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On response of Surface Equilibrium Temperature for Change of Surface Characteristics : An EBM Study (지표 특성 변화에 대한 평형온도의 반응 연구 : EBM 연구)

  • Seo, Ye-Won;Chu, Jung-Eun;Ha, Kyung-Ja
    • The Korean Journal of Quaternary Research
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    • v.24 no.2
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    • pp.1-11
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    • 2010
  • Energy Balance Model (EBM) was used to experiment the distribution of surface equilibrium temperature which responds to external forcing associated with the surface characteristics. Surface equilibrium temperature is calculated as sum of incoming solar radiation and latitudinal transport is balanced with outgoing infrared radiation. To treat incoming solar radiation, the source of the earth energy, significantly for energy balance, the experiment for surface equilibrium temperature distribution was performed considering the energy balance with the latitudinal albedo change as well as land and sea distribution. In addition, linear albedo change experiment, arctic albedo 5%, 10%, 15% change experiments and the opposite albedo change experiments between arctic and mid-latitudes were performed using incoming solar radiation as an external forcing. Moreover, with and without ice-albedo feedback experiments were performed. Increasing of arctic albedo is blocked out the incoming solar radiation so that it induces decreasing of latitudinal heat transport. It is strengthened energy transport from low latitudes by keeping arctic low energy states. Therefore the temperature change in the mid-latitudes exhibits larger response than that of arctic due to the difference of transport. The land which has lower heat capacity than sea can be reach to equilibrium temperature shortly. Also land is more sensitive to temperature change with respects to albedo. Thus it induces the thermal difference between land and sea. As a result, the equilibrium temperature exhibits differently as the difference of albedo and heat capacity which are the one of surface characteristics. Surface equilibrium temperature decreases as albedo increase and the ratio of temperature change is large as heat capacity is small. The decreasing of surface equilibrium temperature with respects to increasing of linear albedo is accelerated by ice-albedo feedback. However local change of surface equilibrium temperature decreases non-linearly.

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Fine Structure on the Pigment Epithelial Cell and the Bruch's Membrane of the Rat Retina after X-Irradiation (X-선 조사를 받은 흰쥐 망막의 색소상피세포와 기저복합층의 미세구조)

  • Ko, Jeong-Sik;Shin, Ki-Ho;Ahn, E.Tay;Yang, Nam-Gil;Park, Kyung-Ho;Kim, Jin-Gook
    • Applied Microscopy
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    • v.23 no.2
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    • pp.11-26
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    • 1993
  • This experiment was performed to study the morphological responses of the pigment epithelial cell and the Bruch's membrane of the retina of rat following X-ray irradiation. Male rats were divided into normal and experimental groups. The heads of the rats, under sodium thiopental anesthesia, were exposed to 3,000 rads or 6,000 rads of radiation in a single dose, respectively. The source was a Mitsubishi Linear Accelerator ML-4MV. The target to skin distance was 80cm, and the. dose rate was 200 rads/min. The experimental groups were sacrificed on the 6th hour, 2nd and 6th day after X-ray irradiation. Under anesthesia, 1% glutaraldehyde-1% paraformaldehyde solution(0.1M Millonig's phosphate buffer, pH 7.3) was perfused through the left ventricle and ascending aorta. Pieces of the tissue taken from the posterior region of the retina were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde(0.1M Millonig's phosphate buffer, pH 7.3) and 1% osmium tetroxide(0.1M Millonig's phosphate buffer, pH7.3), and embedded in araldite mixture. The ultrathin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100 CX-II electron microscope. The results were as follow; 1. The morphological changes of the pigment epithelial cells were not pronounced after exposure to 3,000 rads of X-ray. But on the 6th hour after exposure to 6,000 rads of X-ray, bulging nuclear membrane protruding into the cytoplasm and nuclear chromatin clumped into numerous masses along the nuclear membrane were observed. At the 2nd and 6th day post-irradiation, partial cytolysis or necrosis were seen. 2. The thickness of the Bruch's membrane of the experimental groups were increased in the time and dose range covered by this study, and splitting or diffusing basal laminae of the choriocapillary layer were observed frequently in the experimental group. Above results suggest that large amount(6,000 rads) of head irradiation induce direct hazardous effects on the pigment epitherial cells and Bruch's membrane of the retina of the rat, but pigment epithelial cells are more radioresistant than Bruch's membrane.

