• Title/Summary/Keyword: stationary process

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Biodegradation of Kraft Lignins by White-Rot Fungi(I) -Lignin from Pitch Pine- (백색부후균에 의한 크라프트 리그닌의 분해(I) -리기다소나무 리그닌-)

  • 김명길;안원영
    • Journal of Korea Foresty Energy
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    • v.17 no.1
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    • pp.56-70
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    • 1998
  • This study was carried out to investigate the structural characteristics of kraft lignin and the wood degrading characteristics, the productivity of ligninolytic enzymes and the enzymatic degradation of kraft lignin by white-rot fungi. To purify kraft lignin, precipitation of kraft pulping black liquors of pitch pine meal was done by titration with lN $H_{2}SO_{4}$ reaching to pH 2, and isolation of the precipitates done by centrifugation. The isolated precipitates from pitch pine were redissloved in lN NaOH, reprecipitated by titration with lN $H_{2}SO_{4}$, washed with deionized water, and kept ofr analysis after freeze drying. Fractionation of the precipitates in solution by successive extraction with $CH_{2}Cl_{2}$ and MeOH, and the fractionates were named SwKL, SwKL I, SwKL II, and SwKL III for pitch pine kraft lignin. The more molecular weights of kraft lignin increased, the less phenolic hydroxyl groups and the more aliphatic hydroxyl groups. Because as the molecular weights increased, the ratio of etherified guaiayl/syringyl(G/S ratio) and the percentage were increased. The spectra obtained by 13C NMR and FTIR assigned by comparing the chemical shifts of various signals with shifts of signals from autherized ones reported. The optimal growth temperature and pH of white-rot fungi in medium were $28^{\circ}C$ and 4.5-5.0, respectively. Especially, in temperature and pH range, and mycelial growth, the best white-rot fungus selected was Phanerochaete chrysosporium for biodegradation. For the degradation pathways, the ligninolytic fungus jcultivated with stationary culture using medium of 1% kraft lignin as a substrate for 3 weeks at $28^{\circ}C$. The weight loss of pitch pine kraft lignin was 15.8%. The degraded products extracted successively methoanol, 90% dioxane and diethyl ether. The ether solubles were analyzed by HPLC. Kraft lignin degradation was initiated in $\beta$-O-4 bonds of lignin by the laccase from Phanerochaete chrysosporium and the degraded compounds were produced from the cleavage of $C\alpha$-$C\beta$ linkages at the side chains by oxidation process. After $C\alpha$-$C\beta$ cleavage, $C\alpha$-Carbon was oxidized and changed into aldehyde and acidic compounds such as syringic acid, syringic aldehyde and vanilline. And the other compound as quinonemethide, coumarin, was analyzed. The structural characteristics of kraft lignin were composed of guaiacyl group substituted functional OHs, methoxyl, and carbonyl at C-3, -4, and -5 and these groups were combinated with $\alpha$ aryl ether, $\beta$ aryl ether and biphenyl. Kraft lignin degradation pathways by Phanerochaete chrysosporium were initially accomplished cleavage of $C\alpha$-$C\beta$ linkages and $C\alpha$ oxidation at the propyl side chains and finally cleavage of aromatic ring and oxidation of OHs.

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South Korea's strategy to cope with local provocations by nuclear armed North Korea (핵위협하 국지도발 대비 대응전략 발전방향)

