• Journal of applied mathematics & informatics
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• 제22권1_2호
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• pp.403-410
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• 2006

For a finite group G, #Cent(G) denotes the number of centralizers of its elements. A group G is called n-centralizer if #Cent(G) = n, and primitive n-centralizer if #Cent(G) = #Cent($\frac{G}{Z(G)}$) = n. The first author in [1], characterized the primitive 6-centralizer finite groups. In this paper we continue this problem and characterize the primitive 7-centralizer finite groups. We prove that a finite group G is primitive 7-centralizer if and only if $\frac{G}{Z(G)}{\simeq}D_{10}$ or R, where R is the semidirect product of a cyclic group of order 5 by a cyclic group of order 4 acting faithfully. Also, we compute #Cent(G) for some finite groups, using the structure of G modulu its center.

• Tuberculosis and Respiratory Diseases
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• 제43권2호
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• pp.190-200
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• 1996

연구배경 : 장기간 진행된 심한 만성 기도 폐쇄질환 환자에서 합병된 급성 호흡부전의 치료로 기관삽관과 기계호흡이 필요한 경우가 있다. 그러나 기계호흡을 거부하거나 기계호흡의 이탈이 불가능할 것으로 예측되는 환자에서 기관삽관과 기계호흡을 대신할 수 있는 환기법이 필요할 것으로 생각된다. 최근 수면 무호흡질환 환자의 치료로 개발되었던 지속적 기도 양압 치료가 급성 혹은 만성 호흡부전의 치료로 시도되고 있다. 본 연구에서는 급성 호흡부전이 합병된 만성 기도 폐쇄환자에서 비강 마스크를 통한 BiPAP 치료를 실시하여 그 효과를 평가하였다. 방법 : 영남대학교 의과대학 부속병원 내과에 내원한 만성 기도 폐쇄환자 22명을 대상으로 하여, BiPAP 치료군으로 10명의 만성 폐쇄성 폐질 환자와 1명의 기관지 천식환자에게는 대증적 치료 및 BiPAP 치료를 동시에 실시하였고, 대조군으로 11명의 만성 폐쇄성 폐질환자에게는 대증적 치료만 시행하였다. 대증적 치료는 산소 요법, 아미노필린, 부신피질 호르몬 흡입, 베타 agonist 등의 약물을 투여하였고 BiPAP 치료시 mode는 spontaneous timed, 호흡 빈도는 분당 12회에서 20회, IPAP는 $6cmH_2O$에서 $8cmH_2O$, EPAP는 $3cmH_2O$에서 $4cmH_2O$로 설정하였고 사용 기간은 3일간이었다. 치료 효과는 호흡 빈도, modified Borg scale 및 동맥혈 가스소견으로 비교하였다. 결과 : BiPAP 치료군과 대조군 사이에 나이, 치료 시작전 호흡 빈도 동맥혈 가스소견, modified Borg scale 그리고 안정 상태에서 시행한 환기 기능검사 소견은 양군 사이에 차이가 없었다. 호흡빈도와 modified Borg scale은 BiPAP 치료군과 대조군에서 시간의 경과에 따라 모두 유의하게 호전되었으나 두군간의 차이는 없었다. 동맥혈 산소 BiPAP 치료군과 대조군에서 다 같이 치료전에 비해 치료 1일 및 3일후에는 시간에 경과에 따라 호전되었으나 BiPAP 치료군에서는 치료 1일후와 치료 3일후의 소견에도 뚜렷한 호전이 있었던 반면에 대조군에서는 의미있는 차이가 없었다. BiPAP치료군에서는 동맥혈 이산화탄소분압은 치료전과 비교하여 치료 1일후 및 3일후에는 각각 유의하게 감소되었으나 대조군에서는 유의한 감소가 없었다. pH는 BiPAP 치료군에서 치료전과 비교하여 3일후에 의의있게 증가하였으나 대조군에서는 뚜렷한 차이가 없었다. 대조군과 BiPAP치료군의 치료 전후의 평균 동맥혈가스 차이로 두 군간의 비교에서도 동맥혈 산소분압은 치료 3일째, 동맥혈 이산화탄소 분압은 치료 1일째와 3일째, pH는 치료 3일째에 각각 의미있는 (p<0.05) 차이를 보였다. 결론 : 이상의 결과로 중증 만성 폐쇄성 폐질환 환자에서 급성 호흡부전이 발생시 BiPAP 치료는 호흡곤란과 동맥혈 호흡성 가스 소견을 향상시킬 수 있는 보조적인 환기법이 될 수 있겠으며 기관 삽관에 의한 인공호흡을 대신할 수도 있을 것으로 생각된다.

