• Journal of Environmental Policy
• /
• v.8 no.3
• /
• pp.115-138
• /
• 2009

The purpose of this paper is to clarify the main components of economic growth and the effects of environmental factorson productivity by comparing traditional productivity growth and environmentally-adjusted productivity growth in 28 Chinese regions based on growth accounting analysis. To do this, we measured the shadow prices of SOx for the 28 Chinese regions. This study found that the annualized growth rate of output in the 28 Chinese regions was almost 10.07% for 1999-2005, though the growth rate was higher in the eastern region than in the middle and western regions. The average traditional productivity was 3.58%, again with the eastern region showing the highest level. The average environmentally-adjusted productivity of the three regions was about 3.56%, which is similar to the level of traditional productivity. This implies that activities regarding pollution reductions in the 28 Chinese regions have not been practiced, even though environmental regulations have been strengthened. Therefore, the regional and central governments should strengthen environmental regulations and strictly enforce them.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.30 no.4
• /
• pp.667-672
• /
• 2003

Rieger syndrome is a rare, autosomal dominant genetic disorder characterized by malformation of the anterior chamber of the eye(goniodysgenesis) coincident with hypodontia. It may also be accompanied by a spectrum of dental, craniofacial and somatic anomalies. Mutations in paired-like homeodomain transcription factor2(PITX2) are associated with the syndrome, and its frequency in the general population has been estimated to be 1 : 200,000. In the present case, the patient, 4 year 7 month-old female, had posterior embryotoxon and polycoria. The maxilla was retrusive in cephalometric radiography. She had congenital missing on #52, #62 and some tooth germs of permanent tooth were not detected in panoramic radiography. The purpose of this paper is to report the dental and craniofacial findings and review the pertinent literature through this case.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.41 no.3
• /
• pp.39-44
• /
• 2004

Fiber Bragg grating sensors are fabricated by core index modulation using UV laser and phasemask. Bragg wavelength of the grating is changed by the external strain. In this paper, a signal processing system of fiber Bragg grating sensor has studied in the optical wavelength domain. The system is based on the sweep semiconductor light source that consists of SLD, F-P tunable filter and etalon filter. The hysteresis effects of PZT in the F-P tunable filter are compensated. The long term measurement stability is obtained by controlling the temperature of F-P tunable filter and the SLD. We compare the strain data from fiber Bragg grating sensor and that from strain gauge at concrete hume pipe. We also get very good results for the long gauge displacement using fiber Bragg grating sensor which are identical to the data with short gauge length ordinary displacement sensor.

• Geotechnical Engineering
• /
• v.11 no.4
• /
• pp.125-140
• /
• 1995

Generally, the groundwater pressure is not considered in the design of concrete lining of bottom drainage tunnel. This design method implies that the phreatic surface is drawdown to the bottom of tullnel. When tile groundwater is continually supplied without changing of groundwater table, there is a possibility at which the groundwater pressure acting on the tunnel lining after the completion of tunnel. Therefore, the safety of tunnel lining must be checked in this case. In this paper, the stability of bottom drainage tunnel which is affected by groundwater discharge is analzed by using of the Finite Element Method at the 2 sections of subway where the groundwater level has a tittle change during the construction. As the result of analysis, the grouting for the water tightness and the permanent monitoring system of tunnel are required for maintaining of long-term stability of bottom drainage tunnel for the case of groundwater plassure acting on the tunnel lining is greater than that of design stage.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2012.05a
• /
• pp.930-930
• /
• 2012

