• Membrane Journal
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• v.8 no.4
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• pp.203-209
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• 1998

The cutting oil emulsion microfiltration was carried out on dead-end call and crossflow systems equipped with 0.22 $\mu$m GVHP Millipore and 0.2 m stainless steel Mott microfiltration membranes, respectivdy. The oil drop size in the emulsion was varied from 0.07 to 0.22 $\mu$m. Cake filtration(CFM) and standard pore blocking models(SPBM) were applied to predict the permeation flux. The permeation fluxes of 0.01 vol% oil emulsion followed CFM for dead-end system very well under the condition of 400 rpm and below 100 kPa. The SPBM was, however, suitable for the permeation flux at 400 rpm and above 150 kPa. The oil layer on the membrane surface was destroyed and reproduced repeatedly as operating pressure was suddenly changed from 60 to 200 kPa, and then returned to 60 kPa. Also, we estimated the critical entry pressure(CEP) which is changed from CFM to SPBM, and CEP for dead-end system was around 100 kPa. The CEP increased from around 100 to 150 kPa for the crossflow system as the oil concentration increased from 0.01 to 0.03 vol% when Reynolds number was 7080.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.113-120
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• 2006

This thesis deals with solutions such as coverage area extension, reduction of the shadow region and performance enhancement of handover caused by structural modification of WiBro network. The More far the distance of RAS(Radio Access Station) and SS(Subscriber Station) is in micro cell, the more bad the quality of channel environment becomes owing to radio interference. Consequently, it causes the deterioration of the throughput and also the deterioration of communication quality in many sides. In fact, most users of WiBro are located in the region, the QPSK region which is bad in point of channel quality. It brings the service complaint by user. We select RS(relay station) to solve the matter caused by channel environment in this cell, and extend coverage and improve the performance of handover call blocking.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.2
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• pp.17-23
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• 2000

Wireless link has high bit error rate compared with wired link and many users share this limited bandwidth. So it needs more powerful error control code and efficient media access control(MAC) to provide multimedia service reliably. In this paper we proposed efficient MAC frame format based on TDMA using mini-slot for request access. The number of mini-slots is variable based on the result of collision in the previous frame. This dynamic allocation of request mini-slots helps resolve the contention situation quickly and avoids the waste of bandwidth that may occur when there are several unneeded request mini-slots. The simulation results are also presented in terms of channel utilization, call blocking probability and cell transmission delay for mixed traffic environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8A
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• pp.1195-1207
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• 1999

Wireless channel has high error rate and limited bandwidth. In order to guarantee the quality of service for multimedia through wireless channel, wireless ATM network requires the cell structure with error control schemes and an efficient medium access control protocol. In this paprt, an efficient medium access control protocol, which is considered of cell structure and the QOS, is proposed for wireless ATM networks. Many kinds of ATM cell structures are analyzed in terms of cell error rate and cell loss rate to choose the proper cell structures for this proposed MAC protocol. And a bandwidth allocation algorithm is also designed to satisfy the priority of services. The performance of proposed MAC protocol are evaluated in terms of channel utilization, call blocking and packet discard probability accotding to different kinds of cell structure through simulation.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5937-5946
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• 2012

The term endocrine disruptors is used to describe a variety of natural and manmade substances that have the capacity to potentially interfere with and modify the normal physiology of endocrine system either by mimicking, blocking or modulating the actions of natural endogenous hormones. The rising incidence of breast cancer over the last 50 years and the documented higher incidence in urban as compared to rural areas suggest a relationship to the introduction and increased use of xenoestrogens in our environment. The literature has developed over the last decades where initial experiments on endocrine disruptors did not support an involvement in breast cancer, and then evidence mounted implicating various environmental factors including hormones, endocrine disrupting chemicals and non-endocrine disrupting environmental carcinogens in the pathogenesis of breast cancer. Available data support the hypothesis that exposure to endocrine disruptors in utero leaves a signature on mammary gland morphogenesis so that the resulting dysgenic gland becomes more predisposed to develop tumors upon exposures to additional insults later on during life. Exceptionally, exposure to phytoestrogens could be beneficial to human health. Most of the available data are from well developed countries while the developing countries are still understudied regarding these issues. Here, we raise a note of caution about potential role of environmental toxins including endocrine disruptors in breast cancer development and call for serious measures to be taken by all involved parties in the developing world.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.6 s.324
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• pp.69-78
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• 2004

This paper proposes architecture and characteristics of a multi-ring based optical network with single-hop between edge nodes using the concept of circuit switching and multi-wavelength label switching to solve delay problem caused by applying crossconnectors as transit nodes in the wavelength division multiplexing(WDM) network. We suggest multi-ring based architecture composed single and multiple wavelength-bands with multi-wavelength labels, and analyze characteristics of two models. To avoid the packet collision in output ports of edge nodes due to output contention, the static and dynamic allocation scheme, which packets are allocated in time slots, is provided. Based on our analysis, it shows that delay only occur in not core nodes but edge nodes in the proposed architecture. In addition, we evaluate the probabilities of delay, packet loss, and call blocking in the proposed optical packet network.