• 한국자기공명학회논문지
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• 제17권1호
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• pp.24-29
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• 2013

The structural characteristics of 4-coordinate $BO_4$ [B(1)] and 3-coordinate $BO_3$ [B(2)] groups in $BiB_3O_6$ were studied by $^{11}B$ magic angle spinning (MAS) and single-crystal nuclear magnetic resonance (NMR) spectroscopy. The spin-lattice relaxation time in the laboratory frame, $T_1$, for $^{11}B$ decreased slowly with increasing temperature, whereas the spin-lattice relaxation times in the rotating frame, $T_{1{\rho}}$, for B(1) and B(2), which differed from $T_1$, were nearly constant. Further, $T_{1{\rho}}$ for B(1) and B(2) showed very similar trends, although the $T_{1{\rho}}$ value of B(2) was shorter than that of B(1). The 3-coordinate $BO_3$ and 4-coordinate $BO_4$ were distinguished by $^{11}B$ MAS NMR spectrum and $T_{1{\rho}}$.

• 천문학회지
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• 제40권4호
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• pp.123-125
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• 2007

NGC 1333 is a nearby star forming region, and IRAS 4A and IRAS 4BI are low-mass Class 0 protostars. IRAS 4A is a protobinary system. The NGC 1333 IRAS 4 region was observed in the 22 GHz water maser with a high resolution (0.08") using the Very Large Array. Two groups of masers were detected: one near A2 and the other near BI. Most of the masers associated with A2 are located very close (< 100 AU) to the radio continuum source. They may be associated with the circumstellar disk. Since no maser was detected near AI, the A2 disk is relatively more active than the Al disk. Most of the masers in the BI region are distributed along a straight line, and they are probably related with the outflow. As in many other water maser sources, the IRAS 4 water masers seem to trace selectively either the disk or the outflow. Considering the outflow lifetimes, the disk-outflow dichotomy is probably unrelated with the evolutionary stage of protostars. A possible explanation may be that both the outflow-maser and the disk-maser are rare phenomena and that detecting both kinds of maser around a single protostar may be even rarer.

• Asian Journal for Public Opinion Research
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• 제7권3호
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• pp.143-168
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• 2019

With much attention being paid to the rapid growth of wrist-worn smart devices, this study aimed to examine the micro-processes that determine an individual's adoption of smart bands and smartwatches. Primarily relying on the theoretical background of the extended technology acceptance model (TAM II), this study explored relationships between three groups of predictors-social, personal, and device-oriented-and the three main components of the original TAM: perceived usefulness (PU), perceived ease of use (PEOU), and behavioral intention (BI). Results from the path analysis indicated multiple factors played significant roles in increasing the PU, PEOU, and BI of wristworn smart devices: subjective norms, social image, self-efficacy, perceived service diversity, and perceived reasonable cost. The main findings from this research contribute to significantly improving the understanding of the main factors leading people to adopt wrist-worn smart devices.

• 대한수학회보
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• 제60권6호
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• pp.1607-1620
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• 2023

In this paper, we mainly study the problem of the existence of homogeneous geodesics in sub-Finsler manifolds. Firstly, we obtain a characterization of a homogeneous curve to be a geodesic. Then we show that every compact connected homogeneous sub-Finsler manifold and Carnot group admits at least one homogeneous geodesic through each point. Finally, we study a special class of ℓ^p-type bi-invariant metrics on compact semi-simple Lie groups. We show that every homogeneous curve in such a metric space is a geodesic. Moreover, we prove that the Alexandrov curvature of the metric space is neither non-positive nor non-negative.

• Asian Pacific Journal of Cancer Prevention
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• 제15권7호
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• pp.3179-3183
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• 2014

Background: The purpose of study was to evaluate radiologic or clinical features of breast cancer undergoing ultrasound (US)-guided 14G core needle biopsy (CNB) and analyze the differences between underestimated and accurately diagnosed groups. Materials and Methods: Of 1,898 cases of US-guided 14G CNB in our institute, 233 cases were proven to be cancer by surgical pathology. The pathologic results from CNB were invasive ductal carcinoma (IDC) (n=157), ductal carcinoma in situ (DCIS) (n=40), high-risk lesions in 22 cases, and benign in 14 cases. Among high-risk lesions, 7 cases of atypical ductal hyperplasia (ADH) were reported as cancer and 11 cases of DCIS were proven IDC in surgical pathology. Some 29 DCIS cases and 157 cases of IDC were correctly diagnosed with CNB. The clinical and imaging features between underestimated and accurately diagnosed breast cancers were compared. Results: Of 233 cancer cases, underestimation occurred in 18 lesions (7.7%). Among underestimated cancers, CNB proven ADH (n=2) and DCIS (n=11) were diagnosed as IDC and CNB proven ADH (n=5) were diagnosed at DCIS finally. Among the 186 accurately diagnosed group, the CNB results were IDC (n=157) and DCIS (n=29). Comparison of underestimated and accurately diagnosed groups for BI-RADS category, margin of mass on mammography and US and orientation of lesion on US revealed statistically significant differences. Conclusions: Underestimation of US-guided 14G CNB occurred in 7.7% of breast cancers. Between underestimated and correctly diagnosed groups, BI-RADS category, margin of the mass on mammography and margin and orientation of the lesions on US were different.

