• Korean Journal of Environmental Agriculture
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• v.3 no.2
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• pp.55-61
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• 1984

농업(農業)은 동식물(動植物)을 대상으로 하는 응용생태학(應用生態學)의 한 분야(分野)로 그의 발전과정(發展過程)은 환경(環境)과 밀접(密接)한 관계가 있다. 환경조건(環境條件)의 다양성(多樣性)은 대상생물(對象生物)의 종류(種類)를 풍부하게 하고 순화(馴化)된 생물(生物)의 사양(飼養) 과정에서 다양(多樣)한 농업형태(農業形態)를 발전시켰다. 생웅계(生熊系)는 자연(自然)의 한 단위로 구성요소(構成要素)들은 기능적(機能的)으로 통일성(統一性)을 유지하고 있다. 농생태계(農生態系)는 생산(生産)을 목표(目標)로 하는 동식물(動植物)을 중심(中心)으로 하는 생태계(生態系)로 자연생태계(自然生態系)와 기본적(基本的) 성질(性質)은 동일하나 인위적(人爲的) 요소(要素)가 크게 작용하고 있는 특리(特異)한 생태계(生態系)이다. 작물(作物)이나 가축(家畜)은 수천년에 걸친 생산력(生産力)의 증대(增大)를 목표(目標)로 인위적(人爲的)인 선발을 거친 것으로 자연조작하(自然條作下)에서 심한 경쟁(競爭)을 거치면서 진화(進化)한 야생생물(野生生物)들에 비하면 선천적(先天的) 포약성(胞弱性)을 갖고 있어 인간(人間)의 보호(保護)(에너지보조(補助))를 필요로 하고 있다. 농생태계(農生態系)는 공간적(空間的) 격리(隔離)와 구성종(構成種)의 단순화(單純化)로 공간적(空間的) 연쇄성(連鎖性)과 종다양도(種多樣度)가 큰 자연생태계(自然生態系)에 비하면 외적(外的) 충격에 대한 내부적(內部的) 완충능력(緩衝能力)이 약하다. 더우기 농생태계(農生態系)는 시간적(時間的) 연속성(連續性)이 없어 극상천이(極相遷移)단계에 달할 수 있는 시간적(時間的) 여유가 없어 생물상호간(生物相互間)의 관계는 초기(初期) 천이(遷移)단계의 특성(特性)인 종다양도(種多樣度)가 낮고 직선적(直線的)이고 단순(單純)한 먹이연쇄성(連鎖性)을 갖고 있다. 생물군집(生物群集)의 천이진행(遷移進行)에 따르는 종다양도(種多樣度)의 증가(增加)는 생물군집내(生物群集內) 현재량(現在量) 증가와 더부러 먹이 연쇄상(連鎖相)을 직선상(直線狀)에서 망상(網狀)으로 변화시키고 주된 물질(物質)${\cdot}$유전회로(流轉回路)를 포식(捕食)먹이 연소회로(連銷回路)에서 부식(腐食)먹이연쇄회로(連鎖回路)로 전환시켜 생태계(生態系)의 물질(物質)은 생태군집내(生態群集內)에 보존(保存)하는 능력(能力)을 증대(增大)시키고 토양(土壤)의 물리(物理) 화학적성질(化學的性質)을 개선하여 계내(系內) 물질(物質)의 유실(流失)을 억제하기도 한다. 농생태계(農生態系)는 생산성(生産性)의 증대(增大), 관리(管理)의 편의(便宜) 기타의 이유(理由)로 구성종수(構成種數)를 인위적으로 제한(制限)하고 관리(管理)를 통하여 발아(發芽), 생장(生長), 개화(開花)등 여러가지 생물학적(生物學的) 현상을 극도로 균질화(均質化)시키고 있어 어떤 생육단계(生育段階)의 생물(生物)이 넓은 면적(面積)에 동시에 존재하게 되는데 이것은 외적조건(外的條件)의 변동(變動)에 대한 감수성(感受性)을 증대시킨다. 이와 같은 자연생태계(自然生態系)와 농생태계(農生態系)의 생태학적(生態學的) 특성(特性)에 관한 이해(理解)와 인식(認識)은 농생태계(農生態系)의 생산성(生産性) 증대(增大)와 영구적(永久的) 유지(維持)를 위한 합리적(合理的) 관리(管理)를 위한 기본(基本)이 될 것이다.

