• Journal of Internet Computing and Services
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• v.8 no.5
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• pp.109-116
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• 2007

Nowadays, with the proliferation of Web services, developer and user can implement a complex application by composing registered Web services. In this trend, the quality of service of a composite Web service is of crucial importance for today's Service Oriented Computing (SOC) environment. But the global optimization of a composite Web service satisfying given QoS is classified to NP-hard problem. To solve this problem, we propose K-way Super node approach and show the effect of it from experimental results.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.17-29
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• 1986

The present study was carried out to observe the effect of triiodothyronine on heart, one of the target organ of thyroid hormone. There are many reports that tachycardia, arrythmia, and agumentation of sodium, potassium pump activity are caused in hyperthyroid animal. To examine these cardiac positive chronotropic effects on sinoatrial (SA) node and atrial muscle, hyperthyroid state was induced experimentally by the injecion of 3,3',5-1-triiodothyronine $(T_3)$ in $3{\sim}6$ month-old rabbits. Then intracellular recordings by inserting glass microelectrode into cell were obtained in SA node and atrial muscle. The results can be summarized as follows : 1) Heartbeat was increased from $169.6{\pm}28.0\;to\;264.2{\pm}18.0$ beats per minute, while body weight was decreased to 68f of the initial body weight (Day 1). 2) In experimental group, the duration of action potential at 80% repolarization was decreased from $148.0{\pm}29.1\;to\;107{\pm}13.6msec$. This suggested the increase heartbeat. 3) The firing rate in hyperthyroid group markedly reduced under the 15 mM potassium Tyrode (p<0.005). 4) In hyperthyroid group, depolarization of atrial muscle cell was lowered significantly in 15 mM (p<0.05), 20 mM (p<0.05) potassium Tyrode solution. 5) Sodium-potassium pump activities in experimental group were higher than those in control group in both SA node (p<0. 1) and atrial muscle (p<0.025). 6) In lower concentration of $MnCl_2$, the excitability of SA node in hyperthyroid group was decreased more than that in control group. Effective inhibitory dose $(ID_{50})$ as 0.6 mM in hyperthyroid statd and 1.1 mM in control group.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.3 s.303
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• pp.1-8
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• 2005

At IETF (Internet Engineering Task Force), recently RFC3775, RFC3776 documents about the mobile IPv6 were standardized by IETF (Internet Engineering Task Force). Those specifications propose that during the roaming, the mobile node sends securely the binding update to the home agent and the correspondent node after setting the security association between Mobile Node and Home Agent. But there is no secure bootstrapping method between a mobile node and a home agent at the two RFC documents. This paper proposed a method for the secure bootstrapping between a mobile node and a home agent. This makes the authentication, binding update, home agent assignment, security association distribution through the AAA-based secure channel between mobile node and home agent. And the proposed method was analyzed in the view of the procedure, round trip and security strength.

• Journal of Mechanical Science and Technology
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• v.14 no.9
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• pp.978-984
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• 2000

The aim of this study is to investigate the ductile fracture behaviour under Mode I loading using SA533B pressure vessel steel. Experiments consist of the Round Notch Bar Test (RNB), Single Edge Crack Bending Test (SECB), and V-Notch Bar Test (VNB). Results from the RNB test were used to tune the damage modelling constant. The other tests were performed to acquire the J-resistance curves and to confirm the damage constants. Microstructural observation includes the measurement of crack profile to obtain the roughness parameter. Finally, simulation using Rousellier Ductile Damage Theory (RDDT) was carried out with 4-node quadrilateral element ($L_c=0.25\;mm$). For the crack advance, the failed element removal technique was adopted with a ${\beta}$ criterion. In conclusion, the predicted simulation using RDDT showed a good agreement with the experimental results. A trial using a roughness parameter was made for a new evaluation of J-resistance curve, which is more conservative than the conventional one.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.04a
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• pp.233-236
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• 2002

본 논문은 인터넷상에서 다양한 매체를 이용한 서비스를 제공할 때 생길 수 있는 긴 사용자-서버간 지연, 엄청난 서버의 부하, 네트워크 자원의 비효율적 사용과 같은 문제점들을 위한 개선된 방법으로 사용자에 가까운 복수의 노드들을 두어 서버에서 전송된 데이터를 분산 저장하는 방법에 대해 다루고 있다. 새로운 분산 Proxy 기법은 VOD 서비스를 원하는 사용자들이 통일한 아이템에 대한 요청이 많은 서비스 패턴을 분석해서, 중복된 네트워크 부하는 줄이는 과정을 수행한다. 사용자가 요청한 영화는 서버에서 전송을 받는데 이때, HEN(Head-End-Node)에 구현된 여러 Proxy에 아이템의 일부를 나누어 저장하고 이에 대한 정보 보관과 제어를 SA(Switching Agent)가 하게 된다. 사용자가 서비스를 요청할 경우 SA의 제어 하에 분산 Proxy에 교호적으로 접속을 하여 저장되어 있는 부분적인 데이터들을 서비스 받도록 한다. 이때 Proxy에 새로운 데이터 블록을 저장할 때는 부족한 저장공간으로 인해 LRU(Least Recently Used), LFU(Least Frequently Used), 또는 이들을 복합한 Hybrid 정책을 사용한다.

