• 한국환경과학회지
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• 제12권9호
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• pp.967-976
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• 2003

Volatile organic compounds (VOCs) are present in essentially all natural and synthetic materials from petrol to flowers. In this study, indoor and outdoor VOCs concentrations of houses, offices and internet-cafes were measured and compared simultaneously with personal exposures of each 50 participants in Asan and Seoul, respectively. Also, factors that influence personal VOCs exposure were statistically analyzed using questionnaires in relation to house characteristics, time activities, and health effects. All VOCs concentrations were measured by OVM passive samplers (3M) and analyzed with GC/MS. Target pollutants among VOCs were Toluene, o-Xylene, m/p-Xylene, Ethylbenzene, MIBK, n-Octane, Styrene, Trichloroethylene, and 1,2-Dichlorobenzene. Indoor and outdoor VOCs concentrations measured in Seoul were significantly higher than those in Asan except Ethylbenzene. Residential indoor/outdoor (I/O) ratios for all target compounds ranged from 0.94 to 1.51 and I/O ratios of Asan were a little higher than those of Seoul. Relationship between personal VOCs exposure, and indoor and outdoor VOCs concentrations suggested that time-activity pattern could affect the high exposure to air pollutant. Factors that influence indoor VOCs level and personal exposure with regard to house characteristics in houses were building age, inside smoking and house type. In addition insecticide and cosmetics interestingly affected the VOCs personal exposure. Higher exposure to VOCs might be caused to be exciting increase and memory reduction, considering the relationship between measured VOCs concentrations and questionnaire (p<0.05).

• 한국환경보건학회지
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• 제27권1호
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• pp.20-26
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• 2001

personal nitrogen dioxide(NO$_2$) exposures for 31 professional drivers were measured using passive sampler and time activity diary in Asan and Chunan area, and were estimated using time-weighted average model. Mean concentrations of driver’s indoor and outdoor were 24.7$\pm$10.7 ppb and 23.3$\pm$8.3 ppb, respectively with indoor/outdoor of 1.1. Mean personal NO$_2$ exposure was 30.3$\pm$9.7 ppb. Personal NO$_2$ exposures were strongly correlated with indoor car NO$_2$ levels ($R^2$=0.80) rather than residential indoor NO$_2$ level ($R^2$=0.55). and outdoor NO$_2$ level ($R^2$=0.50). The driver’s NO$_2$ exposure using LP-gas with 24.4$\pm$8.0 ppb were statistically different from those using diesel with 36.3$\pm$14.1 ppb(p<0.01). The effect of driver’s smoking for personal NO$_2$ exposure was not found. It was considered that the main NO$_2$in driver is transportation. Since drivers mostly spent their times in indoor and inside car, time-weighted average model could be used to estimated personal NO$_2$ exposure using time activity diary, Though we did not measure all microenvironments, the estimated personal NO$_2$ exposures with 26.9$\pm$10.2 ppb were statistically correlated with measured personal NO $_2$ exposures30.3$\pm$9.7 ppb ($R^2$=0.89). The mean and standard deviation of personal NO$_2$ exposure using Mote-Carlo simulation were 26.6$\pm$7.2 ppb.

• 대한지리학회지
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• 제40권3호
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• pp.310-320
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• 2005

이 연구는 GPS 수신기를 통해 수집된 개인통행자료를 이용하여 통행패턴의 시공간적 특성을 다양한 그래픽으로 요약하고 탐색적 분석을 가능케하는 지리적 시각화 환경을 제안하고 이를 구현 및 평가하는 것을 목적으로 한다 이 연구에서는 시공간입방체(space-time cube)를 바탕으로 시간지리학 개념을 시각적으로 표현하였으며, 시간산포기둥(temporal dispersion cylinder), 평행평면그림(parallel plane plot)과 같은 부가적인 시각화 도구의 구현을 통해 개인통행패턴의 시공간적 속성 및 이동경로 주위지역의 사회경제적$\cdot$자연적 속성을 함께 탐색할 수 있도록 하였다. 또한 사용자와의 상호작용을 통해 개인통행자료에 포함되어 있는 "언제", "어디에서", "무엇을"이라는 세 가지 정보요소들을 동적으로 탐색 및 질의할 수 있는 환경을 제공한다.

