• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.362-362
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• 2014

Atomic layer deposition (ALD) can be regarded as a special variation of the chemical vapor deposition method for reducing film thickness. ALD is based on sequential self-limiting reactions from the gas phase to produce thin films and over-layers in the nanometer scale with perfect conformality and process controllability. These characteristics make ALD an important film deposition technique for nanoelectronics. Tantalum pentoxide ($Ta_2O_5$) has a number of applications in optics and electronics due to its superior properties, such as thermal and chemical stability, high refractive index (>2.0), low absorption in near-UV to IR regions, and high-k. In particular, the dielectric constant of amorphous $Ta_2O_5$ is typically close to 25. Accordingly, $Ta_2O_5$ has been extensively studied in various electronics such as metal oxide semiconductor field-effect transistors (FET), organic FET, dynamic random access memories (RAM), resistance RAM, etc. In this experiment, the variations of chemical and interfacial state during the growth of $Ta_2O_5$ films on the Si substrate by ALD was investigated using in-situ synchrotron radiation photoemission spectroscopy. A newly synthesized liquid precursor $Ta(N^tBu)(dmamp)_2$ Me was used as the metal precursor, with Ar as a purging gas and $H_2O$ as the oxidant source. The core-level spectra of Si 2p, Ta 4f, and O 1s revealed that Ta suboxide and Si dioxide were formed at the initial stages of $Ta_2O_5$ growth. However, the Ta suboxide states almost disappeared as the ALD cycles progressed. Consequently, the $Ta^{5+}$ state, which corresponds with the stoichiometric $Ta_2O_5$, only appeared after 4.0 cycles. Additionally, tantalum silicide was not detected at the interfacial states between $Ta_2O_5$ and Si. The measured valence band offset value between $Ta_2O_5$ and the Si substrate was 3.08 eV after 2.5 cycles.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.293-293
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• 2014

Over last decade InGaN alloy structures have become the one of the most promising materials among the numerous compound semiconductors for high efficiency light sources because of their direct band-gap and a wide spectral region (ultraviolet to infrared). The primary cause for the high quantum efficiency of the InGaN alloy in spite of high threading dislocation density caused by lattice misfit between GaN and sapphire substrate and severe built-in electric field of a few MV/cm due to the spontaneous and piezoelectric polarizations is generally known as the strong exciton localization trapped by lattice-parameter-scale In-N clusters in the random InGaN alloy. Nonetheless, violet-emitting (390 nm) conventional low-In-content InGaN/GaN multi-quantum wells (MQWs) show the degradation in internal quantum efficiency compared to blue-emitting (450 nm) MQWs owing higher In-content due to the less localization of carrier and the smaller band offset. We expected that an improvement of internal quantum efficiency in the violet region can be achieved by replacing the conventional low-In-content InGaN/GaN MQWs with ultra-thin, high-In-content (UTHI) InGaN/GaN MQWs because of better localization of carriers and smaller quantum-confined Stark effect (QCSE). We successfully obtain the UTHI InGaN/GaN MQWs grown via employing the GI technique by using the metal-organic chemical vapor deposition. In this work, 1 the optical and structural properties of the violet-light-emitting UTHI InGaN/GaN MQWs grown by employing the GI technique in comparison with conventional low-In-content InGaN/GaN MQWs were investigated. Stronger localization of carriers and smaller QCSE were observed in UTHI MQWs as a result of enlarged potential fluctuation and thinner QW thickness compared to those in conventional low-In-content MQWs. We hope that these strong carrier localization and reduced QCSE can turn the UTHI InGaN/GaN MQWs into an attractive candidate for high efficient violet emitter. Detailed structural and optical characteristics of UTHI InGaN/GaN MQWs compared to the conventional InGaN/GaN MQWs will be given.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6595-6603
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• 2015

This study analyzes the moderating effects of the self-esteem on the life satisfaction of 2,040 middle school senior students using the Korean Children and Youth Panel Survey 2012 Data (KCYPS 2012) provided by the National Youth Policy Institute. The path analysis of how environmental characteristics, such as parents, friends, and school, affect life satisfaction, is based on four groups of self-esteem, categorized by positive and negative self-evaluation levels. The analysis suggests that groups with higher levels of positive self-evaluation have closer relevance in more paths than other groups. Furthermore, in groups with higher levels of negative self-evaluation, negative effects on life satisfaction are offset by positive self-evaluation. These results suggest research associated with the mental health of adolescents and their self-esteem should be performed according to two separate levels of self-esteem: positive self-evaluation and negative self-evaluation. Since low levels of negative self-evaluation doesn't necessarily guarantee high levels of positive self-evaluation, counseling for adolescents needs to have different tracks, addressing positive and negative self-evaluation levels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.301-309
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• 2020

