• Title/Summary/Keyword: surface states

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Observational Characteristics of East Asian Monsoon during the Summers of 1993 and 1994 (1993, 1994년 여름철 동아시아몬순의 관측 특성)

  • Kim, Baek-Jo;Ryu, Chan-Su
    • Journal of the Korean earth science society
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    • v.23 no.4
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    • pp.369-379
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    • 2002
  • The characteristics of the East Asian summer monsoon circulation associated with the cool and wet summer of 1993 and the warm and dry summer of 1994 are investigated by analyzing the atmospheric circulations features in the upper and lower troposphere and by examining the global SST and associated tropical convective precipitation fields. The negative geopotential height anomalies at 500 hPa and 200 hPa in 1993 over East Asia, the central North Pacific, and the western United States were replaced by positive ones in 1994. In addition, the 200 hPa zonal wind anomaly averaged over the East Asian summer monsoon region is negatively correlated with the Korean summer temperature anomaly. The subtropical jet stream in 1993 was displaced into the central part of Korea well south of its normal position. The western Pacific subtropical high was shifted southward, and the East Asian summer rainfall and temperature was above-normal and below-normal, respectively due to the southwestward extension of a cold and dry polar airmass from the Sea of Okhotsk to the Est Sea. In contrast, the subtropical jet stream in 1994 was displaced well north of its normal position. The abrupt northward shift of the western Pacific subtropical high was accompanied with the rapid northward movement of the rain band of the East Asian summer monsoon rainfall. The anomaly patterns of the East Asia summer rainfall and temperature were opposite to those of 1993. Large sea surface temperature anomalies of opposite signs existed in the tropical Pacific with a mature El $Ni{\~{n}o$ in 1993 and a weak La $Ni{\~{n}a$ condition in 1994. The role of the anomalous convective precipitation in the western Pacific and the Indian Ocean related with the variations in the low-level cross-equatorial flow along the northwestern periphery of the Australian high and the Mascarene high is probably to influence a large-scale atmospheric circulation over the East Asia during both the years.

Ordinary Magnetoresistance of an Individual Single-crystalline Bi Nanowire (자발 성장법으로 성장된 단결정 Bi 단일 나노선의 정상 자기 저항 특성)

  • Shim, Woo-Young;Kim, Do-Hun;Lee, Kyoung-Il;Jeon, Kye-Jin;Lee, Woo-Young;Chang, Joon-Yeon;Han, Suk-Hee;Jeung, Won-Young;Johnson, Mark
    • Journal of the Korean Magnetics Society
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    • v.17 no.4
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    • pp.166-171
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    • 2007
  • We report the magneto-transport properties of an individual single crystalline Bi nanowire grown by a spontaneous growth method. We have successfully fabricated a four-terminal device based on an individual 400-nm-diameter nanowire using plasma etching technique to remove an oxide layer forming on the outer surface of the nanowire. The transverse MR (2496% at 110 K) and longitudinal MR ratios (38% at 2 K) for the Bi nanowire were found to be the largest known values in Bi nanowires. This result demonstrates that the Bi nanowires grown by the spontaneous growth method are the highest-quality single crystalline in the literatures ever reported. We find that temperature dependence of Fermi energy ($E_F$) and band overlap (${\triangle}_0$) leads to the imbalance between electron concentration ($n_e$) and hole concentration ($n_h$) in the Bi nanowire, which is good agreement with the calculated $n_e\;and\;n_h$ from the respective density of states, N(E), for electrons and holes. We also find that the imbalance of $n_e\;and\;n_h$ plays a crucial role in determining magnetoresistance (MR) at T<75 K for $R_T$ and at T<205 K for $R_L$, while mean-free path is responsible for MR at T>75 K for $R_T$ and T>205 K for $R_L$.

The Characteristics of the Wafer Bonding between InP Wafers and $\textrm{Si}_3\textrm{N}_4$/InP (Direct Wafer Bonding법에 의한 InP 기판과 $\textrm{Si}_3\textrm{N}_4$/InP의 접합특성)