• Journal of Magnetics
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• 제19권2호
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• pp.192-196
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• 2014

The aim of the present study was to examine the effects of high and low frequency repetitive transcranial magnetic stimulation on motor cortical excitability and the balance function in subacute stroke patients. Twenty-four subjects were randomly assigned to either the high frequency (HF) rTMS group, or the low frequency (LF) rTMS group, with 12 subjects each. All subjects received routine physical therapy. In addition, both groups performed a total of 20 sessions of rTMS for 20 minutes, once a day, 5 times per week, for a 4-week period. In the HF rTMS group, 10 Hz rTMS was applied daily to the hotspot of the lesional hemisphere; and in the LF rTMS group, 1 Hz rTMS was applied daily to the hotspot of the nonlesional hemisphere. Motor cortex excitability was determined by motor evoked potentials, and the balance function was evaluated by use of the Balance Index (BI) and the Berg Balance Scale (BBS), before and after the intervention. The change rate in the value of each variable differed significantly between the two groups (p<0.05). Furthermore, significant differences were observed between all post-test variables of the two groups (p<0.05). In the HF rTMS, significant differences were found in all the pre- and post-test variables (p<0.05). On the other hand, in the LF rTMS, significant difference was observed only between the pre- and post-test results of BI and BBS (p<0.05). The findings demonstrate that HF rTMS can be more helpful in improving the motor cortical excitability and balance function of patients with subacute stroke treatment than LF rTMS, and that it may be used as a practical adjunct to routine rehabilitation.

• Journal of Korean Neurosurgical Society
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• 제58권4호
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• pp.373-378
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• 2015

Objective : To determine the advantages of parietal approach compared to Kocher's point approach for spontaneous, oval-shaped intracerebral hemorrhage (ICH) with expansion to the parietal region. Methods : We divided patients into two groups : group A had burr holes in the parietal bone and group B had burr holes at Kocher's point. The hematoma volume, Glasgow coma scale (GCS) score, and modified Barthel Index (mBI) score were calculated. At discharge, we evaluated the patients' Glasgow outcome scale (GOS) score, modified Rankin Scale (mRS) score, motor grade, and hospitalization duration. We evaluated the patients' mBI scores and motor grades at 6 months after surgery. Results : The hematoma volume in group A was significantly less than that in group B on postoperative days 1, 3, 5, 7, 14, and 21. Group A had significantly higher GCS scores than did group B on postoperative days 1 and 3. Group A had higher mBI scores postoperatively than did group B, but the scores were not significantly different. No differences were observed for the GOS score, mRS score, motor grade at discharge, or duration of hospitalization. The mBI score of group A at 6 months after surgery was significantly higher, and more patients in group A showed muscle strength improvement. Conclusion : In oval-shaped ICH with expansion to the parietal region, the parietal approach is considered to improve the clinical symptoms at the acute phase by removing the hematoma more effectively in the early stages. The parietal approach might help promote the long-term recovery of motor power.

• 자원환경지질
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• 제15권4호
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• pp.189-204
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• 1982

The Geodo mine is located in the southern limb of the Hambaeg syncline. Geology of the area consists of Paleozoic-Mesozoic sedimentary Rocks and Cretaceous igneous rocks. The important igneous rocks presumably related to skarnization and ore mineralization in the area, are the early granodiorite and the late porphyritic granodiorite. Two mineralogical types of ore deposits are recognized in the area. They are the Fe-Cu deposits in the Myobong formation and the Au-Bi-Cu deposits in the Hwajeol formation. Contact metamorphism due to granodiorite intrusion includes hornfelsization, exoskarnization and endoskarnization. Wall-rock alterations related to the Fe mineralization are grouped into the hydrothermal replacement skarnization and the hydrothermal filling skarnization. Another hydrothermal alteration is associated with the Cu mineralization. Various mineralogical analyses have been applied for the identification of minerals. They include optical microscopy, chemical analysis, etching test, X-ray diffraction, and infrared absorption spectroscopic analyses. The ore minerals in these ore deposits are classified into two groups;hypogene and supergene minerals. Hypogene minerals consist of magnetite, pyrite, chalcopyrite, and chalcocite. Supergene minerals consist of chalcocite, bornite, and geothite. Ore minerals show various kinds of ore texture: open-space filling, exsolution, replacement, and cementation texture. The gangue minerals consist of quartz, diopside, epidote, garnet and plagioclase in the hornfelsic zone, garnet, diopside, scapolite, actinolite, sericite, chlorite, quartz, and calcite in the skarn zone, and, epidote, chlorite, sericite, quartz, and calcite in the late hydrothermal alteration zone. This study shows that the Fe-Cu deposits are of metasomatic pipe type with the later hydrothermal fillings, and the Au-Bi-Cu deposits are of hydrothermal fissure-filling type. The mineralization is probably related to the intrusion of porphyritic granite.