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Changes in the trends of dental caries patients in Korea -Based on patient survey data from 1990 to 2008- (1990년대 이후의 한국인 치아우식증 외래환자 수 변화 -1990~2008년 환자조사 자료에 근거하여-)

  • Choi, Yong-Keum;Do, Sei-Rok;Park, Deok-Yong
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.4
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    • pp.489-497
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    • 2011
  • Objectives : Based on data collected from patients who suffered from dental caries during the period between 1990 and 2008, the number of patients and their trends were analyzed as a source of evidence to conduct the oral health plan. Methods : A population of sample design for patient survey data was derived from computerized data saved at medical institutions accredited by National Health Insurance Corporation. Large institutions such as dental hospitals were included for the complete enumeration test, while the rest of medical institutions, for example, dental clinic, relatively small institutions, were used for the sample survey. Most of patients with dental caries were outpatients and their disease was treated at the dental hospital or dental clinic in general, therefore, main analysis was carried out at those institutions. Results : The rate of patients who suffered the dental caries has decreased to 56.8% in 2008 from 78.5% in 1990. The rate of patients who visited the dental hospital for treatment has increased to 4.8% in 2008 from 0.5% in 1990, whereas the percentage of those who visited the dental clinic has fallen to 97.9% from 99.5% during the same period. The ratio by age, in the meantime, it showed that patients aged 40s has increased to 13.5% in 2008 from 7.2% in 1990, and the number also has risen in 50s from 5.6% in 1990 to 9.9% in 2008. However, the number of children aged 0 to 9 who visited hospital for treatment of dental caries has fallen to 17.0% in 2008 from 33.9% in 1990. Conclusions : By figuring out the trends of patients with the dental caries during the period between 1990 and 2008, fundamental data for the oral health policy have been collected. As a result, the necessity of a new medical treatment system for managing the dental caries in terms of patient ages as well as the oral health policy and campaign was taken into consideration.

In situ ruminal degradation characteristics of dry matter and crude protein from dried corn, high-protein corn, and wheat distillers grains

  • Lee, Y.H.;Ahmadi, F.;Choi, D.Y.;Kwak, W.S.
    • Journal of Animal Science and Technology
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    • v.58 no.9
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    • pp.33.1-33.7
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    • 2016
  • Background: The continuing growth of the ethanol industry has generated large amounts of various distillers grains co-products. These are characterized by a wide variation in chemical composition and ruminal degradability. Therefore, their precise formulation in the ruminant diet requires the systematic evaluation of their degradation profiles in the rumen. Methods: Three distillers grains plus soluble co-products (DDGS) namely, corn DDGS, high-protein corn DDGS (HP-DDGS), and wheat DDGS, were subjected to an in situ trial to determine the degradation kinetics of the dry matter (DM) and crude protein (CP). Soybean meal (SBM), a feed with highly degradable protein in the rumen, was included as the fourth feed. The four feeds were incubated in duplicate at each time point in the rumen of three ruminally cannulated Hanwoo cattle for 1, 2, 4, 6, 8, 12, 24, and 48 h. Results: Wheat DDGS had the highest filterable and soluble A fraction of its DM (37.2 %), but the lowest degradable B (49.5 %; P < 0.001) and an undegradable C fraction (13.3 %; P < 0.001). The filterable and soluble A fraction of CP was greatest with wheat DDGS, intermediate with corn DDGS, and lowest with HP-DDGS and SBM; however, the undegradable C fraction of CP was the greatest with HP-DDGS (41.2 %), intermediate with corn DDGS (2.7 %), and lowest with wheat DDGS and SMB (average 4.3 %). The degradation rate of degradable B fraction ($%\;h^{-1}$) was ranked from highest to lowest as follows for 1) DM: SBM (13.3), wheat DDGS (9.1), and corn DDGS and HP-DDGS (average 5.2); 2) CP: SBM (17.6), wheat DDGS (11.6), and corn DDGS and HP-DDGS (average 4.4). The in situ effective degradability of CP, assuming a passage rate of $0.06h^{-1}$, was the highest (P < 0.001) for SBM (73.9 %) and wheat DDGS (71.2 %), intermediate for corn DDGS (42.5 %), and the lowest for HP-DDGS (28.6 %), which suggests that corn DDGS and HP-DDGS are a good source of undegraded intake protein for ruminants. Conclusions: This study provided a comparative estimate of ruminal DM and CP degradation characteristics for three DDGS co-products and SBM, which might be useful for their inclusion in the diet according to the ruminally undegraded to degraded intake protein ratio.