  • Kim, Seon-Un;Sin, Dong-Seok;Lee, Jeong-Yong;Choe, In-Hun
    • Korean Journal of Materials Research
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    • v.8 no.10
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    • pp.890-897
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    • 1998
  • The direct wafer bonding between n-InP(001) wafer and the ${Si}_3N_4$(200 nm) film grown on the InP wafer by PECVD method was investigated. The surface states of InP wafer and ${Si}_3N_4$/InP which strongly depend upon the direct wafer bonding strength between them when they are brought into contact, were characterized by the contact angle measurement technique and atomic force microscopy. When InP wafer was etched by $50{\%}$ HF, contact angle was $5^{\circ}$ and RMS roughness was $1.54{\AA}$. When ${Si}_3N_4$ was etched by ammonia solution, RMS roughness was $3.11{\AA}$. The considerable amount of initial bonding strength between InP wafer and ${Si}_3N_4$/InP was observed when the two wafer was contacted after the etching process by $50{\%}$ HF and ammonia solution respectively. The bonded specimen was heat treated in $H^2$ or $N^2$, ambient at the temperature of $580^{\circ}C$-$680^{\circ}C$ for lhr. The bonding state was confirmed by SAT(Scannig Acoustic Tomography). The bonding strength was measured by shear force measurement of ${Si}_3N_4$/InP to InP wafer increased up to the same level of PECVD interface. The direct wafer bonding interface and ${Si}_3N_4$/InP PECVD interface were chracterized by TEM and AES.

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Direct Bonding of SillSiO2/Si3N4llSi Wafer Fairs with a Fast Linear Annealing (선형가열기를 이용한 SillSiO2/Si3N4llSi 이종기판쌍의 직접접합)

  • 이상현;이상돈;송오성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.4
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    • pp.301-307
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    • 2002
  • Direct bonded SOI wafer pairs with $Si ll SiO_2/Si_3N_4 ll Si$ the heterogeneous insulating layers of SiO$_2$-Si$_3$N$_4$are able to apply to the micropumps and MEMS applications. Direct bonding should be executed at low temperature to avoid the warpage of the wafer pairs and inter-diffusion of materials at the interface. 10 cm diameter 2000 ${\AA}-SiO_2/Si(100}$ and 560 $\AA$- ${\AA}-Si_3N_4/Si(100}$ wafers were prepared, and wet cleaned to activate the surface as hydrophilic and hydrophobic states, respectively. Cleaned wafers were pre- mated with facing the mirror planes by a specially designed aligner in class-100 clean room immediately. We employed a heat treatment equipment so called fast linear annealing(FLA) with a halogen lamp to enhance the bonding of pre mated wafers We kept the scan velocity of 0.08 mm/sec, which implied bonding process time of 125 sec/wafer pairs, by varying the heat input at the range of 320~550 W. We measured the bonding area by using the infrared camera and the bonding strength by the razor blade clack opening method, respective1y. It was confirmed that the bonding area was between 80% and to 95% as FLA heat input increased. The bonding strength became the equal of $1000^{\circ}C$ heat treated $Si ll SiO_2/Si_3N_4 ll Si$ pair by an electric furnace. Bonding strength increased to 2500 mJ/$\textrm{m}^2$as heat input increased, which is identical value of annealing at $1000^{\circ}C$-2 hr with an electric furnace. Our results implies that we obtained the enough bonding strength using the FLA, in less process time of 125 seconds and at lowed annealing temperature of $400^{\circ}C$, comparing with the conventional electric furnace annealing.

Ridge and field tile aerodynamics for a low-rise building: a full-scale study

  • Tecle, Amanuel;Bitsuamlak, Girma T.;Suskawang, Nakin;Chowdury, Arindam Gan;Fuez, Serge
    • Wind and Structures
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    • v.16 no.4
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    • pp.301-322
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    • 2013
  • Recent major post-hurricane damage assessments in the United States have reported that the most common damages result from the loss of building roof coverings and subsequent wind driven rain intrusion. In an effort to look further into this problem, this paper presents a full-scale (Wall of Wind --WoW--) investigation of external and underneath wind pressures on roof tiles installed on a low-rise building model with various gable roofs. The optimal dimensions for the low-rise building that was tested with the WOW are 2.74 m (9 ft) long, 2.13 m (7 ft) wide, and 2.13 m (7 ft) high. The building is tested with interchangeable gable roofs at three different slopes (2:12; 5:12 and 7:12). The field tiles of these gable roofs are considered with three different tile profiles namely high (HP), medium (MP), and low profiles (LP) in accordance with Florida practice. For the ridge, two different types namely rounded and three-sided tiles were considered. The effect of weather block on the "underneath" pressure that develops between the tiles and the roof deck was also examined. These tests revealed the following: high pressure coefficients for the ridge tile compared to the field tiles, including those located at the corners; considerably higher pressure on the gable end ridge tiles compared to ridge tiles at the middle of the ridge line; and marginally higher pressure on barrel type tiles compared to the three-sided ridge tiles. The weather blocking of clay tiles, while useful in preventing water intrusion, it doesn't have significant effect on the wind loads of the field tiles. The case with weather blocking produces positive mean underneath pressure on the field tiles on the windward side thus reducing the net pressures on the windward surface of the roof. On the leeward side, reductions in net pressure to a non-significant level were observed due to the opposite direction of the internal and external pressures. The effect of the weather blocking on the external pressure on the ridge tile was negligible.

