• ETRI Journal
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• 제37권6호
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• pp.1077-1086
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• 2015

This paper presents a general-purpose design scheme of a filter bank (FB)-based radio frequency (RF) transceiver that operates across the entire ultra-high frequency (UHF) TV band from 470 MHz to 698 MHz and complies with the TV white space (TVWS) regulatory requirements. To this end, an intermediate frequency (IF) band-pass filter (BPF) with a sharp skirt characteristic is considered as a solution for handling the incoming signals from a baseband modem. Specifically, an FB-based BPF structure with four ceramic resonator filters that effectively rejects unwanted signals is proposed to extract a desired signal in the TV band. Achievable data rates of a cognitive radio system (CRS) employing the proposed FB-based RF transceiver at the application layer are investigated in both wired and wireless environments. The service coverage of the CRS network is measured according to several modulation and coding schemes (MCSs) of the CRS. The results show that the coverage of a wireless network in a nearly open area can be extended by more than 9.3 km in the TVWS. Experimental results also confirm that the proposed FB-based RF transceiver is adequate for utilization in TVWS applications.

• 한국환경보건학회지
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• 제44권1호
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• pp.76-89
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• 2018

Background: Exposure to endocrine disrupting chemicals (EDCs) has been considered one of the main causes of a range of endocrine diseases in modern society. An EDC priority list considering exposure, toxicity, and societal concern should be established for EDC management. Methods: The chemical ranking and scoring (CRS) system for EDCs was based on exposure, toxicity,and societal concern. The exposure score system was based on usage, circulation volume, bioaccumulation, and detection in consumer products. The toxicity score system was based on carcinogenicity and reproductive and developmental toxicity. The societal concern score system was based on domestic or international regulations and mass media reports. Results: A total of 165 EDCs were considered in the CRS system. The top-five priority EDCs were Bis(2-ethylhexyl) phthalate (DEHP), Benzene, Bisphenol A, Dibutyl phthalate (DBP) and Trichloroethylene. Phthalates, bisphenols and parabens were identified as priority chemical groups. Conclusion: We developed a CRS system for EDCs to identify priority EDCs for management. This will be a foundation to provide an EDC management plan based on scientific decision-making.

• Journal of Digestive Cancer Research
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• 제10권2호
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• pp.74-81
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• 2022

Colorectal peritoneal metastasis has been an incurable disease for centuries. However, since the new millennium, recent advancements in therapies are achieved with modern chemotherapeutic agents, target agents, and immune checkpoint blockade introduction. Modern chemotherapies, from a nearly nonexistent median survival if untreated, have raised the duration to 16 months with target agents. Experts have once again surpassed its limit by introducing intraperitoneal chemotherapy and cytoreductive surgery (CRS). Numerous clinical trials regarding CRS and hyperthermic intraperitoneal chemotherapy have now opened new doors in peritoneal carcinomatosis treatment, even securing complete remission. In addition, up-to-date modalities, such as pressurized intraperitoneal aerosol chemotherapy and immunotherapies, showed promising results at an early stage.

• Journal of the Korean Data and Information Science Society
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• 제26권3호
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• pp.669-675
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• 2015

본 연구는 사육방식의 차이가 한우 등심내 콜티졸과 지방산함량에 미치는 영향을 구명하고자 실시하였다. 무항생제 및 관행축산으로 생산된 한우육 1등급 등심 부위를 3종류의 브랜드별로 각각 3회씩 총 18점을 구매하여 시료로 공시하였고, 분석한 결과는 다음과 같다. 한우육 등심내 콜티졸 함량은 무항생제 처리구에서 관행사육 처리구 대비 유의적 (p=0.0176)으로 낮게 나타났으며, 포화지방산 및 불포화지방산 함량에서는 유의적 (p >0.05)인 차이를 나타내지는 않았으나, 관행사육 처리구에서는 포화지방산이, 무항생제 처리구에서는 불포화지방산이 각각 높은 경향으로 분석되었다. 또한, 불포화지방산 중 n-3과 n-9 지방산을 제외한 n-6 지방산에서 유의적 (p <0.01)인 차이를 보였다. 또한, 한우 등심내 콜티졸 농도와 n-6 지방산 농도간의 상관관계를 분석한 결과 유의적 (p=0.0014)으로 부 (-)의 상관관계가 성립되었다.

• Journal of Ginseng Research
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• 제42권1호
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• pp.107-115
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• 2018