최근 기후변화로 인하여 전 세계적으로 물 부족현상이 대두되고 있는 가운데 우리나라 또한 물 부족국가에 편재되어 있다. 더군다나 제주도는 최대 다우지임에도 불구하고 다른 타 지역과 마찬가지로 제주도 곳곳에서 물 부족 현상이 야기되고 있다. 이러한 현상은 제주도의 강우가 대부분 년 중 6월~9월에 집중되고, 그 기간 홍수유출 역시 경사가 급하고 15km 미만의 짧은 유로연장을 갖는 대부분의 하천의 특성상 홍수유출 지속시간이 단 시간에 불과하여 수자원 관리에 큰 어려움이 있기 때문으로 사료된다. 다만 일부하천의 경우 해안과 가까운 지점의 하상과 측벽에서 기저유출 성분인 용천수가 유출됨으로 1970년대부터 상수원으로 개발하여 일부분 이용되고 있다. 하지만 이 또한 정확한 용출량 산정이 어려워 수자원으로써의 활용이 미흡한 실정이다. 따라서 본 연구에서는 대상유역의 기저유출로 발생되는 용천수의 용출량을 산정하여 용천수의 이용 및 보전관리계획을 수립하는 중요한 척도를 제시함은 물론 제주 수자원의 대부분을 차지하는 지하수의 함양, 배출, 순환연구에 중요한 기초자료로 활용하기 위하여 진행되었다. 본 연구는 제주도 중서귀수역 주요 기저유출유역(강정천, 악근천)에 대하여 연구대상기간(2011.7~2011.12) 동안 하천의 유출량을 ADCP(Accoustic Doppler Current Profiler, SonTek사)와 전자기식 유속계(FLOW-MATE)를 이용하여 매월 2회 현장 계측을 실시하여 유출량 자료를 확보하였고, 일 단위의 모의가 가능한 유역단위의 준 분포형 장기 강우-유출 모델(continuous rainfall-runoff model)인 SWAT(Soil Water & Assessment Tool) 모델을 적용한 물수지 결과값과 비교 검정하여 제주도 기저유출 하천의 유출율 및 수문곡선의 특성을 분석하고 SWAT 모델을 통한 물수지 산정을 실시하였다. 중서귀수역의 기저유출 대상유역에 대한 지속적인 관측자료와 세계적인 SWAT모델을 이용한 정밀 수자원 해석결과는 서귀포시의 주 식수원으로 이용되고 있는 대상유역의 물순환 및 물수지분석과 통합 수자원의 연구진행, 향후 기후변화에 대비한 효율적인 수자원의 이용 및 확보를 위한 귀중한 자료로 이용될 수 있을 것으로 사료된다.

• Journal of The Geomorphological Association of Korea
• /
• v.19 no.2
• /
• pp.161-172
• /
• 2012

The Taeanhaean National Park is located on the middle of the west coast of Korean peninsula. Due to the relatively high wave energy, large tidal range which is about 7m, and extremely complex coastal line, various coastal land-forms such as mud-flats, sand beaches, sand dunes, sea cliffs etc. are well distributed in this area, and thus various coastal ecosystems are well preserved. However, because of reckless sand diggings and construction of artificial structures in the coastal zone, the natural flowing and exchange of coastal deposits were disturbed and the erosion in the beach and the dune has been seriously accelerated. To understand of the causes of these problems, we tried three times periodical measuring with VRS/RTK GPS instrument at the Hakampo and Anmyeon beach. According to seasonal changes of the coast-line, beach area and cross-section of study sites, generally erosion process was dominated in the summer and deposition process was followed after summer.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.1
• /
• pp.122-129
• /
• 2019

Due to its nature the manufacturing industry faces a cyclical economy, and therefore there is an urgent need for a companion industry to cope with this cyclic pattern in the long run. The sector suitable for meeting this demand is the repair and shipbuilding industry. In order to operate a shipbuilding repair business, a floating dock is indispensable, and most obsolete floating docks were imported from overseas and operated through repair/maintenance. However, there is no precise guideline for floating dock safety, and most models have been in use for at least 30 years without being required to enter classification at the time of operation. In this study, structural strength analysis was carried out using measured thickness information of aged floating docks, and the residual structural strength of floating docks in operation was analyzed. The main results derived from this study can be referred to as guidelines for the review of the structural safety of similar equipment, and it is expected that an optimal solution will be found within a short time using this method for repair/maintenance.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.4
• /
• pp.407-413
• /
• 2022

