• Korean Journal of Optics and Photonics
• /
• v.8 no.4
• /
• pp.267-276
• /
• 1997

We set up a four-wave holographic interferometer using a symmetric dual-beam illumination which is to measure in-plane and out-of-plane displacement simultaneously. In order to acquire the displacement phase map we applied the phase-shifting method and removed the noise of the phase map with least-squares fitting. In this approach the access to information relative to both the difference and sum of phases existing in the two arms of four-wave holographic interferometer was allowed. As a result, in-plane and out-of-plane displacement was measured to the accuracy of λ/40 and λ/100, respectively at λ=632.8nm

• Knowledge Management Research
• /
• v.10 no.2
• /
• pp.35-48
• /
• 2009

The paper proposes a quantitative causal ordering map (QCOM) to combine qualitative and quantitative methods in a framework. The procedures for developing QCOM consist of three phases. The first phase is to collect partially known causal dependencies from experts and to convert them into relations and causal nodes of a model graph. The second phase is to find the global causal structure by tracing causality among relation and causal nodes and to represent it in causal ordering graph with signed coefficient. Causal ordering graph is converted into QCOM by assigning regression coefficient estimated from path analysis in the third phase. Experiments with the prediction model of Korea stock price show results as following; First, the QCOM can support the design of qualitative and quantitative model by finding the global causal structure from partially known causal dependencies. Second, the QCOM can be used as an integration tool of qualitative and quantitative model to offerhigher explanatory capability and quantitative measurability. The QCOM with static and dynamic analysis is applied to investigate the changes in factors involved in the model at present as well discrete times in the future.

• Journal of Powder Materials
• /
• v.6 no.1
• /
• pp.81-87
• /
• 1999

Based on the pore filling theory, the microstructure evolution during liquid-phase sintering has been analyzed in terms of interrelationship between average grain size and relative density. For constant liquid volume fraction, the microsturucture trajectories reduced to a single curve in a grain size(x)-density(y) map, regardless of grain growth constant. The slope of curves in the map was inversely proportional to average pore size, while it increased fapidly with liquid volume fraction. Increase in pore volume fraction retarded the densification considerably, but showed marginal effect on the slope. The activation energy of densification was predicted to be the same as that of grain growth as long as the liquid volume fraction is constant for any temperature range studied. The present analyses on microstricture evolution may demonstrate the usefulness of pore filling theory and provide a guideline for process optimization of liquid-phase sintering.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.24 no.4
• /
• pp.31-46
• /
• 2021

In South Korea, there is a growing domestic need for a biotope map which contains ecological and environmental geographic information of a city. After the production of a Urban Ecological Maps(biotope map) by the Seoul metropolitan government in 2000, Natural Environment Conservation Act was revised in 2017 to make it mandatory for a local government to draw up its own urban ecological map. The aim of the present study was to find out ways to utilize an urban ecological map as a mean of communication between natural environment planning and urban planning sectors in a preliminary stage before introducing a big framework of 'environmental and ecological planning.' The northern area of Incheon metropolitan city was selected as the target area for this study. The major research content includes a comparative analysis of special-purpose zones, urban planning zones, restricted development zones, and conservation forests with focus on biotope types and Grades 1 of 'Biotope Type Assessment.' Farmland biotopes and forest biotopes within an area designated as an urban zone (residential, commercial and industrial zones) need to be redesignated as a zone which can conserve them. Especially considering a high possibility of damage to a large scale of natural green areas, these areas need to be readjusted immediately. If the entire area designated as an urban planning zone is to be developed, it is likely to cause serious damage to natural biotopes in the area (56.2%), including farmland biotope (30.4%), forest biotope (15.0%) and grassland biotope (10.8%), and thus, readjustment is needed. In case of a conservation forest, as it can possibly be damaged by the designation of special-purpose zones, it is necessary to match the designation of conservation forests or a special-purpose zones with their biotope types. In conclusion, we present a variety of thematic maps for utilization of an urban ecological map and propose a phase-specific environmental and ecological plan. Phase 1 is the establishment of a urban plan in consideration of ecological status; Phase 2 is the independent establishment of an environmental and ecological plan by an environment department; Phase 3 is an integrated management of ecological planning system and urban planning system.

• BMB Reports
• /
• v.32 no.4
• /
• pp.379-384
• /
• 1999

Taxol, a natural product with significant anti-tumor activity, stabilizes microtubules and arrests cells in the G2/M phase of the cell cycle. It has been reported that taxol has additional effects on the cell such as an increase in tyrosine phosphorylation of proteins and activation of mitogen-activated protein (MAP) kinase. This phosphorylated kinase translocates into the nucleus and phosphorylates its substrate c-jun, c-fos, ATF2, and ATF3. The MAP kinase family is comprised of key regulatory proteins that control the cellular response to both proliferation and stress signals. First examination was cytotoxicity and apoptosis-induced concentration with paclitaxel in HeLa cell. A half-maximal inhibition of cell proliferation ($IC_{50}$) occurred at 13 nM paclitaxel. When DNA fragmentation was analyzed by agarose gel electrophoresis, a nucleosomal ladder became evident 24 h after a taxol (50 nM) addition to the cells. In addition, an apoptotic body was detected by electron microscopy. Taxol-treated cells were arrested at the S phase at 10 nM. Treatment of 50 nM taxol activated the extracellular signal-regulated protein kinase (ERK1), and a fraction of the activated MAP kinases entered the nucleus. It was also discovered that nucleus substrates c-jun was phosphorylated and activated in the cell. The activated ERK1 could subsequently translocate into the nucleus and phosphorylate its substrate c-jun as well. This study suggests that taxol-induced apoptosis might be related with signal transduction via MAP kinases.

