• Journal of Environmental Science International
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• v.27 no.2
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• pp.99-107
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• 2018

In order to design the improvement process for T-N removal, the treatment process of Suyoung, Gangbyeon, and Noxan sewage treatment plants (STP) in Busan was anlayzed. Suyoung STP shows a T-N removal efficiency of about 69.8% with MLE(Modified Ludzack ettinger) and A2O+MBR. However, it is necessary to improve the process to maintain over DO of 1 mg/L and is required to install a flow control tank to minimize the rainfall effect. Gangbyun STP shows a about 70.2% T-N removal efficiency with A2O+GFF(gravity fiber filtration). However, in order to improve T-N removal efficiency, it is needed to install MLE process to treat recycle water. Noksan STP shows a T-N removal efficiency of about 71.0% with MLE+Chemical treatment and shows stable T-N concentration in effluent. However, it is required a toxic chemical management process because bad wastewater flows into the STP, also is necessary a process improvement in order to increase internal recycling ratio. Especially, it is required a process improvement to increase HRT of nitrification tank because Suyoung and Gangbyeon STPs shows low nitrification efficiency during winter season.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.9
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• pp.605-613
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• 2010

Double skin facade(DSF) ventilated by fans consists of a normal external and an internal envelope. In this glass layer, the installed fan replaces an air inlet for the control of air flow through the cavity. The purpose of this paper is to investigate physical theory and to analyze the applicability of fans installed in a DSF. The experiment was conducted in 2 rooms. One room has a DSF with installed fans and the other one has a typical window. The room ventilated through a DSF which fans are installed was always kept warmer than the other room, ventilated directly from the outdoors. The average increase of the supplied air temperature through the DSF ventilated by fans was $6.54^{\circ}C$ at 78CMH, $6.2^{\circ}C$ at 95CMH, and $3.7^{\circ}C$ at 120CMH. As a result, the DSF with installed fans was appropriate for installation in rooms. It supplies outdoor fresh air heated through a cavity and ventilates a constant air volume.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.2
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• pp.92-102
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• 2011

Visibility of the flow of goods is an important service element when considering how to improve the quality of a logistics service. Registered mail service of Korea Post, one of logistics service providers, currently supply information on the handling of postal items, such as receipts and delivery and arrival times to customers. However, internally problems related to excessive spending on operating expenses and less reliable tracking and tracing information exist due to errors in the information acquisition and link handling processes, leading to unnecessarily duplicated tasks. Therefore, the purpose of this paper is to propose process optimization method for improving the quality of tracking and tracing information for registered mail items. We analyzed the process and information control system of the current registered mail service and identified the basic causes of the existence of less reliable tracking and tracing information. And we present optimized mail handling and information management process for removing internal problems. Test results using tracking and tracing information examples show a significant performance of the proposed method.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.96-99
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• 2012

The test facility for confirming performance of a propulsion system is essential infra-structure to develop launch vehicle system. Using the PSTC, cold flow and combustion tests are performed to the propulsion system of individual stage in launcher. Moreover the ground test for the total launching process is conducted. In order to construct the PSTC, we not only have surveyed technology of internal and external countries, but also actively use the case in terms of the system. The test facility consists of feeding system, test stand, control and measurement, and flame deflector.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.17-28
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• 2009

There are many limitations in dealing with rapidly changing traffic demand in urban cities. Thus recently, traffic operation and management skills are more emphasized rather than the expansion of traffic facilities. In particular, in the interrupted flow formed by signalized intersections, it is quite important to give optimal signal timing to each intersection with consideration of progression. However, as fixed signal times per direction can affect passing capacity in signalized intersections, the present four-signal phase including a left-turn signal has many limitations, including reduction of directional road capacity when traffic demand is increases dramatically during peak hours. Because of this problem, lots of studies about internal metering techniques for oversaturated signal control skills have progressed but these techniques are not used widely due to the absence of detectors for queue sensing in real-time signal control systems. In this research, a new methodology called the "restrictive left-turn signal control", which is already used at the intersection above Samsung subway station, is suggested in order to reduce control delay of urban arterial roads. The restrictive left-turn signal control allows a driver to make a U-turn and then a right turn instead of turning left in that intersection. With this change, the restrictive left-turn signal control can contribute to increased intersection capacity by reducing the number of signal phases and maximizing the through phase time. However, road structure and traffic conditions at the target intersections should be considered before the adoption of the proposed signal control.

