• Composites Research
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• v.15 no.1
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• pp.21-31
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• 2002

To overcome the disadvantages of conventional excavation technology various trenchless (or excavation free, or no-dig) repair-reinforcement technologies have been developed and tried. But trenchless technologies so far developed have some drawbacks such as high cost and inconvenience of operation. In this study, a repairing-reinforcing process for underground pipes with glass fiber fabric polymer composites using VARTM (Vacuum Assisted Resin Transfer Molding) has been developed. The developed process requires shorter operation time and lower cost with smaller and simpler operating equipments than those of the conventional trenchless technologies. For the reliable operation of the developed method, a simple method to apply pressure and vacuum to the reinforcement was devised and flexible mold technology was tried. Also, resin filling and cure status during RTM process were monitored with a commercial dielectrometry cure monitoring system, LACOMCURE. From the investigation, it has been found that the developed repairing-reinforcing technology with appropriate process variables and on-line cure monitoring has many advantages over conventional methods.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.5
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• pp.353-358
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• 2011

In this study, ammonia removal characteristics in membrane contactor system under various operating conditions were evaluated. The mass transfer coefficient was used to quantitatively compare the effect of various operation conditions on ammonia removal efficiency. Effective removal of ammonia was possible with the tubular PTFE membrane contactor system at all tested conditions. Among the various operation parameters, contact time and solution pH showed significant effect on ammonia removal mechanism. Overall ammonia removal rate was not significantly affected by influent suspended solution concentration unlike other pressure driven membrane filtration processes. Also the osmotic distillation phenomena which deteriorate the mass transfer efficiency can be minimized by preheating of strip solution. Membrane contactor system can be a possible alternative to treat high strength nitrogen wastewater by optimizing operation conditions such as stripping solution flow rate, influent wastewater temperature, and influent pH.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.6
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• pp.1166-1174
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• 2004

In this paper, a design of RISC-based transmission wrapper processor for TCP/IP protocol stack is described. The processor consists of input and output buffer memory with dual bank structure, 32-bit RISC microprocessor core, DMA unit with on-the-fly checksum capability, and memory module. To handle the various modes of TCP/IP protocol, hardware-software codesign approach based on RISC processor is used rather than the conventional state machine design. To eliminate large delay time due to sequential executions of data transfer and checksum operation, DMA module which can execute the checksum operation along with data transfer operation is adopted. The designed processor exclusive of variable-size input/output buffer consists of about 23,700 gates and its maximum operating frequency is about 167MHz under 0.35${\mu}m$ CMOS technology.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.411-422
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• 2000

The purpose of this study is to identify the difference of emergency care conditions where the nurse is posted in the 119 relief squard or not. The data composed a total of 777 cases of emergency activity of one police stand in Seoul during March, June. September and December in 1998. The results of this study were as follows: 1. The age of the subjects was 20-60 age 54.3%, over 60 age 35.4% with an average age of 50.2. Among them men were 55.0%, the unemployed were 60.8%. The place of the occurrence of an accident was the house, 49.7% and the cause as illness was 59.6%. 2. The main symtom was pain the 36.2% the main consciousness state was alert 76.9%: The state of the patients as chronic was 59.6%. 3. The consulting hospital of the 119 relief squad as a third medical center was 79.9%. The distance to the medical center as less than 5 km was 77.2%, and an average transfer distance was 5.38 km. The cases of doctor guided emergency care was 0.9%, the cases that had posted nurses in 119 relief squads was 48.6%. 4. The case of the best emergency care operation was difficulty in breathing, 62.1% and the second was unconsciousness, 46.1 %. The more serious the consciousness state, the higher the rate of emergency care operation. There wasn't any difference in emergency care operation concerning transfer distance. 5. The cases that had the posted nurses was 19.1%, the cases of no nurse was 11.7% among the cases of emergency care operation during transfering; the cases that had posted nurses had the higher emergency care operation. (p<0.05). Airway maintenance was 14.8% in cases that had the posted nurses, while in the cases of no nurse, 10.9%; and oxygen inspiration was 16.0% in cases that had the posted nurses while in the cases of no nurse 7.6% (p<0.01); spinal fixation was 6.6% in cases that had the posted nurses while in the cases of no nurse 4.6%(p<0.05). With these results, we can conclude that the cases that had the posted nurse showed higher emergency care operation.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.1
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• pp.1-8
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• 2011

