• Journal of Global Scholars of Marketing Science
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• v.17 no.2
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• pp.1-29
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• 2007

The flow theory becomes one of the most important frameworks in the internet research arena. Hoffman and Novak proposed a hierarchical flow model showing the antecedents and outcomes of flow and the relationship among these variables in the hyper-media computer circumstances (Hoffman and Novak 1996). This model was further tested after their initial research (Novak, Hoffman, and Yung 2000). At their paper, Hoffman and Novak explained that the balance of challenge and skill leads to flow which means the positive optimal state of mind (Hoffman and Novak 1996). An imbalance between challenge and skill, leads to negative states of mind like anxiety, boredom, apathy (Csikszentmihalyi and Csikszentmihalyi 1988). Almost all research on the flow 4-channel model have been focusingon flow, the positive state of mind (Ellis, Voelkl, and Morris 1994 Mathwick and Rigdon 2004). However, it also needs to examine the formation of the negative states of minds and their outcomes. Flow researchers explain play or playfulness as antecedents or the early state of flow. However, play has been regarded as a distinct concept from flow in the flow literatures (Hoffman and Novak 1996; Novak, Hoffman, and Yung 2000). Mathwick and Rigdon discovered the influences of challenge and skill on play; they also observed the influence of play on web-loyalty and brand loyalty (Mathwick and Rigdon 2004). Unfortunately, they did not go so far as to test the influences of play on state of mind. This study focuses on the relationships between state of mind in the flow 4-channel model and play. Early research has attempted to hypothetically explain state of mind in flow theory, but has not been tested except flow until now. Also the importance of play has been emphasized in the flow theory, but has not been tested in the flow 4-channel model context. This researcher attempts to analyze the relationships among state of mind, skill of play, challenge, state of mind and web loyalty. For this objective, I developed a measure for state of mind and defined the concept of play as a trait. Then, the influences of challenge and skill on the state of mind and play under on-line shopping conditions were tested. Also the influences of play on state of mind were tested and those of flow and play on web loyalty were highlighted. 294 undergraduate students participated in this research survey. They were asked to respond about their perceptions of challenge, skill, state of mind, play, and web-loyalty to on-line shopping mall. Respondents were restricted to students who bought products on-line in a month. In case of buying products at two or more on-line shopping malls, they asked to respond about the shopping mall where they bought the most important one. Construct validity, discriminant validity, and convergent validity were used to check the measurement validations. Also, Cronbach's alpha was used to check scale reliability. A series of exploratory factor analyses was conducted. This researcher conducted confirmatory factor analyses to assess the validity of measurements. All items loaded significantly on their respective constructs. Also, all reliabilities were greater than.70. Chi-square difference tests and goodness of fit tests supported discriminant and convergent validity. The results of clustering and ANOVA showed that high challenge and high skill leaded to flow, low challenge and high skill leaded to boredom, and low challenge and low skill leaded to apathy. But, it was different from my expectation that high challenge and low skill didnot lead to anxiety but leaded to apathy. The results also showed that high challenge and high skill, and high challenge and low skill leaded to the highest play. Low challenge leaded to low play. 4 Structural Equation Models were built by flow, anxiety, boredom, apathy for analyzing not only the impact of play on state of mind and web-loyalty, but also that of state of mind on web-loyalty. According the analyses results of these models, play impacted flow and web-loyalty positively, but impacted anxiety, boredom, and apathy negatively. Results also showed that flow impacted web-loyalty positively, but anxiety, boredom, and apathy impacted web-loyalty negatively. The interpretations and implications of the test results of the hypotheses are as follows. First, respondents belonging to different clusters based on challenge and skill level experienced different states of mind such as flow, anxiety, boredom, apathy. The low challenge and low skill group felt the highest anxiety and apathy. It could be interpreted that this group feeling high anxiety or fear, then avoided attempts to shop on-line. Second, it was found that higher challenge leads to higher levels of play. Test results show that the play level of the high challenge and low skill group (anxiety group) was higher than that of the high challenge and high skill group (flow group). However, this was not significant. Third, play positively impacted flow and negatively impacted boredom. The negative impacts on anxiety and apathy were not significant. This means that the combination of challenge and skill creates different results. Forth, play and flow positively impacted web-loyalty, but anxiety, boredom, apathy had negative impacts. The effect of play on web-loyalty was stronger in case of anxiety, boredom, apathy group than fl ow group. These results show that challenge and skill influences state of mind and play. Results also demonstrate how play and flow influence web-loyalty. It implies that state of mind and play should be the core marketing variables in internet marketing. The flow theory has been focusing on flow and on the positive outcomes of flow experiences. But, this research shows that lots of consumers experience the negative state of mind rather than flow state in the internet shopping circumstance. Results show that the negative state of mind leads to low or negative web-loyalty. Play can have an important role with the web-loyalty when consumers have the negative state of mind. Results of structural equation model analyses show that play influences web-loyalty positively, even though consumers may be in the negative state of mind. This research found the impacts of challenge and skill on state of mind in the flow 4-channel model, not only flow but also anxiety, boredom, apathy. Also, it highlighted the role of play in the flow 4-channel model context and impacts on web-loyalty. However, tests show a few different results from hypothetical expectations such as the highest anxiety level of apathy group and insignificant impacts of play on anxiety and apathy. Further research needs to replicate this research and/or to compare 3-channel model with 4-channel model.

