• International Journal of Contents
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• v.2 no.4
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• pp.25-30
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• 2006

The mutual exclusion (MX) paradigm can be used as a building block in many practical problems such as group communication, atomic commitment and replicated data management where the exclusive use of an object might be useful. The problem has been widely studied in the research community since one reason for this wide interest is that many distributed protocols need a mutual exclusion protocol. However, despite its usefulness, to our knowledge there is no work that has been devoted to this problem in a mobile computing environment. In this paper, we describe a solution to the mutual exclusion problem from mobile computing systems. This solution is based on the token-based mutual exclusion algorithm.

• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.135-140
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• 2004

고혈압에서 지질대사 이상은 빈번히 나타나는 현상으로, 지질대사 이상에 관여하는 유전자들은 고혈압의 발병원인을 규명하기 위한 후보 유전자로 인식되어 왔다. 이에 본 연구에서는 paraoxonase 2(PON2) 유전자에 존재하는 Cys311Ser다형성을 유전자 표지로 이용하여 한국인 집단에서 이 유전자 표지가 고혈압과 관련성이 있는 지를 조사하고자 하였다. 연구 대상은 총 195명으로, 이들 중에서 82명은 고혈압 환자 군이었고, 나머지 113명은 정상 혈압 군이었다. PON2 유전자의 Cys311Ser 다형성을 분석하기 위해서 중합효소 연쇄반응과 제한 효소인 Dde Ⅰ처리를 수행하여 유전자형을 결정하였다. 연구 결과, Cys/Ser이 형접합체를 갖는 사람들이 고혈압군에서 유의하게 높은 빈도로 나타났으며(P<0.05),다른 신체 계측치 및 혈청내 지질 농도와는 유의한 관련성을 나타내지 않았다. 본 연구에서 관찰된 이러한 관련성이 기능적인 연관인지 혹은 연관불평형에 의한 결과인지에 대해서는 보다 더 많은 연구 대상을 이용한 추시를 통해 밝혀질 수 있을 것으로 생각된다.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2030-2035
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• 2005

In this paper, we study the distributed coordination of a set of synchronous, anonymous, memoryless mobile robots that can freely move on a two-dimensional plane but are unable to communicate directly. Based on this model, we analyze the application problem that consists in having a group of robots form a barricade line to protect from car traffic a crowd of demonstrators parading on the street. For the sake of robustness, we privilege fully decentralized solutions to the problem. In particular, we give a self-stabilizing distributed algorithm to address the problem, in this presentation

• Journal of Magnetics
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• v.20 no.3
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• pp.258-264
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• 2015

In this paper, an adequate B-H curve extrapolation method is proposed and its reliability is verified through experiments. A method is developed to estimate the magnetic saturation induction from the density of the lamination core and electrical resistivity. The magnetic saturation induction of electrical steels measured using a vibration sample magnetometer are compared with the analytical results to validate the accuracy of the proposed estimation method. It is found that the predicted error in the magnetic saturation induction of the electrical steels are approximately 1.2% when the proposed method is used. The performance of interior permanent magnet synchronous motors that applies the proposed method are evaluated via 2D nonlinear finite element analysis and through experiments. Based on the obtained results, the extrapolated B-H curves from the estimated saturation induction can be used for various analyses in saturation region.

• Journal of Biomedical Engineering Research
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• v.17 no.2
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• pp.179-188
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• 1996

A clinically oriented 32-channel electroencephalogram (EEG) and evoked potential (EP) mapping system has been developed EEG and EP signals acquired from 32-channel electrodes attached on the heroid surface are amplified by a pre-amplifier which is separated from main amplifier and is located near the patient to reduce signal attenuation and noise contamination between electrodes and the amplifier. The amplified signals are further amplified by a main amplifier where various filtering and gain contr61 are achieved An automatic artifact rejection scheme is employed using neural network-based EEG and artifact classifier, by which examination time is substantially reduce4 The continuously measured EEG sigrlals are used for spectral mapping, and auditory and visual evoked potentials measured in synchronous to the auditory and visual stimuli are used for temporal evoked potential mapping. A user-friendly graphical interface based on the Microsoft Window 3.1 is developed for the operation of the system. Statistical databases for comparisons of group and individual are included to support a statistically-based diagnosis.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.149-155
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• 2001

