• Journal of the Korean Ceramic Society
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• v.52 no.1
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• pp.33-40
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• 2015

Onggi, described as a 'breathing' type of pottery' has significantly influenced the traditional food culture of Korea. It is known that Onggi is an optimal type of storage for fermented foods such as soy sauce, salted seafood, and Kimchi, as air or liquid can penetrate through the body of this material. These foods gain flavor due to the breeding of aerobic bacteria at the beginning of the fermentation process. In this study, Onggi materials from five regions, Gangjin, Yeoju, Ulsan, Yesan, and Jeju, were collected and analyzed to determine their chemical and physical properties before and after sintering. The differences in the raw materials of other mining regions are examined in terms of their chemical and mineralogical compositions, specific surface area, particle size, and particle distribution. Among them, the Gangjin raw material has the greatest mean particle size of $92.29{\mu}m$, as well as the widest particle size distribution. Differences in the levels of $SiO_2$ and $Fe_2O_3$ are shown among Onggi raw materials. However, the crystalline phases formed after sintering are identical, except for the Jeju samples. At all sintering temperatures tested here, Gangjin Onggi showed the greatest porosity, leading to complete air permeation through the body within 90 minutes. These results taken together indicate that air permeation is strongly related to the pore structures in the Onggi body. This is assumed to affect the fermentation behavior.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.1822-1831
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• 2014

Micro-grid is connected to the main power grid through a static switch. One of the critical issues in micro-grids is protection which must disconnect the micro-grid from the network in short-circuit contingencies. Protective methods of micro-grid mainly follow the model of distribution system protection. This protection scheme suffers from improper operation due to the presence of single-phase loads, imbalance of three-phase loads and occurrence of power swings in micro-grid. In this paper, a new method which prevents from improper performance of static micro-grid protection is proposed. This method works based on artificial neural network (ANN) and able to differentiate short circuit from power swings by measuring impedance and the rate of impedance variations in PCC bus. This new technique provides a protective system with higher reliability.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2228-2229
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• 2008

한국전력공사에서는 신배전정보시스템(NDIS1)) 및 배전자동화(DAS2)) 활용능력 향상과 배전업무 우수인력 양성을 위하여 2004년부터 매년 배전기술경진대회를 치러오고 있으며 올해 제5회 대회를 맞이하고 있다. 따라서 2004년부터 현재까지 배전기술 경진대회의 발전 방향을 소개하고, 아울러 대회 신청자, 참가자 등 각종 데이터에 대한 이력관리를 통하여 결과를 분석하고 참가자에 대한 업무수행 능력 수준 및 평가요소별 강 약점을 제시하고 지역별, 연령별 수준분석을 통한 배전정책결정 기초 자료로 활용하고자 한다.

• Journal of The Korean Astronomical Society
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• v.27 no.2
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• pp.119-132
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• 1994

The BVR CCD photometry was performed for the globular cluster M13 down to $V=19^m$ over the region from the center to the west 13 arcmin and the CMD of M13 is investigated. The major photometric error in the crowded field which is due to the variation in the sky background was corrected by the median filtering method and the direct sky method. Some characteristics of the CMD of M13 obtained in the present study are as follows: Firstly, the distribution of stars on the CMD is well consistent with the mean lines of Sandage(1970) along the red giant branch(RGB), horizontal branch(HB) and asymtotic giant branch(AGB). Secondly, some gaps exists along the RGB and blue horizontal branch(BHB). Thirdly, the UV-bright stars are more concentrated at the inner region of the cluster.

• Ocean and Polar Research
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• v.23 no.4
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• pp.323-335
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• 2001

Distribution features of foulers attached on 28 ships of 6 main shipping routes (SR) of the Far East Sea Basin were analyzed using various statistical methods. Collections obtained during 1976-1990 in the expeditions by the Institute of Marine Biology were used for the analyses. Samples were taken from the ships during anchorage by SCUBA diving and from dry-docks of Vladivostok ship-repairing yard. In all cases, the distribution patterns of most animals and algal species showed clear contagious patterns. Total biomass of fouling organisms and biomass of attached animals frequently increased along the horizontal direction of ship hulls, from the stem to the sternpost. Animal and algal species were usually located at different sites of the hulls. According to the increasing floating speed, there was, a clear tendency of the displacement in main fouling biomass from the stem to the stem. Any generalizations and deductions concerning the distribution patterns of the foulers from the same SR ships are not always substantiated, but one may see some similarities of the fouler distributions in many cases. Micro-scale turbulence generated by water flow around a ship hull for the distribution of fouling organisms is discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.8
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• pp.1136-1145
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• 1993

The channel capacities of various lading channels are calculated and compared with that of Gaussian noise channel to find out the decrements of channel capacity according to each fading environment. As a result, it is confirmed that the channel capacities in Rician and m-distribution fading channels approach to that of Gaussian noise channel as direct-to-indirect power ratio in Rician fading channel and fading index m in m-distribution fading channel increases respectively. And the difference between two channel capacities of Gaussian noise channel and each fading channel which is dependent on carrier-to-noise power ratio (CNR) is found. Also the improvement of channel capacity of Rayleigh fading channel by introducing two-branch diversities is obtained. For diversity reception, predetection maximal-ratio and postdetection selective combining techniques are adopted. The results show that the improvement of channel capacity by predetection maximal-ratio combining diversity is superior to the postdetection selective combining diversitiy regardless of correlation coefficient between two diversity branches in Raylelgh fading channel. The best improvement is achieved when two branches are noncorrelative in both two diversify techniques and as correlation coefficient of two diversity branches is smaller, the improvement of channel capacity is greater.

• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.119-124
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• 2009

The epidemiological survey of mass outbreak region of bovine tuberculosis from January of 2007 through May in 2009. The results were enumerated as follows. The results of tuberculin skin test are: 7 (0.4%) out of 1,697 in 2007, 61 (2.8%) out of 2,163 in 2008, 80 (4.9%) out of 1,639 in 2009. The sex and age distribution among the incidence of positive: 135 (91.8%) out of 147 in female, 12 (8.2%) in male. Among female, age 1: 6.1%, age 2: 30.6%, 3: 38.8%, 4: 14.2%, 5: 0.7% and 6: 1.4%. Among male, age 1: 4.1%, 2: 1.4%, 3: 2.7% and more frequent occurrence in age 3, 38.8% in female and 2.7% in male. The rate of recurrence by farms: recurrence 1: 6 (35.3%), 2: 9 (52.9%), 3: 1 (5.9%), 6: 1 (5.9%), The recurrence rate of 2 or more was 64.7%. The ELISA test result among 114 heads over 14 farms: 75 (65.8%) showed positive and 39 (34.2%) negative. Geographical distribution of recurrence is characterized as concentrated along the major traffic and stream crossing the village, and spread from the high elevation to downward area.

• Journal of Plant Biology
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• v.17 no.3
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• pp.118-126
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• 1974

Mulberry plants cultivated in mid-Korea were studied on the growth habitat, canopy type, productive structure and vertical light intensity in relation to the quality of mulberry leaves for sericulture. The growth in length of new branch of summer cut mulberry in spring was vigorous on the uppermost of old shoot. Numbers of leaves on a branch were barely 4 leaves on lower than 20th branch from base, but those were 13 leaves on higher than 24th branch. Area of leaves completely expanded was broad on high branch, but narrow on low one. The form of canopy, the type of productive structure and the vertical light distribution depend upon varieties of cultivated mulberry plants were classified according to characteristic of each variety in two groups, respectively; globular and columnar form in canopy, broad leaves and narrow leaves types in productive structure, and seriously obstructured the light and fairly transmitted the light into lower leaf stratum invertical light distribution. Out of varieties of mulberry investigated, Suwon No. 4 and Rosang were belong to the former characters, but Illchiroe and Kaeryangsubun were to the latters. The values of leaf dry matter index and dry matter production produced by leaves were increased in direct proportion to the height of leaf stratum; the leaf dry matter index of the uppermost leaf was twice as much that of the lowest, and the dry matter production by the highest leaf was 17 times compared with that by the lowest leaf. It is assumed that the meagre leaves occurred in the lower leaf stratum of Suwon No. 4 and Rosang were caused to diminished the dry matter index and dry matter production in the under leaves of plant, which were affected by receiving the weak light.

• Proceedings of the KIEE Conference
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• summer
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• pp.199-201
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• 2004

KEPCO, has been made a lot of efforts for computerization for distribution planning system since 1980's, And as a results, DISPLAN (Distribution PLANning System) for systematic and effective planning was developed in 2003 and is being used for feeder and substation planning of KEPCO branch office. In this paper the distribution load forecasting algorithm in DISPLAN is represented and the application was showed.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.474-487
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• 1998

The present study was undertaken to investigate the morphological characteristics of trigeminal nerve in the Korean native goat by macroscopic methods. Trigeminal nerve was originated from the lateral side of pons, and extended shortly forward to form trigeminal ganglion at the opening of oval foramen. Thereafter this nerve was divided into maxillary, mandibular and ophthalmic nerve. Ophthalmic nerve gave off the zygomaticotemporal branch, frontal nerve, frontal sinus branch, and was continued as the nasociliary nerve. Maxillary nerve gave rise to the zygomaticofacial branch, accessory zygomaticofacial branch, communicating branch with oculomotor nerve, pterygopalatine nerve, caudal superior alveolar branch, malar branch and was continued as the infraorbital nerve. Mandibular nerve was divided into the masseteric nerve, buccal nerve, lateral pterygoid nerve, medial pterygoid nerve, nerve to tensor tympani m., auriculotemporal nerve, and furnished the inferior alveolar nerve and lingual nerve as terminal branches. The course and distribution of the trigeminal nerve in the Korean native goat appeared to be similar to that in other small ruminants such as sheep and goat. But the main differences from other small ruminants were as follows : 1. There was no accessory branch of the major palatine nerve. 2. The caudal superior alveolar branch was directly branched from the maxillary nerve. 3. The communicating branch with oculomotor nerve was originated from maxillary nerve or common trunk with zygomaticofacial branch. 4. The malar branch arose from the maxillary nerve at the rostral to the origin of the caudal superior alveolar branch. 5. The inferior alveolar nerve originated in a common trunk with the lingual nerve. 6. The mylohyoid nerve arose at the origin of the inferior alveolar nerve. 7. The zygomaticotemporal branch was single fascicle, and gave off lacrimal nerve and cornual branch. 8. The base of horn was provided by the cornual branches of zygomaticotemporal branch and infratrochlear nerve of nasociliary nerve.