• Economic and Environmental Geology
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• v.28 no.3
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• pp.185-197
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• 1995

Tungsten skarns in the Chungju mine which consists mainly of strata-bound type iron ore deposits are found in the vicinity of the contact between the age-unknown Kyemeongsan Formation and granitic rock intrusions of Mesozoic age($134{\pm}2Ma$). Tungsten skarns were formed extensively from alumina and silica-rich schistose rocks by the introduction of calcium and iron from hydrothermal solution. The skarns comprise a metasomatic column and are subdivided into four facies; garnet facies, wollastonite facies, epidote facies and chlorite facies. The skarn process in time-evolutional trend can be divided broadly into the four facies in terms of the paragenetic sequence of calc-silicates and their chemical composition. Skarn and ore minerals were formed in the following sequence; (1) garnet facies, adjacent to biotite granite, containing mainly garnet(>Ad96) and magnetite, (2) wollastonite facies containing mainly wollastonite and garnet(Ad95~60), (3) epidote facies, containing mainly epidote(Ps35~31), quartz, andradite-grossular(Ad63~50), and scheelite, (4) chlorite facies, adjacent to and replacing schist, containing mainly chrolite, muscovite, quartz, calcite, epidote(Ps31~25), hematite and sulfides. The mineral assemblage and mineral compositions. suggest that the chemical potentials of Ca and Fe increased toward the granitic rock, and the component Al, Mg, K, and Si decreased from the host rock to granitic rock. The homogenization temperature and salinity of fluid inclusion in scheelite, quartz and epidote of epidote facies skarn is $300-400^{\circ}C$ and 3-8wt.% eqiv. NaCl, respectively. ${\delta}^{34}S$ values of pyrite and galena associated with chlorite facies skarn is $9.13{\sim}9.51%_{\circ}$ and $5.85{\sim}5.96%_{\circ}$, respectively. The temperature obtained from isotopic com· position of coexisting pyrite-galena is $283{\pm}20^{\circ}C$. Mineral assemblages and fluid inclusion data indicate that skarn formed at low $X_{CO_2}$, approximately 0.01. Temperature of the skarn mineralization are estimated to be in the range of $400^{\circ}C$ to $260^{\circ}C$ and pressure to be 0.5 kbar. The oxygen fugacity($fo_2$) of the skarn mineralization decreased with time. The early skarn facies would have formed at log $fo_2$ values of about -25 to -27, and late skarn facies would have formed at log $fo_2$ values of -28 to -30. The estimated physicochemical condition during skarn formation suggests that the principal causes of scheelite mineralization are reduction of the ore·forming fluid and a decrease in temperature.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.1
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• pp.35-40
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• 1983

This study was conducted to investigate the effect of some kinds of tree litters covered the soil surface on the germination, establishment, sward composition, and herbage production of the grasses sown by the oversowing method. The litters were leaves of Pinus rigida Miller, Quercus variabilis Blume, Larix leptolepis Gord, and Alnus hirsuta Rupr. The results obtained were as follows; 1. In the Petri dish, germination was affected by grass species and kinds of litters, especially the percolate from Pinus litter seriously suppressed the early germination of small size seeds such as ladino clover and timothy. 2. In the pot, establishment was slightly suppressed in ladino and timothy by the percolate from Pinus litter, while in others it was decreased relatively. 3. Among the 6 species investigated, the small size seeds of ladino clover and timothy and the large size seeds of red clover, they could be early put into the litter spaces and established well. 4. In Larix litter, the establishment percentage of all species were decreased seriously owing to low moisture retention capacity. 5. Grass height and root length were different in kinds of litters and species. 6. The percentages of establishment on each surface treatments of burning, treading, raking, and the control under Quercus tree were 36, 46, 37, and 31%, respectively. 7. The sward percentage of oversown grasses and legumes was 57.8% in burning, 70.9% in treading, 59.6% in raking, and 54.0% in the control. 8. Treading treatment was most effective to destroy existing vegetation and improve soil-seed contact when oversowing and showed the best result. 9. Yield of dry matter per unit area in treading treatment was higher (p<0.05) than those of the other treatments. The above experimental results suggest the importance of direct oversowing on the litters in the mountainous land and forest land.