Defense exports have overgrown in a short period, and items have been diversified with advanced high-end equipment, but exports have been stagnant due to the global economic recession and fierce competition. Weapons importers in the global market are diversified, volatility is higher, and global defense companies are also expanding their global value chain (GVC) By participating in the GVC of a global defense company, the defense SME can grow into a competitive company with specialized technology, rather than participating as a partner of a domestic system company. It is time to prepare an export promotion support plan. In this study, we selected five global companies with high value for the implementation of offset and general considerations on domestic SMEs' entry into the international parts supply chain and related cases, and investigated GVC entry requirements, the current status of cooperation partners, and the perceptions of GVC entry, through local surveys in Korea and overseas. Also, by considering the export target comprehensively, GVC stage, and the level of export competitiveness of domestic SMEs, strategies for promoting GVC participation of defense SMEs and improvements in government policies were derived and presented.

• Ocean and Polar Research
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• v.39 no.2
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• pp.85-106
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• 2017

The Lago Sofia conglomerate in southern Chile is a deep-marine gravelly deposit, which is hundreds of meters thick and kilometers wide and extends laterally for more than 100 km, filling the foredeep trough of the Cretaceous Magallanes Basin. For understanding the depositional processes and environments of this gigantic deep-sea conglomerate, detailed analyses on sedimentary facies, architecture and paleoflow patterns were carried out, highlighting the differences between the northern (Lago Pehoe and Lago Goic areas) and southern (Lago Sofia area) parts of the study area. The conglomerate bodies in the northern part occur as relatively thin (< 100 m thick), multiple units intervened by thick mudstone-dominated sequences. They show paleoflows toward ENE and S to SW, displaying a converging drainage pattern. In the southern part, the conglomerate bodies are vertically interconnected and form a thick (> 400 m thick) conglomerate sequence with rare intervening fine-grained deposits. Paleoflows are toward SW. The north-to-south variations are also distinct in sedimentary facies. The conglomerate bodies in the southern part are mainly composed of clast-supported conglomerate with sandy matrix, which is interpreted to be deposited from highly concentrated bedload layers under turbidity currents. Those in the northern part are dominated by matrix- to clast-supported conglomerate with muddy matrix, which is interpreted as the products of composite mass flows comprising a turbidity current, a gravelly hyperconcentrated flow and a mud-rich debris flow. All these characteristics suggest that the Lago Sofia conglomerate was formed in centripetally converging submarine channels, not in centrifugally diverging channels of submarine fans. The tributaries in the north were dominated by mass flows, probably affected by channel-bank failures or basin-marginal slope instability processes. In contrast, the trunk channel in the south was mostly filled by tractive processes, which resulted in the vertical and lateral accretion of gravel bars, deposition of gravel dunes and filling of scours and channels, similar to deposits of terrestrial gravel-bed rivers. The trunk channel developed along the axis of foredeep trough and its confinement within the trough is probably responsible for the thick, interconnected channel fills. The large-scale architecture of the trunk-channel fills shows an eastward offset stacking pattern, suggesting that the channel migrated eastwards most likely due to the uplift of the Andean Cordillera.

• The Korean Journal of Financial Management
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• v.26 no.1
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• pp.65-94
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• 2009

The event of change in KOSPI 200 Index composition is one of the main subjects for the test of EMH. According to EMH, when a certain event is not related with firm's fundamental value, stock price should not change after the announcement of news. This hypothesis leads us to the conclusion of horizontal demand curve of stock. This logic was questioned by Shleifer(1986) and argued that downward sloping demand curve hypothesis was supported. But Harris and Gruel(1986) found a different empirical evidence that price reversal occurs in the long run, which is called price pressure hypothesis. They argued that short term price effect by large block trading (price pressure) is offset in the long run because these event is unrelated to fundamental value. Therefor, they argued that EMH can not be rejected in the long run. Until now, there are two empirical studies with Korean market data in this area. Using a data with same time period of $1996{\sim}1999$, Kweon and Park(2000) and Ahn and Park(2005) showed that stock price or beta is not significantly affected by change in index composition. This study retested this event expanding sample period from 1996 to 2006, and analyzed why this event was considered an uninformative events in the preceding studies. We analyzed a market impact by separating samples according to firm size and market condition. In case of newly enlisted firm, we found the evidence supporting price pressure hypothesis on average. However, we found the long run price effect in the sample of large firms under bearish markets. At the same time, we know that the number of samples under the category of large firms under bearish markets is relatively small, which drives the same result of supporting the hypothesis that change in index composition is a non-informative event on average. Also, the long run price effect of large size firms under bearish markets was supported by the analyses using trading volumes. On the other hand, in case of delisting from the index, we found the long run price effect but that was not supported by trading volume analyses.