A Dynamic Recommendation System Using User Log Analysis and Document Similarity in Clusters (사용자 로그 분석과 클러스터 내의 문서 유사도를 이용한 동적 추천 시스템)

  • 김진수;김태용;최준혁;임기욱;이정현
    • Journal of KIISE:Software and Applications
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    • v.31 no.5
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    • pp.586-594
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    • 2004
  • Because web documents become creation and disappearance rapidly, users require the recommend system that offers users to browse the web document conveniently and correctly. One largely untapped source of knowledge about large data collections is contained in the cumulative experiences of individuals finding useful information in the collection. Recommendation systems attempt to extract such useful information by capturing and mining one or more measures of the usefulness of the data. The existing Information Filtering system has the shortcoming that it must have user's profile. And Collaborative Filtering system has the shortcoming that users have to rate each web document first and in high-quantity, low-quality environments, users may cover only a tiny percentage of documents available. And dynamic recommendation system using the user browsing pattern also provides users with unrelated web documents. This paper classifies these web documents using the similarity between the web documents under the web document type and extracts the user browsing sequential pattern DB using the users' session information based on the web server log file. When user approaches the web document, the proposed Dynamic recommendation system recommends Top N-associated web documents set that has high similarity between current web document and other web documents and recommends set that has sequential specificity using the extracted informations and users' session information.

Neighbor Caching for P2P Applications in MUlti-hop Wireless Ad Hoc Networks (멀티 홉 무선 애드혹 네트워크에서 P2P 응용을 위한 이웃 캐싱)

  • 조준호;오승택;김재명;이형호;이준원
    • Journal of KIISE:Information Networking
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    • v.30 no.5
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    • pp.631-640
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    • 2003
  • Because of multi-hop wireless communication, P2P applications in ad hoc networks suffer poor performance. We Propose neighbor caching strategy to overcome this shortcoming and show it is more efficient than self caching that nodes store data in theirs own cache individually. A node can extend its caching storage instantaneously with neighbor caching by borrowing the storage from idle neighbors, so overcome multi-hop wireless communications with data source long distance away from itself. We also present the ranking based prediction that selects the most appropriate neighbor which data can be stored in. The node that uses the ranking based prediction can select the neighbor that has high possibility to keep data for a long time and avoid caching the low ranked data. Therefore the ranking based prediction improves the throughput of neighbor caching. In the simulation results, we observe that neighbor caching has better performance, as large as network size, as long as idle time, and as small as cache size. We also show the ranking based prediction is an adaptive algorithm that adjusts times of data movement into the neighbor, so makes neighbor caching flexible according to the idleness of nodes

Direct Pass-Through based GPU Virtualization for Biologic Applications (바이오 응용을 위한 직접 통로 기반의 GPU 가상화)

  • Choi, Dong Hoon;Jo, Heeseung;Lee, Myungho
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.2
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    • pp.113-118
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    • 2013
  • The current GPU virtualization techniques incur large overheads when executing application programs mainly due to the fine-grain time-sharing scheduling of the GPU among multiple Virtual Machines (VMs). Besides, the current techniques lack of portability, because they include the APIs for the GPU computations in the VM monitor. In this paper, we propose a low overhead and high performance GPU virtualization approach on a heterogeneous HPC system based on the open-source Xen. Our proposed techniques are tailored to the bio applications. In our virtualization framework, we allow a VM to solely occupy a GPU once the VM is assigned a GPU instead of relying on the time-sharing the GPU. This improves the performance of the applications and the utilization of the GPUs. Our techniques also allow a direct pass-through to the GPU by using the IOMMU virtualization features embedded in the hardware for the high portability. Experimental studies using microbiology genome analysis applications show that our proposed techniques based on the direct pass-through significantly reduce the overheads compared with the previous Domain0 based approaches. Furthermore, our approach closely matches the performance for the applications to the bare machine or rather improves the performance.

WPS-based Satellite Image Processing onWeb Framework and Cloud Computing Environment (클라우드 컴퓨팅과 웹 프레임워크 환경에서 WPS 기반 위성영상 정보처리)

  • Yoon, Gooseon;Lee, Kiwon
    • Korean Journal of Remote Sensing
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    • v.31 no.6
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    • pp.561-570
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    • 2015
  • Till now, applications of many kinds of satellite images have been accentuated in the datacentric scientific studies, researches regarding system development and concerned technologies for them are on the un-matured stage. Especially, satellite image processing requires large volume data handling and specific analysis functionalities, so that practical necessity of base study for system development is emphasized on. In the view of information system, various edged trends such as web standards, cloud computing, or web framework are utilized owing to their application benefits proven and business needs. Considered these aspects, a testing implementation was carried out using OpenStack cloud computing environment and e-government framework. As for the processing functions, WPS in GeoServer, as one of OGC web standards, was applied to perform interoperable data processing scheme between two or more remote servers. Working with the server implemented, client-side was also developed using several open sources such as HTML 5, jQuery, and OpenLayers. If it is that completed further experiments onsite applications with actual multi-data sets and extension of on-demand functionalities with the result of this study, it will be referred as an example case model for complicated and complex system design and implementation which needs cloud computing, geo-spatial web standards and web framework.

