국소 Compact Hⓒ-groups와 Han-group에 대하여

한정순,임종록 한양대학교 이학기술연구소 2000 이학기술연구지 Vol.2 No.

이 논문에서 우리는 Han-groups 의 몇 가지 흥미 있는 특성을 가지고 있는 groups의 더 일반적인 class에 관심을 가지고 있다. 우리는 몇몇의 이러한 특성을 얻고 더 일반적인 class의 특성이 Han-groups 임을 결정하고자 시도한다. 그리고 우리는 a compactly generated H-group은 Han-group임을 증명한다. 이 결과는 다음 (a locally compact H-group은 unimodular)을 포함하여 몇 가지 응용을 가진다. In this paper, we are interested in a more general class of groups which share some of the interesting properties of Han-groups. We obtain some of properties and attempt to determine which of the more general class are Han-groups. We prove that a compactly generated H-group is a Han-group. This result has applications, including the following ; A locally compact H-group is unimodular.

동진강 수계 농업용수 수질평가

한수곤,최정식,문영훈,엄미정,김갑철 한국환경농학회 2000 한국환경농학회지 Vol.19 No.2

동진강 수계의 수질현황을 파악하기 1994∼1998년 까지 4∼9월에 월 1회에 걸쳐 5개년간 조사한 결과를 요약하면 다음과 같다. 월별로는 빗물에 의한 희석효과로 7, 8월에 수질이 가장 양호하였으며, 4월이 다소 불량하였으나 수도생육 피해 한계농도에는 미치지 못하는 수준이었다. 지점별 수질현황은 생활하수 유입지인 정읍천과 지천의 폭이 좁은 원평천의 무기성분 함량이 높았으며 동진천 상류지역에서 가장 양호하였다. 연도별 현황은 '94년 이후 '95년까지는 수질이 악화되는 경향을 보였으나 '95년 이후로는 각 성분 함량이 낮았지는 등 점점 양호해지고 있으며 COD함량으로 볼 때 특히, 정읍천의 수질이 개선되고 있음을 알 수 있었다. 양이온과 음이온의 총당량온 4월에 가장 높았고 7, 8월에 가장 낮았으며 양이온/음이온의 당량비는 5월에 높았고 7월이 가장 낮았으며 지점에 따라서는 총당량은 정읍천, 원평천, 동진천 하류, 중류, 상류의 순위였으며 양이온/음이온 총당량 비율은 원평천이 상대적으로 작은 수치를 보였지만 지역간 큰 차이는 보이지 않았다. 수질 중 각 성분 상호간의 상관관계를 보면, 대개의 성분 상호간에 유의성이 높게 나타났으나, NO₄^--N는 대개의 성분과 유의성이 없었고, PO₄^(3-)-P도 COD, NH₄^+-N, NO₃^--N, SO₄^(2-)과는 유의성을 보이지 않았다. This study was conducted to monitor the irrigation water qualities along Dong-Jin river watershed. The water quality was surveyed at 6 sites from April to september during 1994∼1998. And the results were as follows : In July and August, water quality was better than that of any other months due to dilution with rainwater. Whereas, it became worse in April but it involved lower contents than limitted contents affected to the crop damage. Content of inorganic components was higher at Jeong-up and Won-pyeong stream. The reason for it that Jeong-up stream was deteriorated with sewage water from Jeong-up city, and Won-pyeong stream has narrow width. Water quality in upstream of Dong-Jin river, was evaluated best conditions in all sampling sites. For investigated period, water quality got worse from 1994 to 1995 but it was getting better to 1998 after 1995, especially at Jeong-up stream. The total equivalent of cation and anion was the highest at April through all months and at Jeong-up stream in sampling sites. Equivalent ratio of cation to anions(∑C/∑A) was higher at May than any other months and lower at Won-pyeong streams than any other sites. The value of most inorganic components was highly correlated with those of other components. But the value of NO₃^--N was not correlated with that of most components, and PO₄^(3-)-P was not correlated with COD, NH₄^+-N, NO₃^--N, SO₄^(2-_.