• Journal of KIISE:Computer Systems and Theory
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• v.31 no.9
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• pp.514-526
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• 2004

Microarray is a new technique for gene expression experiment, which has gained biologist's attention for recent years. This technology enables us to obtain hundreds and thousands of expression of gene or genotype at once using microarray Since it requires manual work to analyze patterns of gene expression, we want to develop an effective and automated tools to analyze microarray image. However it is difficult to analyze DNA chip images automatically due to several problems such as the variation of spot position, the irregularity of spot shape and size, and sample contamination. Especially, one of the most difficult problems in microarray analysis is the block and spot addressing, which is performed by manual or semi automated work in all the commercial tools. In this paper we propose a new algorithm to address the position of spot and block using a new concept of regular structure grid searching. In our algorithm, first we construct maximal I-regular sequences from the set of input points. Secondly we calculate the rotational angle and unit distance. Finally, we construct I-regularity graph by allowing pseudo points and then we compute the spot/block address using this graph. Experiment results showed that our algorithm is highly robust and reliable. Supplement information is available on http://jade.cs.pusan.ac.kr/~autogrid.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.2
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• pp.122-134
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• 2020

On the many coasts of South Korea, including the eastern side, it has been recently increasing the coastal disaster such as the severe coastal erosion and road damage swept away by the wave. As one of the alternatives to prevent the coastal disaster, it has been widely studied the coastal disaster reduction method by the Low-Crested Structure (LCS) in the many countries including several European countries. In this study, the olaFLow model is used to simulate the permeable LCS and wave field of the LCS through the three-dimensional irregular waves numerical analysis on the basis of the previous research. From the numerical analysis, it is evaluated the H_rms, nearshore current and time-averaged turbulent kinetic energy. In addition, the pattern of nearshore current and spatial distribution of time-averaged turbulent kinetic energy are compared with the case of submerged breakwater under the irregular wave fields. As one of significant results, it is confirmed that the pattern of nearshore current is different with the case of submerged breakwater.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.33-40
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• 2021

Measuring the compressive strength of concrete is a very important factor in the safety review of concrete structures. Concrete compressive strength measurement methods include destructive and non-destructive methods. The destructive method includes the uniaxial compression failure method, and the non-destructive method includes the rebound hardness method and the elastic wave measurement method. In this study, the type of measurement method and the effect of reinforcing bars inside the concrete were tested to examine the relationship between them. Regardless of the type of specimen, the average compressive strength by the elastic wave measurement method among the three experimental methods was greater than the average compressive strength by the other methods. When the specimen type is the same, the standard deviation of the measured values of the elastic wave measurement method is smaller than that of the other measurement methods, so it can be seen that the elastic wave measurement method does not show large variance in the measured values compared to the other two measurement methods. When the average compressive strength according to the test method for each specimen was compared with the average compressive strength of the compressive failure test method, the average compressive strength was measured to be high in the order of the elastic wave measurement method, the compression failure test, and the rebound hardness method. Since the measured values of the compressive strength of concrete are different depending on the method of measuring the compressive strength of concrete and the presence or absence of reinforcing bars inside the concrete, further research is required considering the effect of various concrete covers.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.3
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• pp.180-198
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• 2019