• The korean journal of orthodontics
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• v.29 no.3 s.74
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• pp.383-397
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• 1999

Bone is a dynamic tissue which is constantly remodelled by subsequent cycles of bone resorption and formation. Glucocorticoid and vitamine $D_3$ are known as regulating substances in bone metabolism. In vitro experiments using bone tissue, it was suggested that glucocorticoid inhibits bone resorption, whereas the effect of glucocorticoid on bone formation are complex- increasing or decreasing effect. The active form of vitamin $D_3$, 1,25-dihydroxycholecalciferol[1.25-$(OH)_2D_3$], has been reported to stimulate osteoblastic activities including the production of ALP, type I collagen, and osteoclacin. The purpose of this study was to evaluate the effect of admixture of vitamin $D_3$ and dexamethasone, one of glucocorticoids, on osteoblastic cell line(MC3T3-E1). Alkaline phosphatase(ALP) and MTT assay were conducted in the cultivated cells with 1, 10, 100nM/ml of 1,25-$(OH)_2D_3$ and/or 10nM/ml, 100nM/ml, $1{\mu}M/ml$ of dexamethasone. The observed results were as follows. 1. The activity of osteoblastic cells with $1{\mu}M/ml$ of dexamethasone was significantly increased at 1-day cultivation with comparison to control group, but was decreased afterwards. But the activity of ALP was greatest in $1{\mu}M/ml$ of dexamethasone and increased with time lapsed. 2. The activity of osteoblastic cells with vitamin $D_3$ was significantly increased dose-dependently at 1-day cultivation, but was significantly decreased in l00nM/.ml at 2-day cultivation, and was a little increased again at 3-day cultivation. The activity of ALP was increased in 10nM/ml or 100nM/ml at 2-day or 3-day cultivation, and was greatest in 100nM/ml at 3-day cultivation. 3. In case of admixture of dexamethasone and vitamin $D_3$, the cellular activity was decreased in any concentration of vitamin $D_3$ at 2-day cultivation, but was increased again at 3-day cultivation, which was greater than that in control or dexamethasone only group. The activity of ALP was decreased at 1-day cultivation, but was increased in the admixture of 10nM/ml or 100nM/ml of dexamethasone with 100nM/ml of vitamin $D_3$ at 2-day cultivation, and was again decreased at 3-day cultivation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10407-10412
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• 2015

