• Journal of Communications and Networks
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• v.6 no.2
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• pp.173-181
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• 2004

This paper shows a technique for regulating the rate emitted by UWB mobile terminals. This technique is designed to adapt the emission rate to the effects of channel capacity variations. We assume that individual flows are shaped at edge routers by means of dual leaky buckets. The proposal is based on the evaluation of certain parameters, which reflect the channel status, sent to the application layer. This information is generated by the scheduler designed to guarantee appropriate channel sharing for the various traffic components. We describe some results which highlight how performance depends on the specific operating conditions, as well as on the traffic descriptors of the flows, their reciprocal difference, and performance requirements.

• Proceedings of the Korea Water Resources Association Conference
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• 2000.05a
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• pp.48-56
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• 2000

In this paper, properties of hydrologic cycle in three experimental catchments were compared and different types of a lumped parametric model were applied to understand the hydrologic cycle in the catchments. One of them is a forest catchment and another one includes the reclaimed upland fields and last one does terraces paddy fields. The comparison of hydrologic properties showed that the differences in land use have great influences on the soil properties of surface layer, which changes in hydrologic processes such as evapotranspiration and storm runoff et. al. By the runoff analysis models, good agreements between observed and calculated discharge from the catchments were obtained and it was found that the differences in values of optimized model parameters and water budget components reflect those in the hydrologic cycle among them.

• Journal of KIISE:Information Networking
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• v.27 no.2
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• pp.206-218
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• 2000

Retransmissions on the DLC layer are essential to ABR service providing the low CLR (cell loss ratio) over the unreliable wireless channel with high bit error rate. In the wireless ATM, the DLC layer below ATM layer performs the retransmission and reordering of the cells to recover the cell loss over the wireless channel and by doing so, the effect of the wireless channel characteristics with high bit error rate can be minimized on the ATM layer which is designed under the assumption of the low bit error rate. We propose, in this paper, the schemes to reflect the changes of the transmission rate over the wireless channel on the ABR rate control. Proposed scheme can control the source rate to the changes of the transmission rate over the wireless channel and reduce the required buffer size in the AP (access point). In the simulation, we assume that the DLC layer can inform the ATM layer of the wireless channel quality as good or bad. Our simulation results show that the proposed schemes require the smaller buffer size compared with the existing scheme, enhanced dynamic max rate control algorithm (EDMRCA). It is also shown that the scheme with the intelligent DLC which adjusts the rate to the wireless channel quality not only provides the low CLR with smaller buffer requirement but also improves the throughput by utilizing the wireless bandwidth more efficiently.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.7
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• pp.1325-1334
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• 2016

The video incident detection System is a probe for rapid detecting the walker, falling, stopped, backwards, smoke situation in tunnel. Recently, the importance is increases from the downtown double deck tunnel in great depth underground space[1], but the legal basis is weak and the vulnerable situation experimental data. So, In this paper, we introduce a long-term log data analysis information in the tunnenl video incident detection system installed and experimental results in order to verify the feasibility of apply to video incident detection system for the double deck tunnel. It is proposed a few things about derives the problem of existing video incident detection system, improvements and reflect attributes for double deck tunnel. The contents described in this paper will contribute to refine the prototype of video incident detection system will apply to future double deck multi-layer tunnels.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.1
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• pp.9-16
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• 2016

As the need of eco-friendly transportation systems for sustainable development increases, public transport accessibility has been considered as an important element of transportation system design. When analyzing the accessibility, shortest path algorithms can be utilized to reflect the actual movement and we can obtain high resolution accessibility for all other stations on the network with shortest distance and time. This study used the algorithm improved by reflecting the penalty of number of transfers and waiting time of overlapped routes to get the accessibility. KTX Seoul Station is a target place and this algorithm is applied to multi-layer subway bus network of Seoul to calculate the accessibility, therefore this study presented the accessibility of KTX Seoul station by stations.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1865-1877
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• 2013