In recent years, countries like Europe and Japan have been involved in many researches on the Low-Crested Structure (LCS) which is the method to protect beach erosion and it is regarded as an alternative to the submerged breakwaters, and compiled its results and released the design manual. In the past, studies on LCS have focused on two-dimensional wave transmission and calculating required weight of armor units, and these were mainly examined and discussed based on experiments. In this study, three-dimensional numerical analysis is performed on permeable LCS. The open-source CFD code olaFlow based on the Navier-Stokes momentum equations is applied to the numerical analysis, which is a strongly nonlinear analysis method that enables breaking and turbulence analysis. As a result, the distribution characteristics of the LCS such as water level, water flow, and turbulent kinetic energy were examined and discussed, then they were carefully compared and examined in the case of submerged breakwaters. The study results indicate that there is a difference between the flow patterns of longshore current near the shoreline, the spatial distribution of longshore and on-offshore directions of mean turbulent kinetic energy in case of submerged breakwaters and LCS. It is predicted that the difference in these results leads to the difference in sand movement.

• Korean Journal of Environment and Ecology
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• v.30 no.6
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• pp.970-976
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• 2016

Determining age structure of the population of an endangered species is critical because it could provide basic information about population dynamics. In this study, we assessed the possibility if the growth lines on dorsal scutes of the national monument as well as endangered Reeves' turtle (Mauremys reevesii) can reliably estimate actual ages of the 100 turtles of which actual ages were known and have been housed in Seoul Zoo. We counted the number of growth lines on the first four dorsal scutes and the first left and right lateral scutes of each turtle and compared those with their known actual ages. Ages estimated by the growth lines were overestimated at between 1 and 5 actual ages, but underestimated at between 6 and 9 actual ages, indicating that age estimation using growth lines is only partially applicable at actual ages of less than 6 years old. In addition, using length and width of turtle's dorsal plates, we produced growth curves with equations to estimate actual ages of females combined with juveniles, but its application to estimate actual ages was not reliably possible because all subject turtles which used were at relatively young ages. In conclusion, when estimating actual ages of Reeves' turtles using the number of growth lines on the dorsal scutes, it is recommend to use minimum values at less than 6 lines, but use maximum values at more than 7 lines. As the first study which estimated actual ages of a turtle species using growth lines on the dorsal scutes in Korea, our results could be useful to estimate ages of the endangered Reeve's turtles in the field although its application might be limited.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.3
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• pp.149-159
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• 2012

To elucidate the species compositions of estuarine and inshore fauna and compare productivities between them, catch were collected by bag nets in the Han River estuary off Ganghwa Island and the inshore waters off Jangbong Island for 24 hours at the spring tide from March to December 2010. Community structures of nekton assemblages were different with area, month, taxonomic groups. Although the diversity of estuarine nekton assemblage was lower than that of inshore nekton assemblage, the productivity of nekton assemblage in estuary was higher than that in the inshore waters. Nekton assemblages were distributed according to habitat environment: the estuarine species, Coilia mystus, Chelon haematocheilus, Collichthys lucidus were prominent in the Han River estuary off Ganghwa Island, and marine species, Thryssa kammalensis, Sardinella zunasi, Portunus trituberculatus were prominent in the inshore waters off Jangbong Island. Palaemon gravieri, Exopalaemon carinicauda, Synechogobius hasta were inhabited in both waters. The health assessment of estuarine ecosystem based on scientific research will be contributed to the effective management of estuary with determination of order and direction in policy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.481-491
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• 2015

Since the crack in the surface of the concrete acts as the main reason influencing the life span of the structure, regular inspections and maintenance are required. The sealing required for maintenance of the concrete surface is a method of repairing the crack in the surface in the beginning, and is effective in preventing additional cracks and expansion that occurs with time. However, sealing on large sized structures such as tall buildings or bottom parts of bridges are difficult to ensure safety of the workers due to inadequate working environments. Due to this reason, the importance of the need for sealing automation for the maintenance of large sized concrete structures is emerging. This study proposes two control methods to apply robot systems to the sealing of cracks on the bottom parts of concrete bridges. First is the method of automatically tracking the trajectory of cracks. The robot gets the trajectory of the cracks using video information obtained from cameras. Comparing the previous several points and new point, the next point can be estimated. Thus, the trajectory of the crack can be tracked automatically. The other method is sealing by maintaining steady force to the contacting surface. The concrete surface exposed to an external environment for a long time gets an irregular roughness. If robots are able to carry out sealing while maintaining a steady contact force on these rough surfaces, complete equal sealing can be maintained. In order to maintain this equal force, a force control method using impedance is proposed. This paper introduces two developed control methods to apply to sealing robots, and conducts a Lab Test and Field Test after applying to a robot. Based on the test results, opinions on the possibilities of field application of the robot applied with the control methods are presented.

