• 융합신호처리학회논문지
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• 제13권2호
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• pp.99-105
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• 2012

본 논문은 직교주파수 분할 다중접속 시스템 (Orthogonal Frequency-division Multiple Access: OFDMA)에서 계산 효율적인 동적 부반송파 할당 (Dynamic subcarrier allocation :DSA) 기법을 제안하였다. 제안된 DSA 기법은 계산량을 크게 줄일 수 있을 뿐 아니라 전체 Channel quality information (CQI)를 전송하는 Amplitude Craving Greedy (ACG) 기법에 비해 CQI 정보량도 줄일 수 있다. 하지만 제안된 기법의 성능은 ACG 기법과 거의 유사하게 나타난다. 또한, 신호 대 잡음비에 기반한 대역폭 할당기법 (Bandwidth assignment based on the signal-to-noise ratio: BABS) 개선한 대역폭 할당기법을 제안하였다. 개선된 BABS 기법은 제안된 DSA 기법과 결합되어 기존 기법에 비해 더욱 높은 아웃티지 성능 이득을 나타낸다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권1호
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• pp.72-81
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• 2019

Objective: To determine the effect of gut pH and rumen microbial fermentation on glycerol encapsulated in alginate and alginate-chitosan polymers. Methods: Glycerol was encapsulated at 2.5%, 5%, 7.5%, or 10% (w/w) with sodium alginate (A) and alginate-chitosan (AC) polymers. Surface morphology and chemical modifications of the beads were evaluated using scanning electron microscopy and Fourier transform infrared (FTIR) spectra. Encapsulation efficiency was determined at the 5% glycerol inclusion level in two experiments. In experiment 1, 0.5 g of alginate-glycerol (AG) and alginate-chitosan glycerol (ACG) beads were incubated for 2 h at $39^{\circ}C$ in pH 2 buffer followed by 24 h in pH 8 buffer to simulate gastric and intestinal conditions, respectively. In experiment 2, 0.5 g of AG and ACG beads were incubated in pH 6 buffer at $39^{\circ}C$ for 8 h to simulate rumen conditions. All incubations were replicated four times. Free glycerol content was determined using a spectrophotometer and used to assess loading capacity and encapsulation efficiency. An in vitro experiment with mixed cultures of rumen microbes was conducted to determine effect of encapsulation on microbial fermentation. Data were analyzed according to a complete block design using the MIXED procedure of SAS (SAS Institute, Cary, NC, USA). Results: For AG and ACG, loading capacity and efficiency were 64.7%, 74.7%, 70.3%, and 78.1%, respectively. Based on the FTIR spectra and scanning electron microscopy, ACG treatment demonstrated more intense and stronger ionic bonds. At pH 6, 36.1% and 29.7% of glycerol was released from AG and ACG, respectively. At pH 2 minimal glycerol was released but pH 8 resulted in 95.7% and 93.9% of glycerol released from AG and ACG, respectively. In vitro microbial data show reduced (p<0.05) fermentation of encapsulated glycerol after 24 h of incubation. Conclusion: The AC polymer provided greater protection in acidic pH with a gradual release of intact glycerol when exposed to an alkaline pH.

• KSBB Journal
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• 제11권1호
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• pp.77-85
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• 1996

에탄올 생산 효모균주인 Saccharomyces K35의 에탄올 생산을 위한 최적의 초기 pH는 5.0으로 나 타났으며, 기질로 200g/$\ell$ 의 glucose를 이 용했을때 약 80%의 수율을 나타내어 내당성도 좋은 것으로 나타났다. 첨가제와 가교제로서 Celite R-634 1.67 %(v/v) 와 glutaraldehyde 1.67% (v/v) 를 함께 첨가했을때(ACG bead) Ca-alginate bead에 비해 안정성, 에탄올 생산성 빛 세포생존률이 좋게 나타 났다. 또한 배지밖에서 자란 효모 농도도 감소하여 A A CG bead가 Ca-alginate bead보다 phosphate이 온에 더 안정한 것으로 보인다. SEM (Scanning E Electron Microscopy)을 통해 ACG gel bead의 구조를 관찰하였는데 , ACG bead가 Ca~alginate bead에 비해 훨씬 온전한 모습을 유지하며, 효모의 농도가 상당히 밀집되어 있음을 보여준다. 반복회분 식 배양을 시도했을때 Ca-alginate bead의 경우는 7회분(약 40일)까지는 에탄올 놓도와 효모농도가 각각 138g/$\ell$-gel와 29~30g/$\ell$-gel을 유지하다가 급격히 감소하는 경향을 보였으나, ACG bead의 경 우에는 130~150g/$\ell$-gel와 32~35g/$\ell$-gel의 수준을 유지하였으며, 세포생존률도 약 70% 이상을 유지하였다.

• 한국통신학회논문지
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• 제31권6A호
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• pp.617-626
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• 2006

본 논문에서는 OFDMA 시스템 하향 링크에서 섹터 Throughput을 향상시키기 위하여, 모든 사용자의 채널 상태를 고려하여 동적 채널 할당을 진행하는 ASA(Aggressive Subchannel Allocation) 알고리즘을 제안한다. 그리고 제안한 알고리즘을 섹터 별 Frequency Reuse Factor 가 1인 2-tier 환경 하에서 Round Robin, ACG(Amplitude Craving Greedy), RCG(Rate Craving Greedy) 그리고 GPF(General Proportional Fair) 알고리즘과 함께 모의실험을 통하여 각 알고리즘의 성능을 분석한다. 그 결과 본 논문에서 제안한 ASA 알고리즘이 Round Robin 보다는 58 %, ACG 보다는 190 %, RCG 보다는 130 % 그리고 GPF보다는 8.5 % 높은 Sector Throughput을 보인다.

