• Atmosphere
• /
• v.26 no.4
• /
• pp.541-551
• /
• 2016

A real-time quality control algorithm for $PM_{10}$ concentration measured by Continuous Ambient Particulate Monitor (FH62C14, Thermo Fisher Scientific Inc.) has been developed. The quality control algorithm for $PM_{10}$ data consists of five main procedures. The first step is valid value check. The values should be within the acceptable range limit. Upper ($5,000{\mu}g\;m^{-3}$) and lower ($0{\mu}g\;m^{-3}$) values of instrument detectable limit have to be eliminated as being unrealistic. The second step is valid error check. Whenever unusual condition occurs, the instrument will save error code. Value having an error code is eliminated. The third step is persistence check. This step checks on a minimum required variability of data during a certain period. If the $PM_{10}$ data do not vary over the past 60 minutes by more than the specific limit ($0{\mu}g\;m^{-3}$) then the current 5-minute value fails the check. The fourth step is time continuity check, which is checked to eliminate gross outlier. The last step is spike check. The spikes in the time series are checked. The outlier detection is based on the double-difference time series, using the median. Flags indicating normal and abnormal are added to the raw data after quality control procedure. The quality control algorithm is applied to $PM_{10}$ data for Asian dust and non-Asian dust case at Seoul site and dataset for the period 2013~2014 at 26 sites in Korea.

• Journal of the Korean School Mathematics Society
• /
• v.8 no.2
• /
• pp.249-271
• /
• 2005

The study was aimed to show effects of the newly step branch's feedback models on the mathematics underachievers' mathematics achievement and attitude toward the mathematics, extent of self-check. The subject are 26 mathematics underachievers in the End grade of H middle school located in Taejeon. They were divided into an experimental group and a control group, and the attribution disposition. Experiment group was provided step branch's feedback and control group was provided general formative' feedback. The duration of the treatment was over a period of six weeks. The result of study, the step branch's feedback was effects for increasing he mathematics achievement and attitude toward the mathematics than the general formative' feedback(p<.05). In addition, the step branch's feedback group had better extent of self-check than the general formative' feedback.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 1998.08a
• /
• pp.57.2-57
• /
• 1998

• Geophysics and Geophysical Exploration
• /
• v.10 no.1
• /
• pp.60-68
• /
• 2007

Conventional analysis of spectral induced polarization (SIP) data consists of measuring impedances over a range of frequencies, followed by spectral analysis to estimate spectral parameters. For the quantitative and accurate estimation of subsurface SIP parameter distribution, however, a sophisticated and stable inversion technique is required. In this study, we have developed a two-step inversion approach to obtain the two-dimensional distribution of SIP parameters. In the first inversion step, all the SIP data measured over a range of frequencies are simultaneously inverted, adopting cross regularisation of model complex resistivities at each frequency. The cross regularisation makes it possible to enhance the noise characteristics of the inversion by imposing a strong assumption, that complex resistivities should show similar characteristics over a range of frequencies. In numerical experiments, we could verify that our inversion approach successfully reduced inversion artefacts. As a second step, we have also developed an inversion algorithm to obtain SIP parameters based on the Cole-Cole model, in which frequency-dependent complex resistivities from the first step are inverted to obtain a two-dimensional distribution of SIP parameters. In numerical tests, the SIP parameter images showed a fairly good match with the exact model, which suggests that SIP imaging can provide a very useful subsurface image to complement resistivity.

• The Journal of Fisheries Business Administration
• /
• v.44 no.3
• /
• pp.1-14
• /
• 2013

This study considers an approach for subregional fisheries organization in Northeast Asia. The fishery resources in the Northeast Asian waters surrounding Korea are among the most productive in the world because of their extremely high biological productivity and the natural features of the sea. However, the fishery resources of the region have long been subject to heavy fishing pressures, and many stocks are now believed to be seriously depleted or even in danger of extinction because of overfishing. To move to a run sustainable fishery in Northeast Asia waters area, cooperative fisheries management between Korea, China and Japan for common resource is probably necessary. Cooperative fisheries management is likely to be more effective in fishery resources management than individual fisheries management by countries. The effects of fisheries management by regional cooperation can be divided into resource management and economical performance. Cooperative fisheries management as RFO will bring satisfactory results. Currently these jurisdictional extensions and resulting disputes over maritime space and resources were thrust upon an already transitional and unstable political environment. However, They have to have a strategic approach for RFO establishment step by step. Cooperative fisheries management using the RFO can mitigate these disputes, and cooperative bilateral fisheries arrangements have been proliferating over the past 10 years and may provide the basis for possible trust-building multilateral agreements.

