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Integral Domains Whose ω-Integral Closures Are Krull Domains

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Algebra Colloquium 2020年第2期27卷 287-298页

Let D be an integral domain with quotient field K,D be the integral closure of D in K,and D^[w] be the ω-integral closure of D in K;so D ■ D^[w],and equality holds when D is Noetherian or dim(D)=*** Mori-Nagata theorem states that if D is Noetherian,then D is a Krull domain;it has also been investigated when D is a Dedekind *** study integral domains D such that D^[w] is a Krull *** also provide an example of an integral domain D such that D ■ D ■ D^[w],t-dim(D)=1,D is a Priifer multiplication domain with v-dim(D)=2,and D^[w] is a UFD.

关键词： Krull domain ω-integral closure PvMD t-Nagata ring weakly Dedekind domain

ψValuation ideals and primary w-ideals

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Frontiers of Mathematics in China 2016年第4期11卷 829-844页

作者： gyu whan chang Hwaukoo KIM Department of Mathematics Education Incheon National University Incheon 406-772 Republic of Korea Department of Information Security Hoseo University Asan 336-795 Republic of Korea

Let D be an integral domain, ψ（D）（resp., t-ψ（D）） be the set of all valuation （resp., t-valuation） ideals of D, and w-P（D） be the set of primary w-ideals of D. Let D[X] be the polynomial ring over 19, c（f） be the ideal of D generated by the coefficients of f ∈ D[X], and Nv = {f∈ D[X] ｜ c（f）v = D}. In this paper, we study integral domains D in which w-P（D） t-ψ（D）, t-ψ（D） w-P（D）, or t-ψ（D） = w-P（D）. We also study the relationship between t-ψ（D） and ψ（D[X]Nv）, and characterize when t-ψ（A ＋ XB[X]） w-P（A ＋ XB[X]） holds for a proper extension A c B of integral domains.

关键词： t-Valuation ideal primary w-ideal PvMD UMT-domain D[X]Nv

Integral domains with finitely many spectral semistar operations

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Frontiers of Mathematics in China 2017年第1期12卷 35-49页

作者： gyu whan chang Dong Yeol OH Department of Mathematics Education Incheon National University Incheon 22012 Republic of Korea Department of Mathematics Education Chosun University Gwangju 61452Republic of Korea

Let D be a finite-dimensional integral domain, Spec（D） be the set of prime ideals of D, and SpSS（D） be the set of spectral semistar operations on D. Mimouni gave a complete description for the prime ideal structure of D with ｜SpSS（D）｜ = n ＋ dim（D） for 1 ≤ n ≤5 except for the quasi-local cases of n = 4, 5. In this paper, we show that there is an integral domain D such that ｜SpSS（D）｜ = n＋dim（D） for all positive integers n with n ≠ 2. As corollaries, we completely characterize the quasi-local domains D with ｜SpSS（D）｜= n＋dim（D） for n = 4, 5. Furthermore, we also present the lower and upper bounds of ISpSS（D）I when Spee（D） is a finite tree.

关键词： (Spectral) semistar operation prime spectrum (Krull) dimension

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星算子和强有限型理想(英文)

吉林师范大学学报（自然科学版） 2009年第3期30卷 19-22页

作者：张圭焕仁川大学校数学科

设R是具有单位元的可交换环,*是R上的一个有限型星算子.我们证得如果R上的一个星-理想I的每个极小素理想是星-强有限型理想,则I也是一个星-强有限型理想.作为推论,我们给出R上的每个星-理想是星-强有限型理想当且仅当R的每个根星-理想是... 详细信息

设R是具有单位元的可交换环,*是R上的一个有限型星算子.我们证得如果R上的一个星-理想I的每个极小素理想是星-强有限型理想,则I也是一个星-强有限型理想.作为推论,我们给出R上的每个星-理想是星-强有限型理想当且仅当R的每个根星-理想是星-强有限型理想,当且仅当R的每个素星-理想是星-强有限型理想.设I是一个Prufer星乘域R上的一个非零理想.我们证得I是R的一个星-强有限型理想当且仅当I[X]N是R[X]N的一个星-强有限型理想.

