• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.1
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• pp.41-49
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• 2014

This study spatially assesses the impact of trees on residential rooftop solar energy potential using urban three-dimensional models derived from Light Detection and Ranging(LiDAR) data in San Francisco, California. In recent years on-site solar energy generation in cities has become an essential agenda in municipal climate action plans. However, it can be limited by neighboring environments such as shade from topography, buildings and trees. Of all these effects, the impact of trees on rooftop photovoltaics(PVs) requires careful attention because improper situation of solar panels without considering trees can result in inefficient solar energy generation, tree removal, and/or increasing building energy demand and urban heat island effect. Using ArcMap 9.3.1, we calculated the incoming annual solar radiation on individual rooftops in San Francisco and the reduced insolation affected by trees. Furthermore, we performed a multiple regression analysis to see what attributes of trees in a neighborhood(tree density, tree heights, and the variance of tree heights) affect rooftop insolation. The result shows that annual total residential rooftops insolation in San Francisco is 18,326,671 MWh and annual total light-loss reduction caused by trees is 326,406 MWh, which is about 1.78%. The annual insolation shows a wide range of values from $34.4kWh/m^2/year$ to $1,348.4kWh/m^2/year$. The result spatially maps the locations that show the various levels of impact from trees. The result from multiple regression shows that tree density, average tree heights and the variation of tree heights in a neighborhood have statistically significant effects on the rooftop solar potential. The results can be linked to municipal energy planning in order to manage potential conflicts as cities with low to medium population density begin implementing on-site solar energy generation. Rooftop solar energy generation makes the best contribution towards achieving sustainability when PVs are optimally located while pursuing the preservation of urban trees.

• Korean journal of communication and information
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• v.37
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• pp.204-236
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• 2007

This study explores the corrections on the Korean and the U. S. daily newspapers for the characteristics and differences through the content analysis. For the research, Chosun Ilbo, Hankyoreh Shinmun, The New York Times and The San Francisco Chronicles are selected. The main differences between the Korean and American newspapers are as follows: Firstly, the average number of newspaper errors in Korean dailies are as half as little of those in the U. S. dailies. Secondly, regarding the subcategory of mistakes, the largest thematical number is the societal matters(36.0%), followed by politics(18.3%) and economy(12.1%) for the Korean newspapers. By contrast, errors in culture(17.4%) is the most frequently made by the American newspaper reporters and editors, followed by lifestyle(8.6%), and sports(7.0%). Thirdly, in terms of content of mistakes, errors in names(26.2%) that occurred the most, followed by misidentifications(18.1%) and misattribution(15.8%) for the Korean dailies; the errors in numbers(33.7%), spelling and typographical errors(12.1%) and date(5.6%) for the U. S. dailies. Fourthly, one of the critical reasons that mistakes occurred because Korean reporters are lack of double checking the stories; the U. S. reporters simply by overlooking the articles. Finally, the Korean newspapers make use of only two kinds of correction formats, while the U.S. newspapers use six different correction formats for their newspaper readers.

• Journal of Korea Water Resources Association
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• v.31 no.5
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• pp.613-620
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• 1998

Field and laboratory studies of the near field behavior of the San Francisco ocean outfall were reported. The data sets cover broad ranges of discharge conditions and oceanic conditions, and are associated with a typical type of outfall discharges with multiport diffusers. The laboratory data sets were obtained in density-stratified towing tanks to replicate the field tests. Model studies of wastefield behavior using these data sets were predicted by the mathematical models UM, UDKHDEN, RSB, and CORMIX2 for minimum dilution, the height to top of wastefield, and wastefield thickness. In this paper, the results are discussed and compared measurements with mathematical model predictions. The hydraulic model studies reproduced the major features observed in the field. It also afforded considerable insight into the mechanics of mixing of multiport risers which could have been obtained neither from the field test nor the mathematical models.

• Journal of the Korea Convergence Society
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• v.10 no.4
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• pp.33-38
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• 2019

Recently, to support location-based services, there have been many researches which consider the spatial network. For this, there are many experimental data for data processing on the road network. However, the data to process the trajectory of moving objects are not suitable. Therefore, we propose index structure to process the trajectory data on the road network and the trajectory data generation algorithm. In addition, to prove efficiency of our index structure and algorithm, we show that edge-based trajectory data are generated through the proposed algorithm using the map data of San Francisco Bay.