• 대한방사선기술학회지:방사선기술과학
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• 제4권1호
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• pp.37-44
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• 1981

It is a experimental report to investigate optimum exposure technics in angiocardiography. Because of x-ray absorption and rapid voluntary motion in the heart region, it bound that discrimination ability of the exposed film is being decreased in ACG To circumvent these disadvantage it must be necessary to use short time exposure technics and also high capacity equipment in ACG. But in the case of using the low tube voltage to improve contrast on the exposed film, it will be result in a many difficulties in interpretation of the image due to increased contrast in vertebral images. Therefore the ranges 80 kVp to 90 kVp of could be suitable for the purpose of good contrast and an excellent discrimination ability and under this circumstance the optimum grid ratio for ACG was 8:1 to 12:1.

• Journal of Yeungnam Medical Science
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• 제40권4호
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• pp.381-387
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• 2023

Background: Frailty is defined as a condition of being weak and delicate, and it represents a state of high vulnerability to adverse health outcomes. Recent studies have suggested that the cingulate gyrus is associated with frailty in the elderly population. However, few imaging studies have explored the relationship between frailty and the cingulate gyrus in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Methods: Eighteen right-handed patients with ESRD undergoing hemodialysis were enrolled in the study. We used the FreeSurfer software package to estimate the cortical thickness of the regions of interest, including the rostral anterior, caudal anterior, isthmus, and posterior cingulate gyri. The Beck Depression Inventory, Beck Anxiety Inventory, and laboratory tests were also conducted. Results: The cortical thickness of the right rostral anterior cingulate gyrus (ACG) was significantly correlated with the Fried frailty index, age, and creatinine level. Multiple regression analysis indicated that the cortical thickness of the right rostral ACG was associated with frailty after controlling for age and creatinine level. Conclusion: Our results indicate that the cortical thickness of the rostral ACG may be associated with frailty in patients with ESRD on hemodialysis and that the rostral ACG may play a role in the frailty mechanism of this population.

• Archives of Plastic Surgery
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• 제45권4호
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• pp.384-387
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• 2018

Blepharoplasty is one of the most commonly performed aesthetic procedures. Surgical complications are rare, but can have severe consequences, such as permanent vision loss. In this report, we describe a patient who developed primary angle-closure glaucoma (ACG) with associated vision loss after a oculoplastic procedure using local anesthesia. So far, six similar cases have been described in the literature. It is believed that acute ACG is triggered by the surgical procedure in patients with predisposing risk factors such as a cataract. Surgical triggering factors include the use of buffered lidocaine/xylocaine with adrenaline/epinephrine, stress, and coverage of the eyes postoperatively. Due to postoperative analgesic use, the clinical presentation can be mild and atypical, leading to a significant diagnostic delay. Acute ACG should therefore be excluded in each patient with postoperative complaints by assessing pupillary reactions. If a fixed mid-wide pupil is observed in an ophthalmologic examination, an immediate ophthalmology referral is warranted. Surgeons should be aware of this rare complication in order to offer treatment at an early stage and to minimize the chance of irreversible vision loss.

• 미생물학회지
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• 제24권2호
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• pp.79-85
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• 1986

A. nidulans의 $tRNA^{Arg}$의 염기순서를 효소절단 방법으로 결정하였다. 이 방법으로 염기순서를 결정한 결과 다음과 같았다. 5'GGCCGGCUGGCCCAAXUGGCAAGGCXUCUGAXUACGAAXCAGGAGAUUGCAXXXXXGAGCXXUXXGUCGGUCACCA3'. 위의 결과로 플로버잎 구조를 만들어본 결과 안티코돈이 ACG인 $tRNA^{Arg}$으로 판명되었고. 이 결과는 아미노산 부하검사(charging test)의 결과와 일치하였다. 이 tRNA의 유천자의 염기순서 결과와 비교하여 염기순서의 정확성을 검증하였고, minor base분석을 통하여 전 염기순서를 추정하였다.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2009년도 심포지엄 및 춘계학술발표회
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• pp.289-290
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• 2009

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6225-6229
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• 2015

Faecal pH and cholate are two important factors that can affect colon tumorigenesis, and can be modified by diet. In this study, the effects of two Chinese traditional cooking oils (pork oil and canola/rapeseed oil) on the pH and the cholic acid content in feces, in addition to colon tumorigenesis, were studied in mice. Kunming mice were randomized into various groups; negative control group (NCG), azoxymethane control group (ACG), pork oil group (POG), and canola oil Ggroup (COG). Mice in the ACG were fed a basic rodent chow; mice in POG and COG were given 10% cooking oil rodent chow with the respective oil type. All mice were given four weekly AOM (azoxymethane) i.p. injections (10mg/kg). The pH and cholic acid of the feces were examined every two weeks. Colon tumors, aberrant crypt foci and organ weights were examined 32 weeks following the final AOM injection. The results showed that canola oil significantly decreased faecal pH in female mice (P<0.05), but had no influence on feces pH in male mice (P>0.05). Pork oil significantly increased the feces pH in both male and female mice (P<0.05). No significant change was found in feces cholic acid content when mice were fed 10% pork oil or canola oil compared with the ACG. Although Kunming mice were not susceptible to AOM-induced tumorigenesis in terms of colon tumor incidence, pork oil significantly increased the ACF number in male mice. Canola oil showed no influence on ACF in either male or female mice. Our results indicate that cooking oil effects faecal pH, but does not affect the faecal cholic acid content and thus AOM-induced colon neoplastic ACF is modified by dietary fat.