• Title/Summary/Keyword: phase adjustment

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A Method for Minimizing the Number of Clusters in Ad-Hoc Networks (Ad-Hoc 네트워크에서 클러스터 수를 최소화하기 위한 방안)

  • Bang Sang-Won
    • Journal of Internet Computing and Services
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    • v.5 no.6
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    • pp.21-30
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    • 2004
  • In Ad-Hoc network, the cluster structure enables effective use of multiple channels, reduces the number of control messages, and increase the scalability of network, Also, it is employed for reducing the number of broadcast messages in an Ad-Hoc network. With the consideration of these advantages, it is desirable that a cluster structure keeps a few clusters in the network, Generally, the cluster formation scheme based on connectivity yields fewer clusters than the other schemes. However, the connectivity based scheme may yield even more clusters than the other schemes according to the network topology. In this paper, a cluster formation scheme dividing the cluster formation into two phases is proposed. In the first phase, the lowest connectivity host in neighborhood initiates the cluster formation. Then, an adjustment procedure for affiliating a lot of the lowest connectivity hosts is employed. In the second phase, the hosts which were not affiliated to the first phase clusters are grouped into one or more clusters through criterions of connectivity and host ID. As a result, the proposed scheme yields a fewer clusters compared with existing other schemes in fully distributed method. The simulation results proves that our scheme is better than LIDCP(3) and HCCP(3).

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Speckle Noise Reduction and Image Quality Improvement in U-net-based Phase Holograms in BL-ASM (BL-ASM에서 U-net 기반 위상 홀로그램의 스펙클 노이즈 감소와 이미지 품질 향상)

  • Oh-Seung Nam;Ki-Chul Kwon;Jong-Rae Jeong;Kwon-Yeon Lee;Nam Kim
    • Korean Journal of Optics and Photonics
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    • v.34 no.5
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    • pp.192-201
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    • 2023
  • The band-limited angular spectrum method (BL-ASM) causes aliasing errors due to spatial frequency control problems. In this paper, a sampling interval adjustment technique for phase holograms and a technique for reducing speckle noise and improving image quality using a deep-learningbased U-net model are proposed. With the proposed technique, speckle noise is reduced by first calculating the sampling factor and controlling the spatial frequency by adjusting the sampling interval so that aliasing errors can be removed in a wide range of propagation. The next step is to improve the quality of the reconstructed image by learning the phase hologram to which the deep learning model is applied. In the S/W simulation of various sample images, it was confirmed that the peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) were improved by 5% and 0.14% on average, compared with the existing BL-ASM.

A Study on the Installation of Rupture Disk for Emergency Discharge of Dangerous Substances in Case of Styrene Monomer Runaway Reaction (스티렌모노머 폭주반응 시 위험물 비상 배출을 위한 파열판 적정 크기 선정에 관한 연구)

  • Sang Ryung Kim;Jae Min Ryu;Hyang Nam Choi;Jong Su Hyun;Hyung Sik Byun
    • Journal of the Korean Institute of Gas
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    • v.28 no.2
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    • pp.24-31
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    • 2024
  • In the chemical industry, fires and explosions constantly occur due to runaway reactions during the production of various chemical products. To prevent this, much research has been conducted, and the possibility of runaway reactions for each substance is reviewed and interlocking devices are installed to prepare for adverse reactions to prepare for fires and explosions. However, despite legal and technical safety measures, accidents due to runaway reactions still occur every year. Accordingly, in this study, based on cases of fire and explosion accidents in styrene monomer reactors, the discharge capacity during runaway reactions was examined through experiments and graphs. Unlike the commonly calculated fire equation, in the case of a runaway reaction where pressure and temperature increase rapidly, discharge is made in two phases rather than a single phase, so the size of the rupture disk must also increase, and the orientation must be adjusted before the rupture disk is installed at the top of the pressure vessel. It was found that position adjustment was necessary.

A Study for Developing Music Therapy Activity Program for Development of Rudimentary Movement Phase of Spastic Cerebral Palsied Infant : Applying the techniques of Neurological Music Therapy (경직형 뇌성마비 유아의 초보운동단계 발달을 위한 음악치료활동 프로그램 개발 - 신경학적 음악치료의 기법을 활용하여)

