• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.2
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• pp.159-167
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• 2003

Cracks in reinforced concrete structures reduce overall durability by allowing the penetration of water and aggressive agents, thereby accelerating the deterioration of the reinforcing steel. Highway pavement and bridge decks are especially susceptible to this type of deterioration since these structures exhibit high rates of shrinkage and are frequently exposed to aggressive environmental conditions. The objectives of this investigation included the development of experimental procedures for assessing shrinkage cracking potential of recycled aggregate concrete, the evaluation of mix composition on shrinkage cracking potential, and the development of theoretical models to simulate early-age cracking behavior. Specifically, the influences of shrinkage-reducing admixture(SRA) and recycled aggregate concrete were investigated. The shrinkage-reducing admixture substantially reduces free shrinkage and restrains shrinkage cracking while providing similar mechanical properties. A fracture mechanics modeling approach was developed to predict the behavior of a variety of restrained concrete specimens. This modeling approach was used to successfully explain experimental results from a variety of mixture compositions. The model was used to demonstrate the influence of material and structural properties on the potential for cracking.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.1030-1035
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• 2021

Diving fishermen are demanding permission to use an inspirator that can efficiently catch Manila clam; however, coastal fishermenargue that the use of inspirator devastates the seabed and depletes fishery resources. Therefore, the aim of this study was to evaluate the fishing power of diving gears and its effect on coastal fishing grounds. The average time taken to fish in the seabed (4 m²) with a rake, water gun, and an inspirator was 11.17 min, 13.33 min and 7.81 min, respectivelyThe values of catch per unit time with a rake, water gun, and an inspirator were 3.35 kg/min, 2.26 kg/min, and 3.83 kg/min, respectively. Suspended sediments were observed the most in the water gun fishing area, and were observed more in April when fishing was not carried out than in February when fishing was carried out. However, the difference in the amount of sediment deposited in the fishing area using the three-fishing gears was very small. For an accurate analysis of the impact of the fishing gears on the seabed, supplementary tests such as grain size analysis and changes in benthic organisms need to be conducted.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.76-85
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• 2007

A reliability acceptance sampling plan (RASP) consists of a set of life test procedures and rules for eitheraccepting or rejecting a collection of items based on the sampled lifetime data. Most of the existing RASPs areconcerned with the case where test items are available at the same time. However, as in the early stage ofproduct development, it may be difficult to secure test items at the same time. In such a case, it is inevitable toconduct a life test using sequentially supplied samples.In this paper, it is assumed that test items are sequentially supplied, the lifetimes of test items follow anexponential disthbution, failures are monitored continuously, arrival times of test items are known, and thenumber of test items at each arrival time is given. Under these assumptions, RASPs are developed by deter-mining the test completion time and the critical value for the maximum likelihood estimator of the mean lifetimesuch that the producer and consumer risks are satisfied. Then, the developed plans are compared to thetraditional Type-I censored RASPs in terms of the test completion time. Computational results indicate that thetest completion time of the developed RASP is shorter than that of the traditional Type-I censored plan in mostcases considered. It is also found that the superiority of the developed RASP becomes more prominent as theinter-arrival times of test items increase and/or the total number of test items gets larger.

• The Korea Journal of Herbology
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• v.30 no.5
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• pp.1-6
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• 2015

Objectives : Vertigo is a sensation of spinning while stationary. It is commonly associated with nausea or vomiting, unsteadiness (postural instability), falls. It can affect a person's thoughts and life style. Recurrent episodes in those with vertigo are common and frequently impair the quality of life. The purpose of this study was to report the clinical effects of herbal medicine on vertigo.Methods : We employed oriental medical treatments; herbal-medication (Banhabaekchulcheonma-tang gamibang), acupuncture and moxibustion. At the same time, the blood cupping therapy in the neck area was applied. We treated the patients two or three times a week with oriental therapy methods. They took medicine three times a day after a meal. During taking medicine, we let the patients avoid fatty food, flour based food, and alcohol. We determined the course of treatment with visual analogue scale (VAS). We let them respond to a VAS item between 0 and 10 point continuously. The symptoms that we evaluated were vertigo, headache, chest discomfort, nausea and vomiting.Results : After taking treatment - acupuncture and moxibustion during some period and taking herbal-medicine, the VAS scale was gradually getting decreased. Generally the symptom of vomitting and nausea was eased at first, and then the symptom of chest discomfort, headache, vertigo was relieved.Conclusions : Banhabaekchulcheonma-tang gamibang was effective in the treatment of vertigo and its related symptoms, headache, chest discomfort, nausea and vomiting.

