switching barrier, companies would be able to lose their customer when they thoughtlessly use switching barrier for remaining customer. Although the study has these contributions, there are several limitations including unsupported hypotheses and research method. So, we need to make up for these limitations in the future researches.

• Asia Marketing Journal
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• v.13 no.4
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• pp.55-76
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• 2012

Most people prefer to choose zero-cost products they may get without paying any money. The 'zero-cost effect' can be explained with a 'zero-cost model' where consumers attach special values to zero-cost products in a different way from general economic models (Shampanier, Mazar and Ariely 2007). If 2 different products at the regular prices of ￦200 and ￦400 simultaneously offer ￦200 discounts, the prices will be changed to ￦0 and ￦200, respectively. In spite of the same price gap of the two products after the ￦200 discounts, people are much more likely to select the free alternative than the same product at the price of ￦200. Although prior studies have focused on the 'zero-cost effect' in isolation of other factors, this study investigates the moderating effects of a self-regulatory resource and a construal level on the selection of free products. Self-regulatory resources induce people to control or regulate their behavior. However, since self-regulatory resources are limited, they are to be easily depleted when exerted (Muraven, Tice, and Baumeister 1998). Without the resources, consumers tend to become less sensitive to price changes and to spend money more extravagantly (Vohs and Faber 2007). Under this condition, they are also likely to invest less effort on their information processing and to make more intuitive decisions (Pocheptsova, Amir, Dhar, and Baumeister 2009). Therefore, context effects such as price changes and zero cost effects are less likely in the circumstances of resource depletion. In addition, construal levels have profound effects on the ways of information processing (Trope and Liberman 2003, 2010). In a high construal level, people tend to attune their minds to core features and desirability aspects, whereas, in a low construal level, they are more likely to process information based on secondary features and feasibility aspects (Khan, Zhu, and Kalra 2010). A perceived value of a product is more related to desirability whereas a zero cost or a price level is more associated with feasibility. Thus, context effects or reliance on feasibility (for instance, the zero cost effect) will be diminished in a high level construal while those effects may remain in a low level construal. When people make decisions, these 2 factors can influence the magnitude of the 'zero-cost effect'. This study ran two experiments to investigate the effects of self-regulatory resources and construal levels on the selection of a free product. Kisses and Ferrero-Rocher, which were adopted in the prior study (Shampanier et al. 2007) were also used as alternatives in Experiments 1 and 2. We designed Experiment 1 in order to test whether self-regulatory resource depletion will moderate the zero-cost effect. The level of self-regulatory resources was manipulated with two different tasks, a Sudoku task in the depletion condition and a task of drawing diagrams in the non-depletion condition. Upon completion of the manipulation task, subjects were randomly assigned to one of a decision set with a zero-cost option (i.e., Kisses ￦0, and Ferrero-Rocher ￦200) or a set without a zero-cost option (i.e., Kisses ￦200, and Ferrero-Rocher ￦400). A pair of alternatives in the two decision sets have the same price gap of ￦200 between a low-priced Kisses and a high-priced Ferrero-Rocher. Subjects in the no-depletion condition selected Kisses more often (71.88%) over Ferrero-Rocher when Kisses was free than when it was priced at ￦200 (34.88%). However, the zero-cost effect disappeared when people do not have self-regulatory resources. Experiment 2 was conducted to investigate whether constual levels influence the magnitude of the 'zero-cost effect'. To manipulate construal levels, 4 different 'why (in the high construal level condition)' or 'how (in the low construal level condition)' questions about health management were asked. They were presented with 4 boxes connected with downward arrows. In a box at the top, there was one question, 'Why do I maintain good physical health?' or 'How do I maintain good physical health?' Subjects inserted a response to the question of why or how they would maintain good physical health. Similar tasks were repeated for the 2nd, 3rd, and 4th responses. After the manipulation task, subjects were randomly assigned either to a decision set with a zero-cost option, or to a set without it, as in Experiment 1. When a low construal level is primed with 'how', subjects chose free Kisses (60.66%) more often over Ferrero-Rocher than they chose ￦200 Kisses (42.19%) over ￦400 FerreroRocher. On contrast, the zero-cost effect could not be observed any longer when a high construal level is primed with 'why'.