  • Lee, Yoon Jin
    • Journal of Music and Human Behavior
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    • v.4 no.2
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    • pp.84-105
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    • 2007
  • Cerebral palsy is a collection of motor disorders resulting from damage to the central nervous system that arise in multiple handicaps including cognitive disorders, speech disorders, epilepsy, perception disorders, and emotion disorders. Today spastic cerebral palsy has become more prevalent because intensive care for newborns has resulted in higher survival rates for very small premature babies. Since the children grow the fastest in order for a development during one year after birth, the therapeutic intervention is provided as early as possible to the children with cerebral palsy. After seven year old, there is no effect of intervention. So, the necessity of early intervention to spastic cerebral palsied infants is increasing. The purpose of this study is to develop the music therapy activity program using the techniques of neurological music therapy(NMT), the therapeutic application of music to dysfunctions due to neurologic disease of the human nervous system, for rudimentary movement phase of spastic cerebral palsied infant. This music therapy activity program was developed on the basis of the major developmental tasks of the rudimentary movement phase, the period that children can acquire the most basic movement function at the 0 to 2. Then the developmental characteristics of spastic cerebral palsy were applied to this music therapy activity program. This music therapy activity program was classified to three domains, those are stability, locomotion, and manipulation. This study has been consisted of three steps, those are the development of the activities, the evaluation of the activities by th panels, and the adjustment and complement of the activities. Reviewing literatures and interviews were done for the development of the activities, and the evaluation the activities was done by seven music therapists. In the evaluation steps, the questionnaire was used for estimating the content validity and application efficiency. The adjustment and complement of the activities were evaluated by the panels who were participating in the music therapy for cerebral palsied children in the clinical setting, and the results of the adjustment and complement were confirmed by the panels. The evaluation was presented in a mean value with the comment of the panels. In conclusion, the music therapy activity program for the spastic cerebral palsied infants using the techniques of NMT was developed on the basis of the major developmental tasks of the rudimentary movement phase. The program is comprised of 38 activities, those are 14 activities for developing the stability, 10 activities for developing the locomotion, and 14 activities for developing the manipulation. The programed activities would bring out the answers in the affirmative for the conformance with infants' development phase, the harmony between the objective and the activity, the conformance with the cerebral palsied infants, the properness of the music and the instruments, and the utility in the clinic field. This results mean that this developed music activity program is appropriate to help spastic cerebral palsied infants progress their movement development by stages.

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Monitoring the Reproductive Status of Dairy Cows by Urinary Pregnanediol Glucuronide

  • Yang, C.J.;Wu, L.S.;Liu, S.H.;Lin, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.4
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    • pp.460-466
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    • 2004
  • This study was undertaken with the aim to establish a reliable radioimmunoassay (RIA) system for urinary pregnanediol glucuronide (PdG) and to employ it for monitoring the reproductive status of dairy cows. Urine and blood samples were collected from the Holstein cows both pregnant and non-pregnant. The samples were then investigated for evaluating the relationship between progesterone ($P_{4}$) in blood and PdG in urine adjusted with or without urinary creatinine basis. Biweekly urine collection was employed for three cows in estrous and those artificially inseminated, while urine from pregnant cows was collected on a monthly basis. P_{4}$ and PdG levels were measured by enzymeimmunoassay (EIA) and RIA techniques, respectively. Our results indicated the sensitivity of PdG for RIA being 35 pg/tube and the recovery rate of 100%. Urinary creatinine concentrations also fluctuated within a day, but change at midday was not noteworthy. Regardless of the time of urination the change in concentrations of PdG was relatively smaller and did not vary significantly. The urinary PdG concentration showed periodic changes as that with serum P_{4}$ levels during the cow's estrus cycle. The correlation coefficient rose when creatinine level in urine was adjusted but the change was also not significant. The concentrations of PdG during the luteal phase were detected between 8.2 and 17.4 ng/ml, three to five times higher than that in the follicular phase. The concentration of PdG from pregnant cows (21 days after conception) was three to four times higher than in the nonpregnant cows. Our finding suggests that the determination of urinary PdG could be reliably employed for early pregnancy detection. The urinary PdG level continued to raise until 30 days pre-partum while the concentration reached its peak at 30 ng/ml, after which it started to fall 18 to 30 days before parturition and finally fell to its nadir value one week after parturition. As the correlation coefficient between the urinary PdG and serum P_{4}$ was higher than that corrected by urinary creatinine it can be suggested that the adjustment is not needed. The concentrations of urinary PdG could be maintained stably for 2 days in urine samples stored at room temperature and extended to 8 days when the samples were pretreated by boiling for 30 minutes. In conclusion urinary PdG concentration even without the need for creatinine basis adjustment can be used directly for monitoring the reproductive status of dairy cows.

The Influence of Innovative SME CEO Types on Technology Innovation Capabilities and Innovation Performance (혁신형 중소기업의 CEO유형에 따른 기술혁신 역량이 기술혁신 성과에 미치는 영향)

