• The Journal of the Petrological Society of Korea
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• v.20 no.2
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• pp.77-98
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• 2011

The igneous complex consisting of mangerite and gabbro in the Odaesan area, the eastem part of the Gyeonggi Massif, South Korea, intruded early Paleo-proterozoic migmatitic gneiss. The mangerite is composed of orthopyroxene, clinopyroxene, amphibole, biotite, plagioclase, pethitic K-feldspar, quartz. The gabbro has similar mineral assemblage but gabbro has minor amounts of amphibole and no perthitic K-feldspar. The gabbro occurs as enclave and irregular shaped body within the mangerite, and the boundary between the mangerite and gabbro is irregular. Leucocratic lenses with perthitic K-feldspar are included in the gabbro enclaves. These textures represent mixing of two different magmas in liquid state. SHRIMP U-Pb zircon age dating gave $234{\pm}1.2$ Ma and $231{\pm}1.3$ Ma for mangerite and gabbro, respectively. These ages are similar with the intrusion ages of post collision granitoids in the Hongseong (226~233 Ma) and Yangpyeong (227~231 Ma) areas in the Gyeonggi Massif. The mangerite and gabbro are high Ba-Sr granites, shoshonitic and formed in post collision tectonic setting. These rocks also show the characters of subduction-related igneous rock such as enrichment in LREE, LILE and negative Nb-Ta-P-Ti anomalies. These data represent that the mangerite and gabbro formed in the post collision tectonic setting by the partial melting of an enriched lithospheric mantle during subduction which occurred before collision. The heat for the partial melting was supplied by asthenospheric upwelling through the gab between continental and oceanic slabs formed by slab break-off after continental collision. The distribution of post-collisional igneous rocks (ca. 230 Ma) in the Gyeonggi Massif including Odaesan mangerite and gabbro strongly suggests that the tectonic boundary between the North and South China blocks in Korean peninsula passes the Hongseong area and futher exteneds into the area between the Yangpyeong-Odaesan line and Ogcheon metamorphic belt.

• Management & Information Systems Review
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• v.34 no.3
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• pp.273-302
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• 2015

This empirical study analyzed the influence of transformational leadership on knowledge management activities and organizational commitment, and examined the mediating effect of knowledge management in the relationship between transformational leadership and organizational commitment. A survey was employed as the research method. The survey targeted 635 participants working in the service, manufacturing, and IT industries. The results were used to compare and analyze the relationships among industry-specific variables. Transformational leadership is defined as the tendency to strive for change and innovation despite the achievement of objectives, develop the potential capabilities and strengths that each member of the organization possesses, amplify their self-esteem and passion, and lead them to surpass their expected objectives by stimulating positive strengths. Such type of leadership has been perceived as a precedent that enhances organizational effectiveness. In summary, this study has yielded the following results: First, the transformational leadership exhibited by organizational leaders was found to have a significant positive impact on knowledge management activities as well as organizational commitment. Second, knowledge management activities were found to have a significant positive influence on organizational commitment. Third, the transformational leadership exhibited by organizational leaders was found to have a partial mediating effect on the mediating role of knowledge management activities in the relationship with organizational commitment. Fourth, analyzing industry-wise, the influence of transformational leadership on knowledge management activities was the most significant in the service industry, which was also the case for the influence of knowledge management activities on organizational commitment. The influence of leaders' transformational leadership on organizational commitment was the most significant in the information technology industry. Finally, based on the aforementioned research results, suggestions were made regarding the meaning of the influence of transformational leadership on knowledge management activities and organizational commitment and the differences by industry thereof, while also suggesting the limitations of this work.

• The Korean Journal of Mycology
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• v.17 no.2
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• pp.82-90
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• 1989

Detection of antibody against pathogenic fungi in serum specimens of the patients with pulmonary tuberculosis or other lung diseases has been carried out(male) using the indirect fluorescence antibody technique and immunodiffusion tests. Immunodiffusion tests revealed that 104(36.5%) out of 285 patients examined showed a positive precipitin reaction against one or more of fungal antigens. The majority of ID positive patients 64(61.5%) reacted with Aspergillus fumigatus antigen and 49(47.1%) patients reacted with Candida albicans antigen ID positive reaction to A. fumigatus was found little more frequently among male patients, while Candida albicans reactors were found more frequently among female patients. Age distribution of ID positive reactors was high(49.1-43.3%) in age group of 40-59 years, but least or none in age group of less than 30 years. Age of fungal mycelium used as antigen did not effect sensitivity of the indirect flubrescence (IF) technique in detecting antibody to A. fumigatus. Antibody class against A. fumigatus that showed highest titer was IgG and thus FITC labeled anti-IgG immunoglobulin shoul be preferable. As relatively large amount of cell wall components of Aspergilli shared antigenically, a considerable cross-reaction was observed among A. fumigatus, A. flavus and A. niger, but not much with C. albicans. While (IF) has much better sensitivity when compared with ID, relative specificity of the latter procedure cannot to be overried, so that they could be batter used together in order to obtain quantitative measurement of antibody with relative specificity.

