• 한국지리정보학회지
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• 제18권2호
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• pp.135-148
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• 2015

본 연구는 LiDAR DEM(Digital Elevation Model)과 다중시기에 촬영된 Landsat 영상을 이용하여 4대강 정비사업이 시행되기 이전 및 이후에 낙동강 유역 내 발생한 토지피복 변화를 탐지 및 분석하기 위하여 수행되었다. 우선 LiDAR DEM으로부터 추출된 제방경계선을 이용하여 하천유역 폴리곤을 생성하고, 하천유역 폴리곤을 이용하여 다중시기에 촬영된 Landsat-5 TM(Thematic Mapper) 영상과 Landsat-8 OLI(Operational Land Imager) 영상으로부터 4개의 하천유역 영상을 각각 추출하였다. 그리고 영상분류방법을 적용하여 각 하천유역 영상으로부터 하천유역의 주요 토지피복인 하천, 나지, 초지를 각각 분류하였고, 전체 면적에서 각 토지피복이 차지하는 비율을 계산하였다. 다중시기에 촬영된 하천유역 영상으로부터 분류된 각 토지피복의 변화량을 분석한 결과, 4대강 정비사업이 시행되기 이전과 4대강 정비사업이 완공된 이후에는 계절의 변화에 의해 나지와 초지의 면적은 큰 폭으로 변화하였으나, 하천의 면적은 큰 변화가 없었다. 반면에 4대강 정비사업 전후로, 낙동강 유역 내 저수량의 증가로 인해 하천의 면적이 큰 폭으로 증가하였다. 본 논문은 LiDAR DEM과 4대강 정비사업 이전과 이후에 촬영된 위성영상들을 이용하여 4대강 정비사업으로 인해 발생한 하천 유역 내 토지피복 변화를 탐지할 수 있는 효과적인 방법을 제시하였다는데 의의가 있다.

• Korean Journal of Radiology
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• 제24권7호
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• pp.681-689
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• 2023

Objective: Three-dimensional rotational angiography (3D-RA) is increasingly used for the evaluation of intracranial aneurysms (IAs); however, radiation exposure to the lens is a concern. We investigated the effect of head off-centering by adjusting table height on the lens dose during 3D-RA and its feasibility in patient examination. Materials and Methods: The effect of head off-centering during 3D-RA on the lens radiation dose at various table heights was investigated using a RANDO head phantom (Alderson Research Labs). We prospectively enrolled 20 patients (58.0 ± 9.4 years) with IAs who were scheduled to undergo bilateral 3D-RA. In all patients' 3D-RA, the lens dose-reduction protocol involving elevation of the examination table was applied to one internal carotid artery, and the conventional protocol was applied to the other. The lens dose was measured using photoluminescent glass dosimeters (GD-352M, AGC Techno Glass Co., LTD), and radiation dose metrics were compared between the two protocols. Image quality was quantitatively analyzed using source images for image noise, signal-to-noise ratio, and contrast-to-noise ratio. Additionally, three reviewers qualitatively assessed the image quality using a five-point Likert scale. Results: The phantom study showed that the lens dose was reduced by an average of 38% per 1 cm increase in table height. In the patient study, the dose-reduction protocol (elevating the table height by an average of 2.3 cm) led to an 83% reduction in the median dose from 4.65 mGy to 0.79 mGy (P < 0.001). There were no significant differences between dose-reduction and conventional protocols in the kerma area product (7.34 vs. 7.40 Gy·cm², P = 0.892), air kerma (75.7 vs. 75.1 mGy, P = 0.872), and image quality. Conclusion: The lens radiation dose was significantly affected by table height adjustment during 3D-RA. Intentional head off-centering by elevation of the table is a simple and effective way to reduce the lens dose in clinical practice.

• Ocean Science Journal
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• 제40권4호
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• pp.191-200
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• 2005

In this study an analytical tide model of uniform width with three sub-regions is presented. The three-subregions model takes into account step-like variations in depths in the direction of the channel as a way to examine the $M_2$ tide of the East China Sea (ECS) as well as the Yellow Sea (YS). A modified Proudman radiation condition has been applied at the northern open head, while the sea surface elevation is specified at the southern open boundary. It is seen that, due to the presence of an abrupt change in depth, co-amplitude lines of the $M_2$ tide are splitted to the east and west near the end of the ECS shelf region. Variations in depths, bottom friction and the open head boundary conditions all contribute to the determination of formation of amphidromes as well as overall patterns of $M_2$ tidal distribution. It is seen that increasing water depth and bottom friction in the ECS shelf results in the westward shift of the southern amphidrome. There is however no hint at all of the well-known degenerated tidal pattern being formed. It is inferred that a lateral variation of water depth has to be somehow incorporated to represent the tidal patterns in ECS in a realistic manner. Regarding the radiation factor introduced by Fang et al. (1991), use of a value larger than one, possibly with a phase shift, appears to be a proper way of incorporating the reflected waves from the northern Yellow Sea (NYS).