Effect of Mechanical Alloying on the Microstructural Evolution of Al60Cr30Si10 Alloys Processed by Spark Plasma Sintering

Jeong‑Han Lee,Ik‑Hyun Oh,Jun‑Ho Jang,Ju‑Hun Kim,Sung‑Kil Hong,Hyun‑Kuk Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

In this study, Al, Cr and Si fine powders were alloyed by planetary ball milling to investigate their microstructural evolution,following their mechanical alloying behavior. The formation of Al(Cr) supersaturated solid solution by the Cr grainsembedded in Al-matrix, which contributed substitutional structure is discussed in relation to their structural evolution inaccordance with the distortion of a crystal lattice. The compacts of Al–Cr–Si alloys were prepared by rapid sintering withina short time by dense consolidation above the density of 99.9% as the formation of intermetallics, except in the case of thedistribution of single-phases induced by the Al-melting. The formation behavior of intermetallics was dominated by dependenceon the structures of the milled-powder and subsequent sintering temperature. To estimate the consolidated behaviorsof compacts, various approaches derived from TEM and XRD analysis were taken to obtain microstructural evidences ofthe inter-diffusion, following the presence of thermally stable intermetallics.

Allophony and Contrast in Speech Perception

Han,Jeong-Im 한국언어학회 2009 언어 Vol.34 No.1

The present study examines the perceptual status of allophones to examine the interaction of the phonological knowledge and speech perception. With the use of Korean bilabial stops, phonemic, allophonic and two types of low-level phonetic pairs were generated, and their perception by Korean listeners was examined. Through a categorial AXB discrimination and similarity rating tasks, it was shown that phonemes are fully discriminated, while other categories are less. However, there were significant differences in similarity ratings between the tokens for an allophone pair and two identical tokens, suggesting that allophones are also discriminated by natives. Furthermore, perceptual discrimination of phonological and phonetic categories was shown to be influenced by lexicality and partly by episodic information such as token frequency. The relevance of the results to exemplar models is discussed.

오리부산물과 한약재를 이용한 추출액의 영양성분 및 중금속 노출에 대한 피해 완화 효과 : (Ⅱ) 중금속 노출에 대한 오리추출액의 피해 완화 효과 (Ⅱ) Damage Mitigation Effects on Heavy-metals Exposure of Peking-Duck By-Product Extracts

한종현,이우진,조성균,이미정,정미란,전정우,김운영,박성혜 동아시아식생활학회 2003 동아시아식생활학회지 Vol.13 No.4

This study was performed to investigate the effects of peking-duck extracts added with medicinal herbs(DJ) on the intoxication of heavy metals (Hg, Pb, Cd, As) in rats. Sprague-Dawley rats weighing 150±15g, were randomly assigned to 5 groups: basal diet only in normal control group(NCG); basal diet and heavy metals without DJ injection in heavy metal control group(HMC); basal diet, heavy metals and DJ(3㎎/㎖) injection in heavy metal low duck juice group(HMLD), basal diet, heavy metals and DJ(30㎎/㎖) injection in heavy metal middle duck juice group(HMMlD); basal diet, heavy metal and DJ(300㎎/㎖) injection in heavy metal high duck juice group(HMHD). Hg and As was injected by 50ppm and Cd and Pb by 25ppm for 17days. Also DJ oral feeding was conducted for 28days. The result of this study were as follows: Food intake and body weight gain in heavy metal administered groups were lower than those of NCG. Liver, kidney and testis weights were not significantly different among 5 groups. GOT, GPT and BUN activities were significantly reduced in DJ treated groups as compared to HMC. DJ showed the suppressing effect on the accumulation of Hg, Pb and Cd in serum, liver and kidney. Fecal Hg and Cd excretions increased with DJ feeding. The results suggested that DJ may have some protective effects on Hg, Cd and Pb intoxication by reducing the accumulation m tissues and increasing excretion. This study also showed the effective way of using duck-extract and its application to the oriental medicine.