• Radiation Oncology Journal
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• v.16 no.3
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• pp.259-264
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• 1998

Purpose : This study was to evaluate the effectiveness of preoperative radiotherapy in maxillary sinus cancer. Materials and Methods : A retrospective analysis was done for 42 patients with maxillary sinus cancer who were treated with radiation with or without surgery from April 1986 to September 1996. There were 27 male and 15 female patients. Patients' age ranged from 24 to 75 years (median 56 years). Stage distribution showed 2 in T2, 19 in T3, and 21 in T4 lesions The histologic type was squamous cell carcinoma in 38, undifferentiated carcinoma in 1, transitional cell carcinoma in 1, and adenoid cystic carcinoma in 2 patients. All patients were treated with radiation initially with a dosage range of 50.4-70.2 Gy (median 70.2 Gy) before further evaluation of remnant disease. Eleven patients were given induction chemotherapy (2cycles of 5-fluorouracil and cisplatin) concurrently with radiotherapy. Six to eight weeks after radiotherapy with or without chemotherapy computerized tomography (CT) of paranasal sinus was taken to evaluate remnant disease. If the CT finding showed remnant disease, a Caldwell-Luc procedure was done to get the specimen of suspicious lesions. A radical maxillectomy was done if the specimen was proven to contain malignancy. In contrast periodic follow-up examination was done without any radical surgery if the tissue showed only granulation tissue. Follow-up period ranged from 3 to 92 months with a median 16 months. Results : Nine (21.4$\%$) patients showed complete response (CR) and 33 patients (78.6$\%$) showed persistent disease (PER) to initial radiotherapy. Among the 9 CR patients, 7 patients had no evidence of disease (NED), 1 patient had local failure, and 1 patient had regional failure. Among 33 PER patients, salvage total maxillectomy was done in 10 patients, and the surgery was not feasible or refused in 23 patients. Following the salvage radical surgery, 2 patients were NED and 8 patients were PER status. Overall and disease- free survival rate at 5 years was 23.1$\%$ and 16.7$\%$, respectively. The only factors associated with the overall survival rate was the response to radiotherapy (P<0.01). Conclusion : The only factors associated with the overall survival rate was the response to radiotherapy. We could omit a radical mutilating surgery by preoperative irradiation in 7 of 42 patients (21.4$\%$) so as to preserve their facial integrity.

• Radiation Oncology Journal
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• v.18 no.4
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• pp.283-292
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• 2000

Purpose :A retrospective review of 72 patients with locally advanced gallbladder carcinoma, between January 1990 and December 1996, was peformed. Survival results and prognostic factors are analyzed for the patients treated with a various modalities. Materials and Methods :We patients were classified by treatment modality: group 1 included to 27 patients treated with palliative surgery alone, and group 2 for 11 patient treated with palliative surgery and radiotherapy; group 3 for 18 patients not treated by any treatment modality, and group 4 for 16 patients treated with radiotherapy alone. Age distribution ranged from 35 to 80 years with mean of 63 years. The stage was classified by TNM and Nevin's staging system; all patients had an advanced stage more than III. Palliative surgery was done in .: patients and adiuvant radiation therapy (RT) was followed in 11. For 34 patients, in whom no resection was tried, definitive RT was done in 16. Radiation delivered to tumor site and draining nodes up to 45~61.2 Gy using 10 MV linear accelerator. Chemotherapy was given to 25 patients with 5-FU based regimens. Results :Modian suwival time was 10.3 months and 3-year survival rates (3-YSR) were 13.0$\%$ in all patients. Survival rates according to the treatment modalities were as followed; in palliative surgery alone, 3-YSR was 2.5$\%$; in palliative surgery and adjuvant RT, 3-YSR was 45.5$\%$, in no treatment group, 3-VSR were 8.3$\%$; and definitive RT was 13.1$\%$. It was better survival in additional RT after palliative surgery group than palliative surgery alone (p=0.0009). It was better survival in definitive RT group than no treatment group (p=0.002). Significant prognostic factors by univariate analysis were treatment moonlities, the type of tumor and TNM stage. Significant prognostic factors by multivariate analysis were treatment modalities, the type of tumor and the presence of jaundice. Conclusion : It is suggested that RT could be potentially of effective as adjuvant treatment modalities after palliative surgery or primary treatment for locally advanced and unresectable gallbladder carcinoma.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.442-447
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• 1994