• 한국지리정보학회지
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• 제18권4호
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• pp.131-144
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• 2015

본 연구에서는 Unity 3D를 활용한 강우레이더 관측정보 시각화 시스템 프로토타입 구축에 관 해 서술하였다. 레이더 정보의 효율적 가시화를 통한 사용자 정보제공을 위해서는 지형정보와의 융합이 필수적이다. 하지만 방대한 양의 레이더 관측정보와 대용량 지형정보를 매쉬업하여 서비스 하는 것은 데이터 처리에 있어 과부하가 발생하여 서비스 수준이 낮아지는 경향이 있다. 특히 위 성영상, DEM 등을 활용한 3차원 지형정보는 그 자체만으로도 대용량 정보로 분류되고 있어서 신 속한 서비스 구현을 위해 비교적 용량이 가벼운 2차원 정보를 활용하는 것이 일반적이다. 본 연구 는 이러한 부분을 개선하고자 최근 모바일 게임분야에서 활발히 활용중인 Unity 3D 엔진을 사용 하였다. 또한, 대용량 위성이미지 분할기법, 이미지 텍스쳐 Layer 매쉬업 기법 등을 고안하여 3차 원 지형기반으로 서비스 할 수 있는 시각화 시스템 프로토타입을 구축하였다. 본 프로토타입 구축 을 통해 향후 전 국토에 분포된 기상관측 레이더 네트워크망 데이터를 입체적 지형 기반의 직관적 정보로 제공함으로써 강우와 관련된 방재업무 분야에 효율적 활용이 가능할 것으로 기대한다.

• Journal of Chest Surgery
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• 제30권8호
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• pp.809-814
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• 1997

마약성 진통제와 국소마취제에 의한 지속적 경막외마취는 개흉술후 통증감소를 위한 방법으로 널리 사용되고 있다. 본 연구에서는 지난 1994년 1월부터 1995년 7월까지 본원 흉부외과에서 츠방 혹은 후측방 개흉술을 받은 환자 38명을 대상으로 19명씩 실험군과 대조군으로 구분하여 실험군에 경막외마취를 시행하여 그 효과를 조사하였다. 먼저 lidocaine과 norphine을 섞어 경막서 지속적 외도관을 통해 주사하고 그후 bupivacaine과 morphine을 섞어 술후 5∼6일간 지속투여를 하였다. 대조군에 비해 실험군에서 환자의 통증수치와 상지거상능력과 호흡수는 주사추 30분부터 통계적으로 의미 있게 변화되어 술후 통증이 경감되고 있음을 알 수 있었고, 말초동맥혈 이산화탄소분압은 2시간 후부터 통계적으로 의미 있게 줄어들어 환자가 효과적인 호흡을 하고 있음을 알 수 있었다. 술후 재원기간도 의미 있게 줄어들었다. 경막외마취의 주요한 합병증으로는 뇨정체가 있었으나 심각하지는 않았다. 이상의 결과로 우리는 개흉술후 경막외마취가 우수한 통증완화 효과가 있어 술후 폐합병증을 예방하고 술후 빠른 회복에도 좋은 영향을 미치는 것으로 생각한다.

• Korean Journal of Radiology
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• 제20권5호
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• pp.830-843
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• 2019

Objective: To examine the potential of intravoxel incoherent motion (IVIM) and blood oxygen level-dependent (BOLD) magnetic resonance imaging for detecting renal changes after iodinated contrast-induced acute kidney injury (CI-AKI) development in a diabetic rabbit model. Materials and Methods: Sixty-two rabbits were randomized into 2 groups: diabetic rabbits with the contrast agent (DCA) and healthy rabbits with the contrast agent (NCA). In each group, 6 rabbits underwent IVIM and BOLD imaging at 1 hour, 1 day, 2 days, 3 days, and 4 days after an iohexol injection while 5 rabbits were selected to undergo blood and histological examinations at these specific time points. Iohexol was administrated at a dose of 2.5 g I/kg of body weight. Further, the apparent transverse relaxation rate (R2^*), average pure molecular diffusion coefficient (D), pseudo-diffusion coefficient (D^*), perfusion fraction (f) were calculated. Results: The D and f values of the renal cortex (CO) and outer medulla (OM) were significantly decreased compared to baseline values in the 2 groups 1 day after the iohexol injection (p < 0.05). A marked reduction in the D^* values for both the CO and OM was also observed after 1 hour in each group (p < 0.05). In the OM, a persistent elevation of the R2^* was detected for 4 days in the DCA group (p < 0.05). Histopathological changes were prominent, and the pathological features of CI-AKI aggravated in the DCA group until day 4. The D, f, and R2^* values significantly correlated with the histological damage scores, hypoxia-inducible transcription factor-1α expression scores, and serum creatinine levels. Conclusion: A combination of IVIM and BOLD imaging may serve as a noninvasive method for detecting and monitoring CI-AKI in the early stages in the diabetic kidney.