• Journal of Environmental Impact Assessment
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• v.12 no.4
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• pp.245-257
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• 2003

$SO_2$ concentrations in the Seoul Metropolitan Area (SMA) were predicted by the regional segment ISCST3 modeling. The SMA was segmented by three modeling regions where the weather monitoring station exists since the area of the SMA, approximately $100km{\times}100km$, is too wide to be modeled by one modeling domain. The predicted concentrations by the model were compared with the measured concentrations at 39 air monitoring stations located in the SMA to validate the ISCST3 modeling coupled with the regional segment approach. The predicted concentrations by the regional segment method showed better performance in depicting the measurements than those by the non-segment ISCST3 modeling. The correction methods of the calculated concentrations reviewed were here the correlation method by the first order linear equation and the ratio method of observed to calculated concentrations. The corrected concentrations by two methods showed good agreement with the measured data. The ratio method was, however, easily applicable to the concentration correction in case of a wide modeling region considered in this study.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.6
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• pp.565-569
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• 2001

A new surgical approach to the area of the infratemporal fossa and parapharyngeal space is described. This approach results in a wide-field exposure of the infratemporal fossa, pterygomaxillary space and parapharyngeal space. We used two osteotomies on the patient's mandible and temporary resection of zygomatic arch for superior margin of tumor. Lower lip splitting was not needed because the incision was started in the frontal scalp, curved in front of and below the external auditary canal, and extended anteriorly to the greater horn of hyoid bone on the neck along a skin crease. We had good results without sacrifice of the facial nerve, mandibular function and sensory supply of the face and oral cavity.

• KSBB Journal
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• v.25 no.1
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• pp.1-10
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• 2010

Biodiesel is a type of biofuel obtained from bioresources and able to use in diesel vehicles as an alternative/additive to petro diesel. In recent biodiesel research, there are three main issues which include high quality biodiesel, low cost feed stock and a highly efficient biodiesel production process. The sustainable production and use of biodiesel are attracting much attention in the renewable energy field. In this paper, we review some of the literatures related to environmental and economic evaluation for biodiesel production and analysis the issues including life cycle assessment (LCA), global warming potential (GWP), energy consumption, biodiesel production cost, production technologies and feedstock.

• Korean Journal of Veterinary Research
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• v.38 no.1
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• pp.91-99
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• 1998

The immunogenetic analysis was performed to characterize the Korean native chickens (KNC) determined by monoclonal antibodies specific to chicken leukocyte differentiation antigens and flow cytometry. A total of 174 chickens including 58 KNC (black, brown and darkbrown colored), 77 foreign breed (Nagoya, White Reghorn, Rhode Island and Cornish) and 39 mixed breed (19 KNC with Nagoya and 20 KNC with Rhode Island) separately growing at Animal Science and Technology Institute were examined. The proportion of cells expressing MHC class II molecule (B-L in chicken) was significantly high in KNC. Proportion of CD4+ T helper cells was also higher in KNC and two mixed breed than that in foreign breed. However, proportion of CD8+ cells and TCR1 + (${\gamma}^{\delta}$ T cell receptor) cells was the lowest among the breed examined. Otherwise, those proportions were significantly high in White leghorn and two mixed breeds with two exclusive subpopulations. The two subpopulations were also typically shown in MHC class $II^+$ cells in KNC and one mixed breed, black-colored KNC with Nagoya. Although genotypic analysis was not pursued to characterize the immunogenetic properties of KNC, difference of phenotypic expression based on leukocyte differentiation molecules could be elucidated in KNC in this study.

• Journal of the Korea Society for Simulation
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• v.24 no.4
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• pp.97-106
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• 2015

In recent, hybrid market segmentation techniques have been widely adopted, which conduct segmentation using both general variables and transaction based variables. However, the limitation of the techniques is to generate incorrect results for market segmentation even though its methodology and concept are easy to apply. In this paper, we propose a novel scheme to overcome this limitation of the hybrid techniques and to take an advantage of product information obtained by customer's transaction data. In this scheme, we first divide a whole market into several unit segments based on the general variables and then agglomerate the unit segments with higher QAP correlations. Each product network represents for purchasing patterns of its corresponding segment, thus, comparisons of QAP correlation between product networks of each segment can be a good measure to compare similarities between each segment. A case study has been conducted to validate the proposed scheme. The results show that our scheme effectively works for Internet shopping malls.

• Annals of Clinical Neurophysiology
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• v.13 no.2
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• pp.93-96
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• 2011

We present a recordings of 37-year-old woman with simultaneous ictal scalp and subdural electrodes. The ictal rhythm on subdural electrocorticography (ECoG) started earlier (median 24.5 sec) and ended later (median 2.0 sec) compared to ictal rhythm on scalp EEG. Eight ictal ECoG recordings were well localized to left temporal area, whereas ictal scalp EEG recordings were not. Our case shows the obvious timing relations between two recordings, and different electrophysiologic information about localization of ictal onset zone.