  • Kim, Tae-Woo
    • Strategy21
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    • s.31
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    • pp.57-84
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    • 2013
  • North Korea's continuous threats and provocative behaviors have aggravated tension on the Korean peninsula particularly with the recent nuclear weapons test. South Korea's best way to cope with this situation is to maintain the balance among three policy directions: dialogue, sanctions, and deterrence. Among the three, I argue that deterrence should be prioritized. There are different sources of deterrence such as military power, economic power, and diplomatic clouts. States can build deterrence capability independently. Alternatively, they may do so through relations with other states including alliances, bilateral relations, or multilateral relations in the international community. What South Korea needs most urgently is to maintain deterrence against North Korea's local provocations through the enhancement of independent military capability particularly by addressing the asymmetric vulnerability between militaries of the South and the North. Most of all, the South Korean government should recognize the seriousness of the negative consequences that North Korea's 'Nuclear shadow strategy' would bring about for the inter-Korea relations and security situations in Northeast Asia. Based on this understanding, it should develop an 'assertive deterrence strategy' that emphasizes 'multi-purpose, multi-stage, and tailored deterrence whose main idea lies in punitive retaliation.' This deterrence strategy requires a flexible targeting policy and a variety of retaliatory measures capable of taking out all targets in North Korea. At the same time, the force structures of the army, the air force, and the navy should be improved in a way that maximizes their deterrence capability. For example, the army should work on expanding the guided missile command and the special forces command and reforming the reserve forces. The navy and the air force should increase striking capabilities including air-to-ground, ship-to-ground, and submarine-to-ground strikes to a great extent. The marine corps can enhance its deterrence capability by changing the force structure from the stationary defense-oriented one that would have to suffer some degree of troop attrition at the early stage of hostilities to the one that focuses on 'counteroffensive landing operations.' The government should continue efforts for defense reform in order to obtain these capabilities while building the 'Korean-style triad system' that consists of advanced air, ground, and surface/ subsurface weapon systems. Besides these measures, South Korea should start to acquire a minimum level of nuclear potential within the legal boundary that the international law defines. For this, South Korea should withdraw from the Nuclear Non-proliferation Treaty. Moreover, it should obtain the right to process and enrich uranium through changing the U.S.-South Korea nuclear cooperation treaty. Whether or not we should be armed with nuclear weapons should not be understood in terms of "all or nothing." We should consider an 'in-between' option as the Japanese case proves. With regard to the wartime OPCON transition, we need to re-consider the timing of the transition as an effort to demonstrate the costliness of North Korea's provocative behaviors. If impossible, South Korea should take measures to make the Strategic Alliance 2015 serve as a persisting deterrence system against North Korea. As the last point, all the following governments of South Korea should keep in mind that continuing reconciliatory efforts should always be pursued along with other security policies toward North Korea.

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Ship s Maneuvering and Winch Control System with Voice Instruction Based Learning (음성지시에 의한 선박 조종 및 윈치 제어 시스템)

  • Seo, Ki-Yeol;Park, Gyei-Kark
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.6
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    • pp.517-523
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    • 2002
  • In this paper, we propose system that apply VIBL method to add speech recognition to LIBL method based on human s studying method to use natural language to steering system of ship, MERCS and winch appliances and use VIBL method to alternate process that linguistic instruction such as officer s steering instruction is achieved via ableman and control steering gear, MERCS and winch appliances. By specific method of study, ableman s suitable steering manufacturing model embodies intelligent steering gear controlling system that embody and language direction base studying method to present proper meaning element and evaluation rule to steering system of ship apply and respond more efficiently on voice instruction of commander using fuzzy inference rule. Also we embody system that recognize voice direction of commander and control MERCS and winch appliances. We embodied steering manufacturing model based on ableman s experience and presented rudder angle for intelligent steering system, compass bearing arrival time, evaluation rule to propose meaning element of stationary state and correct steerman manufacturing model rule using technique to recognize voice instruction of commander and change to text and fuzzy inference. Also we apply VIBL method to speech recognition ship control simulator and confirmed the effectiveness.

Structural Response Analysis of a Tension Leg Platform in Multi-directional Irregular Waves (다방향 불규칙파중의 인장계류식 해양구조물의 구조응답 해석)

  • Lee, Soo-Lyong;Suh, Kyu-Youl;Lee, Chang-Ho
    • Journal of Navigation and Port Research
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    • v.31 no.8
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    • pp.675-681
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    • 2007
  • A numerical procedure is described for estimating the effects of the multi-directional irregular waves on the structural responses of the Tension Leg Platform (TLP). The numerical approach is based on a three dimensional source distribution method for hydrodynamic forces, a three dimensional frame analysis method for structural responses, in which the superstructure of TLP is assumed to be flexible instead of rigid. Hydrodynamic and hydrostatic forces on the submerged surface of a TLP have been accurately calculated by excluding the assumption of the slender body theory. The hydrodynamic interactions among TLP members, such as columns and pontoons, and the structural damping are included in structural analysis. The spectral description used in spectral analysis of directional waves for the linear system of a TLP in the frequency domain is sufficient to completely define the structural responses. This is due to both the wave inputs and responses are stationary Gaussian random process of which the statistical properties in the amplitude domain are well known. The numerical results for the linear motion responses and tension variations in regular waves are compared with the experimental and numerical ones, which are obtained in Yoshida et al.(1983). The results of comparison confirmed the validity of the proposed approach.