• IE interfaces
• /
• v.22 no.1
• /
• pp.95-103
• /
• 2009

During the past few years, design of experiments (DOE) has been gaining acceptance in the telecommunications research community as a mean for designing and analyzing experiments economically and efficiently. In addition, the need for introducing a systematic robust design methodology (i.e., one of the most popular DOE methodologies) to network simulations has been increasing. In this paper, we present an architecture of voice over IP (VoIP) application and the E-Model for calculating the perceived quality of service (QoS). Then, we apply the Taguchi robust design methodology to optimize the perceived QoS of VoIP application, and describe the detailed step-by-step procedures. We have used ns-2 simulator to collect experimental data in which the SN ratio, a robustness measure, is analyzed to determine an optimal design condition. The analysis shows that "initial delay time in playout buffer" is a major control factor for ensuring robust behaviors of the perceived QoS of VoIP. Finally, we verify the proposed optimal design condition using a confirmation experiment.

• Transactions of Materials Processing
• /
• v.13 no.3
• /
• pp.216-224
• /
• 2004

In this study, we have developed a new UV$({\lambda}=355nm)$ laser micromachining technology by direct ablation method without masks. This technology allows that 3D micro parts can be fabricated rapidly and efficiently with a low price. And it has a benefit of reducing fabricating process simply. Due to micro parts' fabrication, such technologies need the control of XYZ stages with high precision, the design of optical devices to maintain micron spot sizes of laser beam and the control technology of laser focus. The developed laser manufacturing process for laser micromachining is that, after extracting coordinates of shape data from CAD model data, a beam path considering manufacturing features of laser beam is created by using genetic algorithm. This generated manufacturing process is sent to stage controller. In order to improve the surface quality of micro parts, we have carried out experiments on iteration manufacturing and beam step-over by using a minimum focus size. Moreover, we have fabricated a micro-channel through the developed laser micromachining technology and verified it through the results.

• Wind and Structures
• /
• v.30 no.5
• /
• pp.485-497
• /
• 2020

A study, using potential water wave theory, is conducted on the oblique water wave motion over two fixed submerged rectangular blocks (breakwaters) placed over a finite step bottom. We have considered infinite and semi-infinite fluid domains. In both domains, the Fourier expansion method is employed to obtain the velocity potentials explicitly in terms of the infinite Fourier series. The unknown coefficients appearing in the velocity potentials are determined by the eigenfunction expansion matching method at the interfaces. The derived velocity potentials are used to compute the hydrodynamic horizontal and vertical forces acting on the submerged blocks for different values of block thickness, gap spacing between the two blocks, and submergence depth of the upper block from the mean free surface. In addition, the wave load on the vertical wall is computed in the case of the semi-infinite fluid domain for different values of blocks width and the incident wave angle. It is observed that the amplitudes of hydrodynamic forces are negligible for larger values of the wavenumber. Furthermore, the upper block experiences a higher hydrodynamic force than the lower block, regardless of the gap spacing, submergence depth, and block thickness.

• Applied Chemistry for Engineering
• /
• v.8 no.2
• /
• pp.191-196
• /
• 1997

The isothermal reduction on $Pt/MoO_3/SiO_2$ at $50^{\circ}C$ demonstrates that the rate of hydrogen spillover is increased as calciantion temperature increases. That is due to the overlayer formation over the surface of Pt crystallites, investigated by TEM and CO chemisorption. It is known that reaction mechanism of skeletal isomerization of 1-butene into iso-butene is composed of 2 step such as formation of carbonium ion and isomerization of methyl group. It is expected that the increase of i-butene yield after calcination at $250^{\circ}C$ is due to increased rate of hydrogen spillover coming from first, overlayer formation over Pt surface and second, chlorine lessoning from $PtCl_x$ precursor.

• Imaging Science in Dentistry
• /
• v.31 no.1
• /
• pp.17-22
• /
• 2001

Purpose: To compare the film density of Insight dental X-ray film (Eastman Kodak Co., Rochester, NY, USA) with that of Ektaspeed Plus film (Eastman Kodak) under manual and automatic processing conditions. Materials and Methods : Insight and Ektaspeed Plus films were exposed at three different exposure conditions with an aluminum step wedge on the films under the three different exposure times. The exposed films were processed by both manual and automatic ways. The Base plus fog density and the optical density made by exposing step wedge were calculated using a digital densitometer (model 07-443, Victoreen Inc, Cleveland, Ohio, USA). The optical densities of the Insight and Ektaspeed film versus thickness of alumimun wedge at the same exposure time were plotted on the graphs. Statistical analyses were applied for comparing the optical densities of the two films. Results: The film density of both Insight films and Ektaspeed Plus films under automatic processing condition was significantly higher over the manual processing. The film density of Insight films was significantly higher than that of Ektaspeed Plus films on both automatic and manual processing conditions. Conclusion: The radiation exposure time can be reduced when using Insight over Ektaspeed Plus film. To take the full advantage of reducing exposure time, Insight film should be processed automatically.