Background: ${\beta}$-elemene, extracted from herb medicine Curcuma wenyujin has potent anti-tumor effects in various cancer cell lines. However, the activity of ${\beta}$-elemene against glioma cells remains unclear. In the present study, we assessed effects of ${\beta}$-elemene on human glioma cells and explored the underlying mechanism. Materials and Methods: Human glioma U87 cells were used. Cell proliferation was determined with MTT assay and colony formation assay to detect the effect of ${\beta}$-elemene at different doses and times. Fluorescence microscopy was used to observe cell apoptosis with Hoechst 33258 staining and change of glioma apoptosis and cell cycling were analyzed by flow cytometry. Real-time quantitative PCR and Western-blotting assay were performed to investigated the influence of ${\beta}$-elemene on expression levels of Fas/FasL, caspase-3, Bcl-2 and Bax. The experiment was divided into two groups: the blank control group and ${\beta}$-elemne treatment group. Results: With increase in the concentration of ${\beta}$-elemene, cytotoxic effects were enhanced in the glioma cell line and the concentration of inhibited cell viability ($IC_{50}$) was $48.5{\mu}g/mL$ for 24h. ${\beta}$-elemene could induce cell cycle arrest in the G0/G1 phase. With Hoechst 33258 staining, apoptotic nuclear morphological changes were observed. Activation of caspase-3,-8 and -9 was increased and the pro-apoptotic factors Fas/FasL and Bax were upregulated, while the anti-apoptotic Bcl-2 was downregulated after treatment with ${\beta}$-elemene at both mRNA and protein levels. Furthermore, proliferation and colony formation by U87 cells were inhibited by ${\beta}$-elemene in a time and does-dependent manner. Conclusions: Our results indicate that ${\beta}$-elemene inhibits growth and induces apoptosis of human glioma cells in vitro. The induction of apoptosis appears to be related with the upregulation of Fas/FasL and Bax, activation of caspase-3,-8 and -9 and downregulation of Bcl-2, which then trigger major apoptotic cascades.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.4773-4780
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• 2014

Background: To investigate the effects of small interference RNA (siRNA) targeting BCR/ABL mRNA on proliferation and apoptosis in the K562 human chronic myeloid leukemia (CML) cell line and to provide a theoretical rationale and experimental evidence for its potential clinical application for anti-CML treatment. Materials and Methods: The gene sequence for BCR/ABL mRNA was found from the GeneBank. The target gene site on the BCR/ABL mRNA were selected according to Max-Planck-Institute (MPI) and rational siRNA design rules, the secondary structure of the candidate targeted mRNA was predicted, the relevant thermodynamic parameters were analyzed, and the targeted gene sequences were compared with BLAST to eliminate any sequences with significant homology. Inhibition of proliferation was evaluated by MTT assay and colony-formation inhibiting test. Apoptosis was determined by flow cytometry (FCM) and the morphology of apoptotic cells was identified by Giemsa-Wright staining. Western blotting was used to analyze the expression of BCR/ABL fusion protein in K562 cells after siRNA treatment. Results: The mRNA local secondary structure calculated by RNA structure software, and the optimal design of specific siRNA were contributed by bioinformatics rules. Five sequences of BCR/ABL siRNAs were designed and synthesized in vitro. Three sequences, siRNA1384, siRNA1276 and siRNA1786, which showed the most effective inhibition of K562 cell growth, were identified among the five candidate siRNAs, with a cell proliferative inhibitory rate nearly 50% after exposure to 12.5nmol/L~50nmol/L siRNA1384 for 24,48 and 72 hours. The 50% inhibitory concentrations ($IC_{50}$) of siRNA1384, siRNA1276 and siRNA1786 for 24hours were 46.6 nmol/L, 59.3 nmol/L and 62.6 nmol/L, respectively, and 65.668 nmol/L, 76.6 nmol/L, 74.4 nmol/L for 72 hours. The colony-formation inhibiting test also indicated that, compared with control, cell growth of siRNA treated group was inhibited. FCM results showed that the rate of cell apoptosis increased 24 hours after transfecting siRNA. The results of annexinV/PI staining indicated that the rate of apoptosis imcreased (1.53%, 15.3%, 64.5%, 57.5% and 21.5%) following treamtne with siRNAs (siRNA34, siRNA372, siRNA1384, siRNA1276 and siRNA1786). Morphological analysis showed td typical morphologic changes of apoptosis such as shrunken, fragmentation nucleus as well as "apoptotic bodies" after K562 cell exposure to siRNA. Western blot analysis showed that BCR/ABL protein was reduced sharply after a single dose of 50nmol/L siRNA transfection. Conclusions: Proliferation of K562 cells was remarkbly inhibited by siRNAs (siRNA1384, siRNA1276 and siRNA1786) in a concentration-dependent manner in vitro, with effective induction of apoptosis at a concentration of 50 nmol/L. One anti-leukemia mechanism in K562 cells appeared that BCR/ABL targeted protein was highly down-regulated. The siRNAs (siRNA1384, siRNA1276 and siRNA1786) may prove valuable in the treatment of CML.

