• Journal of Korea Port Economic Association
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• v.29 no.2
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• pp.159-171
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• 2013

This paper aims to analyse the relative efficiency of logistics facilities and suggest the policy alternatives for exploring and activating them. This study also divides the logistics facilities into airport terminals, logistics complexes, container terminals, and trucking freight terminals. For this purpose, the CCR-DEA as well as the BCC-DEA techniques are employed to show which part explains the primary cause of inefficiencies of each DMU(Decision Making Unit). The empirical results indicate that the efficiency of logistics complex is the lowest of all, while freight trucking terminal has the highest efficiency. This study also reveals that operation inefficiency is greater than scale inefficiency in most of DMUs, showing that much more effort be done for alleviating the cost resulting from irrational management.

• Journal of Electrochemical Science and Technology
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• v.6 no.4
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• pp.131-138
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• 2015

Electrical discharge machining is an unconventional machining process in which successive sparks applied to machine the electrically conductive materials. Any changes in electrical discharge machining parameters lead to the pieces with distinct surface roughness. The electrical discharge machining process is well applied for high hardness materials or when it is difficult to use traditional techniques to do material removing. Furthermore, this method is widely applied in industries such as aerospace, automobile, molding, and tool making. CK45 is one of the important steels in industrial and electrical discharge machining can be considered as a proper way for its machining because of high hardness of CK45 after thermal operation of the electrical discharge machining process. Optimization of surface roughness as an output parameters as well as electrical discharge machining parameters including current, voltage and frequency for electrical discharge machining of CK45 has been studied using copper tools and kerosene as the dielectric. For such a purpose and to achieve the precise statistical analysis of the experiment results design of experiment was applied while non linear regression method was chosen to assess the response of surface roughness. Then, the results were analyzed by means of ANOVA method and machining parameters with more effects on the desired outputs were determined. Finally, mathematical model obtained for surface roughness.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.5
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• pp.545-550
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• 2004

The study of available genotypes (biodiversity analysis) in bacterial communities is of growing importance in several fields such as ecology, environmental technology, clinical diagnostics, etc. These culture-independent genotyping techniques, especially amplifying 16S rRNA genes, attempt to overcome some shortcomings of conventional cultivation method. Biodiversity analysis based on molecular technique were laborious for base-calling chromatogram, trimming primer sites, correcting strand directions, electing representative operation taxonomic units (OTU), etc. Also, biologists wanted intuitively to confirm results of the above processes. For making up these demands, we developed the web application based on Folder-Process-Filter (FPF) modeling with correspondence to classical Model-View-Controller model. The model of web application leads to keep virtues of simplicity and directness for development and management of the stepwise web interfaces. The web application was developed in Perl and CGI on Linux workstation. It can be freely accessed from http://home.pusan.ac.kr/～genome/tools/rat.htm.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.2
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• pp.243-251
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• 2010

The military has been putting great efforts into applying data communication on existing voice communication systems being used in NCW(Network Centric Warfare). Data communication will be an effective choice in one of many effort to yield a minimum kill chain, comparing to legacy voice communications, when tactical units conduct their missions. However, the required budget will be enormous, in case of the replacement of a lot of legacy communication systems with new one. As a cost-effective alternative, the tactical data communication systems using the conventional radio systems instead of the development of new radio systems has been proposed. It is mandatory, though, to ensure QoS while maintaining data communication by making use of legacy radio systems already in use. This paper focuses on the performance issues experimented and analyzed for tactical data communication through the legacy radio systems as the first step towards guaranteed QoS. We have conducted various experiments such as the transmission error rate on certain tactical messages, performance evaluation of redundant transfers, the relationship between the transmission frame size and rate of error, the identification of error points in the transmission frame, and techniques to reduce the errors in both hopping and non-hopping modes. As a result of the performance experiments, The adaptive communication module which decides the redundant transmission or the Forward Error Correction(FEC) technique by analyzing channel status and current transmission status(hopping/non-hopping) of the legacy radio should be designed. the FEC technique in non-hopping, and the redundant transmission technique in hopping mode was recommended from the result of experiment with the frame size is 20bytes in non-hopping and 10Bytes frame size in hopping mode.

