• Journal of the Korean Wood Science and Technology
• /
• v.28 no.2
• /
• pp.66-74
• /
• 2000

Wood of black locust(Robinia pseudoacacia) and bark of poplar(Populus alba x glandulosa), ash(Fraxinus rhynchophylla) and elm(Ulmus davidiana var. japonica) trees were collected, extracted with acetone-$H_2O$(7:3. v/v), fractionated with hexane, chloroform, ethylacetate and $H_2O$. then freeze dried to get some dark brown powder for bioactive tests. Decay-resistant activity was tested using wood block specimens from the hardwood trees and expressed by weight loss rate. Black locust specimens indicated the best anti-decaying property and poplar blocks were the worst. Antimicrobial and antioxidant activities were also investigated against each wood or bark extractives. Antifungal and antibacterial activities did not indicate any significant differences among the tested fractions. In antioxidant activity. ${\alpha}$-tocopherol one of natural antioxidants. and BHT, one of synthetic antioxidants, were used as references to compare with the antioxidant activities of the extracted fractions. Ethylacetate fraction of ash bark indicated the highest activity besides BHT in this test and all fractions of black locust extractives also indicated higher activities compared with the other fractions.

• Journal of Applied Biological Chemistry
• /
• v.62 no.1
• /
• pp.31-38
• /
• 2019

Scutellaria baicalensis Georgi (Scutellariae Radix) has been widely used as a dietary ingredient and traditional herbal medicine such as diuretic, hyperlipidemia, antibacterial, anti-allergy, anti-inflammatory and anticancer properties. In this study, the isolation of biomarkers or bioactive compounds from complex S. baicalensis extracts represents an essential step for de novo identification and bioactivity assessment. The bioactive fraction consisted of eight compounds which was chromatographed on an analytical high performance liquid chromatography column using two different gradient runs. A simulative replacement of the analytical column with a medium pressure liquid chromatography and open column allowed the determination of gradient profile to allow sufficient separation in the preparative scale. From the optimized method, eight standard compounds have been identified in the fractions. In addition, MS, UV, HRMS detection was provided by ultraperformance liquid chromatographyequadrupole time-of-flight mass spectrometry (UPLC-QTof-MS) of all fractions. Therefore, this scale up procedure was successfully applied to a S. baicalensis extract.

• Journal of Advanced Navigation Technology
• /
• v.24 no.6
• /
• pp.515-520
• /
• 2020

The development of autopilot system and flight management system (FMS) equipment in today's aircraft navigation can be attributed to the reduction of pilots' workload and the navigation safety. The effect of autopilot and FMS equipment is greater, especially in heavy airport traffic or complicated of the departure. However, some airport specific departure procedures result in an uncommanded turn event due to an error in the FMS, causing aircraft to deviate from the center line of the route. With most departure procedures requiring area navigation (RNAV) operation, pilot situation awareness and corrective action are the only ways to minimize aircraft deviation to maintain the safety of area navigation. Through analysis of the occurrence status of the uncommended turn event by aircraft type, airport and flight phase, and comparative analysis of the survey results of foreign airlines and the airlines self-reduction plan with the aircraft manufacturer's corrective action, it is intended to give implications for the need for more fundamental measures to prevent recurrence of such events.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2023.05a
• /
• pp.76-76
• /
• 2023