• The korean journal of orthodontics
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• v.28 no.2 s.67
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• pp.297-310
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• 1998

The purpose of this study was to investigate the initial tissue change, to repair on the teeth & surrounding tissue under the intrusive orthodontic forces by use of elastic chain, through the microscopic findings. For this study, three young adult mongrel dogs were used, and were divied into three group : the control group was deliveried only casting crown and the experimental group 1 was equipped with energy chain during 1 week and experimental 2 group was deliveried using energy chain during 1 week and 3 weeks observation. All experimental groups and control groups were sacrificed to make the samples for microscopic findings on premolar teeth. All samples were examed and compared the histologic changes through the microscopic with H-E stain. The obtained results were as follows. 1. In hematoxylin-eosin stain of the control group, the periodontal ligament was constant width from apical third to cervical third of the root, and the periodontal fiber arrangement was horizontal or oblique in cervical third, oblique in middle and apical third of the root. 2. In Masson Trichrome stain of the control group, osteoblast and osteoclast appeared in cervical third of root, and bone resorption and new bone formation was observed in middle and apical third of the root. 3. In experimental 1, osteoclasts were increased highly, and hyperemia of blood vessels and new bone formation and bone resorption by reversal line in apical third of the root were seen. PDL width was increased apprarently from crest to apex of the root and more in apical third. 4. In experimental 2, osteoclasts and hyperemia of blood vessels were more increased than control material in apical third of the root. PDL width was increased more than control group in root apex, and was seen less than experimental 1. PDL arrangement was similar to experimental 1 and was mixed only in root apex. Therefore, in premolar intrusion of the young adult dog, there were increased osteoclast, hyperemia and dilation of blood vessel, resorption of alveolar bone and cementum and different arrangement of PDL in initial tissue change. There was not observed complete repair after remove intrusive force.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.3
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• pp.152-163
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• 2001

Based upon the sedimentological, geochemical and micropaleontological analyses of two sediment cores from the Antarctic Peninsula (AP), three distinct lithological units can be recognized: (1) ice-proximal an/or ice-distal diamictons in the lower part of the cores, accumulated just seaward of the grounding line of the ice shlef until 11,000 yrs BP; (2) diatomaceous mud between 6,000 and 2,500 yrs BP in the middle part, resulted from a large influx of organic materials by enhanced production of open marine condition; (3) diatomaceous sandy mud since 2,500 yrs BP, characterized by an increase in sand content and decrease in TOC and diatom abundance in the lower layers, which reflects the formation of more extensive and seasonally persistent sea ice. Based on the C-14 radiocarbon dating, the sub-ice shlef deposition of the diamicton on the AP western shelf completed around 11,000 yrs BP. Colder condition was reinstated between 12,800 and 11,600 BP with a dropin TOC content and diatom abundance, which is coincident with the Younger Dryas event in the North Atlanticregion. At this time, the ice shelf, that is now absent in the study area, appears to advance as evidenced by an abrupt increase in sea-ice taxa. A climatic optimum is recognized between 9,000 and 2,500 BP, coincide witha mid-Holocene climatic optimum 'Hypsithermal Warm Period' from the other Antarctic sites. During this time, diatomaceous mud accumulated by a large influx of organic materials by enhanced production occurred in openmarine condition. Around 2,500 BP, diatomaceous sandy mud reflects the formation of more extensive and seasonally persistent sea ice, coincident with the onset of the Neoglacial in the Antarctic. Our results provide evidence of climatic change from the Antarctic Peninsula`s western shelf that helps in determining the existence and timing of Holocene milennial-scale climatic events in the Southern Hemisphere.