Vertical variations of polycyclic aromatic hydrocarbon (PAH) concentrations in $PM_{10}$ were investigated in order to assess the factors controlling their behavior in the urban atmosphere of Bangkok City, Thailand. Air samples were collected every three hours for three days at three different levels at Bai-Yok Suit Hotel (site-1 and site-2) and Bai-Yok Sky Hotel (site-3) in February $18^{th}-21^{st}$, 2008. The B[a]P concentration showed a value 0.54 fold, lower than the United Kingdom Expert Panel on Air Quality Standard (UK-EPAQS; i.e. 250 pg $m^{-3}$) at the top level. In contrast, the B[a]P concentrations exhibited, at the ground and middle level, values 1.50 and 1.43 times higher than the UK-EPAQS standard respectively. PAHs displayed a diurnal variation with maximums at night time because of the traffic rush hour coupled with lower nocturnal mixing layer, and the decreased wind speed, which consequently stabilized nocturnal boundary layer and thus enhanced the PAH contents around midnight. By applying Nielsen's technique, the estimated traffic contributions at Site-3 were higher than those of Site-1: about 10% and 22% for Method 1 and Method 2 respectively. These results reflect the more complicated emission sources of PAHs at ground level in comparison with those of higher altitudes. The average values of incremental individual lifetime cancer risk (ILCR) for all sampling sites fell within the range of $10^{-7}-10^{-6}$, being close to the acceptable risk level ($10^{-6}$) but much lower than the priority risk level ($10^{-4}$).

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.393-399
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• 2020

In this study, the subsidence behavior caused by groundwater ex-flow in a limestone cavity encountered during tunnel excavation was quantified based on numerical analysis and the effect was analyzed. Based on the groundwater level and surface subsidence surveyed at the site, a numerical analysis technique was applied to analyze the characteristics of the subsidence behavior according to the tunnel passage of the geological vulnerabilities. The results of groundwater seepage-coupled analysis were analyzed to reflect the actual ground subsidence behavior. As a result of the study, it was analyzed that the ground subsidence due to the tunnel excavation in the limestone common section(the geological vulnerable zone) was analyzed that the dramatical decrease in groundwater level was the main cause. As a result of numerical analysis, it was analyzed that the long-term cumulative settlement of the asphalt surface after the groundwater ex-flow was 76~118mm due to the reduction of the volume of the soil layer due to the decrease in the groundwater level, and the settlement amount increased as the depth of the soil layer increased.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.12
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• pp.615-641
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• 1999

Trade and the environment emerged as a major and complex issue for trade negotiators in the final stages of the Uruguay Round negotiations. The agreements and other international measures employing trade measures and trade sanctions for achieving global environmental objectives are Vienna Convention on the Protection of the Ozone Layer(1985), the Montreal Protocol on Substances that deplete the Ozone Layer(1987), The Framework Convention on Climate Change(1992), the Convention on Biological Diversity(1992), the Basel Convention on the Control of Transboundary Movement of Hazardous Waste and their Disposal(1992), the Convention on International Trade in Endangered Species of Wild Faunna and Flora(1975), the Rio Declaration, the Agenda 21, etc. The texts of the World Trade Organization(WTO) incorporated certain provisions which were designed to reflect some of the environmental concerns are Trade-Related Aspects of Intellectual Properity Rights(TRIPs), Trade-Related Investment Measures (TRIMs), the General Agreement on Trade in Services(GATS), and Technical Barriers to Trade(TBT) There is the possibility of conflict between multilateral environmental agreements and WTO agreements granting waivers against trade measures and sanctions. This remains a possibility, especially between countries which are Member of WTO and which are not Members of the relevant multilateral environment agreements, and countries which are Members of both the WTO and the relevant MEAs. Measures taken under the trade-related provisions of MEAs could potentially give rise to conflicts under obligations arising in WTO texts. If the parties in dispute are WTO members while they are not members of MEAs, the WTO provisions can be granted a certain priority in terms of international norms and vice versa. When the parties concerned are both WTO members and MEAs, it will be rational to grant the WTO provisions a priority. However, such measures should neither constitute a means of arbitrary or unjustifiable discrimination between countries where similar conditions prevail, nor create a disguised restriction on trade. Also any trade measures taken should be necessary to prevent developments in trade from endangering the effectiveness of an MEA and they should be proportional and least trade restrictive.