Controlling industrial vehicle operated by human in warehouse was not simple since the information transfer for controlling the vehicle was not easy. However, as the technology for the WMS (Warehouse Management System) has been advanced and the PDA (Personal Digital Assistant) has come into wide use in a workplace, the control of man-operated vehicle became less difficult as do to AGVS (Automated Guided Vehicle System). This study examines the ways to improve the efficiency of warehouse operation through introducing rule of task assignment for the vehicles, particularly forklift. This study, basically, refer to AGV operation policy because a great number of studies for AGV dispatching rule have been done and the mechanism for the controlling vehicles is very similar. The workers in field prefer to simple dispatching rules such as Shortest Retrieval Time First (SRTF), Shortest Travel Time First (STTF), and Longest Waiting Time First (LWTF). However, these rules have potential disadvantage. Thus, several rules made up by combining rules mentioned above are introduced and these new rules use threshold value or evaluation formula. The effectiveness of these new rules are tested by simulation and the results are compared. This study proposes favorable dispatching rules for forklift in warehouse for the efficiency of the vehicle operation and stability of service level.

• The Journal of Society for e-Business Studies
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• v.19 no.2
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• pp.75-93
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• 2014

We deal with the design of the effective block logistics operating system in shipyard. The block logistics operation is one of the critical managerial problems in shipbuilding. The block logistics operation in shipyard consists of storage operation for temporary storage in the limited storage area and transfer equipment operation of blocks from the given storage area to next process according to the block production schedule. We propose a design method of block logistics operating system based on the axiomatic design and IDEF0 method. As a result of axiomatic design, system functions are determined regarding implementation sequence. We validated the proposed design by implementation of a block logistics operating system for a large scale shipyard.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.12
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• pp.1139-1144
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• 2005

This study has been performed to investigate the thermal performance of variable conductance heat pipe (VCHP) with meshed wick. The length of condenser portion in a VCHP is varied by the expansion of inert gas with the operation temperature, and the heat transport capacity is thus varied with the operating temperature. In this study, numerical evaluation of the VCHP is made for the thermal performance of VCHP, based on the diffusion model of inert gas. Water is used as a working fluid and nitrogen as a control inert gas in the copper tube. As a result, the thermal performance of VCHP has been compared with that of constant conductance heat pipe (CCHP) according to the variation of operation temperature. Maximum heat transport capacity of VCHP is mainly presented for operation temperature and the variation of operation temperature is also presented for heat transfer rate of VCHP.

• Nuclear Engineering and Technology
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• v.54 no.2
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• pp.644-652
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• 2022

During the pyroprocessing operation, various signals can be collected by process monitoring (PM). These signals are utilized to diagnose process states. In this study, feasibility of using PM for nuclear safeguards of electrorefining operation was examined based on the use of machine learning for detecting off-normal operations. The off-normal operation, in this study, is defined as co-deposition of key elements through reduction on cathode. The monitored process signal selected for PM was cathode potential. The necessary data were produced through electrodeposition experiments in a laboratory molten salt system. Model-based cathodic surface area data were also generated and used to support model development. Computer models for classification were developed using a series of recurrent neural network architectures. The concept of transfer learning was also employed by combining pre-training and fine-tuning to minimize data requirement for training. The resulting models were found to classify the normal and the off-normal operation states with a 95% accuracy. With the availability of more process data, the approach is expected to have higher reliability.