• Journal of Life Science
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• v.27 no.4
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• pp.456-463
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• 2017

The purpose of this study was to investigate the effect of 3 types of medicinal herbs (Glycyrrhizae radix, Astragali radix and Dioscorea rhizoma) extracts on estrogen-like activities, proliferation and differentiation in osteoblast. Human breast cancer cell line MCF7 was transfected using an estrogen responsive luciferase reporter plasmid for measure the estrogen-like activity. Estrogen-like activities of extracts were in the range of 1.11~5.73 fold to that of negative control. The extract of G. radix showed the strongest estrogen-like activities. The estrogen-like activities of 50 and $500{\mu}g/ml$ extracts of G. radix were similar to that of $10^{-8}$ and $10^{-7}$ M standard solution ($17{\beta}-estradiol$), respectively. G. radix extract showed no cytotoxicity against osteoblast MC3T3-E1 cells at $1{\sim}1,000{\mu}g/ml$. The extract of A. radix showed no significant proliferation of osteoblast. However, the extract of G. radix and D. rhizome showed maximum 148% and 133% proliferation effects. The extract of G. radix also increased alkaline phosphatase activity and the maximum was 122% at $100{\mu}g/ml$ compared to that of control. The nodule formation by the method of the Alizarin red S staining increased compared to control. These results suggest that G. radix is able to perform the bone formation and prevent osteoporosis.

• Tuberculosis and Respiratory Diseases
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• v.44 no.6
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• pp.1225-1233
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• 1997

Background : Cervical tuberculous lymphadenitis(CTL) is one of the most common extra-pulmonary tuberculosis. Recently overall incidence of pulmonary tuberculosis has decreased, but the incidence of tuberculous lymphadenitis has not decreased. Its duration of treatment is still controversial and the pathogenesis, prognosis and relationship with other site tuberculous are poorly published. So we did a retrograde study of 120 cases of confirmed CTL about its clinical manifestations. Method : All patients were applied fine needle aspiration(FNA) of palpable enlarged cervical lymph nodes and 114 patients were examined for AFB smear and 34 patients for TB culture with aspirated fluid. 57 patients were examined Mantoux test(5TU with PPD-S). With above methods, a total of 120 patients was diagnosed as having CTL. Results : 1) CTL is most prevalent in young women between the age of 20~30 years and the incidence of CTL in female is 2.5 times higher than that of male. It is located most commonly in the posterior cervical area. The most common presenting symptom is painless palpable enlarged cervical lymph nodes. 2) With FNA of enlarged cervical lymph nodes, the percentage of histopathological positivity is 82.3%. The percentage of AFB smear positivity is 38.6%, and that of TB culture positivity is 17.6%(p<0.001). 3) Pulmonary tuberculosis is noted in 79 cases(65.8%). And 42 cases(53.5%) of them had minimal pulmonary tuberculosis. In 14 cases(11.7%), other extrapulmonary tuberculosis coexsisted and pleural tuberculosis was most Common in the order. 4) CTL was treated with anti-tuberculous medication(first line drug) and median treatment duration was 18.5months. During treatment, the size of involved lymph nodes decreased gradually in 62 cases(75.8%), newly developed lymph nodes were found in 25 cases(30.4%), fluctuation formation in 22 cases(26.8%) and fistula formation in 14 cases(17.0%). Conclusion : CTL is prevalent in women between the age of 20~40 years and it involves posterior cervical area most commonly. CTL is treated with long-term anti-tuberculous chemotherapy. We think it is one manifestation of systemic disease and frequently coexisting with pulmonary tuberculosis. Despite anti-tuberculous chemotherapy, the size of involved lymph nodes was increased, new lymph nodes were developed or fluctuation and fistula formed in involved lymph nodes. After sufficient medication, when the patient felt pressure discomfort from enlarged lymph node or fistula was formed, we recommended total excision of involved lymph nodes.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.532-537
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• 2011