• 동의생리병리학회지
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• 제16권1호
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• pp.154-159
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• 2002

There are several types of salts that can be classified into raw salt(Chunil salt), purified salts(NaCl reagent grade) and processed salts(Bamboo salt, Purple bamboo salt using in this study) in Korea. Salts has been utilized for the food as well as for the drug in the Oriental Medicine. Purple bamboo salt(PB-salt) was made by heating up to 1300℃ nine times after putting the raw salts in the bamboo. Since salt is generally known to cause the blood pressure to elevate, this study was conducted to investigate the effect of PB-salt on an adverse reaction of the blood pressure elevation. The experiment was performed with the 2 protocols ; 1. Effect of NaCl and PB-salt administration i.v. with the different the concentration(250, 500, 750, 1000mg/kg) on a mean artery blood pressure(MAP) change. 2. Effect of 500mg/kg NaCl and PB-salt administration p.o. for 6 days on the systolic blood pressure change. The results were as follows; The results were as follows; In a short minute change of blood pressure by direct method, PB-salt adminstration did not induced the hypertension unlike NaCl adminstration. In a date change of blood pressure by indirect method, systolic blood pressure was increased about 12-18% in the NaCl administration group, whereas within 6% in the PB-salt administration group from 2 days to 5 days. These results suggest that PB-salt might have some unidentified ingredient to be changed in the course of processing, making it superior to other salts.

• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7837-7841
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• 2015

Objective: To assess the safety of Liena polypeptide injection (produced by JILIN FSENS PHARMACEUTICAL CO.,LTD) combined with chemotherapy in treating patients with advanced cancers. Method: A consecutive cohort of patients with advanced cancers were treated with Liena polypeptide injection combined with chemotherapy. And chemotherapy for patients with advanced cancers were adopted from regimens suggested by NCCN guideline. Liena polypeptide injection was intravenously injected at a dosage of 2ml plus 100ml normal saline for continuous 7 days during chemotherapy as one course. After at least two courses of treatment, safety and side effects were evaluated. Results: There were 20 female and 14 male patients with advanced cancer recruited into this study, including 10 patients with breast, 8 patients with colorectal, 8 patients with lung, 4 patients with gastric, and 1 patient with esophageal cancer, as well as 1 patient with non-Hodgkin's lymphoma, 1 patient with low pharyngeal and 1 patient with urethral cancer. The median age of patients was 59 (40-82) years. Incidences of Grade 1 to 2 myelosuppression was observed in 5/34 patients, and Grade 1 to 2 elevation of hepatic enzyme was recorded in 3/34 patients. Adverse effects on the gastrointestinal tract were documented in 5/34 patients, and were Grade 1. No Grade 3-4 toxicities were diagnosed. No treatment related death was found. Conclusions: Liena polypeptide injection combined with chemotherapy was safe in treating several sites of tumors, that mainly included lung, colorectal and breast cancer. However, further study should be conducted to clarify the effectiveness of this treatment.

• Journal of Ginseng Research
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• 제35권2호
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• pp.129-137
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• 2011

The antioxidant activities of fermented red ginseng (FRG) were investigated in vitro and in vivo. The contents of total polyphenol and total flavonoid in FRG extracts were $17.01{\pm}2.00$ ${\mu}g/mg$ and $18.42{\pm}3.97$ ${\mu}g/mg$, respectively. These extracts were capable of directly scavenging ${\alpha}$, ${\alpha}$-diphenyl-picrylhydrazyl free radicals. The antioxidative effects of the FRG extracts in streptozotocin (STZ)-induced diabetic rats were also investigated. The activities of plasma alanine transaminase, aspartate transaminase, and ${\gamma}$-glutamyltransferase were significantly decreased by extract administration as compared to an STZ control group. Hepatic glutathione content depleted by STZ treatment was significantly increased by treatment of the FRG extracts, but the elevation of lipid peroxide content induced by STZ was significantly decreased by the extracts. Activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase decreased after STZ-treatment were recovered by the treatment of the FRG extracts. These results indicate that FRG extracts have antioxidative effets in STZ-induced diabetic rats.

• 한국건축시공학회지
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• 제24권2호
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• pp.227-238
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• 2024

본 연구에서는 최근 이상기후로 인해 양극화된 기후 패턴으로 인한 침수 피해가 증가하고 있으며, 그 해결책이 빗물 침투저류블록이라고 설명하고 있다. 또한, 기존 프로그램의 한계점으로 드론 기술과 결합된 새로운 기능이 필요함을 제안하며, 저류조 기능을 가진 빗물침투저류블록의 최적 설치 장소 선정을 목표로 하는 침수·범람 시뮬레이션 기술 개발에 대한 실험 및 평가를 진행한다. 실제 빗물침투저류블록이 실시공된 지역을 대상으로 평가를 진행하였으며, DEM과 DSM을 통한 기존 프로그램과의 비교, 침수·범람 시뮬레이션 프로그램의 실현장 적용성 검토의 2개 항목을 통해 평가를 진행하였으며, 그 결과, 침수·범람 시뮬레이션 프로그램의 실무에 적용함으로써 빗물침투저류블록의 설치 시 최적지 선정을 위한 의사결정 도구로 활용할 수 있다는 것을 확인하였다.