• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.829-832
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• 1999

KORTASAT-III is planning to provide Ka-band broadband communication service, including eastsouth Asia area. In this paper, we calculate the link budget for Ka-band KOREASAT-III multimedia service and describe the performance of multimedia services according to link design parameters. There are Trunk service, Television receive only service, Two-way point-to-multipoint service, Tele-education service in the service scenario.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.640-643
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• 2002

본 연구에서는 위성통신을 이용한 방송 및 멀티미디어 서비스의 확대를 앞두고 20[GHz] 이상의 높은 주파수 대역의 강우에 의한 전파 손실 예측 모델을 제안하고 강우량에 따른 감쇠 정도를 기존의 모델과 비교 분석하였다. 특히 위성 방송대역으로 이용될 Ka 대역에서 강우 감쇠에 의한 전파 손실을 제시하고 Ka 대역 위성통신 링크 설계를 위한 기본 자료를 제공하고 강우 감쇠 극복 대책을 제시하고자 한다.

• Food Science and Preservation
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• v.5 no.2
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• pp.150-153
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• 1998

As strait As a result of the quality research of liner boards used for the national-made corrugated boxes for apples, basis weight of each sample passed its tolerance within 4%. We found that KA, WLK, and SC liner boards showed better in relative bursting strength. SC, WLK, KA, and SK performed better in relative compression strength. WLK201 and KA210 were good for the outside liner, and K2200 was adequate for medium and inside liner. we classified WLK and KA liner boards as A grade and others as C grade.

• Korean Linguistics
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• v.62
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• pp.171-194
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• 2014

In this paper, I seek to differentiate the meaning of the auxiliary verb '-e ka-' from imperfective aspect in Korean. The progressive in imperfective is expressed by the 'be+V-ing' in English and '-ko iss-' in Korean. However the '-e ka-' in Korean can express the gradual progress meaning. This is similar to the progressive of some state verbs. These verbs cannot express the progressive aspect but it is possible if they can express the change of state in sentence. It is more corresponding to the '-e ka-' than '-ko iss-' in Korean.

• Korean Journal of Acupuncture
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• v.29 no.3
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• pp.396-405
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• 2012

Objectives : To confirm whether acupuncture can suppress the degree of seizure and the activation of astrocytes in hippocampi using kainic acid(KA)-induced epilepsy mouse model. Methods : 8 weeks C57BL/6 mice(20~25 g) were given acupuncture once a day at acupoint HT8(Shaofu) bilaterally during 2 days before KA injection. After an intraperitoneal injection of 30 mg/kg KA, acupuncture treatment was subsequently administered once more(total 3 times), and the degree of seizure was observed for 120 min. The neuronal cell death, pERK expression, and astrocyte activation confirmed 1 hour and 24 hours after KA injection. Results : Acupuncture treatment at HT8 suppressed KA-induced epileptic seizure. One hour after KA injection, the pERK expression was increased, which was reduced by the acupuncture treatment. Twenty four hours after injection, the treatment decreased the KA-induced neuronal cell death, the interleukin-$1{\beta}$ expression and the astrocyte activation in the CA3 region of the mouse hippocampus. Conclusions : Acupuncture treatment at HT8 decreases the KA-induced epileptic seizure, the neural cell inflammation and death.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.268-273
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• 1999

To measure the precision of Soiltek$^{(R)}$ KA-1 spectrophotometric measurement of soil available phosphate, standard deviation, C;V, and relative sensitivity were investigated, comparing to Lancaster method. Available phosphate concentration measured by Soiltek$^{(R)}$ KA-1 spectrophotometric method was highly correlated with Lancaster method($r=0.998^{***}$) and the slop of regression equation was close to 1.0. There were no differences in standard deviation. CV, and relative sensitivity for soil available phosphate concentrations measured by two methods. Regarding to convenience of experimental procedure and instrumental operation, and time saving analysis, Soiltek$^{(R)}$ KA-1 spectrophotometric measurement for soil available phosphate is highly recommended.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.291-297
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• 2014

The radioprotective effects of a single administration of kojic acid (KA) against ionizing radiation were evaluated via assessment of 30-day survival and alterations of peripheral blood parameters of adult C57BL/6 male mice. The 30-day survival rate of mice pretreated with KA (75 or 300 mg/kg body weight, KA75 or KA300) subcutaneously 27 h prior to a lethal dose (8 Gy, 153.52 cGy/min) of gamma irradiation was higher than that of mice irradiated alone (40% or 60% vs 0%). It was observed that the white blood cell (WBC) count/the red blood cell (RBC) count, haemoglobin content, haematocrit and platelet count of mice with or without KA pretreatment as exposed to a sub-lethal dose (4 Gy, 148.14 cGy/min) of gamma irradiation decreased maximally at day 4/day 8 post-irradiation. Although the initial WBC values were low in KA300 or WR-2721 (amifostine) groups, they significantly recovered to normal at day 19, whereas in the control group they did not. The results from the cytotoxicity and cell viability assays demonstrated that KA could highly protect Chinese hamster ovary (CHO) cells against ionizing radiation with low toxicity. In summary, KA provides marked radioprotective effects both in vivo and in vitro.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.6
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• pp.375-379
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• 2003