In this study, the empirical formula for evaluating cable tension based on long-term measurement for about 3 years according to temperature change was proposed by proving the correlation between the expansion joint displacement of the upper road bridge and the cable tension of the lower railway bridge. The tension prediction results using the empirical formula for tension evaluation each cables proposed in this study were found to be in good agreement with the cable tension using the vibration method within 3%. Therefore, it was analyzed that it could be applied together with the vibration method that was an experimental technique, to predict and evaluate the cable tension in serviced railway steel composite bridge. As a result of applying the estimated temperature calculated by the empirical formula for expansion proposed in this study to the empirical formula, it was analyzed that a high level of reliability could be secured when compared with the vibration method. Therefore, it is judged that the empirical formula for cable tension evaluation reflecting the estimated temperature proposed in this study can be used to predict the tension of cables according to climate change in the future and establish a maintenance plan.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.43 no.3
• /
• pp.297-308
• /
• 2023

Displacement of structures is the most important parameter for safety and performance assessment and is measured to use for diagnosis and maintenance of bridges. Usually LVDT, Laser and GNSS are used for displacement measurement but these measurement instruments have problems in terms of field condition and cost. Therefore, in this study, displacements were evaluated using rotational angle measured by inclinometers and the proposed algorithm was experimentally verified. As the result, vertical displacements of cable supported bridges with traffic and temperature load were properly evaluated through the proposed algorithm. Therefore it is considered that the proposed algorithm can be used for displacement measurement by vehicle load test and long term displacement monitoring.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2021.06a
• /
• pp.293-293
• /
• 2021

자연유량이란 인위적 행위에 의한 하천의 유량 변화가 없는 개발되지 않은 상태의 하천유량을 말하며, 실제 유량을 측정하거나 관측자료를 활용한 장기유출모형을 통해 산정할 수 있다. 미계측 유역에 대한 강우-유출 모형 구축시, 무엇보다 실제 미계측유역에 적용시 나타날 수 있는 문제점을 최소화할 수 있는 방향으로 모형 개발이 이루어지는 것이 필요하다. 강우-유출 모형 매개변수의 수가 많아질수록 과적합(over-fitting)의 발생 소지가 증가하게 되며, 지역화 모형 구축시 불확실성을 더욱 가중시키게 된다. 이러한 이유로, 모형의 검정보다는 검증에 초점이 맞춰져 있어야 하며, 더불어 사용되는 강우-유출 모형의 매개변수가 적어야 한다. 본 연구에서는 대표 강우-유출모형의 선정시 여러 평가 기준 중 예측의 정확성 측면에서 통계적 지표를 통해 모형의 수행능력에 중점을 두었으며, 적은 개수의 매개변수를 갖음에도 불구하고 상대적 우수한 모의결과를 제공하는 GR4J(Ge'nie Rural a 4 parame tres Journalier)모형을 최적 유출모형으로 선정하여 댐 상류유역에 대한 자연유량 재현성능을 평가하였다. 최종적으로 강우-유출모형의 최적매개변수와 유역특성인자 사이의 상호연관성을 고려해 매개변수를 지역화하기 위하여, 본 연구에서는 두 가지 이상의 변량에 대한 상관성을 효과적으로 재현하는데 효과적이며, 자유로운 주변확률분포 선택과 결합확률분포의 추정이 용이한 장점이 있는 Copula 함수를 활용하였다. 제시된 방법론에 대한 적합성을 평가하기 위해 교차검증 관점에서 지역화된 매개변수의 적합성을 검토하였으며, 본 연구에서 도출된 결과는 유역특성에 따른 미계측유역의 자연유량 산정시 지역 매개변수를 강우-유출모형에 활용함으로써 신뢰성 있는 자연유량 산정 결과를 제공할 수 있을 것으로 판단된다.