• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.28-46
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• 2001

Natural gas is a mixture of hydrocarbon gases and impurities such as nitrogen, hydrogen sulfide, and carbon dioxide and a clean energy producing no pollution materials for combustion. Currently, the demand of the natural gas is rapidly increasing due to worldwide environmental problems. According to Hubbert's study in the past, the natural gas was predicted as rapidly depleted resources, and then the results led to high gas price and limitation of usage during 1980s. Afterward, the study of natural gas resources based on geology identified the additional natural gas resources that were not considered in Hubbert's study. They are unconventional gas, additional resources in the existed reservoirs, and natural gas in deep subsurface areas. Such additional resouces made the future of natural gas bright and pormised low and stable gas price in the future. Deep natural gas is defined as the gas existing at or below 15,000ft$(4,752{\cal}m)$ in depth from the surface. According to the study from the U.S. Geological Survey(USGS) in 1995, 1,412 TCF of technically recoverable natural gas was remained to be discovered or developed in the onshore of United States. A significant part of that resource base, 114 TCF, exists at deep sedimentary basins, and it shows wide distribution with various geological environments. In 1995, the deep gas contributed to $6.7\% of total supply amount of natural gas in the United States and is expected to be $18.7\% by 201.5. However, the development of the deep gas is a high risky business due to expensive investment and high portion of dry holes, although it is developed. Thus, for developing the deep gas economically, it is necessary to overcome many technical challenges. In this paper, for increasing success rate of the deep gas, 1) geologic and compositional characteristics, and production cost have been analyzed according to depth, 2) technical problems related to deep gas production have been summarized, and 3) finally future study areas for increasing application of the deep gas have been suggested. For reference, this paper was written based on the study results from USGS and Gas Research Institute(GRI), for the United States is doing the most active R&D in the deep gas area, and thus, has many reliable data.

• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.91-100
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• 2006

In this study, changes of ammonia, alcohol and volatile fatty acid(VFA) concentrations or pH in in vitro ruminal fluid were studied to determine the effects of alcoholic feeds on in vitro ruminal fermentation characteristics. To formulate the alcoholic feeds, alcohol was added to commercial formulated feed at the levels of 1, 3, and 5 %. Experiments were done with four treatment groups, control(commercial feed), AF-1(commercial feed+1% alcohol), AF-3(commercial feed+3% alcohol), and AF-5(commercial feed+5% alcohol). Ammonia concentrations of AF-1 and AF-5 were significantly lower than that of control for the 12h incubation(p<0.05). Ruminal alcohol concentration was increased with the addition level of alcohol increased(p<0.05). TVFA concentrations of AF-1, AF-3 and AF-5 were significantly higher than those of control at 12h(p<0.05). Significant decrease of molar percentage of acetate was observed in control from 8 to 12h incubation, but molar percentage of acetate for AF-1, AF-3 and AF-5 was constant. Molar percentage of propionate was increased in control compared with AF-1, AF-3 and AF-5 from 8 to 12h incubation(p<0.05). Molar percentages of butyrate and valerate were higher in AF-1, AF-3 and AF-5 than in control(p<0.05). Molar percentage of caproate for AF-1, AF-3 and AF-5 was 0.05, 0.58 and 0.47M% at 8h, respectively, but that was not detected for control. Present results may indicate that the alcoholic feeds show positive effects on in vitro ruminal ammonia, alcohol and VFA concentrations or pH. Furthermore, the results of this study implies that the addition level of 5% could be more effective to ruminal fermentation than other addition levels.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.273-286
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• 2008

Road-map for the environmental friendly integrated pest management(IPM) of insect pests was drawn up on the strawberry vinyl-houses of farmer's field. Major insect pests were occurred Tetranychus urticae and Aphis gossypii during the strawberry plant seeding in the vinyl house and open field. Also, same insect pests were occurred in the vinyl house during harvesting season of strawberry. For the control of T. urticae and A. gossypii, Phytoseiulus persimilis and Aphidius colemani as natural enemies were input to the vinyl house, respectively. However, because these natural enemies could not control insect pest populations, acaricide and insecticide were sprayed. Then natural enemies were input again in the vinyl house. Natural enemies could not endure the intense cold and differences of temperature and relative humidity between day and night during strawberry harvesting season. So, their behavior and control activity of pests were more decrease than pests. Firstly, natural enemies are input in the vinyl house during the early breeding season of strawberry, secondly, acaricides and insecticide are sprayed for the control of mites and aphids, respectively, during the middle breeding season in the hard winter. Finally, natural enemies are re-input in the vinyl house during the middle and late breeding season.