关键词：有限型星算子星-强有限型理想 Prufer星乘域

Common bile duct stones on multidetector computed tomography:Attenuation patterns and detectability

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World Journal of Gastroenterology 2013年第11期19卷 1788-1796页

作者： chang whan Kim Jae Hyuck chang Yeon Soo Lim Tae Ho Kim In Seok Lee Sok Won Han Department of Internal Medicine College of MedicineThe Catholic University of Korea505 BanpoDongSeocho-GuSeoul 137-701South Korea Department of Radiology College of MedicineThe Catholic University of Korea505 Banpo-DongSeocho-GuSeoul 137-701South Korea

AIM:To investigate the attenuation patterns and detectability of common bile duct(CBD) stones by multidetector computed tomography(MDCT).METHODS:Between March 2010 and February 2012,191 patients with suspicion of CBD stones undergoing both MDCT and endoscopic retrograde cholangiopancreatography(ERCP) were enrolled and reviewed *** attenuation patterns of CBD stones on MDCT were classified as heavily calcified,radiopaque,less radiopaque,or *** association between the attenuation patterns of CBD stones on MDCT and stone type consisting of pure cholesterol,mixed cholesterol,brown pigment,and black pigment and the factors related to the detectability of CBD stones by MDCT were ***:MDCT showed CBD stones in 111 of 130 patients in whom the CBD stones were demonstrated by ERCP with 85.4% *** attenuation patterns of CBD stones on MDCT were heavily calcified 34(26%),radiopaque 31(24%),less radiopaque 46(35%),and undetectable 19(15%).The radiopacity of CBD stones differed significantly according to stone type(P < 0.001).From the receiver operating characteristic curve,stone size was useful for the determination of CBD stone by MDCT(area under curve 0.779,P < 0.001) and appropriate cut-off stone size on MDCT was 5 *** factors related to detectability of CBD stones on MDCT were age,stone type,and stone size on multivariate analysis(P < 0.05).CONCLUSION:The radiopacity of CBD stones on MDCT differed according to stone *** type and stone size were related to the detectability by MDCT,and appropriate cut-off stone size was 5 mm.

关键词： Common bile duct gallstones Gallstones Multidetector computed tomography Endoscopic retrograde cholangiography

Proportion and clinical features of never-smokers with non-small cell lung cancer

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Chinese Journal of Cancer 2017年第2期36卷 81-87页

作者： Jaeyoung Cho Sun Mi Choi Jinwoo Lee chang-Hoon Lee Sang-Min Lee Dong-Wan Kim Jae-Joon Yim Young Tae Kim Chul-gyu Yoo Young whan Kim Sung Koo Han Young Sik Park Department of Internal Medicine Seoul National University HospitalSeoul 110-744Republic of Korea Department of Thoracic and Cardiovascular Surgery Seoul National University HospitalSeoul 110-744Republic of Korea

Background: The proportion of never?smokers with non?small cell lung cancer(NSCLC) is increasing, but that in Korea has not been well addressed in a large population. We aimed to evaluate the proportion and clinical features of never?smokers with NSCLC in a large single ***: We analyzed clinical data of 1860 consecutive patients who were newly diagnosed with NSCLC between June 2011 and December ***: Of the 1860 NSCLC patients, 707(38.0%) were never?smokers. The proportions of women(83.7% vs. 5.6%) and adenocarcinoma(89.8% vs. 44.9%) were higher among never?smokers than among ever?smokers. Significantly more never?smokers were diagnosed at a younger median age(65 vs. 68 years, P < 0.001) and earlier stage(stage I–II, 44.5% vs. 38.9%, P < 0.001) a= 0.015) compared with ever?smokers. Epidermal growth factor receptor mutations(57.8% vs. 24.4%, Pnd anaplastic lymphoma kinase rearrangements(7.8% vs. 2.8%, P < 0.001) were more common in never?smokers, whereas Kirsten rat sarcoma viral oncogene homolog mutations(5.8% vs. 9.6%, P ntly encountered in never?smokers than in ever?smokers. Never?smokers showed longer su= 0.021) were less frequervival after adjust?ing for the favorable effects of younger age, female sex, adenocarcinoma histology, better performance status, early stage disease, being asymptomatic at diagnosis, received antitumor treatment, and the presence of driver mutations(hazard ratio, 0.624; 95% confidence interval, 0.460–0.848; P = 0.003).Conclusions: More than one?third of the Korean patients with NSCLC were never?smokers. NSCLC in never?smokers had different clinical characteristics and major driver mutations and resulted in longer overall survival compared with NSCLC in ever?smokers.