A study on morphological and pattern analysis in two kinds of Aconiti Radix (부자(附子)와 초오(草烏)의 내외부형태(內外部形態)와 패턴분석연구)

  • Kang, Gyun-Heok;Choi, Go-Ya;Kim, Hong-Jun;Ju, Young-Sung
    • Korean Journal of Oriental Medicine
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    • v.12 no.1
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    • pp.23-38
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    • 2006
  • The taxonomic list of specific features in external and internal shape and the pattern analysis of Aconitum carmichalei $D_{EBX}$ as the original plant of Aconiti Lateralis Radix Preparata and Aconitum cliiare Dc as the original plant of Aconiti Ciliare Tuber are as follows. 1. Aconitum carmichalei $D_{EBX}$ has tri-palmately parted leaves, petiole in lower leaves, and its ovary has short hair. Whereas Aconitum cliare Dc has $3{\sim}4$ parted leaves, long petiole, and its ovary has not hair. 2. Aconitum carmichalei $D_{EBX}$ has cylinder shape is relatively small in length and diameter, is greyish brown blacky brown in outer surface, greyish $white{\sim}dark$ gray in section. 3. According to the collection place, there is a remarkable difference in the physical shape of herbal states. Aconiti Lateralis Radix Preparate(medicated in Korea) is more transparent blacky brown color than Aconiti Lateralis Fadix Preparata(medicated in Chian). Also Black Aconi Radix(墨附片) has exodermis and White Aconi Radix(白附片) has not. 4. The internal characteristics entirely correspond to in internal shape described in the literatures, Only it is possible to discriminate between black Aconi Radix(墨附片) and White Aconi Radix(白附片) by the existence of cork layer. The classification between Aconiti Lateralis Radix Preparata and Aconiti Ciliare Tuber makes entirely Tuber makes entirely remarkable difference in the physical shape of cambium layer Namely, in shape of cambium layer the kinds of Aconiti lateralis Radix Prepala has horn-like shape and the kinds of Aconiti Ciliare Tuber has circle-like shape. 5. In the peak of examination substance in comparison to Rt of the index material diterpene alkaloid mesaconitine, aconitine, hypaconitine chromatogram Aconiti Ciliare Tuber is higher than in Aconiti Lateralis Radix Preparata This explain that the component changes after the process of medicine. 6. In the Content of mesaconitine, aconitine and hypaconitime Aconiti Ciliare Tuber is higher than Aconiti Lateralis Radix Preparata. 7. In Aconiti Lateralis Radix Preparata, aconitine, hypaconitine and mesaconitine each appears in Rf 0.46, 0.54, 0.32. But except Aconiti Ciliare Tuber the band does not appear. For the future, such results will be used as the basic source of additional research, and a far-reaching comparative study is needed to distinguish between many kinds of same genus-degree of relatedness.

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Intraoperative Radiotherapy (IORT) for Locally Advanced Colorectal Cancer (대장-직장암의 수술중 방사선 치료)

  • Kim, Myung-Se;Kim, Sung-Kyu;Kim, Jae-Hwang;Kwan, Koing-Bo;Kim, Heung-Dae
    • Radiation Oncology Journal
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    • v.9 no.2
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    • pp.265-270
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    • 1991
  • Colorectal cancer is the second most frequent malignant tumor in the United States and fourth most frequent tumor in Korea. Surgery has been used as a primary treatment modality but reported overall survivals after curative resection were from $20\%\;to\;50\%$. Local recurrence is the most common failure in the treatment of locally advanced colorectal cancer. Once recurrence has developed, surgery has rarely the role and the five year survival of locally advanced rectal cancer is less than $5\%$, in spite of massive combination therapy. Intraoperative radiotherapy (IORT) with or without external beam irradiation has been advocated for reducing local recurrence and improving survival. The recent report of local failure by this modality was only $5\%$, this indicated that significant improvement of local control could be achieved. We performed 6 cases of IORT for locally advanced colorectal cancer which is the first experience in Korea. Patient's eligibility, treatment applicator, electron energy, dose distribution on the surface and depth within the treatment field and detailed skills are discussed. We hope that our IORT protocol can reduce local failure and increase the long term survival significantly.