Eighty-one workers including 38 employees directly incinerating industry wastes were recruited from a company located in South Korea. To evaluate the association between urinary 1-hydroxypyrene glucuronide (1-OHPG) levels, as internal dose of polycyclic aromatic hydrocarbon (PAH) exposure, and glycophorin A (GPA) mutation frequency, as an early biologic effect indicator. Urinary 1-OHPG levels were measured by synchronous fluorescence spectroscopy after immunoaffinity purification using monoclonal antibody 8E11. Erythrocyte GPA variant frequency (NN or NO) was assessed in MN heterozygotes with a flow cytometic assay. The GSTM1 and GSTT1 genotypes were assessed by a multiplex PCR method. The GPA NN phenotype frequency was higher in occupationally exposed group (n=14, mean$\pm$S.D. 6.6$\pm$12.0 in 10/SUP 6/ erythrocyte cells) than in non-exposed group (n=22, 2.1$\pm$3.5). Similarly, the GPA(NO or NN) phenotype frequency was higher in exposed group (n=14, 9.7$\pm$17.3) than non-exposed group (n=22, 4.2$\pm$6.3). The above differences failed to reach statistical significance, but a significant increase was seen in GPA variant frequency levels with increase in urinary 1-OHPG levels (Spearman's correlation: p=0.06 (NO), p=0.07 (NO or NN)). When this association was evaluated by GSTM1 genotype status, the association between GPA mutation and urinary 1-OHPG levels was stronger in individuals with GSTM1 present genotype (Spearmans correlation; r=0.50, p=0.02). These results suggest that the association between urinary 1-OHPG and GPA mutation is be modulated by the GSTM1 genotype.

• Clinical and Experimental Reproductive Medicine
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• v.23 no.1
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• pp.51-59
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• 1996

Controlled Ovarian hyperstimulation(COH) is generally used to obtain synchronous high quality oocytes in in vitro fertilization-embryo transfer(IVF-ET). Many investigators have studied the relationship between serum hormone levels and outcomes of IVF-ET because there is no accurate estimation method of oocyte quality. Early premature luteinization of follicles before oocyte retrieval is the most troublesome problem in COH for IVF-ET. Gonadotropin-releasing hormone agonists(GnRH-a) are used as adjuncts with gonadotropins for COH in patients undergoing in IVF. The possible benefits of GnRH-a pretreatment include improving oocyte quality, allowing a more synchronous cohort of follicles to be recruited, and preventing premature lueinization hormone surges. In COH of IVF cycles, we investigated whether an elevated progesterone(P4) level on the day of human chorionic gonadotropin(hCG) administration indicates premature luteinization and is associated with a lower fertilization rate. Many investigators have studied that the lower fertilization rates seen in patients with elevated P4 levels might result from an adverse effect of P4 on the oocytes. We hypothesizes that serum P4 levels around the day of hCG may be helpful prediction of out come in IVF-ET cycles. Success rates after COH of IVF-ET cycles are dependent upon many variable factors. Follicular factors including the number of follicles, follicular diameters and especially serum estradiol(E2) levels as an indirect measurement of follicular function and guality have been thought to influence the outcomes of IVF-ET. To assess whether serum P4 and E2 levels affect the fertilization and pregnancy rate, we reviewed the stimulation cycles of 113 patients (119 cycles) undergoing IVF-ET with short protocol with GnRH-a, from March 1993 to August 1994 retrospectively. The serum P4 and E2 levels were compared on the day of hCG in the pregnant group, 45 patients(47 cycles) and in the non-pregnant group, 68 patients (72 cycles) respectively. The serum E2 level in non-pregnant group was $1367{\pm}875.8$ pg/ml which was significantly lower than that of pregnant group, $1643{\pm}987.9$ pg/ml( p< 0.01 ). And the serum P4 level in non-pregnant group was $2.1{\pm}1.4$ ng/ml which was significantly higher than that of pregnant group, $1.0{\pm}0.7$ ng/ml( p< 0.001 ). The fertilization rate was $61.3{\pm}21.3%$ in pregnant group which was higher than that of non-pregnant group, $41.1{\pm}20.2%$ (p< 0.01). We suggest that the serum levels of P4 and E2 on the day of hCG administration are additional parameters that predict the outcomes of IVF-ET cycles.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2377-2381
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• 2013