• KIEAE Journal
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• v.8 no.3
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• pp.61-68
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• 2008

The development of urbanization in the twentieth century according to the rampant growth of industrialization not only brought about the improvement of life-quality but also induced us to reconsider the contemporary issues such as crisis of echo system which made us aware of the values and significance of the system and sustainable environments. As sustainability has been recognized as the holistic concept, it has been highlighted as one of the core concepts in the studies with the present ecological perspective. Particularly, as the plan of urbanization in Korea which had been based on the deconstruction has been converted into the regeneration, economic and cultural regeneration is also demanded for the future plan besides material regeneration. This study aims to scrutinize various attributes of socially sustainable designs in Yerba Buena Garden of San Francisco, USA which has been globally well known as a successful example of urban regeneration. By way of visit-and-observation of the place, the research for the study was conducted during the month of December, 2007. Three researchers visited Yerba Buena Garden to observe and take photographs and to obtain relevant data and public documents in local public library. Socially sustainable design was measured on the basis of such principles; social facilitation, permeability and accessibility, safely and emotional stability, softness and feminism, and child care convenience. Relevant data were systematically organized to support and prove the above principles. The result of the study is expected to effectively be utilized for Korean environment plan and design as a benchmarking guidelines against the crisis of degeneration and the aging society with the lowest birthrates in the world.

• Journal of the Korean Data and Information Science Society
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• v.26 no.5
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• pp.1097-1104
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• 2015

Rapid social and economic growth has brought positive results. At the same time, due to the increase in crime, crime prevention is important. There are many papers that analyze crime trends and crime type. Based on this, there are studies to ensure the safety of people. The study calculated the risk for the crime. it is necessary to exert a great effect on crime prevention alternatives. This paper uses crime data provided from San Francisco and victims data provided from FBI. And, it proposes the crime risk calculation. By analyzing the type of user, risk degree is given different weights according to the user, and assess the risk of crime.

• Journal of Arbitration Studies
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• v.18 no.2
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• pp.201-233
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• 2008

러시아와 한국간의 공식적인 접촉은 1990년 6월 샌프란시스코에서 개최된 정상회담이다. 동년 9월 뉴욕에서 개최된 양국의 외무장관 회담에서 러시아와 한국의 외교관계가 수립되었다. 그간 양국간에는 협정을 통한 협력의 법적기반이 조성되었는데 주요 분야를 보면 무역, 투자보장, 어업, 이중과세방지, 군사기술분야, 원자력의 평화적 이용, 문화교류에 관한 협정들이 있다. 역시 양국간의 주요 관심사항은 무역과 경제협력 분야이다. 2007년도 러시아와 한국의 무역액은 150억 달러를 초과함으로써 전년도에 비해 55.5% 증가하였다. 러시아의 한국으로의 수출은 약 70억 달러로서 전년도에 비해 52.6% 증가했고 한국으로부터의 수입은 80억 달러를 초과함으로써 전년도에 비해 56.1% 증가하였다. 그리하여 러시아는 한국의 10대 교역국으로 성장하였다. 가스와 오일 프로젝트 추진과 관련하여 사할린지역에서 사용하기 위해 한국으로부터 수입하는 드릴기계장비, 탱커, 자동차, 휴대전화는 한국과 러시아 양국간 경제성장의 주요요인이 되고 있다. 2008년 1/4 분기 양국간 무역액은 42억 달러를 초과했는데 이는 전년도 동기와 비교해서 72.1% 증가한 것이다. 이 중 한국에의 수출은 17억 달러를 초과했는데 이는 전년도 1/4분기에 비해 91.7% 성장한 것이다. 한국으로부터의 수입은 약 25억 달러로서 전년도 1/4 분기와 대비해서 60.6% 성장했다. 러시아와 한국간의 경제교류가 크게 증대하게 된 배경에는 러-한경제과학기술협력공동위원회가 큰 역할을 담당했다. 이 논문에서 필자는 무역과 투자측면에서 본 양국간 경제협력의 특징을 고찰하는 한편 러시아의 동부지역(러시아 극동 및 바이칼횡단지역)과 한국과의 협력과 관련된 역동성과 과제를 제시하는데 연구의 목적을 두었다. 한국은 외국기업과 함께 러시아 극동지역의 무역과 경제협력 증진에 상당한 공헌을 함으로써 러시아 극동경제권에서 주요 무역파트너가 되고 있다. 또한 본 연구에서는 한국과 러시아간의 주요 협력프로젝트에 관하여 고찰하는 한편 앞으로의 전망을 제시하였다. 이 문제는 무엇보다도 한-러간의 공동 에너지프로젝트 및 에너지자원의 무역과 관련되어 있다. 한국과 러시아는 이미 많은 분야에서 상당한 정도로 상호 협력관계를 발전시켜왔다. 여기에는 정책, 에너지, 경제, 문화, 과학기술 분야가 포함되어 있다. 현재 러시아와 한국간에는 에너지 분야에서의 전략적 대화채널 구축에 관한 문제와 함께 연료 및 에너지공단 건설과 관련하여 협력문제가 논의되고 있다. 에너지 분야에서의 전략적 대화개념 구축을 위해서는 전략, 예측 및 투자환경의 문제가 양국간에 집중논의 되어야 하고 법제상의 조화문제도 논의되어야 한다.

