• Journal of Bio-Environment Control
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• v.13 no.4
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• pp.217-225
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• 2004

This study was performed to provide the basic knowledge about the mushroom cultivation facilities. Classified current status of cultivation facilities in Gyeongnam province was investigated by questionnaire. The structure of Pleurotus eryngii cultivation facilities can be classified into the simple and permanent frame type. The simple frame structures were mostly single-span type, on the other hand, the permanent frame structures were more multi-span than simple structures. And the scale of cultivation facilities was very different regardless of structural type. But as a whole, the length, width and ridge height were prevailing approximately 20.0 m, $6.6\~7.0m$ and $4.6\~5.0m$ range, respectively. The floor area was about $132\~160\;m^2$, and floor was built with concrete to protect mushrooms from various harmful infection. The roof slope of the simple and permanent type showed about $41.5^{\circ}\;and\;18.6\~28.6^{\circ}$, respectively. The width and layer number of growing bed for mushroom cultivation were around $1.2\~1.6m$, 4 layers in common, respectively. Most of year round cultivation facilities were equipped with cooler, heater, humidifier, and ventilating fan. Hot water boiler was the most commonly used heating system, the next was electric heater and then steam boiler. The industrial air conditioner has been widely used for cooling. And humidity was controlled mostly by ultra-wave or centrifuging humidifier. But some farmers has been using nozzle system for auxiliary purpose. More then $90\%$ of the mushroom house had the independent environment control system. The inside temperature was usually controlled by sensor, but humidity and $CO_2$ concentration was controlled by timer for each growing stage. The capacity of medium bottle was generally 850 cc and 1100cc, some farms used 800 cc, 950 co and 1,250 cc. Most of mushroom producted has been usually shipped to both circulating company and joint market.

• Geotechnical Engineering
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• v.6 no.1
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• pp.35-42
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• 1990

Over the years, most pavement designs based on soil strength and permanent strain are almost independent of soil elasticity. However, it was found that plasticity and elasticity of soil have both effected on the failure of pavement structures. The elasticity of soil, hence, using the resilient modulus is reflected for recent pavement design. Although the current AASHTO specifications(1986) for pavement design had changed the soil support value to the resilient modulus, triaxial devices conducting the resilient modulus test have not been fully equipped in a great majority of laboratories. Thus, in the present work, such a resilient modulus is usually derived(from CBR, K values, etc.) by estimating equations. The purpose of this study is to evaluate the resilient modulus of weathered granite soils sampled from 4 points of the central region of Korea by means of AASHTO T 274-82. According to this, some empirical equations for predicting that of the weathered granite soil are proposed and then, the relationship to convert CBR into the resilient modulus is developed.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.6 s.52
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• pp.37-46
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• 2006

In this study, the efficacy of the newly developed smart passive control system to improve seismic performance of base isolated building structures is numerically verified. The smart passive control system consists of a magnetorheological (MR) damper and an electromagnetic induction (EMI) part. The damping characteristics of an MR damper can be controlled by the current generated in an EMI part according to the Faraday's law of electromagnetic induction. An EMI part consisting of a permanent magnet and a solenoid coil could substitute a control system including sensors, a controller and an external power supply in a conventional smart control system. The benchmark control problem for a base isolated building presented by the american society of civil engineers is considered for numerical simulation. The control performance of the smart passive control system is compared to that of the conventional smart control system using MR dampers. It is demonstrated from the numerical simulation results that the smart passive control system is useful to improve the seismic performance of base isolated buildings.

• Journal of the Korea Society of Computer and Information
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• v.21 no.5
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• pp.177-184
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• 2016

Since 1980s, 30 years has passed after issues on environmental refugee began to appear. However, why environmental refugee is not considered as refugee officially in international society? Above all, it seems that main point is the responsibility given to those developed countries if they, whom led the climate changes, officially acknowledge environmental refugee. The problem is that environmental refugee has no direct responsibility for causing climate changes. Actually. the responsibility should be granted to the developed and industrialized countries which caused climate changes. In accordance to the refugee protection system established under current international law, it is difficult to include them into refugee category and thus, they can hardly have enough support. It is urgently needed that new refugee treat which have the new standard and solution added to it shall be adopted. To allow new refugee treat to be effective it is compulsory to have constant and binding policy determination and willingness of execution from a united international organization. Of course, before this, countries should try to have common recognition on recognizing new refugee problem and its seriousness as well as solving those problems together. In reality, it is worth considering adoption of semi-forceable type of system as a more effective way, which allocates responsibility of accepting refugee by amount of carbon emitted. Also, as refugee issue has an important influence on mother company and the third countries, execution process of the system has to be defined clearly. For those permanent organizations, they should accurately define environmental factors making refugee and set standards to minimize possibility of abuse and misuse.

