• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.80-87
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• 2015

Memristor is a new kind of memory device whose resistance varies depending upon applied charge and whose previous resistance state is preserved even when its power is off. Ordinary memristor has a nonlinear programming characteristics about time when a constant voltage is applied. For the easiness of programming, it is desirable that resistance is programmed linearly about time. We had proposed previously a memristor bridge configuration with which weight can be programmed nicely in positive, negative or zero. In memristor bridge circuit, two memristors are connected in series with different polarity. Memristors are complementary each other and it follows that the memristance variation is linear with respect to time. In this paper, the linearization effect of weight programming of memristor bridge synapse is investigated and verified about both $TiO_2$ memristor from HP and a nonlinear memristor with a window function. Memristor bridge circuit would be helpful to conduct synaptic weight programming.

• Journal of Yeungnam Medical Science
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• v.23 no.1
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• pp.36-44
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• 2006

Background: There is controversy regarding whether COX-2 specific inhibitors are associated with elevation of blood pressure. We compared the effects of aspirin, indomethacin, and celecoxib for vascular reactivity induced by phenylephrine. We also tested the effects of indomethacin and NO donor on COX-1 and COX-2 protein expression, as well as nitrite production in culture medium of vascular smooth muscle cells. Materials and Methods: In this experiment, we used the isometric tension study for vascular reactivity. After 45 minutes of pretreatment with aspirin, indomethacin, celecoxib, and phenylephrine induced contractions were tested. COX-1 and COX-2 protein expressions were analyzed by Western blot and nitrite production by the Griess reaction. Results: Although celecoxib pretreatment caused enhanced arterial contraction, aspirin pretreatment induced more potent arterial contraction than celecoxib in the isometric tension study of rabbit femoral artery. COX-1 protein expression was unchanged by indomethacin, SNP and NOR-3; COX-2 protein expression was increased by the addition of indomethacin, SNP, and NOR-3. Especially, NOR-3, a NO donor, significantly increased COX-2 protein expression with unstimulated conditions as well as LPS stimulation. Induction of nitrite production was higher with NOR-3 treatment than SNP treatment with LPS stimulation. Conclusion: These results suggest that aspirin caused more potent vascular contraction than celecoxib and indomethacin. COX-2 expression in VSMC depended on the types of NO donor and LPS stimulation.

• Journal of Yeungnam Medical Science
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• v.18 no.1
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• pp.30-38
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• 2001

Background: The purpose of this study was to evaluate the usefulness of diffusion-weighted magnetic resonance imaging for monitoring the response to radiation therapy in metastatic bone marrow of the spines. Materials and Methods: Twenty-one patients with metastatic bone marrow of the spines were examined with MRI. Diffusion-weighted and spin-echo MRI were performed in 10 patients before and after radiation therapy with or without systemic chemotherapy, and performed in 11 patients after radiation therapy alone. Follow up spin-echo and diffusion-weighted MRI were obtained at 1 to 6 months after radiation therapy according to patients' condition. The diffusion-weighted imaging sequence was based on reversed fast imaging with steady-state precession (PSIF). Signal intensity changes of the metastatic bone marrows before and after radiation therapy on conventional spin-echo sequence MRI and diffusion-weighted MRI were evaluated. Bone marrow contrast ratios and signal-to-noise ratios before and after radiation therapy of diffusion- weighted MRI were analyzed. Results: All metastatic bone marrow of the spinal bodies were hyperintense to normal bone marrow of the spinal bodies on pretreatment diffusion-weighted MRI and positive bone marrow contrast ratios(p<0.001), and hypointense to normal spinal bodies on posttreatment diffusion-weighted MRI and negative bone marrow contrast ratios(p<0.001). The signal to noise ratios after treatment decreased comparing with those of pretreatment. Decreased signal intensity of the metastatic bone marrows on diffusion-weighted MRI began to be observed at average more than one month after the initiation of the radiation therapy. Conclusion: These results suggest that diffusion-weighted MRI would be an excellent method for monitoring the response to therapy of metastatic bone marrow of the spinal bodies, however, must be investigated in a larger series of patients with longer follow up period.