• The Journal of Information Systems
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• v.24 no.2
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• pp.23-52
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• 2015

Purpose This study aims to understand the role of digital knowledge in accepting the green technology. This study combined digital option theory with the second version of the Unified Theory of Acceptance and Use of Technology (UTAUT2). Contrary to other studies in which the UTAUT2 is used to explain IT adoption behavior, we look at the relationship between IT and the UTAUT2 from a new angle, incorporating an important aspect of IT, that is, digitized knowledge richness, as a determinant of the UTAUT2. Design/methodology/approach Grounded in the UTAUT2, a content analysis was conducted to investigate novel constructs dedicated to explaining green technology adoption. In this study, an amended version of the UTAUT2 specific to green technology is offered that better explains the green technology adoption behavior of consumers. Using the items identified by content analysis, we developed a questionnaire with 36 survey items. We measured all the items on a seven-point Likert-type scale. We randomly selected 402 survey respondents from a set of panel data. After a pilot study, we analyzed the main survey data by using PLS 2.0M3 and SPSS 20.0, and employed structural equation modeling to test the hypotheses. Findings The results suggest that the UTAUT2 was found to be extendable to technologies other than conventional IT. Social influence is more significant than conventional utilitarian and hedonic-based constructs such as those utilized in the UTAUT and UTAUT2 in explaining adoption behavior in the context of green technologies. The hypothesized connection between digitized knowledge richness and adoption intention was supported by the results of studies on the role of IT in formation of attitudes toward eco-friendly production. The results also indicate that digital knowledge can also encourage people to try green technology when they learn that their peers are already using the technology successfully.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1566-1573
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• 2006

The study was conducted on 30 true acyclic Sahiwal cows (15 cows, ${\geq}90$ days postpartum; 15 postpubertal heifers, ${\geq}30$ months of age) and a similar 20 untreated controls (10 cows, 10 heifers). An 'Eazi' breed Controlled Internal Drug Release (CIDR) device (containing 1.38 g progesterone) was inserted intravaginally for 7 days (days 0 to 7) followed by 500 IU eCG i.m. at CIDR removal in all the treated animals. Heifers also received 5 mg oestradiol valerate i.m at CIDR insertion. The reproductive performance of these animals was recorded in terms of oestrus induction response, conception and pregnancy rates. Plasma progesterone ($P_4$) and oestradiol-$17{\beta}$ ($E_2$) profiles of 4 representative animals from each treatment group before, during and after CIDR treatment were also monitored. An oestrus induction response of 100% was observed in treated cows and heifers. The majority of cows (53.3%) and heifers (60%) were induced to oestrus within 24-36 and 36-48 h, respectively after CIDR withdrawal; with mean intervals of $44{\pm}3.18$ and $48{\pm}2.35h$, respectively. The conception rate at induced oestrus was higher in cows (40%) than heifers (20%). The final pregnancy rates after 2 subsequent oestruses were 80 and 60% in cows and heifers, respectively (overall 70% for all treated animals). In comparison, only 10% of control animals (2 cows only, 2/20) showed oestrus and become pregnant (10%) during theentire study period. The pretreatment (day 0) mean plasma P4 levels were statistically (p>0.05) similar in cows and heifers ($0.40{\pm}0.04$ and $0.49{\pm}0.11ng/ml$, respectively). The peak $P_4$ levels were observed on day 1 in cows ($13.94{\pm}1.41ng/ml$) and day 2 in heifers ($19.15{\pm}3.30ng/ml$) with a progressive decline up to the day of CIDR withdrawal ($3.35{\pm}0.92$ and $8.79{\pm}1.71ng/ml$, respectively). Mean $P_4$ levels on day 9 and 10 in cows and heifers did not differ significantly from their respective day 0 values and the lowest values were recorded on day 10 both in cows and heifers ($0.13{\pm}0.03$ and $0.14{\pm}0.02ng/ml$, respectively). Wide variations in individual pretreatment $E_2$ levels were observed both in the cows (range = 4-26, mean = $13.00{\pm}4.65pg/ml$) and heifers (range = 10-14, mean = $11.50{\pm}0.96pg/ml$). Thereafter also, $E_2$ levels in cows showed variation and reached a peak level ($53.50{\pm}2.99pg/ml$) on day 8. In heifers, peak mean $E_2$ level ($111.25{\pm}39.81pg/ml$) was recorded on day 1, followed by a non-significant decline on day 2, a significant fall on day 6 and a non-significant increase on day 9 and 10. However, mean $E_2$ levels on days 7 (p<0.05), 8 and 9 (p<0.01) were significantly higher in cows compared to heifers. The post-CIDR withdrawal mean highest $P_4$ and lowest $E_2$ levels coincided with the period when the majority of animals were induced to oestrus. CIDR and eCG treatment resulted in effective induction of oestrus with satisfactory pregnancy rates in true acyclic Sahiwal cows and heifers.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.633-638
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• 2011