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A study on the Red Painting of stone monuments (비석(碑石)에 칠해진 주사(朱砂)안료에 관한 연구)

  • Shin, Eun-Jung;Han, Min-Su;Kang, Dai-Il
    • Korean Journal of Heritage: History & Science
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    • v.38
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    • pp.359-385
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    • 2005
  • Red ocher, red lead or cinnabar has been as red colorant for ages. Cinnabar of the red pigments has been highly regarded as a valuable ingredient because it represent a symbol of exorcising and a haute image. It was used as a pigment of painting and mural painting, bowl, clothes, rock writing, gravestone, etc. It is powder which dissolves in perilla oil or glue before using. Because it is high-priced, the use of cinnabar may be limited to the privileged class. Therefore, red ocher or red lead was used instead of cinnabar. "Gongsagyunmunrok" demonstrated that government official's gravestonea has been painted red by two colorants in the period of the Goryeo dynasty. However, cinnabar may be used to paint gravestones for the first time in the period of the Three States because it has been transmitted since the times. This study discuss the results obtained from an analysis of the pigments used on the red pigments of the Stone Monuments. The results can be briefly summarized as below; First, the microcrystalline structures seen on the surface section of analyzed pigments, samples of which were taken from various parts of red pigments show that different sizes and shapes of pigment particle. Second, a result of the analysis on the composition and structure of the pigments shows that the main components in their composition are : Red pigments - Red lead($Pb_3O_4$), Cinnabar(HgS) and Hematite($Fe_2O_3$) White pigments - Calcite($CaCO_3$) Especially, we knew that red Stone Monuments were found to be natural mineral pigments, which were used as a singular or a mixture.

Interpretation of 'Hakyibulsajang (學而不思章)' on Analects of Confucius (『논어』 '학이불사장(學而不思章)' 고석(考釋) - 특히 수양방법을 중심으로 -)

  • Kim, Young-Ho
    • The Journal of Korean Philosophical History
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    • no.58
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    • pp.279-305
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    • 2018
  • Confucius stressed both 'study (學)' and 'thinking (思)' but the two notions are complementary. To precisely measure the importance of the two, however, 'study' outweighs 'thinking.' Yet Confucius primarily states three steps on Analects of Confucius. In other words, Confucius mentioned two steps on 'Haksajang (學思章)' on the surface but it is actually composed of three steps. Then what is the step three? It is a critical issue to grasp the core of Confucius' idea. The ultimate goal of Confucius' idea is, as stressed by Cheng Yi (程伊川), to 'reach the realm of saint by learning,' which refers to a saint as an ideal human character. This paper is to examine three steps of 'oneness of study and thinking (學思合一)' as a way of Confucius' academic methodology to be the saint along with its structure. Saint, in a word, is characterized as 'communication (通).' It means communication through learning and thinking, which are the three steps of study(學)-thinking (思)-communication(通). Confucius emphasizes that this step also is a process itself (知) but it can be truly completed (dual structure) only by practice (行). Eventually, Confucius' academic methodology is of learning scriptures (學), thinking based on this learning (思) and practicing (行) based on this entire procedure (通). In other words, it is of a dual structure with three steps of 知 (study(學)-thinking(思)-communication(通))-practice(行).

Expanded Workflow Development for OSINT(Open Source Intelligence)-based Profiling with Timeline (공개정보 기반 타임라인 프로파일링을 위한 확장된 워크플로우 개발)

  • Kwon, Heewon;Jin, Seoyoung;Sim, Minsun;Kwon, Hyemin;Lee, Insoo;Lee, Seunghoon;Kim, Myuhngjoo
    • Journal of Digital Convergence
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    • v.19 no.3
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    • pp.187-194
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    • 2021
  • OSINT(Open Source Intelligence), rapidly increasing on the surface web in various forms, can also be used for criminal investigations by using profiling. This technique has become quite common in foreign investigative agencies such as the United States. On the other hand, in Korea, it is not used a lot, and there is a large deviation in the quantity and quality of information acquired according to the experience and knowledge level of investigator. Unlike Bazzell's most well-known model, we designed a Korean-style OSINT-based profiling technique that considers the Korean web environment and provides timeline information, focusing on the improved workflow. The database schema to improve the efficiency of profiling is also presented. Using this, we can obtain search results that guarantee a certain level of quantity and quality. And it can also be used as a standard training course. To increase the effectiveness and efficiency of criminal investigations using this technique, it is necessary to strengthen the legal basis and to introduce automation technologies.