• Journal of Korean Academy of Nursing
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• v.28 no.4
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• pp.958-969
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• 1998

In this study, we attempted to investigate the needs and problems of the terminal cancer patients and their family caregivers to provide them with nursing information to improve their quality of life and prepare for a peaceful death. Data was collected from August 1, 1995 to July 31, 1996 at the internal medicine unit of S hospital in Seoul area with the two groups of participants who were family members of terminal cancer patients seventy four of them were in-patients and 34 were out-patients who were discharged from the same hospital for home care. The research tool used in this study has been developed by selecting the questionnaires from various references, modifying them for our purpose and refining them based on the results of preliminary study. While general background information about the patients was obtained by reviewing their medical records, all other information was collected by interviewing the primary family caregivers of the patients using the questionnaire. The data collected were analyzed with the SPSS PC/sup +/ program. The results of this study are summarized as follows ; 1) Most frequently complained symptoms of the terminal cancer patients were in the order of pain(87%), weakness(86.1%), anorexia(83.3%) and fatigue (80.6%). 2) Main therapies for the terminal cancer patients were pain control (58.3%), hyperalimentation(47.2%) and antibiotics(21.3%). 3) Special medical devices that terminal cancer patients used most were oxygen device (11.1%), and feeding tube(5.6%). Other devices were used by less than 5% of the patients. 4) The mobility of 70.4% of the patients was worse than ECOG 3 level, they had to stay in bed more than 50% of a day. 5) Patients wanted their medical staffs to help relieve pain(45.4%), various physical symptoms(29.6%), and problems associated with their emotion(11.1%). 6) 16.7% of the family caregivers hoped for full recovery of the patients, refusing to admit the status of the patients. Also, 37% wished for the extension of the patient's life at least for 6 months. 7) Only 38.9% of the family members was preparing for the patient's funeral. 8) 45.4% of family caregivers prefer hospital as the place for the patient's death, 39.8% their own home, and 14.8% undetermined. 9) Caregivers of the patients were mostly close family members, i.e., spouse(62%), and sons and daughters or daughter-in-laws(21.3%). 10) 43.5% of the family caregivers were aware of hospice care. 46.8% of them learned about the hospice care from the mass media, 27.7% from health professionals, and the rest from books and other sources. 11) Caregivers were asked about the most difficult problems they encounter in home care, 41 of them pointed out the lack of health professionals they can contact, counsel and get help from in case of emergency, 17 identified the difficulty of finding appropriate transportation to hospital, and 13 stated the difficulty of admission in hospital as needed. 12) 93.6% of family caregivers demanded 24-hour hot line, 80% the visiting nurses and doctors, and 69.4% the volunteer's help. The above results indicate that terminal patients and their family caregivers demand help from qualified health professionals whenever necessary. Hospice care system led by well-trained medical and nursing staffs is one of the viable answers for such demands.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.6
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• pp.469-477
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• 2009