Characterization and Property Evaluation of Ti‑Based Target Materials and Their Nitride Nano‑composites Coating Layers

Jeong‑Han Lee,Hyun‑Kuk Park,장준호,Ik‑Hyun Oh 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.1

This study formed a hard TiAlSiWN coating layer using Ti, Al, Si and W raw powders that were mechanically alloyed andrefined. The TiAlSi and TiAlSiW coating targets were fabricated using a pulse current activated sintering process in a shorttime with the optimal sintering conditions. The optimized sintering condition was obtained by controlling process parameterssuch as temperature, pressure, heating rate and pulse ratio (on/off). The coating targets were successfully deposited onthe WC substrate to form the TiAlSiN and TiAlSiWN nitride nano-composite structures by an arc ion plating process andalso, their coating layers were compared according to the addition of W element. The microstructures of the nitride nanocompositecoating layer were analyzed, focusing on the distribution of the crystalline phases, amorphous phases (Si3N4),and growth orientation of the columnar crystal depending on the addition of W element. The mechanical properties of thecoating layers were exhibited a hardness of approximately 3000 kg/mm2 and adhesion of about 117.77 N in the TiAlSiN. Inparticular, the TiAlSiWN showed excellent properties with a hardness of more than 4300 kg/mm2 and an adhesion of about181.47 N, respectively.

Rapid Consolidation of WC‑ZrSiO4 Hard Materials by Spark Plasma Sintering: Microstructure, Densification, and Mechanical Properties

Jeong‑Han Lee,Ik‑Hyun Oh,Ju‑Hun Kim,Sung‑Kil Hong,Hyun‑Kuk Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.9

Densely consolidated WC-based hard materials with 5–20 vol% ZrSiO4was fabricated by spark plasma sintering at 1400 ℃ ata constant heating rate of 70 ℃/min−1. To achieve mechanical alloying of WC-ZrSiO4, planetary ball milling was carried outfor 12 h, during which the brittle-brittle components (WC-ZrSiO4) became fragmented and their particles became refined. Itwas observed that certain, specific, non-isothermal sintering kinetics, such as apparent activation energy, sintering exponents,and densification strain, affected the densification behavior. The evolution of phase structure from powder to compact wasfound to be related the lattice distortion and micro-strain in the basal planes of WC. By examining the mechanical propertiesof the samples, it was that the added zircon content leads to enhanced fracture toughness (12.9 MPa m1/2) owing to thepresence of WC-ZrSiO4 in the cemented carbide. In fact, the microcrack propagation of the fracture passed through zirconfrom a transgranular to a ductile component (fcc) where the crack tips could be absorbed.

Influence of Phase Composition in TiAlSiN Hard Coatings on the Evolution of Structure and Mechanical Properties

Jeong‑Han Lee,Ik‑Hyun Oh,Jun‑Ho Jang,Ju‑Hun Kim,Sung‑Kil Hong,Hyun‑Kuk Park 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.3

The aim of this study is to investigate the structural evolution and mechanical properties of TiAlSiN coatings when processedby the arc ion plating method. To form a hard coating, Ti, Al, and Si powders were mechanically alloyed by planetary ballmilling; the powders were then densely compacted during a rapid sintering process into a ternary system coating, i.e. TiAlSi. The evolution of the structural phase from a powder to a compact material is dominated considerably by phase states suchas a supersaturated solid solution or intermetallic compounds. In the case of coating layers, the factors that determine thestructural evolution are associated with the phase stability of the nano-crystalline structure that in turn is associated withthe Ti/Al composition ratio. Motivated by this, we performed experiments to investigate the distribution of microstructures;the material’s binding energy, quantitative properties, transformation of crystal structure, and distribution of amorphous/crystalline were all recorded. In particular, the relationship between the physical and chemical properties during the coatingprocess is considered to be the dominant factor controlling the orientation and morphology of that zone (1, T, and 2). TheTiAlSiN coating layer was found to have hardness above 45 GPa and an adhesion above 100 N. In other words, understandingthe evolution and structure of TiAlSin helped us to produce a material with excellent properties that can be used as a hardcoating. Specifically, these properties were induced by a grain refinement of the nano-crystalline structure that correspondsto an increase in the silicon nitride contents.