$Ca^{2+}$ influx appears to be important for triggering myoblast fusion. It remains, however, unclear how $Ca^{2+}$ influx rises prior to myoblast fusion. Recently, several studies suggested that NMDA receptors may be involved in $Ca^{2+}$ mobilization of muscle, and that $Ca^{2+}$ influx is mediated by NMDA receptors in C2C12 myoblasts. Here, we report that other types of ionotropic glutamate receptors, non-NMDA receptors (AMPA and KA receptors), are also involved in $Ca^{2+}$ influx in myoblasts. To explore which subtypes of non-NMDA receptors are expressed in C2C12 myogenic cells, RT-PCR was performed, and the results revealed that KA receptor subunits were expressed in both myoblasts and myotubes. However, AMPA receptor was not detected in myoblasts but expressed in myotubes. Using a $Ca^{2+}$ imaging system, $Ca^{2+}$ influx mediated by these receptors was directly measured in a single myoblast cell. Intracellular $Ca^{2+}$ level was increased by KA, but not by AMPA. These results were consistent with RT-PCR data. In addition, KA-induced intracellular $Ca^{2+}$ increase was completely suppressed by treatment of nifedifine, a L-type $Ca^{2+}$ channel blocker. Furthermore, KA stimulated myoblast fusion in a dose-dependent manner. CNQX inhibited not only KA-induced myoblast fusion but also spontaneous myoblast fusion. Therefore, these results suggest that KA receptors are involved in intracellular $Ca^{2+}$ increase in myoblasts and then may play an important role in myoblast fusion.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.114-114
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• 2014

We present our activities linking to planning of possible forms of large program to study on circumstellar H2O and SiO maser sources with KaVA. A great advantage of KaVA for the stellar maser observations is the combination of the unique capability of the multi-frequency phase referencing technique of KVN and the dual-beam astrometry of VERA with the KaVA's relative dense antenna configuration. We have demonstrated this advantage through the test observations conducted by the KaVA Evolved Stars Sub-working Group since 2012 March. Snapshot KaVA imaging is confirmed to be possible in integration time of 0.5 hour at the 22 GHz band and 1.0 hour at the 43 GHz band in typical cases. This implies that large snapshot imaging surveys towards many H2O and SiO stellar masers are possible within a reasonable machine time (e.g., scans on ~100 maser sources within 200 hours). This possibility enables us to select the maser sources, which are suitable for future long-term (10 years) intensive (biweekly-monthly) monitoring observations, from 1000 potential target candidates selected from dual-frequency band (K/Q-bands) KVN single-dish observations. The output of the survey programs will be used for statistical analysis of the structures of individual stellar maser clumps and the spatio-kinematical structures of circumstellar envelopes with accelerating outflows. The combination of astrometry in milliarcsecond(mas) level and the multi-phase referencing technique yields not only trigonometric parallax distances to the masers but also precise position reference for registration of different maser lines. The accuracy of the map registration affects interpretation of the excitation mechanism of the SiO maser lines and the origin of the variety of the maser actions, which are expected to reflect periodic behaviors of the circumstellar envelope with stellar pulsation. Currently we are checking the technical feasibility of KaVA operations for this combination. After this feasibility test, the long-term monitoring campaign program will run as one of KaVA's legacy projects.

• Korean Journal of Acupuncture
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• v.23 no.2
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• pp.19-27
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• 2006

Objectives: Although Korean Acupuncture (KA) in Korean Medicine (KM) shares its origins with Traditional Chinese Medicine (TCM), it has made its own contribution to the field of acupuncture and general medicine. This study reviews characteristics of KA. Methods: Representative theories of KA were reviewed in light of a constitutionally individualized and practically integrated approach. Individualized approach in KA is based on constitutional energy traits recognized in Saam, Taegeuk, and Eight Constitution acupuncture theories. New practically integrated therapeutic modalities, such as herbal, and bee venom acupunctures, have also been developed in KA. Results: As a form of natural medicine, KA along with KM put emphasis on the vitality and self-correcting mechanism of an individual, which led to the refinement of constitutional approach. KA along with KM theories features a summarized understanding and practical application of integrated therapeutics, which produced creative development of new modalities. Conclusions: KA is expected to make significant contributions to the individualized and practical medicine, based on basic research and clinical trials.