• The Journal of Economics, Marketing and Management
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• v.10 no.1
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• pp.15-26
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• 2022

Purpose: The purpose of this study is to analyze the method of calculating the usage fee, rent, and lease rights of public goods necessary for the operation and management of the underground shopping mall, and to suggest systematic improvement points for the operation of the underground shopping mall. Data and Methodology: First, ordinances and regulations related to common property were investigated. Second, previous studies were analyzed. A survey was conducted with five questions that conflict with the interests of underground shopping mall merchants among the ordinances and operating systems related to the current underground shopping malls' common property. Results: Underpass merchants wanted monthly payment for the use of common property, and merchant organizations wanted to limit the increase rate with the right to use. They asked for the property value due to donation to be excluded from the loan fee, they wanted to revise the Common Property Act on the transfer of lease rights, and they wanted to revise the loan contract renewal period. Conclusion: There is a need to improve the laws and systems for underground shopping malls, and it will have to be negotiated according to the opinions of the merchants gathered among them, and it will have to be implemented in stages in the long term.

• Journal of Korean Academy of Nursing
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• v.28 no.1
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• pp.117-131
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• 1998

The purpose of this study was to develop a critical pathway for case management for patients who have received Coronary Artery Bypass Graft (CABG) because of Ischemic Heart Disease(IHD) which is a factor of rising medical expenses. For this study. a conceptual framework was developed through a review of the literature including six critical pathways which are currently being used in USA. In order to identify the overall service contents required by these patients and to draw up a preliminary critical pathway, 30 cases of medical records of patients who had CABG because of IHD between January, 1995 to June. 1996 at the Cardiovascular Center of Yonsei Medical Center in Seoul were analyzed. An expert validity test was done for the preliminary critical pathway and clinical validity test was also done using seven IHD patients with CABG between November 11 and 23, 1996. After these processes. the final critical pathway was developed. The results of this study are summarized as follows : 1. The vertical axis of the critical pathway includes the following eight items : tests, nutrition, medications, consultations, activity, assessments, treatments, education discharge planning and the horizontal axis includes the time from the start of hospitalization to discharge. 2. Analysis of the 30 medical records indicated that the average length of stay was 20.2days with the average length of stay from hospitalization day to operation day being 6.2 days, and the average length of stay from operation day to discharge day was 13. 9 days. Analysis of the service contents showed that the horizontal axis of the preliminary critical pathway was set from hospitalization to the 14th post operation day and the vertical axis was set to include eight items, the contents which ought to have occurred, according to the time frames of the horizontal axis. 3. As a result of the experts validity, it was found that among the total of 571 items. there was over 83% agreement for 482 items, less than 83% for 89 items, which were then deleted and a revision of the critical pathway was done. 4. A clinical validity test was done using seven IHD patients with CABG. During the process, three patients were deleted because they were out of the criteria the investigator set. Finally, four patients were used. The result of study indicated that only one patient was discharged on the tenth post operation day, which was one day later than the expected day. Three patients were discharged later than the expected day from three days to nine days. All the cases progressed on schedule until the operation day and the first post operation day, but from the second post operation days, there were differences between the critical pathway and the actual practice. The differences came from tests, assessments, and treatments. 5. On the basis of the results of the clinical validity test. the following revisions in the final critical pathway were made : the transfer from ICU to step down ward would be the second post operation day, and the transfer to a general ward, the fifth post operation day, for patients who complained of lack of sleep from the fifth post operation day to discharge, a sleeping pill would be prescribed, skin observations would be performed routinely from immediately after the operation until the third post operation day, and would continue if there was a sign of skin injury on the fourth post operation day, and assessment of chest pain would be done from the third post operation day, and the “stairs climbing” item, expected to be done on the ninth post operation day would be deleted. In conclusion, this critical pathway is partially applicable to the care of patients with CABG but there are some parts needed to be further investigated.