Effect of different mixing ratio of non-glutinous and glutinous rice on physical and rheological properties of extrudate prepared in a single screw extruder were examined. The extrusion conditions in term of screw speeds, moisture content and die temperature were 258 rpm, 18% and $120^{\circ}C$, respectively. The resisdence time distribution of the most of materials were within 30 second and small portion of them went up to 80 second. The expansion ratio was the highest value (2.93) for 70% of glutinous rice in the mixture, while the lowest value for 100% of non-glutinous rice. Breaking strength was in the range between 1,051g and 1,117g for $10{\sim}20%$ of glutinous rice in the mixture, while the lowest value (737g) for 80%r of glutinous rice. As the amount of glutinous rice increased, L and a values were increased and b value was decreased. The uncooked cold paste viscosity had 400 B.U. for 100% non-glutinous rice , while no peak for the 100% glutinous rice. As the amount of glutinous rice increased up to 100%, the water absorption index (WAI) was decreased, while water solubility index (WSI) was increased. The rheological properties of extrudate were accounted by the law of Oswald. The flow behavior index of extrudate was less than 1.0, which showed pseudoplastic behavior. Yield stress was the highest value for 20% of glutinous rice in the mixture and the lowest value for $80{\sim}100%$ of glutinous; rice. Number of air cell was between 128 and 159 for $80{\sim}100%$ of glutinous rice in the mixture, while $81{\sim}84%$ for $0{\sim}20%$ of glutinous rice. The degree of shapefact was increased more when the mixtures of glutinous and non-glutinous rice was used than when glutinous or non-glutinous rice was only used.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.733-742
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• 2000

Fundamental materialistic characterization and adsorption/neutralization behavior of waste egg shell for heavy metal ion have been studied for its application to wastewater treatment. To investigate the structural change and thermal decomposition characteristics of egg shell. X-ray diffraction and FT-IR analysis were conducted for egg shell treated at $105^{\circ}C$ and $700^{\circ}C$, respectively. For the result of FT-IR analysis, the sample treated at $700^{\circ}C$ showed a reduced C-O absorption band compared with that of egg shell treated at $105^{\circ}C$, which may be due to the $CO_2$ release. Unlike to the result of FT-IR analysis, the XRD patterns of egg shell were almost similar for the cases of $105^{\circ}C$ and $700^{\circ}C$ treatment. however, characteristic diffraction pattern of CaO was observed for $850^{\circ}C$ treatment, at which $CaCO_3$ is known to be completely converted to CaO. TGA/DTA analysis showed a slow decline in weight loss up to $600^{\circ}C$ and, for $600{\sim}800^{\circ}C$ range, the weight loss became drastic by reason of $CO_2$ discharge, which was accompanied by an appearance of major endothermic peak. The ratio of practical breakthrough time to ideal one, total transfer unit, and mass transfer coefficient were observed to be increased as the adsorption was progressed in a multiple-column fixed-bed reactor using egg shell as an adsorbent, which signified the distribution effect of mass transfer for continuous adsorption reaction. The neutralization effect of egg shell for several types of acidic wastewater made of different mineral acids was not much different from each other except for the case of $H_2SO_4$, for which the neutralization reaction was thought to be retarded by the formation of gypsum.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.424-434
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• 2009

