This study aims to evaluate a porous concrete using hwang-toh, blast furnace slag and blast furnace slag (BFS) cement instead of type I cement. The tests that were carried out to analysis the properties of porous hwang-toh BFS cement concrete included compressive strength, continuous void ratio, absorption rate, and pH value, repeated freezing and thawing test were conducted. Test results indicated that the performance in porous hwang-toh concrete are effective on the kaoline based binder materials. The pH value were shown in about 9.5 ~ 8.5. The compressive strength was increased and void ratio was decreased with increasing the kaoline based binder materials, respectively. The void ratio and compressive strength were in the range of about 21 ~ 30 %, 8 ~ 13 MPa, respectively. The increased in void ratio of more than 25 % is showed to reduce the resistance of repeated freezing and thawing. Also, the resistance of repeated freezing of thawing and the compressive strength of porous hwang-toh BFS cement concrete are independent with hwang-toh content and BFS cement amount. But, the void ratio was decreased with increasing the high volume hwang-toh contents (more than 15 %).

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Owing to the recent developments in computer technology and nationally accumulated hydrology, land use, soil characteristics, flow and water quality monitoring data, high-level modelling results are required. However, as most catchments have a mix of urban and rural areas, it is challenging to apply one effective model. This study applied a hydrological simulation programme to a storm water management model for the Jeonju catchment, which has complex land-use characteristics, to determine the hydrological cycle of the catchment, analyse the river water quality and examine the structure of discharge pollutants. The linked model includes an analysis of the sewer pipes, which are the main path of hydrology and pollution loads in urban areas, a low-impact development application, a water circulation improvement technique and an initial storm water treatment facility installation project. This linked model will be very useful for guiding future urban water quality policy.

The purpose of this study was to examine the dose distribution characteristics of abutted fields of X-rays and electron beams on the basis of the electron shielding block's manufacturing method and apply those characteristics clinically in order to provide the benefits of dosimetry. To achieve this, we created electron shielding blocks by using two different methods: the existing method, without considering the electron beam's spreading (straight block), and a modified method, which takes this phenomenon into consideration (divergence block). Further, we cross-validated the physical dose measurements and the Monte Carlo simulations in terms of the nominal energies of the X-rays and the electron beams, the field size, and the measurement depth. As a result, compared to the straight block, the divergence block was found to reduce the overdose regions (hot spot) that occur at the field border between the X-rays and the electron beams and to increase the underdose regions (cold spot) that occur near abutted fields. Therefore, the divergence block showed a uniform dose distribution characteristic, providing a dosimetric benefit. In particular, this dosimetric benefit was maximized at the effective treatment depth (80% depth; maximum: 8.36% for the abutted field, maximum: 7.64% for the dose fluctuation region). Therefore, clinical application of shielding blocks, which provide dosimetric benefits at abutted fields by considering the phenomenon of electron-beam spreading, should be seriously considered to increase the accuracy of the prescription dose.