최근 자율주행과 관련한 시장의 관심은 기존 자동차 자율주행에서 선박 자율운항으로 자연스럽게 이동하고 있다. 이에 인공지능 및 빅데이터 등과 같은 최근 기술을 선박 자율주행에 적용하는 자율운항선박(MASS: Maritime Autonomous Surface Ship) 개발이 활발히 진행되고 있으며, 레이더 및 카메라 등과 같은 센서 정보를 선박 자율운항에 적용하여 다양한 선박 운동 및 정보를 획득하는 연구 기술이 집중되고 있다. 이러한 경향에 따라 IMO(International Maritime Organization)과 같은 국제기구에서도 자율운항선박 표준화 본격 논의로 기술표준 선점 경쟁에 참여하고 있다. 이 중 연안 자율운항선박 개발은 IMO에서 주관하는 무인화 핵심기술로 여겨지고 있어, 기존 대양 항해 기술과 함께 연안 항해에 대한 기술 개발의 중요성이 높아지고 있다. 특히 항만 인근 해역에서는 다수의 선박이 입출항함으로 인해 해상에서의 안전과 물류의 효율화가 요구되기 때문에 고도화된 자율운항 기술개발이 필요하다. 하지만 자율운항선박에서의 상황인식 기술은 탑재된 센서의 제한된 시야각 및 기상조건에 따른 인식률이 떨어지는 문제가 생긴다. 이러한 기술적 한계를 극복하기 위해 육상에 설치된 레이더를 활용하여 선박을 탐지할 수 있는 기술이 필요하다. 본 연구에서는 고해상도 육상 레이더를 기반하여 얻어진 레이더 화면상의 물표 정보를 이용해 인공지능 기법에 활용하기 위한 라벨링 자동 생성 방법에 대해 소개한다. 얻어진 물표 정보에 인공지능 기법을 적용하여 선박 길이 정보를 추정하는 기술에 대해 소개한다.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2020.08a
• /
• pp.56-56
• /
• 2020

봄철 새순을 식용하는 두릅나무는 기능성 건강식품으로 각광을 받고 있어, 생리활성이 뛰어난 고품질의 두릅나무 신품종을 개발하여 고부가가치 창출 및 상업적 용도로 활용하고자 본 연구를 수행하였다. 두릅나무 선발개체, 상업적으로 판매되고 있는 지역종 및 일본품종 등 총 46개체의 새순 특성을 조사하고, 이들 중 새순 특성이 우수한 25개체의 항산화, 항노화, 미백저해 활성 및 항염증 활성 등 생리활성 분석을 실시하였다. 새순 특성을 조사한 결과, 「임산물표준규격」에 따른 등급 구분에서 46개 수집 개체 중 13개 개체가 '특'품에, 22개체는 '상'품에 해당하였다. 특히, 원주에서 선발한 개체들은 새순 굵기가 2.2±0.2cm, 새순 1개의 무게가 49.5±7.6g으로 지역종 및 일본 품종과 비교했을 때 새순 특성이 2~3배 우수한 것으로 나타났다. 생리활성 분석결과 항노화 활성, 미백 저해 활성 및 항염증 활성은 선발개체가 일본품종과 지역종에 비해 우수한 반면 항산화 활성은 낮게 나타났다. 생리 활성이 우수한 선발개체의 일반성분 함량은 일본품종과 지역종에 비해 낮았으나, Ca 등의 무기성분 함량은 더 높았다.

• The Korean Journal of Applied Statistics
• /
• v.37 no.1
• /
• pp.39-48
• /
• 2024

In this paper, we introduce an extended GARCH model designed to address asymmetric leverage effects. The variance in the standard GARCH model is composed of past conditional variances and past squared residuals. However, it is not possible to model asymmetric leverage effects with squared residuals alone, so in this paper, we propose a new extended GARCH model to explain the leverage effects using the Yeo-Johnson transformation which adjusts transformation parameter to make asymmetric data more normal or symmetric. We utilize the reverse properties of Yeo-Johnson transformation to model asymmetric volatility. We investigate the characteristics of the proposed model and parameter estimation. We also explore how to derive forecasts and forecast intervals in the proposed model. We compare it with standard GARCH and other extended GARCH models that model asymmetric leverage effects through empirical data analysis.