A total of 285 patients with stage Ib2 and IIa2 cervical cancer were categorized into three groups, and received preoperative neoadjuvant chemotherapy combined with vaginal intracavitary irradiation, neoadjuvant chemotherapy alone or radiotherapy, respectively. The effective rate of 70.6 % in group 1 was much higher than 41.4% in group 2 (P=0.000) and 46.9 % in group 3 (P=0.000); The percentage of patients receiving postoperative adjuvant therapy was 44.1% in group 1, much lower than 67.8% in group 2 (P=0.001) and 64.6% in group 3 (P=0.004); The percentage of patients with no postoperative risk factor in group 1 was 52.0%, much higher than 32.2% in group 2 (P=0.006) and 35.4% in group 3 (P=0.019); The occurrence rate of surgery-related complications in groups 1, 2 and 3 were 29.4%, 28.7%, and 33.3%, respectively, with no statistical differences among the groups (P=0.981). Regarding preoperative neoadjuvant complications, none were obvious in group 3, while occurrence rates of myelosuppression in groups 1 and 2 were 89.1% and 86.6%, of nausea and vomitting were 78.4% and 78.2%, but without significant differences (all P>0.05). Among 166 patients who received postoperative adjuvant therapy in the three groups, the occurrence rates were: 65.4%, 64.3% and 61.1% respectively for myelosuppression; 42.3%, 38.1%, and 38.9% for nausea and vomiting; 9.6%, 9.5% and 9.7% for urocystitis; and 63.5%, 69.0% and 65.3% enteritis and rectitis. There were no statistically significant differences among them (all P>0.05). The five-year disease-free survival rates (DFS) in groups 1, 2, 3 were 78.3%, 75.1%, 80.9%, respectively; the five-year overall survival rates (OS) were 81.4%, 78.2%, and 81.1%, respectively. The five-year OS of 166 patients receiving postoperative in the three groups were 72.4%, 69.5%, and 71.8%, respectively, with no significant variation (all P>0.05). Although there were no differences among three groups in DFS and OS, preoperative neoadjuvant chemotherapy combined with intracavitary radiotherapy may increase the effective rate and the percentage of patients with no postoperative risk factors and decrease the percentage of patients receiving postoperative adjuvant therapy, thereby decreasing complications indirectly and increasing quality of life.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.4
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• pp.369-380
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• 2003

With the proliferation of a wireless support and the advances of mobile devices, there is a growing need of making it available for a wireless network as well. Low bandwidth of a wireless network is one of the major issues that should be considered for extending a synchronous collaboration system developed for a wired network to supuort a wireless network. We propose a priority-based view synchronization scheme, exploiting the relaxed synchronization. The proposed scheme leverages the fact that mobile users need not have the exactly same view as the users in a wired network since they usually have a limited screen size and thus focus only on part of a whole document. We evaluate the performance of a simple group editor with the propose scheme using ns -2. The performance results show that the proposed scheme keeps the message transmission delay low so that mobile users can have synchronous colloboration with wired users without signification delay. The proposed scheme is designed and implemented as a framework to support various kinds of realtime groupware applications, exploiting the existing groupware framework, Habanero. As a client program, we implemented a simple group text editor.

• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.192-202
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• 2000

Reproductive biology of the slimy, Leiognathus nuchalis was investigated by means of histological methods. Sex ratio was 1.81 : 1 in female to male. Developmental pattern of oocytes was group-synchronous. Testicular structure was restricted spermatogonial testis-type of tubular testis. The size of first group maturity is 7.5 cm in total length. Gonadosomatic index(GSI) of female was the highest in July(12.83) and the lowest in September(1.08). GSI of male was the highest in June(19.0) and the lowest in October(0.24). Hepatosomatic index(HSI) of female showed to be positively correlated with GSI. Thoracic spot index(TSI) showed to be the minimum value from May to July when the maturation and ripe season of gonad. Reproductive cycle of female could be classified into the growing(March~May), maturation(May~June), ripe and spent(June~August), recovery(August~November), and resting stage(November~March). Reproductive cycle of male could be classified into the multiplicative and growing(January~April), maturation(April~May), ripe and spent(June~August), recovery(August~October), and resting stage(October~December).