• Environmental and Resource Economics Review
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• v.14 no.1
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• pp.135-166
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• 2005

This paper measures integrated pollution intensities and changes in pollution intensity, and figure out environmental performance. We introduce a new definition of pollution intensity and its method measuring integrated pollution intensities. We distinguish 24 manufacturing industries into light industry and heavy industry, and divide heavy industry into pollution industry and the other residual heavy industry to measure the integrated pollution intensities and their changes. While the pollution industry within heavy industry, based on the integrated pollution intensity, was the most pollution-intensive, the other residual heavy industry within the heavy industry was the most successive in reducing pollutants. The annualized average index of the integrated pollution intensities grew as much as 9.1 percent, of which the annualized change in the index of pollution emission increased 13.3 percent, but the improvement of 3.9 percent in the change of output quantity offset the increase in the index of pollution emission. The changes in the integrated pollution intensity for the light and heavy industries were 1.125 and 1.042, respectively. The reason the heavy industry showed the lower change in the index of pollution intensity, while the change in the pollution industry was very high, was because the average change in the other heavy industry decreased around 9 percent.

• Environmental and Resource Economics Review
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• v.24 no.4
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• pp.747-761
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• 2015

This paper investigates the impact of an increase in unit price of solid waste collection on demand for alternative solid waste disposal types. I control for other variables affecting the demand and employ both community and time fixed effects models in the estimation of each reduced-form demand functions. Estimation results show that an increase in unit price reduces the demand for garbage bag collection services of non-food solid wastes while it increases the demand for food wastes and source-separated recyclables. These results imply that reduction in the demand for non-food solid wastes collection is mainly achieved by increasing the amount of recyclables and food wastes collected. However, it appears that an increase in unit price increases the total amount of solid wastes generated. This suggests that price incentive effects are offset by the decrease in source-reduction efforts because of feedback effects resulting from the increase in recycling, food waste separation, and illegal disposal of wastes.

• The Journal of the Korea Contents Association
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• v.15 no.12
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• pp.483-492
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• 2015

This study involved elementary schoolchildren in Busan Metropolitan city and assumed the foundation of social cooperative associations that provide education services for meteorological fields, then we analyzed expected profits in a year for successful operation of first year. Twelve variables relating to profits and expenses were derived, and we used the decision tree for analyzing optimal expected profits. Profit-related variables were lecture's fee per hour and price of textbooks. Expense-related variables were production costs for the textbooks, annual salary for a teacher, education costs for a teacher, developing costs for the textbooks, traveling expenses, rental fees, and operating costs. Besides, by adding education demands, the number of grades, and the number of teachers, we analyzed changes in expected profits, considering variability of profits and expenses. As a result, despite of expected lower demands, to increase price of textbooks and education costs per hour was of advantage to enhance expected profits. The reason is that the more demand, the more increased production costs for textbooks, which is because not to make enough profits to offset the increased expenses due to lowered price of textbooks and education costs. Considering the value of public interest for social cooperative associations, price determination only concerning increase in demands will be avoided.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.325-337
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• 2014

To assess the functional structure of prepro-melanin-concentrating hormone (pMCH), we isolated and cloned pMCH (of-pMCH) mRNA from the brain of the olive flounder, Paralichthys olivaceus, and compared its amino acid sequence with those from other animals. In addition, to examine whether activation of the brain of-pMCH gene is influenced by background color, density, and feeding, we compared pMCH mRNA activities against different background colors (bright and dark) and at different densities (100% PCA and 200% PCA). To examine whether the pMCH gene is related with malpigmentation of blind-side skin and appetite, we compared pMCH gene expression between ordinary and hypermelanic flounders, and between feeding and fasting flounders. The of-pMCH cDNA was 405 bp in the open reading frame [ORF] and encoded a protein of 135 amino acids; MCH was 51 bp in length and encoded a protein of 17 amino acids. An obvious single band of the expected size was obtained from the brain and pituitary by RT-PCR. In addition, of-pMCH gene activity was significantly higher in the bright background only at low density (< 100% PCA) making the ocular skin of fish whitening, and in ordinary fish. However, the gene activity was significantly decreased in dark background, at high density (>200% PCA), and in hypermelano fish. These results suggest that skin whitening camouflage of the flounder is induced by high MCH gene activity, and the density disturbs the function of background color in the physiological color change. Moreover, our data suggest that a low level of MCH gene activity may be related to malpigmentation of the blind-side skin. In feeding, although pMCH gene activity was significantly increased by feeding in the white background, the pMCH gene activity in the dark background was not influenced by feeding, indicating that the MCH gene activity increased by feeding can be offset by dark background color, or is unaffected by appetite. In conclusion, this study showed that MCH gene expression is related to ocular-skin whitening camouflage and blind-skin hypermelanosis, and is influenced by background color and density.