• Journal of Yeungnam Medical Science
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• v.7 no.1
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• pp.29-37
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• 1990

The effects of insulin and exercise on glucose uptake of skeletal muscle were investigated in soleus muscle isolated from low dose streptozotocin induced diabetic rats in vitro. Glucose uptake was assessed by measuring $^3H$-methylglucose uptake in vitro. Basal glucose uptake in diabetes was reduced by approximately one-third of the control value($5.6{\pm}0.73{\mu}Mol$/g/20min. in diabetes versus $8.4{\pm}0.77$ in control, P<0.01). There was also a significant decrease(P<0.01) in glucose uptake of diabetes at physiologic insulin concentration ($200{\mu}IU$/ml) by 40% ($6.1{\pm}1.20$ versus $10.0{\pm}0.81$). Furthermore, maximal insulin($20000{\mu}IU$/ml)-stimulated glucose uptake was 36% lower in diabetes as compared with control($7.3{\pm}1.29$ versus $11.4{\pm}1.29$, P<0.01). In contrast, exercise(1.0km/hr, treadmill running for 45min.) effect on glucose uptake was so dramatic in diabetes that glucose uptake at basal state was 8.4+1.09 and insulin stimulated-glucose uptake were $10.2{\pm}1.47$ and $11.9{\pm}1.64$, in 200 and $20000{\mu}IU$/ml added insulin, respectively. These results suggest that insulin insensitivity develops in skeletal muscle after 2 weeks of streptozotocin-induced diabetes, but these insensitivity was recovered significantly by single session of running exercise.

• Journal of Yeungnam Medical Science
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• v.22 no.2
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• pp.199-210
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• 2005

Background: The role of obesity in prostate cancer etiology remains controversial. The aim of this study was to evaluate the relationship between obesity and prostate cancer risk. Materials and methods: Between January 2000 and June 2005, 286 patients suspected of having prostate cancer underwent prostate biopsy. The clinical records of the 286 study patients were retrospectively reviewed with regard to age, Body Mass Index (BMI), serum PSA, TRUS, and prostate biopsy results. They were stratified by BMI into three groups according to the cutoffs recommended for Asian populations: normal, BMI less than 23 $kg/m^2$; overweight, BMI 23 to 25 $kg/m^2$; and obese, BMI greater than 25 $kg/m^2$. Results: As for BMIs, 132 (46.2%) were normal, 95 (33.2%) overweight and 59 (20.6%) were obese. A total of 99 (34.6%) patients were diagnosed as having prostate cancer. In multivariate logistic regression analyses, no significant association was observed between BMI and prostate cancer detection. Conclusion: We initially hypothesized that obesity may be biologically associated with increased prostate cancer development. However, our study did not show a significant association between BMI and prostate cancer.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.292-305
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• 1995

This study was carried out to develop a Korean language version of Zung's self-rating depression scale (SDS). The subjects consisted of 173 males and 161 females drawn from various groups of the general population by a cluster of sampling methods. In order to analyze the data on depression scores, Pearson's product moment correlation coefficient method was carried out, as well as reliability and factor analysis, by the SPSS/PC+ program. The results obtained were as follows: The mean average of the total depression scores were $40.60{\pm}8.66$ for the subjects. Thirty-seven subjects (11.1%) showed high depression scores of 50 or over. Test-retest reliability(coefficient r=0.82, p <0.001), internal consistency(coefficient r=0.84, p <0.001) were satisfactory. Factor analysis using oblique technique rotation yielded five factors. The items of confusion, indecisiveness, decreased libido, diurnal variation, and psychomotor retardation were scored higher by the subjects. The items of suicidal rumination, psychomotor agitation, constipation, irritability, and weight loss were scored lower.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.12
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• pp.2335-2342
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• 2007