Purpose: This study was performed to evaluate the effect of various graft materials used with a titanium cap on the ability of new bone formation in the rabbit calvarium. Materials and Methods: A total of 32 sites of artificial bony defects were prepared on the calvaria of sixteen rabbits by using a trephine bur 8 mm in diameter. Each rabbit had two defect sites. 0.2 mm deep grooves were formed on the calvaria of sixteen rabbits by using a trephine bur 8 mm in diameter for the fixation of a titanium cap. The treatments were performed respectively as follows: without any graft for the control group (n=8), autogenous iliac bone graft for experimental group 1 (n=8), alloplastic bone graft ($SynthoGraft^{(R)}$, USA) for experimental group 2 (n=8), and xenogenic bone graft ($NuOss^{(R)}$, USA) for experimental group 3 (n=8). After the treatments, a titanium cap (8 mm in diameter, 4 mm high, and 0.2 mm thick) was fixed into the groove. At the third and sixth postoperative weeks, rabbits in each group were sacrificed for histological analysis. Results: 1. In gross examination, the surgical sites showed no signs of inflammation or wound dehiscence, and semicircular-shaped bone remodeling was shown both in the experimental and control groups. 2. In histological analysis, the control group at the third week showed bone remodeling along the inner surface of the cap and at the contact region of the calvarium without any specific infiltration of inflammation tissue. Also, there was no soft tissue infiltration. Bone remodeling was observed around the grafted bone and along the inner surface of the titanium cap in experimental group 1, 2, and 3. 3. Histologically, all groups at the sixth week showed the increased area of bone remodeling and maturation compared to those at the third week. In experimental group 2, the grafted bone was partially absorbed by multi nucleated giant cells and new bone was formed by osteoblasts. In group 3, however, resorption of the grafted bone was not observed. 4. Autogenous bone at the third and sixth week showed the most powerful ability of new bone formation. The size of newly formed bone was in decreasing order by autogenous, alloplastic, and heterogenous bone graft. There was no statistically significant difference among autogenous, alloplastic, and heterogenous bones(p>0.05). Summary: This result suggests that autogenous bone is the best choice for new bone formation, but when autogenous bone graft is in limited availability, alloplastic and xenogenic bone graft also can be an alternative bone graft material to use with a suitably guided membrane.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.528-547
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• 2001

The blastoporphyritic granite gneiss (BPGN) including much alkali-feldspar megacrysts occurs in Jiri mountains area, southwestern part of Sobaegsan massif, Korea. The BPGN is formed gneiss complexes with other gneisses in Precambrian. The BPGN was named as porphyroblastic gneiss with porphyroblasts of alkali-feldspar megacrysts by other researchers, but the BPGN includes of euhedral alkali-feldspars (microcline), and the boundary with the granitic gneiss represents sharp contact as intrusive relationship. The BPGN mainly composes of alkali-feldspar megacrysts, quartz, plagioclase, K-feldspar and biotite some almandine and accessary minerals are muscovite, chlorite, apatite, zircon and opaques. The alkali-feldspar is microcline with perthitic texture. An content of plagioclases show 30 to 40. Biotites occur two type, one is Brown biotite which shows compositional ranges of Mg/Fe+Mg ratios from 0.38 to 0.52, the other is Green Bt. which is retrograde product. Camels to be various sizes and shapes have composition of almandine with 73 to 80 mole percent, but represent retrogressive zoning from core (X$_{pyr}$: 15.9${\sim}$20.8) to rim (X$_{pyr}$:13.7${\sim}$15.9) to be evidence of retrograde metamorphism. Megacrysts of alkali-feldspar in the BPGN show rectangular shape of euhedral and some become ellipsoidal or spheroidal in shape and the average size up to 20 cm long. The megacryst includes of biotite, plagioclase and quartz, and rarely euhedral apatite as inclusions. In petrochemistry the BPGN represents granodiorite composition, characteristics of peraluminous S-type granitoid and calc-alkaline features.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.201-219
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• 2014