• Tuberculosis and Respiratory Diseases
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• v.56 no.5
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• pp.450-464
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• 2004

Background : The FHIT (fragile histidine triad) gene is a frequent target of deletions associated with abnormal RNA and protein expression in lung cancer. Previous studies have shown FHIT gene transfer into lung cancer cell line lacking FHIT protein expression resulted in inhibition of tumor cell growth attributable to the induction of apoptosis and reversion of tumorigenecity. However, the mechanism of the tumor suppressor activity of the FHIT gene and the cellular pathways associated with its function are not completely understood. Methods : To gain insight into the biological function of FHIT, we compared the NCI-H358 cell line with its stable FHIT transfectants after treatment with cisplatin or paclitaxel. We investigated the effects of FHIT gene expression on cell proliferation, apoptosis, and activation of caspase system and Bcl-2 family. The induction of apoptosis was evaluated by using DAPI staining and flow cytometry. Activation of caspases and Bcl-2 members was evaluated by Western blot analysis. Results : A significantly increased cell death was observed in FHIT transfectants after cisplatin or paclitaxel treatment and this was attributable to the induction of apoptosis. Remarkable changes in caspases and Bcl-2 family were observed in the transfected cells as compared with the control cells after treatment with paclitaxel. Activation of caspase-3 and caspase-7 was markedly increased in cells expressing FHIT. Expression level of Bcl-2 and Bcl-xL protein was significantly decreased and that of Bax and Bad protein was significantly increased in the transfected cells. Conclusion : FHIT gene delivery into lung cancer cells results in enhanced apoptosis induced by treatment with cisplatin or paclitaxel. The data suggest that apoptosis in FHIT-expressing cells could be related to activation of caspase pathway and Bcl-2 family.

• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.90-98
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• 1998

Background : The CD4+ T-helper cells comprise functionally distinct subsets of Th1 and Th2 cells that are distinguished on the basis of differential cytokines production Th1 cells secrete interferon-$\gamma$, lymphotoxin, interleukin-2. Th2 cells produce interleukin-4, interleukin-5, interleukin-10. A previous study shown that Th2 cells and their cytokines increased in patients with atopic asthma. We compared cytokines(IL-4, IFN-$\gamma$) activity and subpopulation of T-lymphocytes in peripheral blood from atopic asthmatics versus non-asthmatics. Method: Fifteen patients with atopic asthma(nine men, six women), twelve patients with chronic bronchitis(six men, six women), five healthy persons(three men, two women) were studied. Activity of IL-4, IFN-$\gamma$ and T-cell subpopulation in peripheral blood were estimated. Results: Patients had a median age of 55yr. The mean activity of IL-4 of asthmatics was significantly increased(control $0.75{\pm}1.1pmol/L$, atopic asthmatics $3.50{\pm}0.75pmol/L$, chronic bronchitis $2.01{\pm}1.2pmol/L$), but IFN-$\gamma$ was not significantly increased. In the T lymphocyte sunsets the percent of CD62L+ T-lymphoeytes of asthmatics was not significantly increased (control $16.7{\pm}16.4%$, atopic asthmatics $24.8{\pm}23.6%$, chronic bronchitis $17.0{\pm}16.9%$). Conclusion: In this study elevated production of IL-4 was observed in atopic asthmatics. CD62L+T-lymphoeytes was not increased in atopic asthma.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.290-297
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• 1997

Background : Despite remarkable progress of understanding the pathophysiology and therapy of bronchial asthma, asthma morbidity and mortality are on the rise. Also hospitalization and attending rates of emergency department for asthma have been increasing gradually. We analyzed clinical characteristics and prognosis of patients who visited emergency room due to asthma attack in order to define clinical characteristics of these group of patients. Method : We reviewed 105 adult asthmatic patients who attended emergency department of Korea University Hospital between August 1995 and July 1996, retrospectively. Results : 103 patients(56 female, 47 males, mean age : 48.6 years) attended-68 self referral, 18 practitioner referral and 17 OPD transfer- and 86 patients(83.5%) were admitted. Attending emergncy department was clearly more frequent in December(13.6%) and May(12.6%). Time lag between onset of asthmatic attack and arrival at the hospital was $14.2{\pm}15.5$ hour and initial peak expiratory flow rate was $166.7{\pm}68.3L/min$.(43.3% predicted) The commonest cause for visiting emergency room was aggravation of asthma due to upper respiratory tract infection in mild asthmatics. About half of them had history of previous ER visits. Their prognosis was not bad, but after discharge, about half of patients escaped from OPD follow-up. Conclusion : As a group they merit detailed attention and follow up arrangement. Clinician need to monitor and review the treatment plans, the medications, the patient's management technique, and the level of asthma control. For this group, plans for longer term treatment, including asthma education program and adjustment of overall treatment plan should be made.