• The Journal of the Acoustical Society of Korea
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• v.19 no.1
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• pp.4-10
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• 2000

The work presented in this paper is about a postprocessor, which improves the performance of automatic speech segmentation system by correcting the phoneme boundary errors. We propose a postprocessor that reduces the range of errors in the auto labeled results that are ready to be used directly as synthesis unit. Starting from a baseline automatic segmentation system, our proposed postprocessor trains the features of hand labeled results using multi-layer perceptron(MLP) algorithm. Then, the auto labeled result combined with MLP postprocessor determines the new phoneme boundary. The details are as following. First, we select the feature sets of speech, based on the acoustic phonetic knowledge. And then we have adopted the MLP as pattern classifier because of its excellent nonlinear discrimination capability. Moreover, it is easy for MLP to reflect fully the various types of acoustic features appearing at the phoneme boundaries within a short time. At the last procedure, an appropriate feature set analyzed about each phonetic event is applied to our proposed postprocessor to compensate the phoneme boundary error. For phonetically rich sentences data, we have achieved 19.9 % improvement for the frame accuracy, comparing with the performance of plain automatic labeling system. Also, we could reduce the absolute error rate about 28.6%.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.397.1-397.1
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• 2014

최근 방사선 진단 영역에 이용되고 있는 증감지는 입사된 방사선의 감도를 증가시키기 위해 형광체를 사용하고 있으며, 외부의 에너지를 흡수하여 빛으로 방출하는 역할을 한다. 이는 방사선 검출기, 디스플레이, 의료기기 등 다양한 분야에 활용되고 있다. 필름에 X선을 노출 할 경우 형광체의 사용 유무에 따라 방사선 흡수 효율에 영향을 미치며, 이는 발광 효율 및 감도에 주요한 인자로 작용한다. 현재 상용화되어 있는 형광체는 낮은 발광 효율로 인한 한계를 가지므로, 발광 효율 향상을 위하여 제작 구조에 대한 연구가 진행되고 있다. 이 중 반사막을 활용하는 연구가 활발히 진행되고 있다. 일반적으로 형광체의 제조를 위하여 보편적으로 이용하고 있는 스크린프린팅 방법에서 건조 공정을 수행 시 균일도가 감소하는 현상이 발생한다. 이러한 현상은 반사막의 증착을 불균일하게 만드는 원인으로 작용하고 빛의 산란을 초래하는 현상을 초래한다. 이에 본 연구에서는 증착 시 투명도 저하에 따라 반사율이 증가되는 반사막 성질을 가지며, 방수성 및 절연성과 같은 보호층 특성을 지닌 유기성 투명 박막 페를린에 대하여 연구하고자 한다. 본 연구에서는 화학적 증기 증착법(Chemical Vapor Deposition, CVD)을 이용하여 투명 필름의 상단에 페를린을 코팅한 시편과 코팅하지 않은 시편으로 구분하여 제작하였고, 상단에 스크핀프린팅 방법을 활용하여 형광체를 도포 하였다. 시편 제작 후 실험은 시편을 필름 상단에 위치시키고, 일반진단에너지 대역(Model-SF 80)의 X선을 조사하였다. 이 후 현상기(model-pro14)를 통해 현상된 필름에 나타난 광학적 농도(Optical Density, O.D)를 농도계(Fluke Biomedical Nuclear Associates Densitometer)로 측정하였는데, 불확실성을 줄이기 위하여 총 5회를 측정하여 그 중 2번째로 높은 값을 도출하였다. 측정 결과, 페를린을 코팅한 형광체에서는 1.71의 O.D 값이 측정되었고, 페를린을 코팅하지 않은 형광체에서는 1.43의 O.D 값이 측정되었다. 이를 이용하여 투명도를 산출한 결과 상대적으로 약 1.76% 차이가 나타났다. 이러한 결과는 페를린 활용 시 환자의 피폭 선량 저감화 및 해상력 개선을 도모할 수 있을 것으로 사료된다.