• Journal of Broadcast Engineering
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• v.4 no.2
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• pp.103-118
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• 1999

This paper analyzes the performance of symbol timing recovery and equalizer in 8VSB digital terrestrial TV receiver under various multipath signals and proposes equalization techniques which improve indoor reception performance. Data segment sync is used for symbol timing recovery and timing offset is measured for echoes of various delays and amplitudes by using symbol timing detection filter whose pattern is +1. +1. -1. and -1. Measured timing offsets were below 10% for long echoes with more than 5 symbol delay and above 30% for short echoes with around 1 symbol delay. Indoor reception is always more challenging than outdoor reception due to lower signal strength. large and short multipaths. and moving interfering objects. So it is considered to use FSE (Fractionally Spaced Equalizer) which is very robust to timing offset and blind equalizer which can update equalizer tap coefficients even by information data. We compare the performance of conventional DFE (Decision Feedback Equalizer) and FSE-DFE using LMS algorithm and Stop and Go algorithm for the indoor reception. Experiments reveals FSE has excellent performance for large timing offset and Stop and Go algorithm shows good performance for Doppler shift. so we propose to use FSE-DFE structure with Stop and Go algorithm for the reliable indoor reception.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.123-131
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• 2018

The objective of this study was to evaluate the effect of roasting degree of barley on aroma characteristics of boricha (barley tea) using solvent-assisted flavor evaporation-gas chromatography-mass spectrometry and gas chromatography-olfactometry. Fifteen volatile compounds including pyrazine, ethylpyrazine, butyrolactone, and guaiacol were considered important volatile compounds, which are generated by roasting barley, because concentrations of those volatiles were significantly increased (p<0.05) as roasting degree of barley was darker. Guaiacol (smoky), furfuryl alcohol (burnt sugar), and furfural (caramel) were detected as aroma-active compounds of boricha with high intensity. Aroma intensity of aroma-active compounds in boricha increased with increase in roasting degree of barley. However, one unknown compound with burnt smell was detected as off-flavor in dark roasted barley. Therefore, it is implied that medium roasting of barley is desirable during boricha manufacturing. Furthermore, boricha manufactured with steamed barley contained more abundant volatile flavor compounds, which may lead to better aroma quality of boricha.

• International Journal of Highway Engineering
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• v.14 no.1
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• pp.35-43
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• 2012

The Government is implementing the safety measures for pedestrian in living zone to decrease the traffic accident casualties in half. It is urgently to study the guideline because it contains to make the guideline of a median strip in City to prevent the violation of central line and jaywalking on the main contents. So, this study analyzed the pedestrian accidents and the violation of central line, and studied the type of a median strip, the installation guideline through studying the minimum crossing. Consequently, this study found out that a median strip which revised the attention inducement stick to decrease jaywalking could not have the strong prevention function of a crash barrier, so if it happens separation after the collision between vehicles, it induced the secondary accidents, and could take negative effects on traffic safety. In consideration of driving safety, this study analyzed that if it installs a median stirp, it has to ensure one meter, and such a thing could prevent the separation of lane or damage of facilities. However, if it is hard to ensure the space because of narrow road width, it could install a median strip in case of installing the road surface mark 0.5m. And the installation of the attention inducement stick or a median strip on the central line could be possible to induce the violation of central line, thus it is desirable not to install only anythings but also raised pavement markers.

• The Korean Society of Law and Medicine
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• v.17 no.2
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• pp.125-144
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• 2016

All forms of Clinical trial should be fully equipped with protection systems for experimental subjects considering their uncertainty and various risks. Existing laws have some regulations in pharmaceutical affairs act and medical device act. Nonetheless, there is a limit to protect the subjects considering law objective to perform administration of medicine. Furthermore, the clinical trial on minor has no direct regulations in pharmaceutical affairs act, but prescribes certain portion in clinical trial assessment guideline on infants or medicine clinical trial management standard, however there is a limit because that is just recommendation not having legal effectiveness. The legislative solution would be possible for legal problems of clinical trial on minor by examining treatment system on minor in organ transplant act and clinical trial on minor in other foreign laws stronger than usual medical practice in terms of degree of human body invasion. I suppose that the control system of clinical trial being done focusing on the pharmaceutical affairs act, medical device act and other guidelines in existing laws system should be resolved by legislating 'trial subject protection law', in addition, this would be well balanced in organ transplant act on protection system of minor organ donors. Furthermore, the judgement on the consent ability and spontaneity in clinical trial on minor should be judged considering maturity and mentality of minor by clinical trial institutional review board based on legislative solution mentioned above.