• The Korean Journal of Nuclear Medicine
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• v.36 no.6
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• pp.357-367
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• 2002

Purpose: While cerebral blood flow and cerebrovascular reserve could be evaluated with basal/acetazolamide Tc-99m-HMPAO SPECT in cerebrovascular disease, objective quantification is necessary to assess the efficacy of the revascularization. In this study we adopted the SPM method to quantify basal cerebral blood flow and cerebrovascular reserve on basal/acetazolamide SPECT in assessment of the patients who underwent bypass surgery for linternal carotid artery (ICA) stenosis. Materials and Methods: Twelve patients ($51{\pm}15$ years) with ICA stenosis were enrolled. Tc-99m-HMPAO basal/acetazolamide perfusion SPECT was peformed before and after bypass surgery. After spatia1 and count normalization to cerebellum, basal cerebral blood flow and cerebrovascular reserve were compared with 21 age-matched normal controls and postoperative changes of regional blood flow and reserve were assessed by Statistical Parametric Mapping method. Mean pixel values of each brain region were calculated using probabilistic anatomical map of lobes. Perfusion reserve was defined as the % changes after acetazolamide over basal counts. Results: Preoperative cerebral blood flow and cerebrovascular reserve were significantly decreased in involved ICA territory, comparing with normal control (p<0.05). Postoperative improvement of cerebral blood flow and cerebrovascular reserve was observed in grafted ICA territories, but cerebrovasculr reserve remained with significant difference with normal control. Improvement of the cerebrovascular reserve was most prominent in the superior temporal and the angular gyrus, nearest to the anastomosis sites. Conclusion: Using SPM quantification method on hasal/acetazolamide Tc-99m-HMPAO SPECT, the cerebral blood flow and cerebrovascular reserve could be assessed before revascularization and so could the efficacy of the bypass surgery.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.813-822
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• 1998

Background: Extubation is recommended to be performed at minimum pressure support (PSmin) during the pressure support ventilation (PSV). In field, physicians sometimes perform additional 1 hr T-piece trial to the patient at PSmin to reduce re-intubation risk. Although it provides confirmation of patient's breathing reserve, weaning could be delayed due to increased airway resistance by endotracheal tube. Methods: To investigate the effect of additional 1 hr T-piece trial on weaning outcome, a prospective study was done in consecutive 44 patients who had received mechanical ventilation more than 3 days. Respiratory mechanics, hemodymic, and gas exchange measurements were done and the level of PSmin was calculated using the equation (PSmin=peak inspiratory flow rate $\times$ total ventilatory system resistance) at the 15cm $H_2O$ of pressure support. At PSmin, the patients were randomized into intervention (additional 1 hr T-piece trial) and control (extubation at PSmin). The measurements were repeated at PSmm, during weaning process (in cases of intervention), and after extubation. The weaning success was defined as spontaneous breathing more than 48hr after extubation. In intervention group, failure to continue weaning process was also considered as weaning failure. Results: Thirty-six patients with 42 times weaning trial were satisfied to the protocol. Mean PSmin level was 7.6 (${\pm}1.9$)cm $H_2O$. There were no differences in total ventilation times (TVT), APACHE III score, nutritional indices, and respiratory mechanics at PSmin between 2 groups. The weaning success rate and re-intubation rate were not different between intervention group (55% and 18% in each) and control group (70% and 20% in each) at first weaning trial. Work of breathing, pressure time product, and tidal volume were aggravated during 1 hr T-piece trial compared to those of PSmin in intervention group ($10.4{\pm}1.25$ and $1.66{\pm}1.08$ J/L in work of breathing) ($191{\pm}232$ and $287{\pm}217$cm $H_2O$ s/m in pressure time product) ($0.33{\pm}0.09$ and $0.29{\pm}0.09$ L in tidal volume) (P<0.05 in each). As in whole, TVT, and tidal volume at PSmin were significantly different between the patients with weaning success ($246{\pm}195$ hr, $0.43{\pm}0.11$ L) and the those with weaning failure ($407{\pm}248$ hr, $0.35{\pm}0.10$L) (P<0.05 in each). Conclusion : There were no advantage to weaning outcome by addition of 1 hr T-piece trial compared to prompt extubation to the patient at PS min.