• Journal of Korea Multimedia Society
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• v.19 no.2
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• pp.375-385
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• 2016

Recently, several implantable hearing aids such as cochlear implant, middle ear implant, etc., which have a module receiving power and signal from outside the body, are frequently used to treat the hearing impaired patients. Most of implantable hearing aids are adopted permanent magnet pairs to couple between internal and external devices for the enhancement of power transmission. Generally, the internal device which containing the magnet in the center of receiving coil is implanted under the skin of human temporal bone. In case of MRI scanning of a patient with the implantable hearing aid, however, homogeneous magnetic fields of the MRI might be interfered by the implanted magnet. For the above reasons, the MR image is degraded by large area of artifact, so that diagnostics are almost impossible in deteriorated region. In this paper, we proposed an external coil system that can reduce the artifact of MR image due to the internal coupling magnet. By finite element analysis estimating area of MR artifact according to varying current and shape of the external coil, optimal coil parameters were extracted. Finally, the effectiveness of the proposed external coil system was verified by confirming the artifact at real MRI scan.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.2
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• pp.66-74
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• 2000

This study was carried out to introduce current status and development strategy for an environmental restoration of stream side in Japan, and to consider a methodology which could be effectively applied for the environmental restoration of stream side in Korea. The strategy prospects of environmental restoration in Japan were summarized as follows: 1. We should establish a new paradigm of forest road, forest conservation and erosion control which can emphasize the restoration of the streamside ecosystem and reduce the effects of soil movement change in the areas. And we should maintain the biotic habitats to conserve native biotic community when we practice forest road, forest conservation and erosion control works. 2. In the point of view ecological conservation aspects, we should evaluate the effects of new forest conservation and erosion control methods which is emphasized on the restoration of the streamside ecosystem to apply desirable methodology to the environmental restoration of the streamside area. 3. In the past, the objective of forest conservation and erosion control was to fix a soil by construction of permanent structures. Whereas, the direction of future's forest conservation and erosion control needs to change new forest conservation and erosion control technology to prevent large scale soil movement but allow small scale soil movement to conserve sound ecosystem and biotic habitats. 4. The restoration of the streamside ecosystem should provide continuity of the streamside environment which allows desirable biological habitats, and environmentally sound facilities to harmonize the environment.

• The Journal of Sustainable Design and Educational Environment Research
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• v.8 no.1
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• pp.23-33
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• 2009

The purpose of this study was to examine the basic academic achievement of technical high school students, their learning capability about major, their adaptability to school instruction and whether those factors of them was linked to their career in an effort to suggest workable reform measures. Technical high school seniors to grasp their basic learning capabilities and their opinions on the curricula. The findings of the study were as follows: First, the civil engineering students at technical high school weren't fully able to understand what they learned because of their poor basic achievement. They should take all the required courses to fix their academic deficiencies in the first year of high school, and client-centered additional education should be provided about particular subjects, such as mathematics, which they should learn to study their major. Second, many of the students chose technical high school through the advice of parents or since they weren't able to go onto academic high school. So they entered technical high school without knowing well about their major, and vocational education wasn't properly publicized. As students make a critical career decision in middle school, the government should build permanent pavilions for vocational-education exhibition where interested students can acquire information and explore their career without any restraints. Current fragrant vocational education that is based on experiential learning should be avoided. Third, the government substituted regular classroom teaching for field practice, and that resulted in providing just uniform instruction, destroying learning atmosphere and eventually holding teachers back from offering quality education. To remedy the situation, two different sorts of classes should be prepared. One type of classes are for college- bound students, and the others are for job-seeking students. College- bound students should receive education about humanities to improve their academic deficiencies, and job-seeking seniors should be allowed to take field-practice courses at authorized companies in the second semester. It's advisable personally and socially to help ensure their successful and immediate social adjustment.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.18 no.2
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• pp.267-276
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• 2011

Purpose: The purpose of this study was to provide data for development of the Journal of Fundamentals of Nursing through reviewing classification of sectional editorship. Method: Descriptive statistical analysis was used, to identify content then, the classifications of sectional editorship were reviewed. Results: The categories, "Basic concepts of nursing" (30.2%:17.9%), "Needs for comfort" (15.9%:13.1%), "Nursing education" (12.7%:12.7%), and "Needs for activity and exercise" (7.1%:7.1%) were most frequent through both the 1st and 2nd sectional editorship. Conclusion: Classification of sectional editorship was developed to clarify the educational purpose of fundamentals of nursing, and was modified through reflections by researchers. The current classification of sectional editorship is not a permanent formula, so using various viewpoints in further examination is needed.

• Progress in Superconductivity and Cryogenics
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• v.19 no.1
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• pp.30-35
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• 2017

The effects of the crystallographic orientation and sample thickness on the magnetic levitation forces (F) and trapped magnetic field (B) of single grain YBCO bulk superconductors were examined. Single grain YBCO samples with a (001), (110) or (100) surface were used as the test samples. The samples used for the force-distance (F-d) measurement were cooled at 77 K without a magnetic field (zero field cooling, ZFC), whereas the samples used for the B measurement were cooled under the external magnetic field of a Nd-B-Fe permanent magnet (field cooling, FC). It was found that F and B of the (001) surface were higher than those of the (110) or (100) surface, which is attributed to the higher critical current density ($J_c$) of the (001) surface. For the (001) samples with t=5-18 mm, the maximum magnetic levitation forces ($F_{max}s$) of the ZFC samples were larger than 40 N. About 80% of the applied magnetic field was trapped in the FC samples. However, the F and B decreased rapidly as t decreased below 5 mm. There exists a critical sample thickness (t=5 mm for the experimental condition of this study) for maintaining the large levitation/trapping properties, which is dependent on the material properties and magnitude of the external magnetic fields.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.237-243
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• 2015

In this paper, we consider a cascaded type of control architecture for a multi motor-based feedback control system and propose an ADC (Analog to Digital Converter) resource allocation method to efficiently utilize the limited ADC resources. The purpose of the resource allocation method is to minimize both the motor position measurement error and the d-q current measurement error. The cascaded type of control architecture is applied in parallel to each motor to independently control the speed of a motor in the multi motor control system. All the control algorithms are implemented by software using a single microcontroller without using additional microcontrollers. It is illustrated by experiments that the speed and the torque of each motor are controlled precisely by the proposed control architecture with the efficient ADC allocation method.