• Journal of the Korea Society of Computer and Information
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• v.11 no.1 s.39
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• pp.97-105
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• 2006

Over the last several years, studies on spatial index have increased in proportion to the increase in the spatial data. Most of these studies, however were on the indices based on R-tree by adding or changing some options, and there are a few studies on how to increase the search performance of the spatial data by compressing an MBR. This study was conducted in order to propose a new MBR compression scheme, SA(Semi-Approximation). The basic idea of this paper is the compression of MBRs in a spatial index. Since SA decreases the keys of MBRs, the enlargements of QMBR in half and increases the utilization of nodes, the SA heightens the overall search performance. The study analyzes mathematically the number of node accesses in a 2D space and evaluates the performance of the SA using the real data on location information. The results show that the proposed scheme has increased performance, higher than that of the pre-established schemes on compression of MBR.

• Journal of Chest Surgery
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• v.18 no.1
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• pp.1-6
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• 1985

Isolated sinus node cells of the rabbit were used to assess the effects of extracellular Na, K, Ca and Mg concentrations on cardiac pacemaker activity. With intracellular glass micro-electrodes spontaneous action potentials of SA node were recorded and the effects of various ions and their blockers were analyzed in terms of the cycle length, the amplitude and the duration of action potentials, the results obtained were as follows. 1. Sodium reduction [up to 30%] decreased the amplitude of action potential and lengthened the cycle length. TTX, specific blocker of Na channel slightly lengthened the cycle length. 2. Increasing potassium ion concentration, the duration of action potential decreased and the frequency increased in 6mM, however, spontaneous action potential was stopped in 24 mM. Barium ion known to be decreasing K conductance increased the duration of action potential but no significant change in the cycle length was noticed. 3. Calcium ion has shortening effect on the duration and the cycle length of action potential but not with dose-dependent manner. Cadmium ion .[0.02mM] lengthened cycle length and the duration of action potential. 4. Increasing the concentration of magnesium ion the cycle length was lengthened, significantly.

• The Korean Journal of Nuclear Medicine
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• v.34 no.6
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• pp.478-486
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• 2000

Purpose: The sentinel lymph node is defined as the first draining node from a primary tumor and reflects the histologic feature of the remainder of the lymphatic basin status. The aim of this study was to evaluate the usefulness of lymphoscintigraphy and intraoperative radioguided gamma probe for identification and removal of sentinel lymph node in breast cancer. Materials and Methods: Lymphoscintigraphy was performed preoperatively in 15 patients with biopsy proven primary breast cancer. Tc-99m antimony sulfide colloid was injected intradermally at four points around the tumor. Imaging acquisition included dynamic imaging, followed by early and late static images at 2 hours. The sentinel lymph node criteria on lymphoscintigraphy is the first node of the highest uptake in early and late static images. We tagged the node emitting the highest activity both in vivo and ex vivo. Histologic study for sentinel and axillary lymph node investigation was done by Hematoxylin-Eosin staining. Results: On lymphoscintigraphy, three of 15 patients had clear lymphatic vessels in dynamic images, and 11 of 15 patients showed sentinel lymph node in early static image and three in late static 2 hours image. Mean detection time of sentinel lymph node on lymphoscintigraphy was $33.5{\pm}48.4$ minutes. The sentinel lymph node localization and removal by lymphoscintigraphy and intraoperative gamma probe were successful in 14 of 15 patients (detection rate: 93.3%). On lymphoscintigraphy, 14 of 15 patients showed $2.47{\pm}2.00$ sentinel lymph nodes. On intraoperative gamma probe, $2.36{\pm}1.96$ sentinel lymph nodes were detected. In 7 patients with positive results of sentinel lymph node metastasis, 5 patients showed positive results of axillary lymph node (sensitivity: 72%) but two did not. In 7 patients with negative results of sentinel lymph node metastasis, all axillary nodes were free of disease (specificity: 100%). Conclusion: Sentinel lymph node biopsy with lymphoscintigraphy and intraoperative gamma probe is a reliable method to predict axillary lymph node metastasis in breast cancer, and unnecessary axillary lymph node dissection can be avoided.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.2
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• pp.289-295
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• 2001

The aim of this study is to investigate the ductile fracture behaviour under pure Mode II loading using A533B pressure vessel steel. Single punch shear(SPS) test was performed to obtain the J-R curve under pure Mode II loading which was compared with that of the Model I loading. Simulation using Rousellier Ductile Damage Theory(RDDT) was carried out with 4-node quadrilateral element(L(sub)c=0.25mm). For the crack advance, the failed element removal technique was adopted with a $\beta$ criterion. Through the $\beta$ value tuning-up procedures, $\beta$(sub)crit(sup)II was determined as 1.5 in contrast with $\beta$(sub)crit(sup)I=5.5. In conclusion, it was found that the J-R curve under Mode II loading was located at lower part than that under Mode I loading obtained from the previous study and that the $\beta$ values strongly depended on the loading type. In addition, the predicted result using RDDT showed a good agreement with the SPS experimental one under pure Mode II loading.

• The Journal of Internal Korean Medicine
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• v.34 no.3
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• pp.322-328
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• 2013

Objectives : The purpose of this study was to report two cases which suggest Oryeongsan as a pharmacological treatement option for cancer-induced secondary lymphedema. Methods : The cases were two female patients with peripheral edema. The first was diagnosed with cervical cancer with paraaortic lymph node metastasis and suffered from bilateral edema of the lower extremities. The second was a breast cancer patient with right arm lymphedema, which was aggravated after a weekly regimen of chemotherapy. Oryeongsan was orally administered for 3-4 days to both patients. Results : The symptoms in lower extremities and body weight of the cervical cancer patient decreased. The breast cancer patient did not lose body weight, but pain in upper extremities was reduced. Conclusions : Oryeongsan may potentially be an option for secondary lymphedemas, including cancer-induced lymphedema.