Mn substituted La, Sr or Ba-hexaaluminate were prepared by $(NH_4)_2CO_3$ co-precipitate method and calcined at $1,200^{\circ}C$ for 5 h. Catalysts were characterized by X-ray diffraction and $N_2$ physisorption and scanning electron microscope (SEM). Compared to $SrMnAl_{11}O_{19}$ and $BaMnAl_{11}O_{19}$, $LaMnAl_{11}O_{19}$ in which La located at mirror plane showed better crystallinity and high surface area, 13 $m^2/g$. $LaMnAl_{11}O_{19}$ revealed well developed plate-like structure which is characteristic structure of hexaaluminate. The catalytic activity of methane combustion increased in the following order: $LaMnAl_{11}O_{19}$ > $SrMnAl_{11}O_{19}$ > $BaMnAl_{11}O_{19}$ and was dependent on surface area of catalysts. 60 wt% $CeO_2/LaMnAl_{11}O_{19}$ calcined at $700^{\circ}C$ showed enhanced methane activity and methane was oxidized completely at low temperature ($700^{\circ}C$). It was confirmed that addition of ceria seems to be effective for the low and middle temperature combustion of methane. But, after calcination at high temperature of $1,200^{\circ}C$, it lost the promoting effect of ceria due to increase of ceria particle size and it had a limit to applying to the high temperature catalytic combustion.

• The Korean Journal of Quaternary Research
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• v.16 no.2
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• pp.9-21
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• 2002

In Korea, many open-air upper palaeolithic sites are located at the river valley, particularly exposed in gently rotting terrain along the river course. They are situated at an altitude less trail 30 m above present river bottom, and covered with the blankets of slope deposits of several meters in thickness. The purpose of this research is to eluridate depositional and vegetational environment of the alluvial upper palaeolithic Jangheung-ri sites on the basis of analytical properties of grain size population, chronology, palynology, soil chemistry and clay mineralogy and magnetic susceptibility of the Jangheung-ri Quaternary formations. The lithostratograpy of Jangheung-ri sit is subdivided into 3 layers based on the depositional sequence and radiocarbon ages. From bottom to top, they are composed of slope deposits with lower paleosol layers, young fluvial sand and gravel with backswamp organic muds, and upper paleosol layers. The upper paleosol was formed under rather dry climatic condition between each flooding period. Dessication cracks were prevalent in the soil solum which was filled with secondarily minuted fragments due to pedogenetic process. The soil structure shows typical braided-typed cracks in the root part of cracking texture, and more diversified pattern of crackings downward. The young fluvial sand gravel were formed by rather perennial streams after LGM. The main part of organic muds was particularly formed after 15Ka. Local backswamp were flourished with organic muds and graded suspension materials in the flooding muds were intermittently accumulated in the organic muds until ca. 11Ka. This episode was associated with migration of Nam River toward present course. Organic muds were formed in backswamp or local pond. Abies/Picea-Betula with Ranunculaceae, Compositae, Cyperaceae were prevalent. This period is characterized with B$\Phi$lling, Older Dryas, Allerod, and Younger Dryas (MIS-1). Stone artefacts were found in the lower paleosol layers formed as old as 18Ka-22Ka. Based on the artefacts and landscape settings of the Jangheung-ri site, it is presumed that settlement grounds of old people were buried by frequent floodings of old Nam River, the river-beds of which were heavily fluctuated laterally and river-bed erosions were activated from south to north in Jangheung-ri site until the terminal of LGM9ca 17Ka).

