• 한국통신학회논문지
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• 제33권4A호
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• pp.387-393
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• 2008

본 논문에서는 TDD HSDPA(Time Division Duplex High Speed Downlink Packet Access)와 WiBro(Wireless Broadband Portable Internet) 와 같은 이동통신 규격을 지원하는 SDR(Software Defined Radio) 단말 모뎀 플랫폼을 제안한다. 제안하는 SDR 플랫폼은 DSP, FPGA, 마이크로프로세서 등 프로그래밍 가능한 소자들을 채용하여 HSDPA와 WiBro와 같은 기능을 담당하는 프로그램 등이 하드웨어 플랫폼 상에 다운로드 가능하도록 하였다. 제안하는 플랫폼은 이동통신네트워크의 멀티모드 단말시스템을 위한 물리계층 규격의 기능검증 등에 사용될 수 있다. 본 논문은 먼저 HSDPA와 WiBro 시스템의 물리계층 수신구조를 설명하고, 제안하는 SDR 플랫폼의 하드웨어 구현 방법과 각 모드에 요구되는 기능과 구현한 하드웨어 플랫폼 상에서의 최적화된 신호 흐름의 설계방법을 제시한다. 마지막으로 테스트신호를 이용한 루프백(loopback) 테스트를 통하여 제안한 SDR 플랫폼 상에 동작하는 각 모드 별 링크 성능을 보여준다. 제시된 실험 성능은 컴퓨터 시뮬레이션 성능과 비교하였다.

• 한국세라믹학회지
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• 제53권2호
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• pp.215-221
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• 2016

In this study, the utilization of the by-products of various industries was examined using raw materials of CSA high-functional cement such as coal bottom ash, red mud, phosphate gypsum, etc. Technology to improve energy efficiency and reduce $CO_2$ was developed as part of the manufacturing process; this technology included lower temperature sintering ($150{\sim}200^{\circ}C$) than is used in the OPC cement manufacturing process, replacement of CSA cement with the main raw material bauxite, and a determination of the optimum mix condition. In order to develop CSA cement, a manufacturing system was established in the Danyang plant of the HANIL Cement Co. Ltd., in Korea. About 4,200 tons of low purity expansion agent CSA cement (about 16%) and about 850 tons of the lime-based expansion agent dead burned lime (about 8%) were produced at a rate of 60 tons per hour at the HANIL Cement rotary kiln. To improve the OPC cement properties, samples of 10%, 13%, and 16% of CSA cement were mixed with the OPC cement and the compressive strength and length variation rate of the green cement were examined. When green cement was mixed with each ratio of CSA cement and OPC cement, the compressive strength was improved by about 30% and the expansibility of the green cement was also improved. When green cement was mixed with 16% of CSA cement, the compressive strength was excellent compared with that of OPC cement. Therefore, this study indicates the possibility of a practical use of low-cost CSA cement employing industrial wastes only.

• 한국임상약학회지
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• 제17권1호
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• pp.38-45
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• 2007

Background: The multitude of the therapeutic usefulness of intra-articular injection of hyaluronate on oateoarthritis of the knee is still in question. The objective of this systemic review was to elucidate both the therapeutic efficacy and the safety of intra-articular administration of hyaluronic acid for degenerative osteoarthritis of the knee joints. Methods: I searched MEDLINE and Korea Medical Database (KMbase) from January 1990 to April 2007 using a combination search terms for knee osteoarthritis and hyaluronic acid and a filter for randomized controlled trials. I extracted data on pain at rest, and during or just after movement, on joint function, and on adverse events. Results: Ten trials that reported usable quantitative information on any of the predefined end points were identified and included in the systemic review. Intra-articular injection of hyaluronic acid can decrease symptoms of osteoarthritis of the knee. The study revealed significant improvements in pain and functional outcomes with few adverse effects. However, there was significant between-study heterogeneity in the estimates of the efficacy of hyaluronic acid. Sub-group analysis showed that lower methodological quality such as a single-blind or single-center design resulted in higher estimates hyaluronic acid efficacy, and that patients older than sixty years of age and those with the most advanced radiographic stage of osteoarthritis were less likely to benefit from intra-articular injection of hyaluronic acid. Conclusion: According to the currently available evidence, intra-articular hyaluronic acid has been proven clinically effective for the patients bearing the knee osteoarthritis with NSAID-induced GI troubles or inapplicable to any surgery, and may be associated with lower risk of adverse events.