• 동아시아경상학회지
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• 제8권4호
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• pp.67-77
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• 2020

Purpose - This work tries to analyze the transformation of sectoral innovation pattern as time goes by to enhance the understanding on sectoral innovative activities, particularly considering the change of the nature of knowledge, and the trend of convergence. Research design, data, and methodology - This work tries to identify main factors, which determine the output of technological innovation through the econometric analysis, utilizing the result of Korean Innovation Survey and find a stylized fact on the change of the innovation pattern. Result - As a result of estimation, some major elements show different effects for two discrete years, 2002 and 2010; in chemical industry the open information source and neutral basic research become more important with the appropriation mechanism such as patents, and in machinery industry, the importance of internal information has been getting decreased with rising importance of customers. Conclusion - This work presents that some elements show different effects for two discrete years. Among three major elements, the source of information and appropriation mechanism shows different features for both industries. This means that we should explicit consider the changing nature of innovative environment, which leads to and heavily influence whether the innovative activity would be effective or not when we design innovation strategy and innovation policy.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권2호
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• pp.118-126
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• 2004

Recombinant E.coli ACV 1003 (recA::lacZ) releasing ${\beta}$-galactosidase by a SOS regulon system, when exposed to DNA-damaging compounds, have been used to effectively monitor endocrine disruptors. Low enzyme activity of less than 10 units/mL, corresponding to a $\mu\textrm{g}$/L(ppb) range of an endocrine disruptor (tributyl tin, bisphenol A. etc.), can be rapidly determined, not by a conventional time-consuming and tedious enzyme assay, but by an alternative interferometric biosensor. Heavily boron-doped porous silicon for application as an interferometer, was fabricated by etching to form a Fabry-Perot fringe pattern, which caused a change in the refractive index of the medium including ${\beta}$-galactosidase. In order to enhance the immobilization of the porous silicon surface, a calyx crown derivative (ProLinker A) was applied, instead of a conventional biomolecular affinity method using biotin. This resulted in a denser linked formation. The change in the effective optical thickness versus ${\beta}$-galactosidase activity, showed a linear increase up to a concentration of 150 unit ${\beta}$-galactosidase/mL, unlike the sigmoidal increase pattern observed with the biotin.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권5호
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• pp.1801-1816
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• 2014

Because HTTP-related ports are allowed through firewalls, they are an obvious point for launching cyber attacks. In particular, malware uses HTTP protocols to communicate with their master servers. We call this an HTTP-based command and control (C&C) server. Most previous studies concentrated on the behavioral pattern of C&Cs. However, these approaches need a well-defined white list to reduce the false positive rate because there are many benign applications, such as automatic update checks and web refreshes, that have a periodic access pattern. In this paper, we focus on finding new discriminative features of HTTP-based C&Cs by analyzing HTTP activity sets. First, a C&C shows a few connections at a time (low density). Second, the content of a request or a response is changed frequently among consecutive C&Cs (high content variability). Based on these two features, we propose a novel C&C analysis mechanism that detects the HTTP-based C&C. The HAS-Analyzer can classify the HTTP-based C&C with an accuracy of more than 96% and a false positive rate of 1.3% without using any white list.

• 천문학논총
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• 제14권2호
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• pp.91-102
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• 1999

We have made intensive calculations on the maximum relative sunspot number and the date of solar maximum of 23rd solar cycle, by using the statistical and precursor methods to predict solar activity cycle. According to our results of solar data processing by statistical method, solar maximum comes at between February and July of 2000 year and at that time, the smoothed sunspot number will reach to $114.3\~122.8$. while precursor method gives rather dispersed value of $118\~17$ maximum sunspot number. It is found that prediction by statistical method using smoothed relative sunspot number is more accurate than by any method to use any data of 10.7cm radio fluxes and geomagnetic aa, Ap indexes, from the full analysis of solar cycle pattern of these data. In fact, current ascending pattern of 23rd solar cycle supports positively our predicted values. Predicted results by precursor method for $Ap_{avg},\;aa_{31-36}$ indexes show similar values to those by statistical method. Therefore, these indexes can be used as new precursors for the prediction of 23rd or next solar cycle.

• 한국경제지리학회지
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• 제18권1호
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• pp.87-102
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• 2015

본 연구에서는 정보통신정책연구원에서 실시하고 있는 미디어패널조사에서 얻어진 미디어 이용자들의 미디어 다이어리 데이터에서 미디어 수용자들의 활동공간 이용 시공간 정보를 추출하고, 이를 활용하여 도시 실시간 인구분포를 산정하는 방법론을 제시하고자 한다. 이를 위하여 도시민의 시공간 정보가 상대적으로 다양하여 비교검토가 가능한 서울시를 연구대상 지역으로 선정하고, 서울시 미디어 이용자들이 도시민들의 주요 활동공간인 주거, 업무, 교육, 교통, 상거래 등 다양한 활동공간별로 하루 중 시간 흐름에 따라 머무는 비율의 변화를 분석한다. 활동공간에 따라 하루 중 시간 흐름에 따라 머무는 인구비율은 상당한 차이를 보인다. 이러한 미디어 이용자의 시공간 정보 활용의 타당성을 확보하기 위하여 서울시 대중교통이용자의 시공간적 이동 정보를 담고 있는 교통카드 데이터에서 얻어진 내용과 비교한다. 도시민의 활동공간을 주거, 업무, 상거래의 활동공간으로 범주화하여 활동공간 범주별 실시간 인구 분포률을 산정하고, 이에 서울시 각 동별 거주 인구수 및 관련 산업별 고용자 수를 결합하여 서울시 동별 실시간 인구수를 산정한다. 서울에서 낮과 밤의 인구 분포에 나타나는 공간적 특성을 파악하기 위하여 주거 공간에 머무는 인구수에 가장 큰 격차를 보이는 오전 3시와 오후 3시 두 시점의 각 활동공간 범주별 및 이들을 총합한 실시간 인구수를 GIS를 활용 하여 지도화 하였다. 도시민의 대부분이 거주지를 떠나 일상과 관련된 활동공간에 머무르고 있는 오후 3시의 서울 실시간 인구분포는 업무공간과 상업공간의 분포가 결정적인 역할을 한다는 것을 확인할 수 있다. 반면에 밤 시간대의 인구분포는 주거공간 인구 분포와 거의 유사한 양상을 나타나고 있다.