• KDI Journal of Economic Policy
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• v.32 no.3
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• pp.1-32
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• 2010

The global financial crisis has exerted enormous impacts on the attainment of inflation target in Korea. The annual average CPI inflation was 3.3% during the targeting period of 2007-2009 and the target was $3.0{\pm}0.5%$. Thus Korea has succeeded in keeping annual average CPI inflation just below the upper limit of the 2007-2009 target under the global crisis. This paper intends to evaluate the performance of the inflation targeting system in Korea. First, it estimates the conventional call rate reaction equation under the global crisis and finds that the policy interest rates never reacted to expected inflation, output gap, and won/dollar exchange rate, as expected by theory. Second, it identifies the shock of global financial crisis into core and non-core, applying the structural VAR model. The core shock was defined to have no (medium- to) long-run impact on real output. The core shock was identified to have the character of the demand shock, since it has the positive impact on the inflation and output in the short run. The structural core inflation due to core shock was an attractor of headline inflation, not vice versa. Therefore, the structural core inflation that reflects the demand-side shock would be the better intermediate target for the final headline inflation target than the official core inflation that excludes the volatile inflation of agricultural and oil-related products. During the inflation targeting period of 2007-2009, the structural core inflation was more volatile than the official core inflation, because the global crisis has very large negative impacts on the domestic demand as well as the prices of agricultural and oil-related products. This paper shows that the negative core shock during the fourth quarter of 2008 was larger than that in the financial crisis in 1998. But the core shock turned into positive very quickly in 2009, as the Korean economy recovered very quickly from crisis. The volatile changes in structural core inflation suggests that the Bank of Korea barely managed to attain the 2007-2009 inflation target, owing to the very large negative impacts of the global financial crisis on the domestic demand. It also suggests that the rapid rise in core inflation with the rapid recovery of the Korean economy will lead to rapid rise in headline inflation.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.4
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• pp.39-53
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• 2013

Although the efficient formation of urban space structure is a key factor in energy saving and environmentally-friendly aspect, the maintenance of the center and sub-center of the city that are key factors has been becoming increasingly difficult due to the variability and complexity of urban activities. In the case of Busan, amid the expansion of urban scale due to rapid economic development and overpopulation, systematic approaches to professional diagnosis and maintenance have been significantly insufficient - other than the city basic plan which has been conducted at an interval of 20 years. For the effective management of urban central area, systematic monitoring of the CBD through demand forecast and blight forecast at a city level must first be implemented. In order to fulfill this goal, this study is to figure out the current state of the CBD through the diagnosis on blight of the urban central area in the viewpoint of rehabilitation of the CBD and to propose the measures for practical utilization of the information about space for the further management of the central area of the city. For analysis, the study looks into the present state in terms of physical index, economic index, and social index. And then as a micro-approach by utilizing economic index, the study has thoroughly examined the economic blight of the Seomyun urban central area of Busan. The outcome of the analysis shows that in terms of population distribution and land utilization the area is in the stage of inefficient dispersion after having gone through the stage of suburbanization. It is expected that this study, as the material that proves the necessity of enhancing the function of the CBD, can propose the direction for the management of the urban center of Busan through blight prediction and management of the urban center and can provide the basic data for the long-term urban development that aims at the efficient strengthening of functions of the CBD.