• Toxicological Research
• /
• v.17
• /
• pp.251-256
• /
• 2001

The expression of phase II detoxifying enzymes is affected by a variety of compounds and the induction of the enzymes plays an essential role in chemoprevention. A variety of phytochemicals such as sulfur-containing chemoprotective agents (SCC) may trigger cellular signals and activate phase II gene expression through ARE activation. see induces glutathione S-transferases. Studies were conducted to investigate the role of mitogen-activated protein (MAP) kinase and phosphatidylinositol 3-kinase (PI3-kinase) in the induction of GST (e.g. rGSTA2) by sec. We also studied the MAP kinase pathway responsible for the GST expression by see and compared that with the pathway activated by oxidative stress as a result of sulfur amino acids deprivation (SAAD). see inhibited phosphorylation of ERK1/2 although the effect of see on JNK and p38 MAP kinase was minimal. Wortmannin and LY294002. PI3-kinase inhibitors. abolished the increases in rGSTA2 mRNA and protein levels by SCC. Deprivation of cystine and methionine caused oxidative stress in H4IIE cells. as evidenced by a decrease in the reduced glutathione and an increase in prooxidant production. Electrophoretic mobility shift assay revealed that the ARE complex consisting of Nrf-1/2 and Maf proteins was activated 12~48 h. The rGSTA2 mRNA and protein levels were increased by SAAD. Activation of ARE and induction of rGSTA2 were both completely inhibited by PI3-kinase inhibitors. Inhibition of p38 MAP kinase by SB203580 prevented the ARE-mediated rGSTA2 induction. The results of this study showed that PI3-kinase might play an essential role in the ARE-mediated rGSTA2 induction by see or SAAD and that the dual MAP kinase pathways were responsible for the enzyme induction.

• Journal of Information Processing Systems
• /
• v.12 no.3
• /
• pp.538-547
• /
• 2016

Cloud computing is a new style of computing in which dynamically scalable and reconfigurable resources are provided as a service over the internet. The MapReduce framework is currently the most dominant programming model in cloud computing. It is necessary to protect the integrity of MapReduce data processing services. Malicious workers, who can be divided into collusive workers and non-collusive workers, try to generate bad results in order to attack the cloud computing. So, figuring out how to efficiently detect the malicious workers has been very important, as existing solutions are not effective enough in defeating malicious behavior. In this paper, we propose a security protection framework to detect the malicious workers and ensure computation integrity in the map phase of MapReduce. Our simulation results show that our proposed security protection framework can efficiently detect both collusive and non-collusive workers and guarantee high computation accuracy.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.9
• /
• pp.2099-2104
• /
• 2010

In this paper, HRV signal which was appeared RR intervals from ECG was analyzed using return-map during anesthesia. We intended to estimate the depth of anesthesia observing the change of autonomic nervous activity(ANS) because HRV showed change of cardio-vascular system of the body according to state of ANS. Return-map analysis is to reconstruct time series of HRV to phase space after calculating delay time and embedded time. After approximating the signal distribution which was reconstructed in phase space in elliptic, we calculated the lengths of major and minor axises of the elliptic and the values was used to estimate the depth of anesthesia. Stages of the anesthesia were 7 levels to evaluate the depth of anesthesia. At induction stage of strong external stimulation, the length of major and minor axis were statistically high and at the operation stage of non-external stimulation, the values were statistically low. Conclusively, the stages of anesthesia were discriminated by HRV signal mapped in the phase space during operation.

• KIISE Transactions on Computing Practices
• /
• v.23 no.2
• /
• pp.110-115
• /
• 2017

We propose a new indoor positioning algorithm named Cut-off algorithm. This algorithm cuts off candidates of beacons and reference points in advance, before looking for K neighbor reference points which are guessed to be closest to the user's actual location. The algorithm consists of two phases: off-line phase, and on-line phase. In the off-line phase, RSSI and UUID data from beacons are gathered at reference points placed in the indoor environment, and construct a fingerprint map of the data. In the on-line phase, the map is reduced to a smaller one according to the RSSI data of beacons received from the user's device. The nearest K reference points are selected using the reduced map, which are used for estimating user's location. In both phases, relative ranks of the peak signals received from each beacon are used, which smoothen the fluctuations of the signals. The algorithm is shown to be more efficient in terms of accuracy and estimating time.

• Journal of Advanced Navigation Technology
• /
• v.26 no.1
• /
• pp.22-28
• /
• 2022

In order to install ultra wide band and ultra long-haul transmission link based on standard single mode fiber, optical signal distortion due to chromatic dispersion and nonlinear Kerr effect must to be compensated. In this paper, optical link consisted of dispersion management and optical phase conjugation is proposed for compensation of the distorted wavelength division multiplexed (WDM) channels. Dispersion map profile in the proposed dispersion-managed link is configured by periodic repetitive shape, and optical phase conjugator is placed at various position including the midway of total transmission length. It is confirmed from simulation results that when the residual dispersion per span (RDPS) selected in the proposed dispersion-managed link to be large, the compensation of distorted WDM channels in the non-midway OPC system is more improved than the conventional dispersion-managed link.