Background: Depression is one of the most commonly diagnosed neuropsychiatric diseases, but the underlying mechanism and medicine are not well-known. Although Panax ginseng has been reported to exert protective effects in various neurological studies, little information is available regarding its antidepressant effects. Methods: Here, we examined the antidepressant effect and underlying mechanism of P. ginseng extract (PGE) in a chronic restraint stress (CRS)-induced depression model in mice. Results: Oral administration of PGE for 14 d decreased immobility (depression-like behaviors) time in forced swim and tail suspended tests after CRS induction, which corresponded with attenuation of the levels of serum adrenocorticotropic hormone and corticosterone, as well as attenuated c-Fos expression in the amygdala. PGE enhanced messenger RNA expression level of brain-derived neurotrophic factor but ameliorated microglial activation and neuroinflammation (the level of messenger RNA and protein expression of cyclooxygenase-2 and inducible nitric oxide synthase) in the amygdala of mice after CRS induction. Interestingly, 14-d treatment with celecoxib, a selective cyclooxygenase-2 inhibitor, and $N_{\omega}$-nitro-L-arginine methyl ester hydrochloride, a selective inducible nitric oxide synthase inhibitor, attenuated depression-like behaviors after CRS induction. Additionally, PGE inhibited the upregulation of the nuclear factor erythroid 2 related factor 2 and heme oxygenase-1 pathways. Conclusion: Taken together, our findings suggest that PGE exerts antidepressant-like effect of CRS-induced depression by antineuroinflammatory and antioxidant (nuclear factor erythroid 2 related factor 2/heme oxygenase-1 activation) activities by inhibiting the hypothalamo-pituitary-adrenal axis mechanism. Further studies are needed to evaluate the potential of components of P. ginseng as an alternative treatment of depression, including clinical trial evaluation.

• 한국전자파학회논문지
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• 제25권10호
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• pp.1062-1068
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• 2014

본 논문에서는 두 개의 순차적인 inverse synthetic aperture radar(ISAR) 영상들을 활용하여 표적의 회전 속도(Rotation Velocity: RV) 추정을 통한 수직 거리 스케일링(cross-range scaling: CRS)을 수행한다. 순차적으로 형성된 두 개의 ISAR 영상들에 각각 scale invariant feature transform(SIFT)를 적용함으로써 관측각도의 변화에 강인한 산란원(scatterer)들을 추출한다. 추출된 산란원과 각 영상 내 표적의 회전 중심(Rotation Center: RC) 사이의 거리가 같다는 점을 이용하여 비용함수(cost function)를 설정한 후, 전역 탐색 기법(exhaustive search method)과 결합된 particle swarm optimization(PSO)의 최적화를 통해 표적의 RV를 RC 정보 없이 추정한다. 시뮬레이션에서는 시나리오 기반으로 기동하는 표적에 대한 ISAR 영상 형성 후, 제안된 기법을 통해 RC의 정보 없이 RV를 추정함으로써 ISAR 영상의 CRS가 성공적으로 수행됨을 보여준다.

• 한국항해항만학회지
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• 제30권4호
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• pp.267-275
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• 2006

Due to the growth of container traffic and port competition, ports have increasingly been under pressure to improve their efficiency in port operation and port management for competitive edge. The purpose of this study is to compare the technical efficiency among major container terminals in China, Korea and Singapore using Data Envelopment Analysis (DEA). This paper analyses the returns-to-scale using the output orientation of VRS and CRS model. The benefits of this study examining the relative performance of container terminals will enable container terminal operating companies or port policy makers in those countries to identify current slacks and to set up a proper port management and operation plan to improve their productivity.

• 한국멀티미디어학회논문지
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• 제22권8호
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• pp.940-949
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• 2019

Classroom response systems (CRS) have been proven to have positive educational effects on student engagement and participation by allowing immediate feedback to both students and instructors. We explore the use of a chatbot and slide widget-based CRS to overcome some of the challenges of existing mobile-based CRSs while retaining their advantages. Our system uses widely available instant messaging services and operates web-based slide widgets that can be seamlessly integrated into instructors' slides to visualize student feedback in various formats. The student survey results indicate that our system is as effective as conventional CRSs in promoting student engagement and participation.

• Journal of Multimedia Information System
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• 제6권1호
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• pp.37-42
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• 2019

Skyline queries are used in a variety of fields to make optimal decisions. However, as the volume of data and the dimension of the data increase, the number of skyline points increases with the amount of time it takes to discover them. Mainly, because the number of skylines is essential in many real-life applications, various studies have been proposed. However, previous researches have used the k-parameter methods such as top-k and k-means to discover representative skyline points (RSPs) from entire skyline point set, resulting in high query response time and reduced representativeness due to k dependency. To solve this problem, we propose a new Connected Component Clustering based Representative Skyline Query (3CRS) that can discover RSP quickly even in high-dimensional data through connected component clustering. 3CRS performs fast discovery and clustering of skylines through hash indexes and connected components and selects RSPs from each cluster. This paper proves the superiority of the proposed method by comparing it with representative skyline queries using k-means and DBSCAN with the real-world dataset.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제24권2호
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• pp.238-243
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• 2021

Caudal regression syndrome (CRS) is a rare neural tube defect that affects the terminal spinal segment, manifesting as neurological deficits and structural anomalies in the lower body. We report a case of a 31-month-old boy presenting with constipation who had long been considered to have functional constipation but was finally confirmed to have CRS. Small, flat buttocks with bilateral buttock dimples and a short intergluteal cleft were identified on close examination. Plain radiographs of the abdomen, retrospectively reviewed, revealed the absence of the distal sacrum and the coccyx. During the 5-year follow-up period, we could find his long-term clinical course showing bowel and bladder dysfunction without progressive neurologic deficits. We present this case to highlight the fact that a precise physical examination, along with a close evaluation of plain radiographs encompassing the sacrum, is necessary with a strong suspicion of spinal dysraphism when confronting a child with chronic constipation despite the absence of neurologic deficits or gross structural anomalies.