• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2062-2069
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• 2015

In the series hybrid active power filter (SHAPF) with magnetic flux compensation (MFC), the system current oscillate in the experimental results when adding the same phase harmonic current command in current control block. This condition endangers the security of the SHAPF. Taking the digit period average arithmetic as example, this paper explains the inter-harmonics current oscillation in the experiment. The conclusion is that the SHAPF is unstable to the inter-harmonics current in theory. Limited by the capacity of the inverter, the system current and the inverter output current do not increase to infinite. At last, some methods are proposed to solve this problem. From the practical viewpoint, the voltage feed-forward control is easy to achieve. It can suppress the current oscillation problems, and also improve the filtering effect. The feasibility of the methods is validated by both the emulation and experiment results.

• Geomechanics and Engineering
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• v.14 no.5
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• pp.439-451
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• 2018

The stress path characteristics of surrounding rock in the formation of gob were analysed and the unloading was solved. Taking Chengchao Iron Mine as the engineering background, the model for analysing the instability of deep gob was established based on the mechanism of stress relief in deep mining. The energy evolution law was investigated by introducing the local energy release rate index (LERR), and the energy criterion of instability of surrounding rock was established based on the cusp catastrophe theory. The results showed that the evolution equation of the local energy release energy of the surrounding rock was quartic function with one unknown and the release rate increased gradually during the mining. The calculation results showed that the gob was stable. The LERR per unit volume of the bottom structure was relatively smaller, which mean the stability was better. The LERR distribution showed that there was main energy release in the horizontal direction and energy concentration in the vertical direction which meet the characteristics of deep mining. In summary, this model could effectively calculate the stability of surrounding rock in the formation of gob. The LERR could reflect the dynamic process of energy release, transfer and dissipation which provided an important reference for the study of the stability of deep mined out area.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.5A
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• pp.495-501
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• 2011

IEFT proposed MIPv6 for supporting IP movement. Mobile Node is involved signaling that cause handover latency in MIPv6. Recently, Proxy Mobile IPv6 is proposed by IETF for network-based mobility management to reduce overhead in mobile node still suffers from packet loss. PMIPv6 can decrease handover latency which related overhead in MN by using network agent. Therefore, MIPSHOP Working Group proposed fast handover for PMIPv6, fu this paper, we proposed packet bicasting scheme on dual interface mobile node that can support fast handover using PMIPv6 schemes. Further, a numerical analysis is provided to show the benefits of our scheme. In the analysis, various parameters are used to compare our scheme with another procedure.

• Journal of Chest Surgery
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• v.26 no.3
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• pp.214-218
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• 1993

Extensive lymphnode dissection combined with thoracic esophagectomy improved prognosis of esophageal cancer, but there is still high postoperative recurrence rate. The immunologic capacity of esophageal cancer patients is compromised by surgery and adjuvant chemotherapy. Therefore immunological therapy for esophageal cancer patients seems rational. We have adopted postoperative immunochemotherapy since 1988. From 1988 to 1992, 31 patients with thoracic esophageal cancer underwent esophagectomy and radical lymphnode dissection, and selected patient with early esophageal cancer and unfit for thoracotomy underwent transhiatal esophagectomy in Korea University Hospital. Mean age of patients was 56 years. There were 28 squamous cell cancers, 2 adenocarcinomas and one mixed tumor. There were 4 stage I, 3 stage II, 18 stage III, and 6 stage IV cases. There were no opeartive death. Postoperative complications included anastomotic leakage in 9%, pneumonia 3 %, cylothorax 3%, recurrent laryngeal neve paresis in 3% of all patients. Curative resection group[n=19] received immunotherapy. Noncurative resection group[n=12] received postoperative immunochemotherapy, including PS-K, CDDP, and 5-FU. Operative survivors were followed from 4 months to 5 years. There were 3 lost of follow-up. Actuarial survival rate is 79% to one year, 54% to two years and 27% to five years.In conclusion, an transthoracic esophagectomy combined with systematic lymph node dissection and postoperative immunochemotherapy could improve survival rate for esophageal cancer.

• Korean Journal of Clinical Pharmacy
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• v.17 no.1
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• pp.1-5
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• 2007

A computerized chemotherapy order system (CCOS) was developed to improve the accuracy and efficiency of prescriptions for pharmacy medication scheduling at a teaching hospital, Asan Medical Center, Seoul, Korea. We evaluated the system by comparing prescriptions before and after the implementation of the system and by analyzing the effects of the system on dosing accuracy (only against 5-FU), prescription change, overdoses above maximum limit and medication disposal in non computerized program group (control group) and CCOS group. In terms of dosing accuracy, prescription error rate (%) was significantly decreased in CCOS groups compared with the control group. The rate of prescription changes was also significantly decreased in CCOS groups. Regarding overdoses above maximum limit, we found that there was no prescription order exceeding the dosage limit in CCOS groups in contrast to significant overdoses in control group. In terms of medication disposal, there was no significant difference between 2 groups. We suggest that the computerized chemotherapy order system for chemotherapy may bean important and useful tool for minimizing prescribing errors in the hospitals.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.684-690
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• 2008

