• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1963-1968
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• 2004

A collection efficiency of cyclone is influenced by cut-size and slope of grade efficiency curve. It has been recognized that the collection efficiency is improved when the cut-size is reduced. However, effects of the slope have never been studied so far. In this study, we analyze a relationship between slope of grade efficiency and collection efficiency in two-stage cyclones. In single stage cyclones, higher slope cyclones have high efficiency. On the contrary to single stage cyclone, collection efficiency of two-stage cyclone have the maximum value when the first cyclone has a lower slope and second cyclone is high.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.507-513
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• 2008

In Digital Contents Computing Environment, information such as register, cache memory, and network information are hard to make certain of a real-time collection because such information collection are easily modified or disappeared. Thus, a collection of information is one of important step for computer forensics system on Digital Contents computing. In this paper, we propose information collection module, which collects variable information of server system based on memory mapping in real-time.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.5
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• pp.40-45
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• 2022

In recent years, indoor air pollution has become a crucial environmental problem. Hence, the purification of indoor air is an important issue. Typical physical filters show relatively high dust collection efficiency at a dust particle size of more than 5.0 ㎛ but extremely low efficiency at an ultrafine size of less than 2.5 ㎛. In this study, an electric field filter was proposed to capture ultrafine dust with a size of less than 5.0 ㎛. Simulation results showed that the electric field filter effectively removed ultrafine dust. In addition, sufficient dust collection efficiency was obtained even with a simple plate-shaped filter without bending the Chevron filter.

• Journal of the Korean Society for Railway
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• v.5 no.1
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• pp.10-17
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• 2002

In this study, we have developed the static and dynamic simulation program of a high speed current collection system. The catenary wire is modeled to discrete masses connected by massless strings and the pantograph is replaced with 3 d.o.f equivalent models that are composed of masses, springs and dampers. We derived partial differential equations of motion from the equivalent model and developed the simulation program. Then, we calculated the static equilibrium state of the overhead catenary and the dynamic behaviors of the high speed current collection system. The analysis results were compared with the results of GASENDO software developed at RTRI in Japan.

• Journal of Information Management
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• v.26 no.3
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• pp.54-62
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• 1995

The purpose of this study is to analyze the data of $\ulcorner$Union Catalog of Foreign Journals$\lrcorner$ Database, which has been revised and updated in 1995. The database includes 13,449 titles of foreign journals in scienc and technology which is a collection of 253 libraries in Korea. The items of analysis are nation, language, frequency, subject of each title, and also collection overlap, etc.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.1
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• pp.101-106
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• 2020

Along with dust collection efficiency, pressure loss is a very important cyclone operation factor. A severe rise in pressure loss causes the problem of cost. To solve the problem, the method connecting axial-vane type cyclones in parallel is suggested recently. The axial vane type cyclone dust collector applied in this study is a small portable type. Multiple cyclones are installed in a round type. The basic performance test on the axial vane type cyclone dust collector was conducted. As a result, the cut size reduced along with a rise in the wind velocity of the cyclone dust collector inlet. According to the test on dust collection efficiency, the effect of dust collection began to appear in the range of 3㎛ and dust collection efficiency was greatly improved at 5 ㎛. The noise of the cyclone dust collector well met the fan sound power level of KSB 6361.

• Korean Journal of Head & Neck Oncology
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• v.17 no.1
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• pp.8-12
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• 2001

It is well established that cervical lymph node metastasis is the base of clinical study on head and neck cancer. But few studies have been reported on lymph node metastasis of head and neck cancer in Korea. We consider it essential that studies on cervical lymph node metastases are conducted on pathologically proven database. Therefore, We must have database and consitent system for documentation and data collection of neck dissection specimen for prospective and retrospective study. Herein, We suggest several points from our experiences performing the proper data collection and documentation of neck dissection specimen.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.243-254
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• 1996

The main purpose of this study is to investigate the collection efficiency characteristics of a cylindrical ESP. To do that, it is necessary to analyze the electric field, gas flow field, and mechanism of particle movement by numerical simulation based on EHD model. For a gas flow field, Navier-Stokes equation involving the electric source term was solved by SIMPLE algorithm. In case of the electric field, the current continuity and electric field equations were solved by S.O.R. method. The analysis of particle movement was performed on the basis of PSI-CELL model from the Lagrangian viewpoint. The results showed that the influence on the gas flow field by the electric field is almost negligible in a cylindrical ESP. The particle drift velocity $V_P$ toward the collection surface is increased continuously by the electrostatic force due to the rise of particle charge as the particle is moving to the flow direction and the particle size becomes larger. The collection efficiency is to quitely higher with the increase of applied voltage for the same particle size, while becomes smaller as the inlet velocity is increased.

• Journal of the Korean Society for Library and Information Science
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• v.35 no.1
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• pp.163-185
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• 2001

If you can not pinpoint the location of a desired item through union catalogs and online databases, the next best thing is to identify a special collection that is likely to have it. Many libraries have many items that are recorded only on their own premises as special collections. This paper describes the value of special collections as important information sources and the guides for determining the existence and location of special collections. Women's collection development by KWIC is introduced as a case study of special collection building in the university libraries in Korea.

• International journal of advanced smart convergence
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• v.12 no.2
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• pp.173-181
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• 2023

Data collection is an essential element in the construction and operation of a smart factory. The quality of data collection is greatly influenced by network conditions, and existing wireless network systems for IoT inevitably lose data due to wireless signal strength. This data loss has contributed to increased system instability due to misinformation based on incorrect data. In this study, I designed a distributed MQTT IoT smart sensor and gateway structure that supports wireless multicasting for smooth sensor data collection. Through this, it was possible to derive significant results in the service latency and data loss rate of packets even in a wireless environment, unlike the MQTT QoS-based system. Therefore, through this study, it will be possible to implement a data collection management system optimized for the domestic smart factory manufacturing environment that can prevent data loss and delay due to abnormal data generation and minimize the input of management personnel.