• Journal of Korea Multimedia Society
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• v.6 no.6
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• pp.1100-1110
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• 2003

Design and implementation of remote procedure cail (RPC) resource service system based on the XML considering the request delegation between the servers are described for the resource application and efficient processing of distributed environment. For this purpose, the request information about several server, which would be used by client, is encoded into XML document based on XML-DOM and transferred to server. Server classifies the client requests using objects which can deal with the XMLL-DOM. For the request delegation between the servers, server saves the request result of client in XMLL-DOM structure without replying it immediately, and makes the client request delegated to another server in XML-DOM's request information. In addition, the resource repository are managed for resource transparency of distributed environment. As a result, resource application and processing efficiency are improved by reduction of response time caused by integration of RPC and XML-RPC services and request delegation between the servers. Extension of asynchronous and average blocking time of client were reduced and information of resource which can be used by client was offered.

• Korean Journal of Oriental Medicine
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• v.2 no.1
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• pp.514-550
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• 1996

There are many theory in acupuncture mechanism, so we must know the detail contents. and then we can use the acupuncture as we know. the follow article will be helpful in this part. 1. Spinal cord are role in intermediate part in somatosensorypathway also in acupuncture stumulating tract 2. Acute pain pathway started in laminae I, V of gray colmn, next are the spinothalamic tract(trigeminal spinothalamic tract in above neck part) and then go to the specific thalamic nucleus. but chronic pain in laminae II, III, VI, VII, next are spinoreticular tract(trigeminal spinoreticular tract in the neck part) and finally to the nonspecific thalamic nucleus. 3. Thalamus is very important area in somatosensory stimuation including acupuncture stumulating sensory also as a pain control center. but except this, there are Hypothalamus, Limbic system Cerebral cortex and Cerebellum as intermediator. as we Know hypothalamus is related to the emotional analgesic system with a limbic system. 4. A ${\delta$ fiber has relationship in Acute, sharp and initial pain, contrary this C fiber is related with Chronic, dull and last pain. 5. In Acupuncture mechanism of pain analgesia, there are two theory, one is gate control theory as large fiber another is stimuation produced analgesia as small diameter fier. 6. In DNIC, the stimulation sources are mechanical, thermal, heating, pain and acupuncture stimulation etc. we call these as a Heterotopic Noxious Stimulation. 7. In DNIC, SRD(Subnucleus reticularis dorsalis)is core nucleus in pain imtermediated analgesic mechanism. 8. Takeshige insisted nonacupuncture point dependent analgesic mechanism and acupuncture point dependent analgesic mechanism. and protested that Stimulation acupuncture piing evoke blocking nomacupuncture point analgesic pathway.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4A
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• pp.394-400
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• 2010

Mobile Multi-hop Relaying (MMR) system can provide increased system capacity of wireless access network by coverage extension and enhanced transmission rate within the Base Station (BS) coverage area. The previous researches for the MMR system with a non-transparent mode Relay Station (RS) do not consider channel selection procedure of Mobile Station (MS), co-channel interference and Multi-hop Relay Base Station (MR-BS) coverage and RS coverage ratio in MMR system. In this paper, we investigate the performance of MMR uplink system in multicell environments with various topologies. The performance is presented in terms of call blocking probability, channel utilization, outage probability and system throughput by varying offered load. It is found that, for certain system parameters, the MMR uplink system achieve the maximum system throughput when MR-BS coverage to RS coverage ratio is 7.

• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.1058-1070
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• 1999

In this paper, we propose a control model which can control the burst input messages of the BSC(Base Station controller) in mobile communication systems more efficiently and reliably, by dividing the input messages characteristically and using multiprocessor system. Using M/M/c/K queueing model, we briefly analyze proposed model to get characteristic parameters which are required to performance improvement. On the base of the results, we compare our proposed model with the conventional one by using SLAM II with regard to the following factors : the call blocking rate of the input message, the distribution of average queue length, the utilization of process controller(server), and the distribution of average waiting time in queue. In addition, we modified our model which has overload control function for burst input messages, and analyzed its performance.