关键词： Non-small cell lung carcinoma Never-smoker Epidermal growth factor receptor KRAS Prognosis

Middle Paleozoic metamorphic and sedimentary events in the central Korean Peninsula and their geological implications

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Geoscience Frontiers 2024年第5期15卷 136-161页

作者： Byung Choon Lee Sung Won Kim Bo Young Lee chang whan Oh Deung-Lyong Cho Weon-Seo Kee Department of Earth and Environmental Sciences Chonnam National University77Yongbong-roBuk-guGwangju 61186Republic of Korea Geology and Space Division Korea Institute of Geoscience and Mineral ResourcesDaejeon 34132Republic of Korea Department of Earth and Environmental Sciences Jeonbuk National UniversityJeonju 561-756Republic of Korea

The Middle Paleozoic tectonic evolution of the central Korean Peninsula(Gyeonggi Massif,Hongseong-Imjingang,and Okcheon zone of Okcheon Belts)remains ***,the occurrence of high-grade metamorphism and sedimentation need further *** this study,we conducted zircon U-Pb-rare earth element analyses from in the ultramafic-mafic complex in the central Korean Peninsula(Cheonan and Gapyeong areas)and the Paleozoic metasedimentary rocks in the Okcheon Zone of the Okcheon Belt to constrain the timing of maximum depositional and metamorphic *** also examined the metamorphic P-T-t path from garnet-bearing amphibolite in the central Korean Peninsula by pseudosection modeling and *** results show that(i)some of the ultramafic-mafic complex and metasedimentary rocks in the central Korean Peninsula formed during the Middle Paleozoic(ca.450–374 Ma);(ii)garnet-bearing amphibolite underwent successive metamorphism from amphibolite facies condition(7.5–8.0 kbar and 540–630℃)at pre-peak stage to granulite facies condition(10.9–11.8 kbar and 740–820℃)at peak stage,and then retrograded into amphibolite facies condition(5.7–7.7 kbar and 530–670℃)along the clockwise P–T path during ca.403–362 *** and previous studies suggest that the central Korean Peninsula underwent subduction-related orogenic events during the Middle Paleozoic era,and it is well correlated to those of the orogenic events in the North Qinling belt.

关键词： Central Korean Peninsula Middle Paleozoic Orogenic event Pressure-temperature estimation Zircon U-Pb-REE analysis

Undiagnosed Borrmann type Ⅱ gastric cancer due to necrosis and regenerative epithelium

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World Journal of Gastroenterology 2014年第28期20卷 9621-9625页

作者： Joon Hur Jae Hyuck chang Byung Kee Kim Hoon Young Ko Jong Hwan Lee Soo Jeong Kim Mi Ae Song Tae Ho Kim chang whan Kim Sok Won Han Division of Gastroenterology Department of Internal MedicineBucheon St.Mary’s HospitalThe Catholic University of KoreaCollege of Medicine Department of Clinical Pathology Bucheon St.Mary’s HospitalThe Catholic University of KoreaCollege of Medicine

Endoscopic biopsy is essential to the proper diagnosis and treatment of gastric ***,the results of endoscopic biopsy are not always the same as what is expected based on gross endoscopic *** results of endoscopic biopsy can be negative for malignancy in Borrmann typeⅣadvanced gastric cancer(AGCa)or gastric ***,in the case of typeⅡAGCa,repeated biopsies negative for malignancy have not been reported.A 49-year-old male patient underwent esophagogastroduodenoscopy three times due to large gastric ulcer suspected to be Borrmann typeⅡ***,three repeat endoscopic biopsies with multiple specimens showed necrosis and superficial regenerative epithelium without malignant *** patient underwent laparoscopic distal gastrectomy with D2 lymph node *** surgical specimen revealed that the mucosal layer was completely replaced with regenerative epithelium without cancer cells.

关键词： Endoscopy Biopsy Stomach neoplasm Stomach ulcer Regeneration

Fabrication of GaAs/Si Heterostructures and Their Photoelectric Properties

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Semiconductor Photonics and Technology 2007年第2期13卷 146-149,163页

作者： LIU Xiang WU chang-shu ZHANG Peng-xiang LIU Li-lai Kim Tae-whan Institute of Advanced Materials for Photo-electronics Kunming University of Science and Technology Kunming 650051 CHN Department of Electronics and Computer Engineering Hanyang University Seoul 133-791 Korea

Fabrication of GaAs/Si heterostructures and their photoelectric properties are investigated by Raman, photoluminescence and Hall-effect measurements. The crystallinity of GaAs epilayers grown on Si substrate is significantly affected by the substrate orientation and the growth method. The photoelectric properties of GaAs epilayers grown on Si (211) substrates deposited by using a two-step growth method are improved. These results indicate that GaAs epilayers grown on Si (100) and Si (211) substrates by using two-step growth method are promising for potential applications in high-speed and high-frequency photoelectric devices.

关键词： heterostructure two-step growth buffer layer