Laser stimulation has been widely studied and used in clinic. However, electrical response by laser stimulation on meridians has not been investigated. In this study, we compared electric potential of laser and acupuncture stimulation on meridians. We measured electric potential variation at acupoints(Samgan(LI3) and Hapgok(LI4)) on Large Intestine Meridian. In laser stimulation results, average peak electric potential is very low($7.53{\pm}3.44{\mu}V$) for before and after stimulation. However, acupuncture stimulation was performed in ground connection condition and resulted in huge variation of average peak electric potential($2.65{\pm}1.53mV$). That is, the intensity and pattern of electric potential were dependent on the ground connection condition and individual. Also, the electric potential pattern was very similar to the pattern of electric charge and discharge of capacitor. The acupuncture stimulation using a insulating needle resulted in lower average peak electric potential variation($0.25{\pm}0.16mV$) than that of acupuncture stimulation. It might present little electrical response of acupuncture stimulation using insulating needles. In point of electrical response, the laser stimulation was determined to be no acupuncture effect at meridian. Acupuncture stimulation seems to be most effective method to induce electrical response at meridians. The procedure and effect of acupuncture might be considered as energy consensus phenomenon by transportation of bio-ion charge between a practitioner and patient.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.1
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• pp.114-123
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• 2007

As a promising technology that enables ubiquitous computing and will lead the information technology industries of the next generation, the new field of sensor networks is one of the most active research topics today. From now on, each node, the network formation, and even the sensor network itself will interact with the generic network and evolve dynamically according to environmental changes, in a process of continual creation and extinction. In this paper, we propose a address-Internetworking scheme for interactive networking between a sensor network and the Internet based on the TCP port-numbers. The proposed scheme enables internetworking between a sensor network address scheme based on Zigbee and the Internet address scheme based on the Internet Protocol version 6 (IPv6). We implement the proposed address-Internetworking scheme using Berkeley TinyOS, Mica Motes, and IP. In addition we verify the proposed scheme by an interconnection experiment, which involves wireless sensor networks and the Internet, using IPv4/IPv6.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.10
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• pp.1723-1730
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• 2008

The national IT outsourcing is actively achieved centering around the manufacturing enterprise and financial institution. The If outsourcing of the public institution is generalized. The IT development and operation management task are the field in which first an outsourcing is introduced due to a factor including the technological change, the efper increase in demand, and etc. Particularly, the core business of the public institution is the public service. Therefore, the core business of the public institution can concentrate on the core business and by drastically outsourcing the etc task ran improve an efficiency. Therefore, as to the IT outsourcing, the innovative method that can enhance the quality of the public service can become. In this paper, We analyze how the Supply Administration introducing the service level agreement (SLA: Service Level Agreement) and the problem that the Samsung SDS is faced with were solved. And the practical affairs guide-line for managing elements which can minimize trial and error and successfully implement the IT outsourcing is presented.

• (The)Study of the Eastern Classic
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• no.54
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• pp.155-182
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• 2014

This study aimed to find the possibility of interactions between the Doctrine of the Mean and evolutionary biology. Between the two disciplines, there exists a huge gap such as "traditional era vs. modern times" and "humanities vs. natural science." However, this paper assumed that an analysis of their similarities and differences would allow us to find the possibility for them to interact and communicate with each other. For this purpose, the author proposed a three-step approach to studies of the following topics: human nature in step 1, validity of reasons to live in step 2 and biologically affinitive relations in step 3. The present study in step 1 pays attention to the similarities and differences between genes and in-ui-ye-ji (a set of four Confucian values: benevolence, righteousness, propriety and wisdom). This step discusses the issues of ri (principle) and ki (generative force) in Zhu Xi's theory vs. genes and vehicles in evolutionary biology, innate goodness vs. altruism of genes and in-ui-ye-ji vs. epigenetic rules. In step 2, attention is paid to the similarities and differences between natural selection and shi zhong (時中). They are discussed in terms of the upset of the law of nature vs. mutation, changes vs. evolutions and shi zhong vs. natural selection/adaptation. Step 3 focuses on the similarities and differences between species diversity and li-yi-fen-shu (one li and its many aspects). The discussion in this step addresses the issues of part or whole vs. li-yi-fen-shu, biological affinity vs. single energy and ecosystem vs. "the earth moves orderly, and everything thereon flourishes." If these studies are conducted as planned, a new direction can be set for Zhu Xi's neo-Confucianism. Further, the interaction between humanities and natural science will pave the way for us to overcome asymmetry between different disciplines.