• Tuberculosis and Respiratory Diseases
• /
• v.54 no.3
• /
• pp.274-282
• /
• 2003

Background : Tuberculous lymphadenitis is one of the most common forms of extrapulmonary tuberculosis. It was recently reported that the treatment for tuberculous lymphadenitis could be shortened to 6 months without increasing the risk of a relapse. However, there is no report of a prospective randomized study on the use of 6-month chemotherapy with HERZ for cervical lymphadenitis, which is regimen recommended in the areas concerned with the initial drug resistance. The aim of this study is to evaluate the efficacy of the 6-month regimen with HERZ for cervical lymphadenitis in areas where there is a high prevalence of drug resistance in Korea. Method : From January 1997 to February 2002, 92 patients with cervical tuberculous lymphadenitis were recruited from Kyungpook national university hospital. Forty-six patients were given the 6-month regimen(2HERZ/4HER) and the other forty-six patients were given the 9-month regimen(2HERZ/7HER). Result : Of the 46 patients given the 6-month regimen, 5 had residual lymph nodes greater than 5 mm after the completion of treatment and 3 had new lymph nodes or an increased lymph node size during the follow-up period. Of the 46 patients in the 9-month regimen, 9 had residual lymph nodes and 8 had new events during the follow-up period. There were no significant differences between the two groups. Conclusion : These results suggest that the 6-month HERZ regimen can be used safely as the initial treatment for tuberculous lymphadenitis in areas with a similar prevalence of drug resistance.

• Korean Journal of Poultry Science
• /
• v.20 no.2
• /
• pp.65-72
• /
• 1993

The experiment was conducted to estasblish the large scale production of anti-serum against chicken IgG and to profile the developmental changes of serum IgG levels during all the feeding period(from hatching to 7 weeks of age) in broiler chicks. Blood sample were taken from Hubbard chicken hi-daily or /and weekly during the experimental period. The pure IgG was isolated from ammonium sulfate treated chicken serum by ion exchange chromatography. The quantitative assay of serum IgG were carried by RID method. It was observed that IgG concentrations were showed the highest at hatching(4.25 $m\ell$/$m\ell$), after that dicreased rapidly, lowest at 2 weeks of age(0.81 $m\ell$/$m\ell$), and gradually increased to 7 weeks of age (2.48 $m\ell$/$m\ell$) There was no differences of IgG level between sex, but the IgG levels of male chicks dicreased more rapidly and increased earlier thereafter than those of females during the first two weeks of agg.

• Journal of Navigation and Port Research
• /
• v.38 no.2
• /
• pp.185-191
• /
• 2014

With the 500th anniversary commemoration of Gerard Mercator's birth in 2012 now passed, there is the possibility that his name will fade back into obscurity. This would be both unfair and pitiful, because Gerard Mercator's name should be highly regarded as one of the principal contributors to navigational science and the promotion of marine safety. An accomplished cartographer, in 1569 Mercator published a remarkable 18-folio world map, depicting the then-known world in a new format with straight rhumb lines. While this distorted the size of land masses, particularly in higher latitudes, this new projection made navigation much easier for now all sailors had to do was to draw a straight line between two points to plot their course. Mercator clearly had this navigational benefit in mind, though his contemporaries did not immediately recognize its value. It wasn't until after Mercator's death, when Edward Wright (1599) and Henry Bond (1645) used and explained the new projection and demonstrated the use of straight rhumb lines in navigation that the Mercator projection became the standard for sea charts. Today, 450 years later of his death, electronic charts still rely on the projection Mercator invented and developed, confirming his position as a giant in the history of navigation. This paper introduces his life and work, detailing the importance of the 1569 world map and its contribution to navigational science and safety.

• Journal of Korea Port Economic Association
• /
• v.30 no.3
• /
• pp.121-140
• /
• 2014

The purpose of this study is to identify economic benefits for analyzing the future port and propose an appropriate estimation model. This research has conducted the empirical analysis in order to examine the developed research model. First of all, several existing economic benefits are reviewed and the list of benefits, are able to quantify and characterizable, is selected for the next step. We test the application possibility of the proposed model applying for the three suggestions(AS/RS, OSS, Sky Rail) which are based on "Development of Smart Green Container Terminal Technology." The results of this paper are as follows: Firstly, all of the alternatives are proved economic validation because the values of B/C analysis are over 1.0. Secondly, sensitive analysis is attempted to test unforeseeable circumstances based on the cost increases. The result of the test is identified economic validation as well. Lastly, we convince that the proposed research model in this study is particularly applicable to future container terminal so-called "eco-friendly and fully automated container terminal with high productivity."