The Republic of Korea in the real economy to a knowledge economy, and a center of creativity and imagination in the creative economy is changing the paradigm. As the core of creating economic, creative industries with the technology and information play an important role in the industry individuals. In order to solve the problem of the polarization of the economy and high youth unemployment rate of Korea, to recognize the role of the creative industries, as objection part, dimensions pan-national and one creative companies in industries of Mobile Apps various policies that support has been promoted. Support these policies to be able to contribute to the establishment of the success of mobile apps one-person creating company, we performed this study targeting one-person company that creates mobile apps area, we conducted a demonstration study of success factors, and thus more effective and efficient in an attempt to seek out support measures. In this study, we derive a research 4 hypothesis about the success factors of one creative enterprise through literature discussion, a study was made on the basis of empirical data of one-person company that creates mobile apps. The results of the analysis, first, if the development rate of the mobile application technology is fast and a new competition associated product is appeared, it was possible to find a tendency to be higher at the performance quantitative companies. Second, if the founder is a founding for the benefit and rewarding work and come to terms with the risk, it was possible to discover tends to be higher achievement quantitative. Third, if one-person company select a target market with capture intensively, it was possible to find a tendency for higher qualitative results. Fourth, it could be found that the reliability of the contact frequency of the network related performance business environment these characteristics enterprise management strategy and act as a significant modulatory effect. Provision of information relating to management and entrepreneurship education to be one creative enterprise is required, these results suggest that there is a provision continuing need for the opportunity to be able to meet and network and reliable variety have. In this study, to take advantage to promote the elimination measures that can increase the likelihood of success of the company of institutions to support one company that creates knowledge-based, such as in the field of mobile application.

• Economic and Environmental Geology
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• v.53 no.1
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• pp.45-69
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• 2020

In Danyang area, various geological structures as well as various lithology and strata are well developed, which are useful for studying paleo-environment and structural movements, and also typical karst landforms, wethering landforms and river landforms. If geologically and geomorphologically valuable resources are used in terms of geotourim perspective, it is expected that revitalization of regional economy through diversification of attracting factors and employment creation of local people. Danyang has many excellent geological resources for geological field trip, they can greatly contribute to the development of geology such as expanding the base of geology and cultivating successive generations. In this study, we have evaluated newly discovered sites and previously excavated resources based on academical and educational values. By using these geological and geomorphological resources, we suggest three geotrail courses as follows. First, Geo-trail A is mainly focused on geological structures (Route A: Jeong Hwan Route), where we can learn geological deformation and movement through various brittle and ductile deformation structures. Second, Geo-trail B is mainly focused on stratigraphic importance (Route B: Soon-Bok Route), which emphasizes on various rocks, strata and contact relationship. Third, Geo-trail C is mainly focused on geomorphological landforms and landscapes (Route C: Satgat Route), which provide information about different geomorphological landforms and the interaction between different geological agents. In order to operate these geotrail courses efficiently, installation of explanation boards and view points, cultivate local commentators, and visitor centers and experience programs should be properly prepared together.

• Journal of the Korean Society of Radiology
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• v.11 no.7
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• pp.547-553
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• 2017

In the current medical field, lead is widely used as a radiation shield. However, the lead weight is very heavy, so wearing protective clothing such as apron is difficult to wear for long periods of time and there is a problem with the danger of lethal toxicity in humans. Recently, many studies have been conducted to develop substitute materials of lead to resolve these problems. As a substitute materials for lead, barium(Ba) and iodine(I) have excellent shielding ability. But, It has characteristics emitting characteristic X-rays from the energy area near 30 keV. For patients or radiation workers, shielding materials is often made into contact with the human body. Therefore, the characteristic X-rays generated by the shielding material are directly exposured in the human body, which increases the risk of increasing radiation absorbed dose. In this study, we have developed the FLUKA transport code, one of the most suitable elements of radiation transport codes, to remove the characteristic X-rays generated by barium or iodine. We have verified the reliability of the shielding fraction of the structure of the structure shielding by comparing with the MCPDX simulations conducted as a prior study. Using the MCNPX and FLUKA, the double layer shielding structures with the various thickness combination consisting of barium sulphate ($BaSO_4$) and bismuth oxide($Bi_2O_3$) are designed. The accuracy of the type shown in IEC 61331-1 was geometrically identical to the simulation. In addition, the transmission spectrum and absorbed dose of the shielding material for the successive x-rays of 120 kVp spectra were compared with lead. In results, $0.3mm-BaSO_4/0.3mm-Bi_2O_3$ and $0.1mm-BaSO_4/0.5mm-Bi_2O_3$ structures have been absorbed in both 33 keV and 37 keV characteristic X-rays. In addition, for high-energy X-rays greater than 90 keV, the shielding efficiency was shown close to lead. Also, the transport code of the FLUKA's photon transport code was showed cut-off on low-energy X-rays(below 33keV) and is limited to computerized X-rays of the low-energy X-rays. But, In high-energy areas above 40 keV, the relative error with MCNPX was found to be highly reliable within 6 %.