  • Kim, Ji-Hun
    • The Journal of the Korea Contents Association
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    • v.19 no.12
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    • pp.215-228
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    • 2019
  • This study micro-analyzed the impact of innovation capabilities on innovation performance by type of CEO, with innovative SMEs being subject to research. In addition, the impact of CEO type on innovative capabilities and the impact of innovative capabilities on innovation performance were studied together. In order to achieve the research objective, we conducted an empirical analysis of 250 innovative small and medium-sized enterprises registered in the medium-term department as research targets and the results are as follows. First, the analysis of the impact of the type of CEO on the capacity of innovation shows that market-oriented, technology-driven and consultant-type CEOs have a significant impact on the amount of technology change reduction, but managed CEOs do not see any statistically significant differences in the amount of technology change reduction areas. Managed CEOs did not see statistically significant differences in the amount of technology change-sensitive areas. In addition, it was analyzed that the current type of CEO of small businesses does not affect the R&D technology digestion capacity of technological innovation capabilities. Second, the analysis of the relationship between innovation capabilities and innovation performance did not have a statistically significant effect. Third, the analysis of the adjustment effect between the type of CEO and the capacity of innovation according to the growth stage of small businesses shows that the technology and the consultant-type CEO affect the amount of the area of technology change, but the managed and market-type CEOs did not have the adjustment effect. Fourth, the analysis of the capacity of innovation and the effect of adjustment between innovation and innovation in the growth phase of innovative SMEs did not have a statistically significant effect.

The Voluntary Assurance of Quality by Contractors in the Construction Phase (건설 공사단계에서 수급자 중심의 품질확보방안)

  • Cha, Sang-Ho;Lee, Sang-Beom
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.3
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    • pp.292-300
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    • 2011
  • The construction industry in Korea has seen significant improvements in quality management techniques, driven by the dramatic development of new technology through Manhattanization and enlargements, but compared with technical development, the level of building quality improvement is still lagging behind. In the meantime, as the interest in construction quality soars due to changes in user consciousness, the level of quality that is being demanded is rising. The government has reinforced quality systems by implementing responsible supervision requirements and granting overseas companies permission to enter the supervision business in Korea, and private sector companies also are attempting quality improvement through quality assurance approaches like the preliminary qualification screening system and ISO 9000 series. But currently, building constructions are done only according to the construction specifications of project owners, whose design, materials and construction methods are already decided, and do not leave any necessity or opportunity for technical developments for the quality improvement of contractors. Therefore, in this study, a work process and system improvement plan for payment regulations is proposed, with which contractors can secure quality voluntarily in the building construction phase.

A Study on the Unfair Aspect of Specific Provisions in the Construction Contract : Counterplan and Institutional Reformation (건설공사 계약서상 불공정특약에 대한 대처방안 및 제도개선에 관한 연구)

  • Choi Jea-Won;Park Keun-Hyung;Kim Yong-Su
    • Korean Journal of Construction Engineering and Management
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    • v.5 no.6 s.22
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    • pp.146-153
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    • 2004
  • The purposes of this study are to survey unfair aspects of specific provisions in the construction contract, and to suggest counterplans and institutional reformations. The research method of this study includes judicial precedent analysis and a questionnaire survey, The results of this study are as follows: 1) the main problems of unfair specific provisions are payment condition, shifting of the responsibility and adjustment in the contract sum. 2) counterplans ate suggested according to the construction phase : bid, construction and completion phase. 3) institutional reformations include firming up regulations, supervision, invigoration of claim, development of variation guideline, and so on.

The Study on Korean Prosody Generation using Artificial Neural Networks (인공 신경망의 한국어 운율 발생에 관한 연구)

  • Min Kyung-Joong;Lim Un-Cheon
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.337-340
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    • 2004
  • The exactly reproduced prosody of a TTS system is one of the key factors that affect the naturalness of synthesized speech. In general, rules about prosody had been gathered either from linguistic knowledge or by analyzing the prosodic information from natural speech. But these could not be perfect and some of them could be incorrect. So we proposed artificial neural network(ANN)s that can be trained to team the prosody of natural speech and generate it. In learning phase, let ANNs learn the pitch and energy contour of center phoneme by applying a string of phonemes in a sentence to ANNs and comparing the output pattern with target pattern and making adjustment in weighting values to get the least mean square error between them. In test phase, the estimation rates were computed. We saw that ANNs could generate the prosody of a sentence.

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A Study on Improving Mass Production of the Radar Sensor Oscillator (레이더 센서용 발진기의 양산성 향상에 관한 연구)

  • Kim, Byung-Chul;Cho, Kyung-Rae;Lee, Jae-Buom;Kim, Dae-Hyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.4
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    • pp.669-676
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    • 2012
  • In this paper, The method to improve the mass production method of the radar sensor is suggested by using the temperature compensation circuit which is composed with the thermister. The mass production became easier by decreasing the adjustment time for the exact oscillation frequency with the temperature compensation circuit that can support the proper gate bias voltage for the FET after the dielectric resonator is removed from the DRO(Dielectric Resonator Oscillator) of the radar sensor. Radar sensor with the proposed method has 15.67MHz oscillator frequency variation in the temperature range of $-20^{\circ}C-+55^{\circ}C$, 0.65dB magnitude variation, -105.47dBc phase noise characteristics at 1MHz which are better or similar temperature characteristics with the DRO whose oscillator frequency variation is 25MHz, magnitude variation is 0.42dB and phase noise is -107.40dBc in the same temperature range.