Statement of problem: Problems such as loosening and fractures of retained screws and fracture of implant fixture have been frequently reported in implant prosthesis. Purpose: Implant has weak mechanical properties against lateral loading compared to vertical occlusal loading, and therefore, stress analysis of implant fixture depending on its material and geometric features is needed. Material and methods: Total 28 of external hexed implants were divided into 7 of 4 groups; Group A (3i, FULL $OSSEOTITE^{(R)}$Implant), Group B (Nobelbiocare, $Br{\aa}nemark$ $System^{(R)}$Mk III Groovy RP), Group C (Neobiotec, $SinusQuick^{TM}$ EB), Group D (Osstem, US-II). The type III gold alloy prostheses were fabricated using adequate UCLA gold abutments. Fixture, abutment screw, and abutment were connected and cross-sectioned vertically. Hardness test was conducted using MXT-$\alpha$. For fatigue fracture test, with MTS 810, the specimens were loaded to the extent of 60-600 N until fracture occurred. The fracture pattern of abutment screw and fixture was observed under scanning electron microscope. A comparative study of stress distribution and fracture area of abutment screw and fixture was carried out through finite element analysis Results: 1. In Vicker's hardness test of abutment screw, the highest value was measured in group A and lowest value was measured in group D. 2. In all implant groups, implant fixture fractures occurred mainly at the 3-4th fixture thread valley where tensile stress was concentrated. When the fatigue life was compared, significant difference was found between the group A, B, C and D (P<.05). 3. The fracture patterns of group B and group D showed complex failure type, a fracture behavior including transverse and longitudinal failure patterns in both fixture and abutment screw. In Group A and C, however, the transverse failure of fixture was only observed. 4. The finite element analysis infers that a fatigue crack started at the fixture surface. Conclusion: The maximum tensile stress was found in the implant fixture at the level of cortical bone. The fatigue fracture occurred when the dead space of implant fixture coincides with jig surface where the maximum tensile stress was generated. To increase implant durability, prevention of surrounding bone resorption is important. However, if the bone resorption progresses to the level of dead space, the frequency of implant fracture would increase. Thus, proper management is needed.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.310-322
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• 2000

The objectives of this study were to classify the types of vegetation in Pinus densiflora for. erecta stands. The study sites were located at Sokwang-Ri, Mt. Chungok(1,276m), Uljin, Mt. Kumma(1,017m) and Mt. Eungbong(1,267m). Two hundred thirty releves were classified and explained by phytosociological analysis(the method of ZM schools), and the results were summarized as follows. Pinus densiflora for. erecta stands were classified into Vaccinium koreanum community, Rhododendron micranthum community, Quercus dentata community, Acer pseudosieboldianum community, and Typical community. Quercus dentata community was divided into Festuca ovina group, Robinia pseudoacacia group, and Typical group, and Acer pseudosieboldianum community was divided into Hydrangea serrata for. acuminata group, Disporum smilacinum group, Magnolia sieboldii group, Carpinus laxiflora group, and Typical group, and Typical community was divided into Melampyrum roseum group and Typical group. And some groups were divided into 7 subgroups. Therefore, Pinus densiflora for. erecta stands had total of 16 vegetation units, out of those units, Vaccinium koreanum community distributed all over the studied areas. While Rhododendron micranthum community distributed mainly at Sokwang-Ri and Mt. Chungok. Therefore it was considered to be useful indicator in determining the range of afforestation and natural distribution of Pius densiflora for. erecta stands. The classified vegetation units were investigated by using of coincidence method. The results indicated that Quercus dentata community distributed mainly below 100 meters at the sea level, while other communities distributed above 350 meters at the sea level. According to the correlations between vegetation units and topography, Vaccinium koreanum and Rhododendron micranthum communities distributed mainly above middle slope areas, Quercus dentata community distributed mainly from lower slope to upper slope areas, Acer pseudosieboldianum community distributed mainly between valley and lower slope areas, and Typical community distributed mainly above upper slope areas. According to the correlations between vegetation units and 5 study areas, Quercus dentata community was distributed in the region of Uljin, and other communities were evenly distributed over other studied areas. According to the correlations between the units and aspects, all communities occurred all aspects, but most of the communities tended to be more distributed at south slopes than at north slopes, which meant that the relic stands of Pinus densiflora for. erecta were remained largely as patch phase status at south slopes.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.34-43
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• 1996

We investigated the vegetation structure, and effects of canopy degree(gap or purlieu to 25%, 50%, 75%, over 75%) of the overstory on seedling regeneration and survivorship, and sapling density, growth and growth type of Abies koreana in subalpine of Mt. Chiri. The stem density in Abies koreana stand was higher in middle story than upper story, individual trees in upper story occupied larger area and were more apart, resulted in uniform distribution. The regeneration and survivorship of seedlings and saplings were best in 25% of crown closure, in order of 50%, gap, but lowest in over 75% of crown closure. The annual growth rate and recent 5 years growth rate of saplings were highest in gap or purlieu and getting lower toward gradually higher coverage of overstory. And 10- to 20-Year-old saplings were mainly regenerated in stands with lower density(I or II), but most of 20 to 30 years old saplings were growing in stands with higher density (III or IV). The number of "A" type saplings grown normally in gap or purlieu was gradually decreased in stand with higher density but the number of "D" or "E" types of which growth was supressed or prohibited by the high density was abruptly increased. Saplings normally growing in the gap and purlieu showed the panicle type, but those grown under dense crown were greatly suppressed and showed the umbellate type.