• International Journal of Highway Engineering
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• v.11 no.3
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• pp.97-109
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• 2009

One of the main causes of asphalt rutting is high temperature of the pavement. Nevertheless, there has been few research on lowering the pavement temperature for reducing rutting. This study investigated the performance characteristics of moisture-retaining porous asphalt pavement, which is known to have a temperature reducing effect. The purpose of this study is to quantify the temperature reducing effect of moisture-retaining porous asphalt pavement and its effect of reducing rutting through Accelerated Pavement Testing(APT). Additionally, the possibility of reducing the thickness of the pavement in comparison to general dense grade pavement by analyzing structural layer coefficient of moisture retaining pavement. A total of three test sections consisting of two moisture-retaining porous asphalt pavement sections and one general dense-grade porous asphalt pavement section were constructed for this study. Heating and spraying of water were carried out in a regular cycle. The loading condition was 8.2 ton of wheel load, the tire pressure of $7.03kgf/cm^2$, and the contact area of $610cm^2$. The result of this experiment revealed that the temperature reducing effect of the pavement was about $6.6{\sim}7.9^{\circ}C$(average of $7.4^{\circ}C$) for the middle layer and $7.9{\sim}9.8^{\circ}C$(average of $8.8^{\circ}C$) for surface course, resulting in a rutting reduction of 26% at the pavement surface. Additionally, the structural layer coefficient of moisture retaining pavement measured from a laboratory test was 0.173, about 1.2 times that of general dense grade pavement. The general dense-grade porous asphalt pavement test section exhibited rutting at all layers of surface course, middle layer, and base layer, while the test sections of moisture-retaining porous asphalt pavement manifested rutting mostly at surface course only.

• Economic and Environmental Geology
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• v.43 no.4
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• pp.417-427
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• 2010

The Lankawi archipelago is located in 30 km western offshore near the Thailand-Malaysia border in west coast of the Malay Peninsula and consists of 99 (+5) tropical islands, covering an area of about $479km^2$. Together with biodiversity in flora and fauna, the Lankawi archipelago displays also geodiversity that includes rock diversity, landform diversity, and fossil diversity. These biodiversity and geodiversity have led to the Lankawi islands as a newly emerging hub for ecotourism in Southeast Asia. As a result, the Lankawi islands have been designated the first Global Geopark in Southeast Asia by UNESCO since July 1st, 2007. The geodiversity of Lankawi Geopark today is a result of a very long depositional history under the various sedimentological regimes and paleoenvironments during the Paleozoic, followed by tectonic and magmatic activities until the early Mesozoic, and finally by surface processes that etched to the present beautiful landscape. Paleozoic strata exposed in the Lankawi Geopark are subdivided into four formations that include the Machinchang (Cambrian), Setul (Ordovician to Early Devonian), Singa (Late Devonian to Carboniferous), and Chuping (Permian) formations in ascending order. These strata are younging to the east, but they are truncated by the Kisap Thrust in the eastern part of the islands. Top-to-the-westward transportation of the Kisap Thrust has brought the older Setul Formation (and possibly Machinchang Formation) from the east to overlay the younger Chuping and Singa formations in the central axis of the Lankawi islands. Triassic Gunung Raya Granite intruded into these sedimentary strata, and turned them partially into various types of contact metamorphic rocks that locally contain tin mineral deposits. Since Triassic, not much geologic records are known for the Lankawi islands. Tropical weathering upon rocks of the Lankawi islands might have taken place since the Early Jurassic and continues until the present. This weathering process played a very important role in producing beautiful landscapes of the Lankawi islands today.