• Journal of the Korean Geotechnical Society
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• v.16 no.1
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• pp.227-234
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• 2000

Soilcrete has been a traditional material for pavement and soft ground improvement techniques. However, since the durability is not excellent and the quality is not consistent, it has not been used for various purposes up to date. However, with the increase of naturally oriented needs for light traffic roads such as pedestrian roads of garden, golf courses and sidewalks, the cases of the high strength soilcrete paving have been increased lately. This study aims at making a reference table of mix design in accordance with the required design specifications fur the high strength soilcrete admixtured with the pozzolanic cement by using a statistical experimental method. The treated soil is the clay which is widely found in Korea. As the results of this study, we could derive an effective reference mix design table for the clay treated with the pozzolanic cement stabilizer in accordance with the compressive strength of $50~150kg/cm^2$ soilcrete.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.3
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• pp.252-257
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• 2014

It is important to produce a provisional restoration reflecting the patient's jaw relation, occlusal plane, lip support, shape of teeth, and occlusion type for fully edentulous patients before making a definite prosthesis. The patient introduced in this study showed bad prognosis of remained tooth after severe periodontal diseases. Therefore, remaining teeth were extracted and replaced with dental implants. Provisional restorations were fabricated and the the patient's vertical and horizontal jaw relationship, occlusal plane, amount of overjet and overbite, size of teeth, and length of anterior tooth were recorded. Provisional restorations were scanned and CAD/CAM techniques were used to fabricate a monolithic zirconia bridge, which contour is identical with the provisional restorations. The patient was satisfied with the treatment results on functional, esthetic aspects and the prosthesis retained stable during the four-month clinical observation period.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.3
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• pp.208-213
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• 2013

The spectrum of physically challenged patients who visit to a dental clinic for treatments are diverse: from ones of mild disabilities, who lead their lives in a similar way of ordinary people, to others who suffer from diseases that are difficult to be diagnosed, and need medical expertise due to systemic care or special techniques and instruments because of behavior management and difficulty of treatments. The patient in this case was 25-year-old autistic male patient who visited the clinic on account of overall treatment for multiple carious lesions. He could perform normal daily life to some degree under the care of a guardian. This case report describes predicaments of making a treatment plan resulted from lack of information about disabled patients, and difficulties of proceeding treatment procedures under general anesthesia. It is considered that sufficient consultation and history taking are needed before treatment for disabled patients.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.210-217
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• 2014

This study is to present objective data for the approaches of therapeutic exercise for the correction of genu varum by making an analysis and a comparison of the hip joints' ROM and isokinetic muscles of the female college students with straight legs with those of a female college student with idiopathic genu varum. Additionally, the state of the adductor muscle's thighs and the deep muscles of the subjects with bowed legs were experimented and the equipment's effect and applicability was reviewed through the process of the movement of newly developed exercise equipment, Balloa(2013, Balloa/Adonia/Korea). As a result, a person with genu varum needs the height increasing method for increasing external rotation ROM of a hip joint and requires the exercise techniques to strengthen external rotator muscles and to inhibit the activity of internal rotator muscles of a hip joint. Balloa increases the external rotation ROM of a hip joint and strengthens gluteal muscles, deep muscles, and adductor muscles, and the equipment's function of muscle strengthening shows that the equipment is an effective corrective exercise for the patients of genu varum.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.6
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• pp.1613-1620
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• 1990

For the purpose of the study on the spray characteristics of a coaxial nozzle, the measurement of the velocity and size of droplets, concentration, and the statistical correlation coefficient between the fluctuation of the velocity and that of the corresponding drop diameter have been carried out. Various method of simultaneous measurement of velocity and drop size have been developed from LDV techniques. The technique used here belongs to the method that supposed by Yule, Holve and Self. It has the advantages of making use of a standard LDV apparatus to which minor modifications have been brought, photomultiplier is equipped with a slit instead of a pinhole and observed the measuring volume at an angle of 90.deg.. The voltage supplied by the photomultiplier has undergone an appropriate analog and digital processing. The experimental results give a good idea of the two phase flow organization and can be helpful to find a drop diffusion model when suitable data are imput.

• The Plant Pathology Journal
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• v.34 no.3
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• pp.163-170
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• 2018

Strawberry Fusarium wilt disease, caused by Fusarium oxysporum f. sp. fragariae, is the most devastating disease in strawberry production. The pathogen produces chlamydospores which tolerate against harsh environment, fungicide and survive for decades in soil. Development of detection and quantification techniques are regarded significantly in many soilborne pathogens to prevent damage from diseases. In this study, we improved specific-quantitative primers for F. oxysporum f. sp. fragariae to reveal correlation between the pathogen density and the disease severity. Standard curve $r^2$ value of the specific-quantitative primers for qRT-PCR and meting curve were over 0.99 and $80.5^{\circ}C$, respectively. Over pathogen $10^5cfu/g$ of soil was required to cause the disease in both lab and field conditions. With the minimum density to develop the wilt disease, the pathogen affected near 60% in nursery plantation. A biological control microbe agent and soil solarization reduced the pathogen population 2-fold and 1.5-fold in soil, respectively. The developed F. oxysporum f. sp. fragariae specific qRT-PCR protocol may contribute to evaluating soil healthiness and appropriate decision making to control the disease.