• Journal of Aquaculture
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• v.11 no.1
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• pp.99-103
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• 1998

Artemia often observed as a co-existing organism in the mass culture tank of marine rotifer. The rotifer and Atremia are commonly used as food organisms in the marine fish larvae rearing. In this study, interspecific relation between the rotifer Brachionus rotundiformis (formely called S-type) and anostracan Artemia of the two developmental stages (0 and 19 day old after hatching) were investigated in the larboratory. The population growth of B. rotundiformis and one of the stage (nauplius or adult) of Artemia in mixed culture was compared with that of each single species culture. Culture period was 16 days. Every two days, the number of organisms in each species was counted and transferred to a fresh medium containing $7{\times}10^5$cells/ml of food Nannochloropsis oculata. Culture volume, temperature, salinity and photoperiod were set at 40ml, $25^{\circ}C.$, 22ppt and 24h all dark except to observation time, respectively. The rotifer population growth was greatly decreased by co-existence with Artemia. The coexisting Artemia suppressed the rotifer population growth due to it's high filtering speed for food (N. oculata). This study suggested that contamination by Artemia must be prevented for the stable rotifer production in the rotifer mass culture tank.

• Journal of Advanced Navigation Technology
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• v.25 no.3
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• pp.248-255
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• 2021

The main causes of the July 2013 OZ 214 accident were poorly performed approach and the failure to recognize the autothrottle in the HOLD position which the automated speed control was not provided. The pilots late decision for go-around was also a critical factor leading to the accident. The B777 POM restricts the use of FLCH mode beyond the FAF. This research utilized the QAR data of an airline's B777 fleet in the period of two years where 44 cases were found. In many cases, the FLCH mode was used for rapid descent from an higher than normal situation. In addition, in the base turn, continuous use of FLCH mode even when the path was below the glide path were observed. Airports with elevation above 500 ft MSL had a higher rate of occurrence. In this research, the proper descent planning and vertical path monitoring, and the adherence to the limitation set in the manuals and the stabilized approach criteria were re-emphasized as mitigation to reduce event occurences.

• Korean Journal of Remote Sensing
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• v.36 no.6_2
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• pp.1615-1627
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• 2020

The purpose of this study is to compare and analyze the performance of KOMPSAT-3 Digital Surface Model (DSM) made in overseas testbed area. To that end, we collected the KOMPSAT-3 in-track stereo image taken in San Francisco, the U.S. The stereo geometry elements (B/H, converse angle, etc.) of the stereo image taken were all found to be in the stable range. By applying precise sensor modeling using Ground Control Point (GCP) and DSM automatic generation technique, DSM with 1 m resolution was produced. Reference materials for evaluation and calibration are ground points with accuracy within 0.01 m from Compass Data Inc., 1 m resolution Elevation 1-DSM produced by Airbus. The precision sensor modeling accuracy of KOMPSAT-3 was within 0.5 m (RMSE) in horizontal and vertical directions. When the difference map was written between the generated DSM and the reference DSM, the mean and standard deviation were 0.61 m and 5.25 m respectively, but in some areas, they showed a large difference of more than 100 m. These areas appeared mainly in closed areas where high-rise buildings were concentrated. If KOMPSAT-3 tri-stereo images are used and various post-processing techniques are developed, it will be possible to produce DSM with more improved quality.