• Childhood Kidney Diseases
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• v.2 no.1
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• pp.14-19
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• 1998

Purpose : Hypocalcemia is one of the major causes of convulsion in infants. The causes of hypocalcemia are hypoparathyroidism, deficiency and metabolic abnormalities of vitamin D, or increased uptake of inorganic phosphorous, etc. We analyzed the causes, symptoms and signs, treatment, and clinical courses of hypocalcemia as, recently, there were many clinical experiences of hypocalcemic infants under age of 6 months in the department of pediatrics, Kyungpook University Hospital. Objects and Methods : The authors observed 11 infants with hypocalcemia who had been admitted to the department of pediatrics, Kyungpook University Hospital, during the period of February 1992 to April 1997. Various clinical and laboratory data concerning causes, clinical courses and treatment of hypocalcemia were analyzed retrospectively Results : (1) The sex incidence revealed male predominance with male to female ratio 4.5 : 1. The mean age at onset of symptoms was $2.2{\pm}1.1$ months old. (2) The causes of hypocalcemia were vitamin D deficiency in 8 cases and excessive inorganic phosphate intake in 3 cases. (3) All eleven patients manifestated convulsion which was generalized tonic-clonic in 9, and focal clonic in 2 cases. (4) Serum calcium concentrarion increased from $6.3{\pm}0.9$ mg/dL to $9.9{\pm}1.7$ mg/dL after therapy of $1,25(OH)_{2}D_{3}$ with or without calcium(P=0.0008), and serum ALP concentration decreased from $1,418{\pm}864$ U/L to $772{\pm}503$ U/L (P=0.0112). Serum iPTH levels were high in all 11 patients initially. All showed decreased $25(OH)D_3$ levels initially. (5) All patients were treated successfully with $1,25(OH)_{2}D_{3}$ and/or calcium supplement. Conclusions : Vitamin D deficiency should be considered as one of the causes of hypocalcemia even in formula(known as vitamin fortified) feeding infants. Fortunately, they were successfully treated with $1,25(OH)_{2}D_{3}$.

• The korean journal of orthodontics
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• v.35 no.1 s.108
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• pp.60-68
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• 2005

The evaluation of malocclusion has to be done quantitatively and qualitatively. This will be lead toward an analysis of malocclusion severity as well as treatment difficulty. The method of proper evaluation of malocclusion severity and treatment difficulty is necessary to assess treatment effect and efficiency for the orthodontists and to establish fundamentals for planning and executing the health-related policies in private and public institutions. The purposes of this study as the first part of the objective and quantitative analysis of malocclusion were 1) to measure treatment difficulty based on the opinions of several orthodontists. and 2) to investigate the relationships between objective malocclusion severity and subjective treatment difficulty 100 pairs of dental casts that had various types and severity of malocclusion were selected from the orthodontic departments of Kyurghee University and Samsung Medical Center The objective malocclusion severity was measured with the PAR (Peer Assessment Rating) index and the subjective treatment difficulty was evaluated by 8 experienced orthodontists. The relationships between objective malocclusion severity and subjective treatment difficulty were statistically evaluated. There were significant relationships between objective malocclusion severity and subjective treatment difficulty especially in the measurements of the upper anterior alignment, the buccal occlusion. the overjet, the overbite and the midline discrepancy en the malocclusion components. The results of this study can provide the background knowledge to develop a new occlusal index. which contains both the malocclusion severity and treatment difficulty for Korean orthodontists.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.365-376
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• 1999

The importance of finishing and polishing the restoration has been described by several authors. The final step provides for improved metallurgical properties, better marginal adaptation, reduced plaque accumulation. Unfortunately, finishing of the restorations can produce damage from temperature rises at the pulpal wall. The aim of this study was to determine the changes in temperature can be occurred during the use of finishing and polishing instruments under a variety of conditions. ; with or without a water coolant, intermittent or continuous operation, high or low rotation speed, remaining dentin thickness and various restorative materials. Class V preparations were cut on extracted molars and restored with composite resin(Z 100), resin-modified glass ionomer cements(Dyract, Fuji II LC), and amalgam. Finishing was done with aluminum oxide coated disc($Sof-lex^{(R)}$ polishing disc, 3M, USA). The following results were obtained. 1. The rise of temperature during polishing of amalgam restorations was the highest among the all experimental groups except polishing with water coolant(P<0.05). However, there were no statistical differences in temperature rises between Z 100, Dyract and Fuji II LC(P>0.05). 2. The intrapulpal temperature was greatly influenced by the applied time, and intermittent polishing was showed significantly lower temperature rises than continuous polishing(P<0.01). 3. The intrapulpal temperature was increased according to the application of polishing regard less of using water coolant. However, polishing with water coolant showed significantly lower temperature in the pulp than not used water coolant(P<0.01).