• Title/Summary/Keyword: adaptive method

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4-Dimensional dose evaluation using deformable image registration in respiratory gated radiotherapy for lung cancer (폐암의 호흡동조방사선치료 시 변형영상정합을 이용한 4차원 선량평가)

  • Um, Ki Cheon;Yoo, Soon Mi;Yoon, In Ha;Back, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.83-95
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    • 2018
  • Purpose : After planning the Respiratory Gated Radiotherapy for Lung cancer, the movement and volume change of sparing normal structures nearby target are not often considered during dose evaluation. This study carried out 4-D dose evaluation which reflects the movement of normal structures at certain phase of Respiratory Gated Radiotherapy, by using Deformable Image Registration that is well used for Adaptive Radiotherapy. Moreover, the study discussed the need of analysis and established some recommendations, regarding the normal structures's movement and volume change due to Patient's breathing pattern during evaluation of treatment plans. Materials and methods : The subjects were taken from 10 lung cancer patients who received Respiratory Gated Radiotherapy. Using Eclipse(Ver 13.6 Varian, USA), the structures seen in the top phase of CT image was equally set via Propagation or Segmentation Wizard menu, and the structure's movement and volume were analyzed by Center-to Center method. Also, image from each phase and the dose distribution were deformed into top phase CT image, for 4-dimensional dose evaluation, via VELOCITY Program. Also, Using $QUASAR^{TM}$ Phantom(Modus Medical Devices) and $GAFCHROMIC^{TM}$ EBT3 Film(Ashland, USA), verification carried out 4-D dose distribution for 4-D gamma pass rate. Result : The movement of the Inspiration and expiration phase was the most significant in axial direction of right lung, as $0.989{\pm}0.34cm$, and was the least significant in lateral direction of spinal cord, as -0.001 cm. The volume of right lung showed the greatest rate of change as 33.5 %. The maximal and minimal difference in PTV Conformity Index and Homogeneity Index between 3-dimensional dose evaluation and 4-dimensional dose evaluation, was 0.076, 0.021 and 0.011, 0.0 respectfully. The difference of 0.0045~2.76 % was determined in normal structures, using 4-D dose evaluation. 4-D gamma pass rate of every patients passed reference of 95 % gamma pass rate. Conclusion : PTV Conformity Index was more significant in all patients using 4-D dose evaluation, but no significant difference was observed between two dose evaluations for Homogeneity Index. 4-D dose distribution was shown more homogeneous dose compared to 3D dose distribution, by considering the movement from breathing which helps to fill out the PTV margin area. There was difference of 0.004~2.76 % in 4D evaluation of normal structure, and there was significant difference between two evaluation methods in all normal structures, except spinal cord. This study shows that normal structures could be underestimated by 3-D dose evaluation. Therefore, 4-D dose evaluation with Deformable Image Registration will be considered when the dose change is expected in normal structures due to patient's breathing pattern. 4-D dose evaluation with Deformable Image Registration is considered to be a more realistic dose evaluation method by reflecting the movement of normal structures from patient's breathing pattern.

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Influence of substituted phenylcarbamoyl group on the fungicidal activites of a new 5,6-dihydro-2-trifluoromethyl-1,4-oxathiincarboxanilide derivatives (새로운 5,6-dihydro-2-trifluoromethyl-1,4-oxathiincarboxanilide 유도체의 항균활성에 미치는 치환-phenylcarbamoyl group의 영향)