보리를 이용한 가공식품 제조와 그 특성

고정은,양영택,송살철,김정숙,한동휴,고정삼 濟州大學校亞熱帶農業硏究所 1996 亞熱帶農業硏究 Vol.13 No.-

요약 제주산 보리차 및 보리음료 제조를 위한 원료의 일반성분과 무기물을 분석하였으며, 상품화 가능성을 관능검사를 통하여 평가하였다. 일반성분 및 무기물의 분석결과, 원료의 종류에 따라 다소의 차이는 있었으나 대체적으로 표준분석값과 유사하였다. 보리차의 경우 시판하고 있는 회사제품과의 차별화를 위하여 볶음결명자, 볶음옥수수, 살구씨 등을 혼합한 형태의 보리차 기호성을 검토하였다. 볶음보리만을 이용한 보리차보다는 볶음보리에 볶음결명자, 볶음옥수수, 살구씨를 16 : 1.5 : 2 : 0.5의 비율로 각각 첨가한 보리차를 가장 선호하였다. 그리고 볶음 정도에 따라 추출한 보리차의 색깔이 차이를 나타내었으며, 시판하는 보리차의 흡광도가 420nm에서 0.369인데 비하여 볶음정도가 낮은 시제품의 흡광도는 0.182로서 약간 연한 색깔을 선호하였다. 보리음료의 경우, 미숫가루만을 사용할 때는 볶음보리가루 : 물을 1 : 9로 하고 여기에 첨가하는 설탕농도를 9%로 하는 것에 가장 좋은 선호도를 나타내었다. 그러나 볶음보리가루만을 사용한 경우는 향미가 약하여 기호성가 떨어진 반면 미숫가루 : 볶음찹쌀가루 : 볶음콩가루 : 볶음참깨가루를 9 : 0.5 : 0.3 : 0.2의 비율로 혼합한 혼합가루 10g에 설탕 6g의 비율로 사용하는 경우 기호성이 가장 좋았다. 또한, 대용식인 조식시리얼로 미숫가루를 사용하는 경우 미숫가루 : 물을 10 : 4의 혼합비율로 하며, 미숫가루 : 볶음찹쌀가루 : 볶음콩가루 : 볶음참깨가루를 8 : 0.5 : 1.0 : 0.5의 비율로 혼합한 경우 기호성이 가장 좋았다. 미숫가루의 상품화를 위해서는 기호성의 향상을 위한 음용형태에 따른 배합비율의 최적화, 포장디자인 및 포장방법의 개선, 차별화를 위한 홍보 등이 필요할 것으로 판단된다. Summary Chemical analysis of barley and other cereals related to tea and beverage products, and sensory evaluation were investigated. Proximate compositions and inorganic elements contents of raw materials produced in Cheju were similiar to standard values. Blending at the ratio of 16 roasted barley, 1.5 roasted Cassia tora seed, 2 roasted corm, and 0.5 apricot seed was the better, compared to roasted barley only, for barley tea on sensory evaluation. According to the degree of roasting, the color of extracts with boiled water was different. Absorbance at 420nm of commercial barley extracts was 0.369, compared to the value of 0.182 on sample in this experiments. For barley beverage, 10% of roasted barley powder added 9% of sugar was the vest on sensory evaluations However, blending at the ratio of 9 roasted barley powder, 0.5 roasted glutinous rice powder, 0.3 roasted soybean powder, and 0.2 roasted sesame powder, added 6% of sugar, was the best, compared to roasted barley powder only, for barley beverage on sensory evaluations. On 40% of roasted barley powder only, for morning cereals, blending at the ratio of 8 roasted barley powder, 0.5 roasted glutinous rice powder, 1.0 roasted soybean powder, and 0.5 roasted sesame powder was the best on sensory evaluations, compared to roasted barley powder only.

보존적 치료로 회복된 망경색에 의한 급성복증 1예

김정념,이숭환,김정식,김진호,배윤오,박성규,윤상정,한현영,이헌영 충남대학교 의과대학 의학연구소 2003 충남의대잡지 Vol.30 No.1

Omental infarction, the end result of impaired perfusion to the greater omentum, is a rare benign self-limiting clinical entity. The main clinical symptom is non-specific localized abdominal pain with a moderately raised white blood cell and erythrocyte sedimentation rate. These findings often mimic an abdominal surgical emergency. This condition is often misdiagnosed as acute appendicitis or cholecystitis. The characteristic feature of CT scan and ultrasonography provide non-invasive diagnosis in most patients with omental infarction. We report a case of patient whose CT scan showed the characteristic finding of omental infarction. The patient was improved spontaneously only with conservative care.