• Journal of Welding and Joining
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• v.15 no.6
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• pp.24-31
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• 1997

2매의 금속을 맞대어 그 한 쪽에 접촉면과 평행하게 고주파진동을 가하면 단 시간에 접합된다. 이공정을 초음파 용접이라고 하며 그 물리적인 본질은 아직 불분명 하지만, 첫째로는 강한 마찰에 의해 금속 자유면의 산화물층이 제거되기 때문이라는 점과 둘째로는 마찰에 의해 금속 표면이 강하게 가열되어 이에 따른 연화에 의해 접합 이 된다고 하는 점이다. 그러나 이와 같이 가열된다고 하더라도 가열은 표면부에만 국한되고 다른 부분은 가열되지 않는다. 따라서 초음파용접은 냉간접합이라고도 한다. 또 가압력과 진동에 의한 힘이 동시에 작용하기 때문에 용접할 면을 미리 청정하게 할 필요는 없고 용접전의 단계에서 자연적으로 청정화가 이루어진다고 하는 사실이 간접 적으로 증명되고 있다. 초음파 용접(Ultrasonic welding)의 특징을 요약하면 고상용접 의 일종으로서 용접중에 국부적으로 고주파 진동에너지와 압력을 가하여 용접하는 방법이다. 이 때 모재를 용융시키지 않고 건전한 야금학적 결합부가 얻어진다는 데에 큰 특징이 있다. 또한 초음파용접은 다른 용접법에 비해 경제성이 매우 높고, 초음파 용접에 필요한 출력이 전기아크 용접에 필요한 출력의 5 - 10%로 충분한 경우가 많다. 초음파 용접은 통상의 방법으로는 용접하기 어려운 동종 금속이나 이종 금속의 용접에 널리 사용된다. 이 용접법은 반도체, 미세회로, 전기 접점의 형성에 대한 생산기술 로서 사용되고 있는데 소형 모터, 알루미늄 박의 가공, 알루미늄 합금의 조립 등에 이용되고 있다. 한편 최근에는 자동차, 우주항공산업 분야의 구조제 용접용으로도 채용되고 있다.출함이 바람직하다.분비되는 배설-분비 항원의 자극과 깊은 관계가 있음을 알 수 있었다.넌트 명세서를 대한 XML DTD(Document Type Definition)를 정의하고, HTML 기반 검색 방법과 XML 기반 검색 방법에 대한 컴포넌트 검색 성능을 비교한다.따라 NO 생산 및 세포독성이 증가하였고. NO 생산을 저하시키는 약제들은 활성화된 복강 대식세포 및 RAW264.7 세포에 의한 질편모충에 대한 세포독성을 현저히 감소시키는 것으로 보아 NO는 질편모충에 대한 대식세포의 숙주 방어기전에서 중요한 역할을 감당할 것으로 생각된다.nction index) 와 최대개구시 동통의 정도는 시술전과 시술 4주후간에 유의한 차이가 관찰되었다.피부온도는 검사자간에는 특정부위에 따라 다소 차이가 있을 수 있으나 일반적으로 높은 재현성을 보여줌으로서 향후 교근 및 측두근의 임상연구 평가에 피부온도조사는 도움이 되리라 사료된다. lactobacilli의 양은 peroxidase system을 함유하거나(p < 0.01) 함유하지 않은(p < 0.05) 치약을 사용한 군 모두에서 양치전에 비해 유의성있게 감소하였다. 6. 양치후 30분에 채취한 구강건조증 환자의 자극성 전타액내 S. mutans 양은 peroxida system을 함유한 세치제를 사용한 군에서 대조군에 비해 유의성있게 낮았다(p < 0.05). 7. 양치후 30분에 채취한 구강건조증 환자의 자극성 전타액내 lactobacilli양은 peroxidase system을 함유한 세치제를 사용한 군에서 대조군에 비해 상대적으로 낮게 나타났으나(p = 0.067)

• Archives of design research
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• v.16 no.1
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• pp.25-34
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• 2003