Adaptive Query Flooding using Neighbor Information for Routing Performance Enhancement in Ad Hoc Networks (Ad Hoc Network에서 라우팅 성능 향상을 위한 이웃 노드 정보를 이용한 적응성 경로 구성 전송 방식)

  • Lee Hakhu;Kang Sangwook;An Sunshin
    • Journal of KIISE:Information Networking
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    • v.31 no.6
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    • pp.673-684
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    • 2004
  • As the wireless mobile communication is being widespread, mobile technologies will have important roles in the communication with the explosive growth of demanding for wireless portable devices. Among the mobile technologies, a great deal of interest has been taken in mobile ad hoc network (MANET), which is a collection of wireless mobile nodes forming a temporary network without the aid of stationary infrastructure in recent. Furthermore, considering characteristic of ad hoc networks, the design of efficient routing protocols is an important issue. In recent years, on-demand protocols among routing protocols have noticed because of the low routing overhead. However, on-demand protocols suffer from production of the enormous query Packets by broadcasting in order to setup routes, that is, a flooding scheme. The flooding scheme is very costly and results in serious problem, which we refer as the broadcast storm problem. In this paper, we propose a Dynamic Adaptation Query flooding Using Neighbor Topology (NT-DAQ) scheme, in order to resolve the broadcast storm Problem. When a route discovery is in progress, each mobile node decides on the basis of neighbor topology information whether discovery process participates or not. Therefore, our proposed scheme enables to improve network performance in which minimize the number of query rackets. We evaluate the efficiency of our proposed scheme through simulation.

The Development of Real-time Video Associated Data Service System for T-DMB (T-DMB 실시간 비디오 부가데이터 서비스 시스템 개발)

  • Kim Sang-Hun;Kwak Chun-Sub;Kim Man-Sik
    • Journal of Broadcast Engineering
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    • v.10 no.4 s.29
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    • pp.474-487
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    • 2005
  • T-DMB (Terrestrial-Digital Multimedia Broadcasting) adopted MPEG-4 BIFS (Binary Format for Scene) Core2D scene description profile and graphics profile as the standard of video associated data service. By using BIFS, we can support to overlay objects, i.e. text, stationary image, circle, polygon, etc., on the main display of receiving end according to the properties designated in broadcasting side and to make clickable buttons and website links on desired objects. Therefore, a variety of interactive data services can be served by BIFS. In this paper, we implement real-time video associated data service system far T-DMB. Our developing system places emphasis on real-time data service by user operation and on inter-working and stability with our previously developed video encoder. Our system consists of BIFS Real-time System, Automatic Stream Control System and Receiving Monitoring System. Basic functions of our system are designed to reflect T-DMB programs and characteristics of program production environment as a top priority. Our developed system was used in BIFS trial service via KBS T-DMB, it is supposed to be used in T-DMB main service after improvement process such as intensifying system stability.

Analysis of the Mental Images in Episodic Memory with Comparison between the patients with Dementia of Alzheimer Type and Healthy Elderly People (알츠하이머성 치매환자와 건강한 노인의 일화기억 이미지 비교 분석)

  • Han, Kyung-Hun;Ernst, Poppel
    • Korean Journal of Cognitive Science
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    • v.20 no.1
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    • pp.79-107
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    • 2009
  • Episodic memory, i.e. memorization of information within a spatiotemporal environment, is affected Alzheimer's disease(AD), but its impairment may also be occurred in the normal aging process. The purpose of this study is to analyze and evaluate memory in with Dementia of Alzheimer Type by examining their cognitive skills in episodic memory using the technique. This new method involves assessing the mental images the subject's own past in the mind like projected and movies. Three patients in the early stage of Dementia of Alzheimer Type, one with mild depression, and 2 healthy controls for comparison were asked to retrieve their episodic memory of the previous day, week, month, and a day testing day. The answers were then analyzed with regards to their specific features as emotional state, color, and time order. In the following day, the subjects were tasked to recall again the images they reproduced in the day's test order to observe of memory. Results showed that all 3 patients failed to arrange the retrieved images in time order and their images of the previous day were unclear in color and were stationary like photographs, even when they reproduced the mental images at much quantity as controls. patients could not remember particular events of yesterday, and only recalled the general occurrences of every day life. These results suggest that in the early stage of Dementia of Alzheimer Type, difficulties in the retrieval of recent episodic memory begin to primarily occur, and qualitative impairment happens earlier than quantitative.