• 한국조리학회지
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• 제17권4호
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• pp.285-294
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• 2011

본 연구는 뽕나무열매인 오디를 이용하여 오디농축액을 첨가하여 일상생활에 쉽게 접하는 머핀을 제조하였다. 오디머핀의 최적화를 찾아내고 품질특성과 신제품의 가능성을 알아보고자 하였다. pH, 비중, 제품의 비체적, 색도, 기계적 품질 특성과 기호도 검사를 실시하였다. 오디 농축액 첨가량이 많을수록 pH는 낮고 비중은 감소하였다. 색도는 L, a, b값이 감소하였고 탄력성은 증가하였다. 외관은 15% 첨가군이 6.4로 가장 높은 값을 나타냈고, 나머지 시료는 5.1-5.9사이의 값으로 비슷한 기호도를 보였다. 전반적인 기호도는 20%첨가군이 가장 높은 기호도를 보였고 20% > 15% > 10% > 0% > 25%순 이었다. 오디농축액의 첨가로 품질의 저하가 있었지만 유지나 물량의 조절과 유화제의 첨가로 제품의 향상이 기대되며 15~20첨가로 기호도가 높아지리라 사료된다.

• 한국전문물리치료학회지
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• 제10권2호
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• pp.99-110
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• 2003

The purpose of this study was to analyze the effects of three different pelvic tilts on sit-to-stand ativities and to suggest a new therapeutic approach for movement reeducation in patients who have difficulty with sit-to-stand activities. The three different pelvic tilts were: (1) comfortable pelvic tilt sit-to-stand (CPT STS), (2) posterior pelvic tilt sit-to-stand (PPT STS) and (3) anterior pelvic tilt sit-to-stand (APT STS). To analyze the kinematic component of STS, a motion analysis system (Zebris) was applied to the ankle, knee, hip joint, and thigh-off area. Also, to determine the onset time of muscle contraction, surface electrodes were placed to the rectus femoris muscle (RF), the vastus lateralis muscle (VL), the biceps femoris muscle (BF), the tibialis anterior muscle (TA), the gastrocnemius muscle (GCM), and the soleus muscle (SOL). One-way repeated ANOVA was used for the statistical analysis. First, significant differences were found in kinematic variables for the hip, knee, ankle joint, and thigh-off among the three activities. Second, there was significant difference in muscle activation pattern in TA. VL. and BF among three activities. In conclusion, the findings of this study suggest the following evaluative and therapeutic approach for STS activity: (1) Changes in knee and ankle joints should be prioritized and recruitment order differences in VL and RF can be generated to accomplish abnormal STS activity. (2) APT STS can be introduced for movement efficiency and functional advantage when abnormal STS is treated.

• BMB Reports
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• 제46권11호
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• pp.527-532
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• 2013

Gangliosides are complex glycosphingolipids that are the major component of cytoplasmic cell membranes, and play a role in the control of biological processes. Human mesenchymal stem cells (hMSCs) have received considerable attention as alternative sources of adult stem cells because of their potential to differentiate into multiple cell lineages. In this study, we focus on various functional roles of gangliosides in the differentiation of hMSCs into osteoblasts or neuronal cells. A relationship between gangliosides and epidermal growth factor receptor (EGFR) activation during osteoblastic differentiation of hMSCs was observed, and the gangliosides may play a major role in the regulation of the differentiation. The roles of gangliosides in osteoblast differentiation are dependent on the origin of hMSCs. The reduction of ganglioside biosynthesis inhibited the neuronal differentiation of hMSCs during an early stage of the differentiation process, and the ganglioside expression can be used as a marker for the identification of neuronal differentiation from hMSCs.

• 대한의생명과학회지
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• 제20권3호
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• pp.156-161
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• 2014

It has been reported that safflower seeds have preventive effects against osteoporosis. Recently, safflower buds (SB) were found to have more useful functional ingredients than safflower seeds. In the current study, we evaluated the anti-osteoporosis effects of SB diet in ovariectomized (OVX) rats. The rats were divided into five groups; sham operated group, OVX alone group, OVX plus $17{\beta}$-estradiol ($E^2$ $10{\mu}g/kg$, i.p.) and OVX plus SB diet feeding group (0.3% or 1%). Feeding of SB diet (0.3% or 1%) to OVX rats markedly increased bone mineral density (BMD) of femurs, compared to the OVX group. The OVX rats exhibited a marked increase in trabecular separation (Tb.Sp) and this change was inhibited by the feeding of SB diet, similar to that seen with OVX+E2 group. Moreover, feeding of SB diet to OVX rats decreased the markers of bone turnover, including osteocalcin and alkaline phosphatase (ALP). These results suggest that SB extract has a bone sparing effect in OVX-induced trabecular bone loss and prevents deterioration of bone microarchitecture by suppressing the rate of bone turnover. Therefore, SB may be useful for preserving bone mass and structure in estrogen deficient women with a potential role in reducing postmenopausal osteoporosis.