At the global times, each country is developing various designs, symbolizing its m country's original images. So significant and continual developments must be made in the aspect of the national identity and image promotion as well as for producing added value by commercializing the designs in the manner of discriminating against other cultures. What is the image which represents Korea\ulcorner Though there are many images, such as the national flag of Korea, a rose of Sharon, the Korean national anthem, Kimchi, Korean clothes, in this research I select "Taeguek" patterns in order not only to be able to associate the Korean national flag but to have a strong odor tone and aesthetic factors. The "Taeguek" patterns, Which stands for harmony and prosperity, have been used in the Korean buildings and in the small tolls for practical lives of Korean people from the old times. Recently we are asked to develop a variety of cultural assets for lots of international event held these days. So this research is trying to apply the patterns of "Taeguek" to our reality, the division of the Korean peninsular. In the doctrine of the five natural elements, although Um and Yang are incompatible, they can be combined and then lead to a mutual harmony by accomplishing a good balance. Just in the same way, the South and North, which seem incompatible by appearance, can live together and eventually be united. By implanting that meaning into the patterns of "Taeguek", the postcards can make the meaning of unification visually dear and can assist to speed up the unification of south and North and to show our hope to the world.North and to show our hope to the world.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.178-186
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• 2011

This study was conducted to investigate runoff characteristics of non-point pollutant sources in an agricultural area watershed in Boeun area, Chungbuk Province. The monitoring site represented 1.56 $km^2$, about 44.4% of which was covered with paddy fields. The monitoring was conducted for six events in a period of 5 month. Event Mean Concentration (EMC) and Site Mean Concentration (SMC) of suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (T-N) and total phosphorus (T-P) were calculated using the results of the water quality parameters. A comparison between arithmetic mean concentration and EMC revealed that nearly all EMCs were higher than the corresponding arithmetic mean concentrations. First-flushing effects were exhibited for SS, BOD, and T-P, with relatively high concentrations in early-stage storm events.

• The Journal of Pediatrics of Korean Medicine
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• v.15 no.1
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• pp.261-265
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• 2001

소아의 소화성궤양은 소아 소화계질환 중에서 발병율이 점차 늘어나고 있는 추세에 있다. 최근 소아과에서 내시경의 활용이 활발해지면서 장기적으로 반복하여 위완통(胃脘痛), 변혈 (便血)및 구혈(嘔血)이 나타나는 경우 궤양성질환의 가능성이 높은 것으로 밝혀지고 있다. 본원에서는 유명한 중의사 왕붕비(王鵬飛) 교수의 비완통(脾脘痛) 치험방을 토대로 많은 임상을 거쳐 위평충제(胃平沖劑)를 개발하여 1992년6월부터 1997년12월까지 위내시경 검사를 통하여 위궤양으로 진단된 98명의 소아환자에게 투여하여 관찰한 바 만족스러운 효과가 나타나 이를 보고한다. 위평충제(胃平衝劑)의 처방구성은 자초(紫草), 청대(靑黛), 곽향(藿香), 유향(乳香), 회향(茴香), 정향(丁香), 황련(黃連), 적석지(赤石脂), 황정(黃精) 등이다. 한의학적 이론에 따르면 불규칙하고 자극성이 강한 음식섭취 습관은 비위(脾胃)를 손상시켜 중주(中州)를 옹체(壅滯)시키므로 기(氣)의 원활한 소통이 이루어지지 않으면 부통즉통(不通卽痛)의 기전으로 발전한다. 또한 근래 소아들이 각종 정신적인 압박으로 스트레스가 쌓이면서 간기울결(肝氣鬱結)을 초래하여 울화(鬱火)로 인하여 혈락(血絡)이 손상되면서 출혈증상이 나타난다. 왕교수의 견해에 따르면 체내에 어혈이 제거되지 않으면 기혈(氣血)의 순환이 더욱 악화되어 어적(瘀積)이나 궤양 또는 경새(梗塞) 등을 일으키게 된다고 하였다. 따라서 위평충제(胃平沖劑)는 활혈화어(活血化瘀), 청열해독(淸熱解毒)과 더불어 익기양위(益氣養胃), 거어지통(祛瘀止痛)의 효능이 있는 약물들로 구성되었다. 동물실험에서 위평충제(胃平衝劑)는 궤양표면을 보호하고 치유하며 재발을 방지하는 효과가 있는 것으로 확인되었고, 위액의 분비, 위단백질효소의 활성에 대한 억제 및 진통효과도 있는 것으로 입증되었다.행하여 사용하는 것이 바람직하며, 단순한 중약 투여는 일부 양약에 의한 소아성장에 미치는 영향을 피할 수 있어 더 많은 임상연구가 이어져야 한다.(當歸) 목단피(牧丹皮) 울김(鬱金) 정력자(?歷子) 세신(細辛) 오미자(五味子) 구기자(枸杞子) 산수황육(山茱黃肉) 황기(黃?) 감초(甘草) 등을 기본적으로 사용한다. 비신양허형(脾腎陽虛型)은 온보비신(溫補脾腎) 화어척담(化瘀滌痰)을 원칙으로 하며, 처방에는 구마황( 灸麻黃) 세신(細辛) 오미자(五味子) 당귀(當歸) 단삼(丹蔘) 울김(鬱金) 정력자(?歷子) 반하(半夏) 보골지(補骨脂) 선령비(仙靈脾) 태자삼(太子蔘) 황기(黃?) 감초(甘草) 등을 기본적으로 사용한다. 치험(治驗): (1) 천식의 실증(實證)은 치료를 한 뒤 완화단계에 접어들면서 허증(虛證)으로 전화되는데, 허천(虛喘)도 역시 천식이니 만큼 단순히 보법(補法)만 사용하여서는 안된다. 시종일관 천식치료에는 척담화어(滌痰化瘀)의 원칙을 지켜야 한다. 폐내(肺內)의 담어(痰瘀)가 철저하게 제거되어야 폐(肺)의 순환기능을 개선시켜 기도(氣道)의 염증을 신속히 흡수하고 치유할 수 있다. 이와 같은 치료과정은 약 3-6개월이 필요하다. 완화단계의 기간이 길어질수록 완치될 확률도 높아진다. (2) 급성기 천식은 폐(肺)를 다스려야 한다. 폐(肺)를 다스리는 방법에는 선폐(宣肺), 청폐(淸肺), 온폐(溫肺), 윤폐(潤肺) 및 척담거어(滌痰祛瘀) 등이 있다. (3) 증상이 완화되면 신(腎)을 다스린다. 천식은 신허(腎虛)가 근본적인 원인이므로 완화단계에서 심지어 발작기에도 보신제(補腎劑)를 추가하여 사용하면 배의 효과를 얻을 수 있다. (4) 비(脾)의 기능을 강화하여 근본을 채우는 부비배본(扶脾培本)도 중요하다. 후천의 수곡정미(水穀精微)로 선천을 충족시키고 자양하는 것은 질병에 대한 저항력을