In most engineering applications related with the heat conduction phenomena, a conventional Fourier heat conduction equation has been successfully applied and it has supplied quite reasonable results. However, it is well known that the Fourier heat conduction equation is failed in the application to the extremely small space and short time, in other words, a nano-scale system and a pico-second time. In this study, non-Fourier effect was evaluated in the heat conduction by considering the concept of a phase lag model. The results show the existence of a heat wave, which means that the heat is transferred with a finite speed while an infinite speed of heat transfer is assumed in the conventional Fourier heat conduction. In addition, the copper and the gold are tested to evaluate the phase lag time between the heat flux and the temperature gradient. The results show that the gold has the heat wave speed faster than that of the copper consistent with the prediction based on an actual experiment.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1123-1127
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• 2016

Chemotherapy is the primary treatment for advanced and recurrent cervical cancer. To evaluate the survival outcomes of chemotherapy and the prognostic factors in this setting, we conducted a retrospective study by reviewing the medical records of advanced and recurrent cervical cancer patients treated with systemic chemotherapy at our institute between January, 2008 and December, 2014. One hundred and seventy-three patients met the criteria with a mean age of 50.9 years. 4.1% of them were HIV positive. The most common initial stage was stage IVB (30.1%) and the most common histology was squamous cell carcinoma (68.6%). Ninety-two (53.2%) patients were previously treated with concurrent chemoradiation with 53% developing combined sites of recurrence. The median recurrence free interval was 16.7 months. Cisplatin + 5 fluorouracil (5FU) (53.2%) was the most frequent first line chemotherapy followed by carboplatin + paclitaxel (20.2%) with an objective response of 39.3%. Seventy-two patients received subsequent chemotherapy. The median overall survival of all studied patients was 13.2 months. Only a recurrence free interval of less than 12 months was an independent prognostic factor for survival outcome. In conclusion, chemotherapy treatment for advanced and recurrent cervical cancer patients showed modest efficacy with a shorter recurrence free survival less than 12 months as a significant poor prognosis factor.

• Journal of the Korean Chemical Society
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• v.61 no.5
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• pp.231-237
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• 2017

Efficiently removing Al(III) from rare earth is very significant because even trace amount of Al(III) can cause serious harm to the rare earth materials. In this paper, a nitrogen-containing activated carbon, AC-P700, was synthesized using peas as raw materials. The AC-P700 was characterized by surface area analyzer, FT-IR, and XPS methods. The adsorption and recognition properties of AC-P700 towards Al(III) were investigated, and the recognition mechanism was also analyzed. The BET special surface area of AC-P700 was $1277.1m^2{\cdot}g^{-1}$, and the average pore diameter was 1.90 nm. The AC-P700 possesses strong adsorption affinity and excellent recognition selectivity towards Al(III). The adsorption capacity for Al(III) could reach to $0.53mmol{\cdot}g^{-1}$, and relative selectivity coefficients relative to La(III) and Ce(III) is 9.6 and 8.7, respectively. Besides, AC-P700 possesses better regeneration ability and reusability.

• Computers and Concrete
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• v.25 no.5
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• pp.447-460
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• 2020

This paper deals with the characteristics of reinforcement corrosion in concrete beams under the influence of sustained loads. The evolution and distribution laws of the reinforcement corrosion were measured periodically over time. The results show that sustained load exhibits a pronounced exacerbating effect on the reinforcement corrosion, and enlarges the nonuniformity level of corrosion as the load level increases. Accompanied with the continuous formation of the rust, the corrosion rate was also observed to be highly nonlinear and time-dependent. Moreover, to visually and quantitatively analyze the distribution of reinforcement corrosion, the 3D scanning technology combined with the probability statistics analysis was adopted, and the observed nonuniformity can be well described by the Gumbel distribution. Finally, an approach based on the three-phase spherical model was proposed to estimate the reinforcement corrosion, taking account of the effects of sustained load on the changes of concrete porosity and oxygen diffusivity.

• Wind and Structures
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• v.8 no.5
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• pp.357-372
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• 2005

Mean and extreme pressure distributions on a large cantilevered flat roof model are measured in a boundary layer wind tunnel. The largest peak suction values are observed from pressure taps beneath conical "delta-wing type" corner vortices that occur for oblique winds, then the characteristics and causes of the local peak suctions are discussed in detail. Power spectra of fluctuating wind pressures measured from some typical taps located at the roof edges under different wind directions are presented, and coherence functions of fluctuating pressures are also obtained. Based on these results, it is verified that the peak suctions are highly correlated with the conical vortices. Furthermore, according to the characteristics of wind loads on the roof, an aerodynamic solution to minimize the peak suctions by venting the leading edges and the corners of the roof is recommended. The experimental results show that the suggested strategy can effectively control the generation of the conical vortices and make a reduction of 50% in mean pressures and 25% in extreme local pressures at wind sensitive locations on the roof.