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A Study on the Distribution and Composition of Floating Debris in the Coast of Korea II. Transport of Debris in Middle Part of Southern Sea (연안어장의 부유성 폐기물 분포와 조성에 관한 연구 II. 남해 중부해역의 폐기물 수송)

  • KIM Jong-Hwa
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.3
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    • pp.338-344
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    • 1999
  • Floating debris was recorded from a training ship, $\sharp$1 Kwanaksan, of Pukyong National University with about 10 knots speed at July 15th and 20th of 1997. The sampled area is the middle of southern sea of Korea, divided into 44 unit segments on survey routes. Debris fabrication materials were categorized with 6 items using the following; man-made or natural wood items, paper and cardboard, nylon netting and rope, styrofoam, plastics, floating metal and glass containers. All identified items within a 100 $\pm$ 2 m wide band were recorded but ignored if beyond this boundary. The results of distribution and transport of floating debris in the area are as follows: 1. The quantities of debris during the survey were distributed from $1.6\~369.7\;items/km^2$. The most obvious trend is the widespread distribution of all debris. The highest densities of all debris were discovered in the coastal waters of Namhae and Yokji island, and of about 50 km off from the southward of Yokji and about 74 km off from the eastward of Komun island. Especially many of small styrofoams within $\phi$20 cm were observed in these segments. 2. Styrofoams and plastics were composed of $83.5\%$ among all debris, next woods items, $9.8\%$. 3. The quantities, distribution shapes and composition of debris were varied as the observed duration and the natures of each items. 4. These phenomena are concluded that firstly they depend on the river discharges included debris due to precipitation falls, secondly inflow or dumping debris are drifting to the off-shore by Kuroshio currents present at their adjacent sea, But on the basis of the observed data it is difficult that source position, quantities and inflow items of debris are identified, and also the transport processes is pursue. further more surveys are continuously being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps on all sites of the Coast of Korea and contributed to the stationary area, finding of sources, removal method of debris and resistants of marine productivity.

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Video object segmentation using a novel object boundary linking (새로운 객체 외곽선 연결 방법을 사용한 비디오 객체 분할)

  • Lee Ho-Suk
    • The KIPS Transactions:PartB
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    • v.13B no.3 s.106
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    • pp.255-274
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    • 2006
  • Moving object boundary is very important for the accurate segmentation of moving object. We extract the moving object boundary from the moving object edge. But the object boundary shows broken boundaries so we develop a novel boundary linking algorithm to link the broken boundaries. The boundary linking algorithm forms a quadrant around the terminating pixel in the broken boundaries and searches for other terminating pixels to link in concentric circles clockwise within a search radius in the forward direction. The boundary linking algorithm guarantees the shortest distance linking. We register the background from the image sequence using the stationary background filtering. We construct two object masks, one object mask from the boundary linking and the other object mask from the initial moving object, and use these two complementary object masks to segment the moving objects. The main contribution of the proposed algorithms is the development of the novel object boundary linking algorithm for the accurate segmentation. We achieve the accurate segmentation of moving object, the segmentation of multiple moving objects, the segmentation of the object which has a hole within the object, the segmentation of thin objects, and the segmentation of moving objects in the complex background using the novel object boundary linking and the background automatically. We experiment the algorithms using standard MPEG-4 test video sequences and real video sequences of indoor and outdoor environments. The proposed algorithms are efficient and can process 70.20 QCIF frames per second and 19.7 CIF frames per second on the average on a Pentium-IV 3.4GHz personal computer for real-time object-based processing.

A Dynamic Analysis of PSC Box Bridge Varying Span Lengths for Increased Speeds of KTX (고속철 속도변화에 대한 PSC박스 교량의 경간길이 별 동적해석)

  • Oh, Soon Taek;Lee, Dong Jun;Shim, Young Woo;Yun, Jun Kwan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.4
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    • pp.204-211
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    • 2011
  • A dynamic analysis procedure is developed to provide a better estimation of the dynamic responses of bridge during the passage of high speed railway vehicles. Particularly, a three dimensional numerical model including the structural interaction between high speed vehicles, bridges and railway endures to analyse accurately and evaluate with in-depth parametric studies for dynamic responses of various bridge span lengths running KTX railway locomotive up to increasing maximum speed(450km/h). Three dimensional frame element is used to model the simply supported pre-stressed concrete (PSC) box bridges for four span lengths(40~25m). Track irregularity employed as a stationary random process from the given spectral density functions and irregularities of both sides of the track are assumed to have high correlation. The high-speed railway vehicle (KTX) is used as 38-degree of freedom system. Three displacements (Vertical, lateral, and longitudinal) as well as three rotational components (Pitching, rolling, and yawing) are considered in the 38-degree of freedom model. The dynamic amplification factors are evaluated by the developed procedure under various traveling conditions, such as track irregularity camber, train speed and ballast. The dynamic analysis such as Newmark-${\beta}$ and Runge-Kutta methods which are able to analyse considering the dynamic impact factors are compared and contrasted.