  • Sung, Nack-Do;Yu, Seong-Jae;Nam, Kee-Dal;Chang, Kee-Hyuk;Hahn, Hoh-Gyu
    • The Korean Journal of Pesticide Science
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    • v.2 no.3
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    • pp.64-69
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    • 1998
  • New thirty derivatives of 5,6-dihydro-2-trifluoromethyl-1,4-oxathiin carboxanilide as substrate(S) were synthesized and their fungicidal activities in vivo against rice sheath blight(Rhizoctonia solani) and wheat leaf rust(Puccinia recondita) were examined. The structure activity relationships(SAR) between the activities($pI_{50}$) and a physicochemical parameters of substituents(X) at the phenylcarbamoyl group were analyzed using the adaptive regression analysis method. The 3-methoxy, 11, 3-isopropyloxy, 13 and 3-isopropyl substituent, 25 as X on the phenylcarbamoyl group exhibited the most highest fungicidal activity against the two fungi. The fungicidal potency of the (S) against Puccinia recondita was higher than Rhizoctonia solani. In case of Rhizoctonia solani, the molecular hydrophobicity(${\pi}>0$) and resonance effect(R<0) by meta-alkyl substitutents with electron donating were important factors in determining fungicidal activity. And the HOMO energy(HOMO>0), ABSQ, sum of absolute values of the atomic charges on each atom and specific polarizability(Sp.Pol<0) of (S) were significantly influential towards fungicidal activity against Puccinia recondita.. The interaction between (S) and receptor agonist from the based on SAR studies proceeds through charge-control reaction, and conditions to show higher activity has been also discussed.

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A Queriable XML Compression using Inferred Data Types (추론한 데이타 타입을 이용한 질의 가능 XML 압축)

  • ;;Chung Chin-Wan
    • Journal of KIISE:Databases
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    • v.32 no.4
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    • pp.441-451
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    • 2005
  • HTML is mostly stored in native file systems instead of specialized repositories such as a database. Like HTML, XML, the standard for the exchange and the representation of data in the Internet, is mostly resident on native file systems. However. since XML data is irregular and verbose, the disk space and the network bandwidth are wasted compared to those of regularly structured data. To overcome this inefficiency of XML data, the research on the compression of XML data has been conducted. Among recently proposed XML compression techniques, some techniques do not support querying compressed data, while other techniques which support querying compressed data blindly encode data values using predefined encoding methods without considering the types of data values which necessitates partial decompression for processing range queries. As a result, the query performance on compressed XML data is degraded. Thus, this research proposes an XML compression technique which supports direct and efficient evaluations of queries on compressed XML data. This XML compression technique adopts an encoding method, called dictionary encoding, to encode each tag of XML data and applies proper encoding methods for encoding data values according to the inferred types of data values. Also, through the implementation and the performance evaluation of the XML compression technique proposed in this research, it is shown that the implemented XML compressor efficiently compresses real-life XML data lets and achieves significant improvements on query performance for compressed XML data.

A Modification of The Fuzzy Logic Based DASH Adaptation Algorithm for Performance Improvement (성능 향상을 위한 퍼지 논리 기반 DASH 알고리즘의 수정)

  • Kim, Hyun-Jun;Son, Ye-Seul;Kim, Joon-Tae
    • Journal of Broadcast Engineering
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    • v.22 no.5
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    • pp.618-631
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    • 2017
  • In this paper, we propose a modification of fuzzy logic based DASH adaptation algorithm(FDASH) for seamless media service in time-varying network conditions. The proposed algorithm selects more appropriate bit-rate for the next segment by the modification of the Fuzzy Logic Controller(FLC) and reduces the number of video bit-rate changes by applying Segment Bit-rate Filtering Module(SBFM). Also, we apply the Start Mechanism for clients not to watch the low quality videos in the very beginning stage of streaming service and add the Sleeping Mechanism to avoid any buffer overflow expected. Ultimately, we verified by using NS-3 Network Simulator that the proposed method shows better performance compared to FDASH. According to the experimental results, there is no buffer underflow/overflow within the limited buffer size, which is not guaranteed in FDASH on the other hand. Also, we confirmed that mFDASH has almost the same level of average video quality against FDASH and reduces about 50% of number of video bit-rate changes compared to FDASH in Point-to-Point network and Wi-Fi network.

Development of a Laser-Generated Ultrasonic Inspection System by Using Adaptive Error Correction and Dynamic Stabilizer (적응적 에러 보정과 다이나믹 안정기를 이용한 레이저 유도 초음파 검사 시스템 개발)

