• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.970-975
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• 2006

In the high oil prices age, intensification of energy efficiency promotion in the building sector is required. Windows are dominating large percentage whole building loads, and are regarding as the primary target of energy efficiency. The purpose of this study is to draw up a technical counterplan for the intensification of windows energy efficiency and spread promotion by quantitative thermal performance with KS test method for a comparison between the general Pair glass windows and the Low-e pair glass windows.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.833-836
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• 1995

A capacitor discharge impulse magnetizer is used to produce a high current pulse of short duration in a magnetizing fixture for magnets of the various shapes. The problem of designing custom fixtures for magnetization has often been considered more of conventional experience than a scientific theory. Therefore, the design of magnetizingfixture has until recently been a "cut and try" process. It was common to literally blow up one or more fixtures beforeachieving the desired results. Finite element CAD package allow the design of such a fixture. Since magnetizing fixtures come in a variety of sizes and shapes, there is usually no simple analysis method that can be used to estimate the field characteristics of the fixtures. Instead, one typically uses finite element analysis. FEA program MAXWELL is the primary tool used here. The purpose of this study was a examine both theoretically and experimentally the field characteristics inside the fixture. Independent of sizes and shapes of magnetizing fixtures, the desired magnetic field can be obtained with resonable predictability. The experimental results have been achieved using a 1000[V], 22.4[KJ] capacitor discharge magnetizer and iron-core fixtures.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.390-391
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• 2003

Cyclone is one of the most widely used gas - solid separation devices in industries. In spite of its many advantages, lower separation efficiency and flat separation curve are usually associated with cyclones. Therefore, the primary goal of cyclone research is to improve its separation capability while retaining its basic features. In this study, granules were filled in the cone of a cyclone in an attempt to increase the cyclone separation efficiency through the combination of granular filtration and centrifugal separation. (omitted)

• Journal of the Korean Society for Precision Engineering
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• v.11 no.6
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• pp.127-135
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• 1994

This paper is concerned about a high speed electromagnet of Pressure control solenoid valve. Solenoid valve is controlled by means of Pulse width modulation. The magnetostatic field problem on a solenoid is numerically solved by the 2-D axisymmetric finite element method. And permeance method is adopted for analysing the static and dynamic property of solenoid part theoretically. In addition, in this study, experiments on solenoid part were performed in order to measure the magnetic force and plunger displacement. The numerical results coincided with the experimental results. As a result, the magnetic force has the linear relation with displacement of plunger and the primary factors on the performance of PWM type high speed electromagnet are coil resistance, plunger mass, and the length of air gap between plunger and core.

• Journal of the Korean Society of Visualization
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• v.21 no.2
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• pp.8-13
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• 2023

The primary challenge in improving fuel efficiency and reducing air pollution for commercial vehicles is reducing their aerodynamic drag. Various flow control devices, such as cab-roof fairing, gap fairing, cab extender, and side skirt have been introduced to reduce drag, however, the drag reduction effect and applicability are different depending on each commercial vehicle model. To evaluate the fuel consumption of heavy vehicles, a comprehensive research approach, including drag force measurement, flow field analysis is required. This study investigated the effect of a cab extender, which installed rear region of cab, on a drag coefficient of commercial vehicle through wind tunnel experiments and CFD. The results showed that the cab extender significantly modified the flow structure around the vehicle, leading to 8.2% reduction in drag coefficient compared to the original vehicle model. These results would provide practical application for enhancing the aerodynamic performance and fuel efficiency of heavy vehicle.

• Food Science and Preservation
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• v.31 no.3
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• pp.360-373
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• 2024

Polychlorinated hydrocarbons are continuously released into the environment from various industrial processes. Trichloroethylene (TCE) and tetrachloroethylene (perchloroethylene, PCE) are of primary concern because of their large-scale production, wide industrial application, poor biodegradability, and tendency to circulate in the air and water. The common routes of human exposure to these compounds include inhalation, ingestion, and dermal adsorption. Additionally, they have been detected in various plant foods. Prolonged exposure to these contaminants is associated with certain risks. They are carcinogenic and have other toxic effects, including gastrointestinal, developmental, neurological, and hematological toxicity. To analyze these contaminants, they are generally extracted from various matrices, followed by instrumental analysis. Gas chromatography, often in combination with different detectors, is the most widely used analytical method. This review covers the toxicity, analytical methods, occurrence in foods, and risk assessment of these contaminants.

• Clean Technology
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• v.26 no.3
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• pp.211-220
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• 2020

This experimental study investigates the design parameters to achieve ultra low NOx combustion of coal using a 80 kW capacity single-burner furnace. The influence of key design parameters such as SN, overall and burner-zone equivalence ratios, primary/secondary air ratio, overfire air (OFA) ratio were tested for a total of 81 cases. The results showed that weak swirl intensity of the burner leads to higher NOx emission whereas strong swirl intensity accompanies increased CO concentration desipte lower NOx emission. Therefore, finding an appropirate swirl intensity is essential for the burner design. Larger flow rate of secondary air increased NOx emission, whereas smaller flow rate stretches the flame and increased CO emission. The lowest NOx emission of 82 ppm (6% O₂) was achieved at the optimal condition of the present burner deisgn. It is expected to furrther lower the NOx emission by introducing splitting the burner secondary air into three or four streams.

• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.33-47
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• 1998

Using a combination of an X-ray generator Installed in radiation calibration laboratory of Korea Atomic Energy Research Institute (KAERI) and a series of 8 radiators and filters described in ISO-4037, monoenergetic fluorescent X-rays from 8.6 keV to 75 keV were produced. This fluorescent X-rays generated by primary X-rays from radiator were discriminated $K_{\beta}$ lines with the aid of filter material and the only $K_{\alpha}$ X-rays were analyzed with the high purity Ge detector and portable MCA. The air kerma rates were measured with the 35 co ionization chamber and compared with the calculational results, and the beam uniformity and the scattered effects of radiation fields were also measured. The beam purities were more than 90 % for the energy range of 8.6 keV to 75 keV and the air kerma rates were from 1.91 mGy/h (radiator : Au, filter : W) to 54.2 mGy (radiator : Mo, filter : Zr) at 43 cm from center of the radiator. The effective area of beam at the measurement point of air kerma rates was 12 cm ${\times}$ 12 cm and the influence of scattered radiation was less than 3 %. The fluorescent X-rays established in this study could be used for the determination of energy response of the radiation measurement devices and the personal dosemeters in low photon energy regions.

• The Journal of Sustainable Design and Educational Environment Research
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• v.6 no.2
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• pp.66-90
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• 2007

The purpose of this study is to measure and analyze primary causes of indoor air pollution, including carbon dioxide, minute dust, and total volatile organic compounds, for each room before the beginning of a class through the time of discharge after the end of the class in general classrooms, computer rooms, and science rooms of three newly-established schools that opened in 2006, examine properties of indoor air environment in each room by educational activities at school, and determine effective management schemes; the results of this study can be summarized as follows: 1) As for implications for each item found in the mean for each place, since minute dust (PM10) was more likely to occur in time slots full of students' activities, such as a traveling class and a recess, than in the middle of a class and could be expected fully, it is necessary to make a scheme for cleaning in order to reduce minute dust within a room, for example, by usually using a vacuum cleaner indoors. 2) While carbon dioxide was expected to vary with the differences in the amount of breath between higher-graders and lower-graders in a general classroom but showed insignificant difference by grades, showing differences in pollution by four times at a maximum according to the opening of a window as expected, it is necessary to implement artificial or natural ventilation and take a positive measure, for example, by presenting a concrete ventilation scheme, in order to improve indoor air pollution at a room practice. 3) Total volatile organic compounds were found to exceed the standard by more than twice in general classrooms, science rooms, and computer rooms of the schools because of building materials, furnitures including desks and chairs, panels and boards for environment beautification, and items which could be detected even from students' clothes; while a field directly-reading tool was used, obtaining high reliability for the results, it is necessary to apply an analytical method based on process test separately for actual correct measurement if a significantly great amount of total volatile organic compounds appear as compared with other schools due to measuring expenses and consecutive measurements. 4) Since formaldehyde (HCHO) was generally found to exceed the standard in general classrooms, science rooms, and computer rooms, it is necessary to establish and operate a ventilator during a class in a computer room which requires airtightness and a science room in which an organic compound should be used for a class.

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.1
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• pp.327-353
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• 2017

The issue submitted to the Court of Justice on the merits of case C---573/13 originated from a claim brought in the context of a dispute between Air Berlin and the German Federal Union of Consumer Organisations and Associations. The challenge concerned the way in which air fares were displayed in Air Berlin's computerised booking system. The system was organised in such a way that, after selecting a date and a departure airport, one would find all possible flight connections in a summary table. However, the final price of the ticket was displayed only for the clicked connection, and not for all connections, thus preventing customers from being able to compare such price with the prices of other connections. The German Federal Union took the view that this practice did not meet the requirements laid down by Article 23 of Regulation (EC) No. 1008/2008, which requires transparency in the prices set for air services. This led the German State to bring an injunctive action to cause Air Berlin to discontinue said practice. The claim was upheld at both the application and appeal stage of the relevant proceedings. Subsequently, Air Berlin submitted the matter to the German Federal High Court, which decided to stay the proceedings and ask for a preliminary ruling from the Court of Justice as to 1. whether Article 23 of Regulation (EC) No. 1008/2008 must be interpreted as meaning that, during the computerised booking process, the final price to be paid must be indicated at all times when prices of air services are shown, including when they are shown for the first time; and 2. whether, during the computerised booking process, the final price must be indicated only for the air service specifically selected by the customer or for each air service shown. In a nutshell, the Court, by the here---discussed judgment determined that Article 23 of Regulation (EC) No. 1008/2008 must be interpreted as meaning that, in the context of a computerised air ticket booking system, the final price to be paid must be indicated not only for the air service specifically selected by the customer, but also for each air service in respect of which the fare is shown. Clearly the above judgment will place air companies under an obligation to update and adjust (when needed) their computerised ticket booking and payment systems, in consideration of the primary need for consumers to be aware at all times of the actual price payable for a ticket and be able to compare the price of the service selected with the prices for other air services in respect of which the fare is shown.