A Study on Extending Successive Observation Coverage of MODIS Ocean Color Product (MODIS 해색 자료의 유효관측영역 확장에 대한 연구)

  • Park, Jeong-Won;Kim, Hyun-Cheol;Park, Kyungseok;Lee, Sangwhan
    • Korean Journal of Remote Sensing
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    • v.31 no.6
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    • pp.513-521
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    • 2015
  • In the processing of ocean color remote sensing data, spatio-temporal binning is crucial for securing effective observation area. The validity determination for given source data refers to the information in Level-2 flag. For minimizing the stray light contamination, NASA OBPG's standard algorithm suggests the use of large filtering window but it results in the loss of effective observation area. This study is aimed for quality improvement of ocean color remote sensing data by recovering/extending the portion of effective observation area. We analyzed the difference between MODIS/Aqua standard and modified product in terms of chlorophyll-a concentration, spatial and temporal coverage. The recovery fractions in Level-2 swath product, Level-3 daily composite product, 8-day composite product, and monthly composite product were $13.2({\pm}5.2)%$, $30.8({\pm}16.3)%$, $15.8({\pm}9.2)%$, and $6.0({\pm}5.6)%$, respectively. The mean difference between chlorophyll-a concentrations of two products was only 0.012%, which is smaller than the nominal precision of the geophysical parameter estimation. Increase in areal coverage also results in the increase in temporal density of multi-temporal dataset, and this processing gain was most effective in 8-day composite data. The proposed method can contribute for the quality enhancement of ocean color remote sensing data by improving not only the data productivity but also statistical stability from increased number of samples.

Reoperation for Hemorrhage Following Open Heart Surgery with Cardiopulmonary Bypass A Report of 81 cases (개심술후 출혈로 인한 응급 개흉술 81례의 임상적 고찰)

  • 오중환
    • Journal of Chest Surgery
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    • v.18 no.4
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    • pp.753-758
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    • 1985
  • Hemorrhage is an important complication after operation with cardiopulmonary bypass and sometimes necessitates a further emergency operation. Between July, 1962 and June, 1985, reoperation for hemorrhage was carried out on 81 patients [3.1%] out of a total 2634 patients who had previously undergone cardiopulmonary bypass surgery at the Department of Thoracic and Cardiovascular Surgery, Yonsei University Medical Center. There were 38 males and 43 females, with an average age of 25 years [ranging 6 months to 60 years] and an average body weight of 38 kg [ranging 5 to 77 kg].There were 43 patients of cyanotic heart disease, 32 patients of acquired valvular heart disease, 4 patients of coronary artery occlusive disease, 2 patients of ascending aorta aneurysm and annuloaortic ectasia. The average amount of blood loss in the case of cyanotic heart disease was 71.7140ml/kg, in acyanotic heart disease 45.16.3ml/kg, in acquired heart disease, 56.514.4ml/kg and in coronary artery occlusive disease, 50.618.7ml/kg during first post operative day. But there was no statistical difference [p>0.05]. The mean blood loss below 10 years old was 70.412.1 ml/kg. Those below 10 years old were believed to bleed more than any other group. But there was also no statistical difference [p>0.05]. Indications for reoperation were continued excessive blood loss [74%], cardiac tamponade or hypotension [23%] and radiological evidence of a large hematoma in the thorax and pericardium [2%]. Average bypass time was 2.10.1 hours [ranging 30 minutes to 5 hours]. The interval between operation and reoperation was as follows; less than 12 hours in 49 patients [60%], 12 to 24 hours in 20 patients [25%], 24 to 48 hours in 8 patients [10%], more than 48 hours in 4 patients [5%]. The commonest sites for bleeding were chest wall [36%], heart [34%], aorta [12%], pericardium [6%], thymus [5%] and others [6%]. But no definite source was found in ll patients [31%]. Twenty seven out of 81 patients [31%] had wound problems and 5 patients [6%] were expired. [Mean SEM]. In conclusion, in order to decrease the amount of blood loss after open heart surgery with cardiopulmonary bypass, shortening of bypass time and bleeding control at the wire suture site during chest wall closure were important. If the amount of blood loss was over 45 ml/kg or 8 m/kg/hour, reoperation should be considered as soon as possible. After operating, careful wound dressings were applied to prevent wound problems.

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