  • Park, Seung-Kyu;Baik, Sung-Hoon;Park, Moon-Cheol;Lim, Chang-Hwan;Ra, Sung-Woong
    • Journal of the Korean Society for Nondestructive Testing
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    • v.25 no.5
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    • pp.391-399
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    • 2005
  • Laser-generated ultrasonic inspection system is a non-contact scanning inspection device with high spatial resolution and wide bandwidth. The amplitude of laser-generated ultrasound is varied according to the energy of pulse laser and the surface conditions of an object where the CW measuring laser beam is pointing. In this paper, we correct the generating errors by measuring the energy of pulse laser beam and correct the measuring errors by extracting the gain information of laser interferometer at each time. h dynamic stabilizer is developed to stably scan on the surface of an object for an laser-generated ultrasonic inspection system. The developed system generates ultrasound after adaptively finding the maximum gain time of an laser interferometer and processes the signal in real time after digitization with high speed. In this paper, we describe hardware configuration and control algorithm to build a stable laser-generated ultrasonic inspection system. Also, we confirmed through experiments that the proposed correction method for the generating errors and measuring errors is effective to improve the performance of a system.

Selection of an Optimal Conception Design for the Development of Noise-reduced System Aluminum Form (소음저감형 시스템 알루미늄 거푸집의 최적 개념디자인 선정)

  • Hong, Jong Hyun;Yeom, Dong Jun;Kim, Young Suk
    • Korean Journal of Construction Engineering and Management
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    • v.17 no.2
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    • pp.135-145
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    • 2016
  • In Korea, a series of noise-reduced aluminum forms are being recently used in apartment housing construction. However, their complicated and time-consuming work processes, and the noise which is still generated due to the inherent property of aluminum when especially installing and dismantling them have been pointed out as a problem to be certainly solved for increasing their practical use in construction sites. The primary objectives of this study are proposing an optimal conceptual design of a newly designed noise-reduced aluminum form and verifying the technical feasibility by conducting a working mock-up drive experiment. Thus, conventional noise-reduced aluminum forms have been analyzed and three conceptual designs of a newly noise-reduced aluminum forms have been deducted. AHP has been applied to a survey data collected by interviewing field experts. A trade-off analysis results have shown that 'Noise-reduced System Aluminum Form with a Drop-down Floor Post and Adaptive Beam' the highest weights of safety(0.52), work convenience(0.54) and thus selected. The suggested conceptual design in this study improved problems of conventional system aluminum forms. It is also expected that the suggested design will be used as a reliable guideline for the actual development of an aluminum form that ensures noise-reduce, work convenience and labor safety.

Denver II Developmental Screening Test: A Cross Cultural Comparison (Denver II 발달검사를 이용한 한국과 미국의 아동 발달 비교 연구)

  • Shin, Hee-Sun;Han, Kyung-Ja;Oh, Ka-Sil;Oh, Jin-Joo;Ha, Mi-Na
    • Research in Community and Public Health Nursing
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    • v.13 no.1
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    • pp.89-97
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    • 2002
  • Purpose: The purpose of this study is to explore the validity of the application of the Denver II developmental screening test to Korean children. This screening test. which was developed and standardized in United States. was designed to screen for developmental delay in Korea. and to compare the levels of development of Korean children with the development of children from the U.S. Method: Quota sampling. NP To facilitate field sampling. the age range used from 0 to 6 years old. was split into 10 different age groups. Sample size was estimated according to residence. 1.054 children were recruited from Seoul's metropolitan. urban and rural areas. NP To fill the quota established. the Recruitment and testing of children was done at public health centers, pediatric outpatient clinics of general hospitals and a child care center. The 25, 50, 75 and 90 percentiles were identified by using logistic regression analysis and were calculated as norms. The items in which the ages of both 50 and 90 percent passing differed more than 20 percent by the calculation was identified for comparison. NP Result: There were significant differences found in 45 items between Korean children and the children from the City of Denver as it relates to age differences. 90% of the sample passed items among 125 items from 4 sectors, e.g., personal- social. fine motor adaptive, language, and gross motor sectors. Korean children were found to be advanced in 9 items, whereas there were significant differences found in 38 items in our comparison of the two countries for age differences when 50% of sample pass items. Korean children were found to be advanced in 16 items. NP Conclusion: The result showed that there was a discrepancy in the developmental norms. It could be explained by the differences in the developmental environment. including child rearing patterns and ethnicity. Therefore, a restandardization of the Denver Screening Test is necessary as it relates to its application on Korean children. This restandardization is necessary in order to avoid both under and over-referrals of children with developmental abnormality. The modification of items in the language sector is especially suggested.