• Journal of Oral Medicine and Pain
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• 제25권2호
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• pp.191-203
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• 2000

This study was performed to investigate the relationship between vertical dimension during swallowing and speech pattern in patients with temporomandibular disorders. For this study, 33 patients with temporomandibular disorders(TMDs), namely, 17 patients with disc displacement with reduction and 16 patients with disc displacement without reduction, and 30 normal subjects without any signs and symptoms in the masticatory system were selected as the patient group and as the normal group, respectively. Biopak $system^{(R)}$(Bioresearch Inc., Milwaukee, USA) was used for recording of electromyographic(EMG) activity(${\mu}V$) of the anterior temporalis, the superficial masseter, the sternocleidomastoideus and the trapezius insertion muscle during swallowing, and of mandibular positional change with function time(sec.) during swallowing and speech. A sentence of 'Sue is missing her house' was used for observing of speech pattern. Comparison between the two groups and relationship of the mandibular positional change and the function time between during swallowing and during speech were analysed by SPSS windows program. The results of this study were as follows : 1. Mean EMG activity of the trapezius insertion during swallowing was higher in the patient group, and the value was $3.4{\mu}V$ in patients and $2.1{\mu}V$ in normal subjects. 2. Vertica1 dimension(VD) at mandibular rest position before swallowing was slightly higher in the patient group, but VD at swallowing-late stage and at rest position after swallowing were not different between the two groups. 3. Swallowing time were 2.1 sec. in the patient group, and 1.5 sec. in the normal group, and the difference was significant. 4. VD during speech were generally higher in the normal group. In this case, speaking position showing the most difference between the two groups was 'her' position. The distance from habitual intercuspal position to 'her' position was 4.9mm in the patient group, and 6.6mm in the normal group. Speaking time was also longer in the patient group. 5. There were no difference in all observed items between the two categories of the patient group according to reduction of disc displacement. 6. Relationship between the positional changes during swallowing and speech were different between the patient group and the normal group. And in the normal group, VD at rest position before swallowing was negatively correlated with speaking time.

• 대한한방내과학회지
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• 제32권2호
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• pp.259-277
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• 2011

Objectives : The purpose of this study was to investigate two subjects: the diagnostic value of bilateral lowering of electrical activity at point H4,5,6 of Ryodoraku and the mechanism for Ryodoraku phenomena. Methods : Electrical activities of Ryodoraku test and electrogastrography recorded simultaneously and monitored continuously from 16 cases of functional dyspeptic patients were collected and their variations were grouped by the topics of discussion which were peculiarity, stability, lagging, alterability, and anomaly. Ryodoraku recordings obtained from 6 patients with different gastrointestinal diseases and 1 normal healthy person were used as control. The results are discussed with Nakatani's suggestion, theory of sympathetic nerve and Meridian Principle, respectively. Finely, coincidence of stomach arrangement between anatomy and meridian system in Ryodoraku was also evaluated. Results : Time-course variation showed a regular relationship between the typical pattern of Ryodoraku at point H4,5,6 and gastric myoelectrical activity. However, an irregular relationship and atypical pattern of Ryodoraku occasionally appeared. A literature search suggested that electrical response at the Ryodoraku point H4,5,6 may be dependent on an afferent sympathetic spinal reflex transmitted from the stomach. However, there was no evidence for making clear whether bilateral lowering of electrical activity at this point was induced by hypofunction of local sympathetic nerve in the skin itself or of signals transmitted from the gastric sympathetic nerve or not. The coincidence of 19% could not provide a visceral arrangement of the stomach between anatomy and meridian systems. Conclusions : Bilateral lowering of electrical activity at Ryodoraku point H4,5,6 has value as a diagnostic index for gastric dysmotility of functional dyspepsia. This phenomenon is associated with spinal reflex transmitted from the afferent sympathetic nerve in the stomach but not that of meridian function.