'Seolgaeng' is a new Japonica rice variety developed from an 'Ilpumbyeo' mutant line, N-methyl-N-nitrosourea (MNU) treatment on fertilized egg cell, by a rice breeding team of National Crop Experiment Station, Rural Development Administration in 2001. This variety has about 134 days of growth duration from transplanting to harvesting in central plain area of Korea, a good semi-elect plant type and resistant to lodging with strong culm. The number of panicles/hill of 'Seolgaeng' is more than that of 'Hwaseongbyeo'. The milled rice appearance of this cultivar is an opaque, but it has amylose content (19.3%) similar to 'Hwaseongbyeo'. It is superior to hypae formation of Aspergillus orzyae in the making of fermented rice and amount of pigmentation in fermented rice by Monascus anka that of 'Ilpumbyeo'. This variety showed slow leaf senescence and considerable resistance to viviparous germination. It is moderately resistant to leaf blast and susceptible to bacterial blight, virus disease and insect pests. The yield performance of this rice cultivar is about 5.27 MT/ha in milled rice in local adaptability test for three years from 1999 to 2001). 'Seolgaeng' is adaptable to central and southern plain areas of Korea.

• (The)Study of the Eastern Classic
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• no.34
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• pp.225-255
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• 2009

Few data on the epigraph from the Bal-Hae Dynasty have been reported so far. The present paper, based on an examination of the style of the epitaphic tombstones of Princess Jeong-Hye and Princess Jeong-Hyo, investigates the historical formation and characteristics of Balhae's epitaphic style and its influences on the posterior periods. The epitaphs from the Bal-Hae Dynasty have the following epigraphic characteristics and historical significances. First, Bal-Hae's epitaphs are similar to those from the Goguryeo Dynasty in the sense that they are angular in their form. Tombstones with angular head first appeared during the East Han period. During the Wi-Jin period, however, as tombstones were not allowed to be erected in front of the tomb, small-sized epitaphic tombstones were set up inside tombs. Typical tombstones from the Dang Dynasty had stone pole and square cover. Unlike those from the Dang and the Tong-Il Silla Dynasties, however, the epitaphs from Bal-Hae had angular head in their tombstone body. The Bal-Hae's angular headed tombstones are very likely to testify that Goguryeo's epitaphs, which features an influence from the Wi-Jin Nambuk-Jo period, in turn exerted an effect on those from the Bal-Hae Dynasty. Second, Bal-Hae's epitaphic tombstones are characterized by their hexagonal head,which were modified from the then typical pentagonal head by cutting out the sharp point. The hexagonal head, which has not been found in its neighboring countries during the same historical period, is peculiar to the epitaphic tombstones from the Bal-Hae Dynasty. Third, the edge lines and ornamental figures first appeared in Bal-Hae's epitaphic tombstones, as seen in those of Princess Jeong-Hye. In the fa?ade of the epitaphic tombstone, a carved line demarcates its rectangular body and trapezoidal head. Four faces of the body stonehave two parallel lines in their edges within which vignette was inscribed, and the trapezoidal head part was ornamented with flower figures. Fourth, Bal-Hae's epitaphic tombstone had an extensive influence on the posterior countries in its neighborhood. The epitaphic tombstones in the Bal-Hae style are very often found in those of the Goryeo Dynasty and the Yo Dynasty which were greatly influenced from Bal-Hae. The vestiges of Bal-Hae's epitaphic style are also found in those from the Song, the Geum, and the Won Dynasties.