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Channel Variation Tracking based Effective Preferred BS Selection Scheme of Idle Mode Mobile device for Mobile WiMAX System (Mobile WiMAX시스템에서 채널품질 변동추적을 이용한 유휴모드 이동단말의 효율적인 선호기지국 선택 방안)

  • Lee, Kang-Gyu;Youn, Hee-Yong
    • The KIPS Transactions:PartC
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    • v.17C no.6
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    • pp.471-484
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    • 2010
  • In the wireless communication systems, the power consumption of a mobile device is very important issue due to its battery limitations. Hence most of the standards for wireless networks including a mobile WiMAX system are supporting their own power saving mode in way that a mobile device is able to reduce its energy usage while in the mode. However, those standards just define the arrangement of special time intervals, called a paging listening interval, during which the device needs to receive the paging-related control messages, and they do not specify how to effectively reduce the power in many different network environments. This means the amount of power spent by the device is very dependent on the implementations of individual device-vendors, and undesirable paging loss may happen according to the channel conditions. To reduce unnecessary power usage and the risk of paging loss, this paper proposes the effective frequency/BS selection algorithm applicable to a mobile device operating in the power saving mode, which serves the device with better BS based on the tracking for channel variation. This algorithm consists of the channel estimation phase during each paging listening interval, the tracking phase for the measured results, the frequency reselection phase based on the tracking activity, and the preferred BS reselection phase. Thus the proposed method can improve the paging performance while the device is moving in the network. Also the simulation result shows that the presented scheme is superior to other candidates in energy efficiency due to the channel-adaptive frequency/BS selection.

A study of Vertical Handover between LTE and Wireless LAN Systems using Adaptive Fuzzy Logic Control and Policy based Multiple Criteria Decision Making Method (LTE/WLAN 이종망 환경에서 퍼지제어와 정책적 다기준 의사결정법을 이용한 적응적 VHO 방안 연구)

  • Lee, In-Hwan;Kim, Tae-Sub;Cho, Sung-Ho
    • The KIPS Transactions:PartC
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    • v.17C no.3
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    • pp.271-280
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    • 2010
  • For the next generation mobile communication system, diverse wireless network techniques such as beyond 3G LTE, WiMAX/WiBro, and next generation WLAN etc. are proceeding to the form integrated into the All-IP core network. According to this development, Beyond 3G integrated into heterogeneous wireless access technologies must support the vertical handover and network to be used of several radio networks. However, unified management of each network is demanded since it is individually serviced. Therefore, in order to solve this problem this study is introducing the theory of Common Radio Resource Management (CRRM) based on Generic Link Layer (GLL). This study designs the structure and functions to support the vertical handover and propose the vertical handover algorithm of which policy-based and MCDM are composed between LTE and WLAN systems using GLL. Finally, simulation results are presented to show the improved performance over the data throughput, handover success rate, the system service cost and handover attempt number.

Automatic Prostate Segmentation in MR Images based on Active Shape Model Using Intensity Distribution and Gradient Information (MR 영상에서 밝기값 분포 및 기울기 정보를 이용한 활성형상모델 기반 전립선 자동 분할)

  • Jang, Yu-Jin;Hong, Helen
    • Journal of KIISE:Software and Applications
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    • v.37 no.2
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    • pp.110-119
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    • 2010
  • In this paper, we propose an automatic segmentation of the prostate using intensity distribution and gradient information in MR images. First, active shape model using adaptive intensity profile and multi-resolution technique is used to extract the prostate surface. Second, hole elimination using geometric information is performed to prevent the hole from occurring by converging the surface shape to the local optima. Third, the surface shape with large anatomical variation is corrected by using 2D gradient information. In this case, the corrected surface shape is often represented as rugged shape which is generated by the limited number of vertices. Thus, it is reconstructed by using surface modelling and smoothing. To evaluate our method, we performed the visual inspection, accuracy measures and processing time. For accuracy evaluation, the average distance difference and the overlapping volume ratio between automatic segmentation and manual segmentation by two radiologists are calculated. Experimental results show that the average distance difference was 0.3${\pm}$0.21mm and the overlapping volume ratio was 96.31${\pm}$2.71%. The total processing time of twenty patient data was 16 seconds on average.