• Korean Journal of Environment and Ecology
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• v.23 no.1
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• pp.50-55
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• 2009

To understand the status of the migrating Oriental Honey Buzzard(Pernis ptilorhynchus) in Korea, we carried out a preliminary study on the number and local movements of the Honey Buzzard from September 2005 to October 2007 at Hongdo Island, Jeonnam Province, Korea. A total of 702 Honey Buzzards in 2005, 404 individuals in 2006, and 659 individuals in 2007 were recorded during the fall migration season, but during the spring migration season only two and eight birds were observed in 2006 and 2007 respectively. The migrating Honey Buzzard showed peak numbers from 20 September to 5 October at the study site. According to observation of arrival time of538 Honey Buzzard in October 2007, a total of 2l6 birds(40.l %) were passing over Hongdo Island between 7:00 AM to 8:00 AM, rising skyward on columns of warm air. This suggests the use of thermal currents and avoidance of nocturnal movement for crossing water. They preferred moderate winds(<5 m/s in speed) from northwest, but the migrating number apparently decreased in case of strong winds (${\geqq}5 m/s$). This suggests that wind speed and direction are important environmental factors for migration of the Oriental Honey Buzzard. At present, it is unclear which breeding population(from north-eastern China or Japan) passes over Hongdo Island. Moreover, it is difficult to prove migration route and to understand migratory behaviors of the Oriental Honey Buzzard in Korea. To prove the breeding sites and routes of the migrants over the study site, we need more detailed and further studies such as satellite tracking researches.

• Korea journal of population studies
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• v.29 no.1
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• pp.269-292
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• 2006

The current environmental problem is global, and threatens the very existence of human beings. Many factors have been argued as the causes of environmental problem. The examples include anthroponcentric human perspective on nature, increase in the knowledge on nature, development of technology, economic growth and unequal distribution, and population increase, etc. The scholars who argues population increase have focused on over-population. However, the estimation of optimum population size has not been attempted in terms of environmental carrying capacity. In such a context, this paper aims at estimating optimum population size in South Korea in terms of environmental carrying capacity. The estimation was done from two approaches. One was based on the state of environment, the other was based on 'the desirable state of environment' Koreans expect. The former is termed an objective approach, while the latter is termed an approach based on social consensus. About 47.5 millions were estimated from the former approach, and 48.5 millions from the latter approach. However, optimum population size increase by 50.5 millions if government increase environmental budget to 2.00% among total budget. As such, different optimum population size is estimated according to the values of variables. The most significant variable determining optimum population size is environmental budget, and followed by supply of clean energy. The estimated optimum population size was based on the time-series data from 1993 to 2002. Therefore, time-series data collected from other years will result in different estimation model, and then different optimum population size will be estimated.