• Journal of Plant Biotechnology
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• 제35권1호
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• pp.31-39
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• 2008

We analyzed the current research trends of living modified organisms (LMO) by questionnaires in the interest of making biosaftey laws and policies in Korea. We executed a pre-survey at the Crop Functional Genomics 2004 conference and obtained LMO research information from 423 LMO research organizations, including 32 national research institutes, 314 universities, and 77 industries. We found that the total 59 kinds of hosts including 26 kinds of plants, 15 kinds of animals, and 18 kinds of microbes were used for LMO research and E. coli was the most common host. The risk of the most experimental hosts was below a biosafety level of 1 (73.8%) and 2 (25.9%). LMO development use purpose was implemented in various developmental uses: 51.3% in test and research use, 19% in health and medical use, and 12.9% in agriculture use. The experiment product, waste product, and products of host for LMO development were 327.2, 223.6, and 13.5 in number of plants; 280.6, 52.4, and 8.7 in number of animals; and $8.3\;{\times}\;10^{11}CFU$, $7.7\;{\times}\;10^{11}CFU$, and $6.5\;{\times}\;10^{11}CFU$ in microbes in 2004. The survey results about how to possess the LMO were very unreliable, because only 10.6% of the researchers returned the questionnaires. Consequently, we strongly suggest the scientific organizations as well as scientists should have more interests in biosafety of LMO research and an LMO biosafety management system should be developed for Korea's future biotechnology.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6215-6223
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• 2015

Tyrosine phosphorylation plays an important role in regulating human physiological and pathological processes. Functional stabilization of tyrosine phosphorylation largely contributes to the balanced, coordinated regulation of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Research has revealed PTPs play an important suppressive role in carcinogenesis and progression by reversing oncoprotein functions. Receptor-type protein tyrosine phosphatase O (PTPRO) as one member of the PTPs family has also been identified to have some roles in tumor development. Some reports have shown PTPRO over-expression in tumors can not only inhibit the frequency of tumor cell division and induce tumor cell death, but also suppress migration. However, the tumor-suppression mechanisms are very complex and understanding is incomplete, which in some degree blocks the further development of PTPRO. Hence, in order to resolve this problem, we here have summarized research findings to draw meaningful conclusions. We found tumor-suppression mechanisms of PTPRO to be diverse, such as controlling G0/G1 of the tumor cell proliferation cycle, inhibiting substrate phosphorylation, down-regulating transcription activators and other activities. In clinical anticancer efforts, expression level of PTPRO in tumors can not only serve as a biomarker to monitor the prognosis of patients, but act as an epigenetic biomarker for noninvasive diagnosis. In addition, the re-activation of PTPRO in tumor tissues, not only can induce tumor volume reduction, but also enhance the susceptibility to chemotherapy drugs. So, we can propose that these research findings of PTPRO will not only support new study ideas and directions for other tumor-suppressors, importantly, but also supply a theoretical basis for researching new molecular targeting agents in the future.

• 전기전자학회논문지
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• 제24권2호
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• pp.385-391
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• 2020

배전계통에서의 과전류 및 이상 전압 현상은 전력설비에 부담을 줄 뿐만 아니라 수용가에 치명적인 피해를 입힐 수 있다. 그로 인해 실시간 배전계통 시뮬레이터를 활용하여 신속한 고장처리와 정전구간 축소 및 고장복구를 통한 전력공급의 신뢰도를 높이는 배전자동화 관련 연구가 활발히 진행되고 있다. 기존의 디지털 시뮬레이터를 이용한 배전계통 모의시스템은 고가의 설비로 시스템 구축에 제약이 있고 실 배전계통을 통한 검증 또한 불가능하다. 본 논문에서는 배전계통 디지털 시뮬레이터의 계통해석결과를 기반으로 배전자동화용 단말장치와의 연동을 통해 실시간 시뮬레이션 및 기능검증이 가능한 시스템을 개발하였다. 제안한 시스템의 효용성은 실험을 통해 검증하였다.