• Title/Summary/Keyword: silent period

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Design Program of Low Noise Centrifugal Fans (저소음 원심형 홴의 설계 프로그램)

  • 박준철;손정민;김기황;이승배
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.11a
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    • pp.529-535
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    • 2001
  • A centrifugal fan design code was developed and packaged together with iDesignFan/sup TM/ as new models. This code generate centrifugal forward curved and backward curved bladed impeller optimally. It also predicts the aerodynamic performance and the overall sound pressure level of the rotating fan by assuming steady blade loading. The overall sound pressure level is used as an input parameter from the third loop of the designing process to acquire the most silent fan for the given aerodynamic performance parameters. With this kind of inverse design concept used in the code, the period of designing a fan is significantly shortened. A centrifugal fan design code, developed in this study and included in iDesignFan/sup TM/, predicts the aerodynamic performance such as design flow rate and static pressure. The aerodynamic performance in the design and off-design conditions is calculated by using the mean line analysis. For the steady loading calculation, the lift force distribution in a blade is used.

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A Tendency of Study on Theory of Impression Formation by Clothing (의복의 인상형성이론에 대한 연구동향)

  • 이경화;나수임
    • The Research Journal of the Costume Culture
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    • v.7 no.1
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    • pp.117-127
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    • 1999
  • Clothes are a kind of silent language that tells someone who has in wear and has great influence on person perception and impression formation. Present paper aims, therefore, to investigate the tendency of its study to offer information that my assist future studies. Doctorial dissertations, master\`s theses and journal articles related with clothing and textiles in domestic are categorized according to period and subject. Analysed results are as follows: First, as for the periodic vicissitude, the number of study on impression formation was before 1990, but tend to increase in 1990\`s. Second, as for the subject, while the studies focused on impression formation wearer on the first half of 1990\`s, they were segmented and presented wearer\`s form and appearance in detail ; computer simulation was also made use of in various papers. In conclusion, impression formation seems to become a rather important subject for further study.

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Performance Analysis of modified PRMA: PRHMA(Packet Reservation Hold Multiple Access) (변형된 PRMA 방식인 PRHMA의 성능분석)

  • Kim Hwan Ui;Kim Doug Nyun
    • Journal of the Institute of Convergence Signal Processing
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    • v.1 no.2
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    • pp.122-130
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    • 2000
  • This paper mainly deals with the modified version of conventional PRMA(Packet Reservation Multiple Access). In the existing PRMA schemes, the occupied slot in the initial access state is not allowed to be reserved in the silent period and retrial of gaining the slot access has to pay additional packet dropping. Whereas in the modified model, we propose to utilize a control minislot that maintains slot reservation and this prevents additional packet drop occurrence since initial access, and this slightly improves the system performance.

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AN ELECTROMYOGRAPHIC INVESTIGATION OF MASTICATORY MUSCLES IN NORMAL OCCLUSION AND CLASS II MALOCCLUSION (저작근 근전도에 관한 정상교합자와 II급 부정교합자의 비교 연구)

  • Kim, Yeon-Kyung;Lee, Ki-Soo;Park, Young-Guk
    • The korean journal of orthodontics
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    • v.22 no.2 s.37
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    • pp.389-412
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    • 1992
  • Along with form and function relationship of craniofacial growth comes a concern for the masticatory muscles with postnormal occlusion. It is the aim of this study to grope the certain differences upon the electromyographic activities of the masticatory muscles between normal occlusion and class II malocclusion during the varieties of oral functions. 26 persons of normal occlusion whose mean age were 18.9-25.6 years and another 26 persons of class II malocclusion whose mean age were 19.0-28.9 years served for this study. The electromyographic recordings processed by $Medelec^{\circledR}$ MS 25 EMG apparatus were taken from the anterior and posterior temporal, and anterior and posterior masseter muscles of both sides, and suprahyoid muscles as well. Analyses of the data toward such specific activities as mandibular rest, maximal biting, chewing gums and swallowing peanuts turned out the following summary and conclusions. 1. The maximal mean amplitude of the posterior temporalis showed significant augmentation in class II malocclusion, however the anterior temporalis, posterior masseter, and suprahyoid muscles manifested meaningful diminutions. 2. Stronger posterior temporalis and weaker anterior masseter and suprahyoid muscles were arranged in maximal biting with parameters of maximal mean amplitude. 3. The anterior temporalis of working side expressed smaller maximal mean amplitude in class II malocclusion. Significant swelling in duration were shown at anterior and posterior temporalis of working side, and posterior temporalis of balancing side in class II malocclusion, and marked reduction at anterior masseter of balancing side and posterior masseter of working side as well. The lessened latency were expressed at anterior masseter of working side, and anterior and posterior masseter of balancing side. Class II malocclusion group had significant prolongation of silent period duration. Mean silent period duration of 10.75 msec in normal occlusion and 24.37 msec in class II malocclusion were calculated. 4. Significant augmentations of maximal mean amplitude while swallowing peanuts were yielded at right anterior temporalis and posterior temporalis of both sides, however left anterior masseter and right posterior masseter showed diminution. No significant differences in duration showed at every muscle examined in class II malocclusion group.5. Weaker masseter and stronger temporalis were suggested as characteristics of class II malocclusion.

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Sthdies on the Adaptability for Frozen fish Meat Paste Processing of the Fishes Cought in korean coastal Off-Shore Sea (냉동연육 원료로서연근해산 어류의 가공적성 검사연구)

  • 류지동;이성갑
    • Journal of the Korean Professional Engineers Association
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    • v.32 no.4
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    • pp.104-118
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    • 1999
  • Alaska Pollack (Theragramma), Mackerel (Socomber japonicus), yellow corvenia (Pseudosc iance manchurica) were dressed, and then meat was separated from the other parts through a fish meat separator. After dehydration, the meat was ground with a silent cutter, packaged in polyethylene bags, and stored at -15。C for days. Samples were taken at regular intervals throughout the storage period and investigated for changes in puality characteristics such as the amounts of nitrogenous compounds, degree of lipid oxidation, fatty acid composition, and organoleptic factors. The resrlts obtained in this study were as follows; 1. The volatile basic nitrogen[VBN] contents of Alaska pollack, and yellow corvenia meat pastes increased from 14.4, 11.2 and 10.8mg% to 41.6, 38.3 and 40.6mg%, respectively during a 120 day storage period, whereas the trimethylamine oxide nitrogen [TMAO-N] contents decreased from 117.2, 12.8 and 17.2mg% to 40.3, 2.6 and 7.1mg% during the same period. 2. The TBA value of the mackerel meat paste showed a maximum peak after 60 days, and then decreased gradually, whereas the TBAvalues of the alaska pollack and yellow corvenia meat pastes increased steadily during the same period. The acid values of the meat pastes increased during the storage period, while the iodine values decreased. 3. The fatty acid composition of the total lipid of the meat pastes changed considerably during ghe 120 days storage period : saturated fatty acids in the total lipid such as myristic, palmitic, and stearic acid increased, while unsaturated fatty acids such as linoleic, gadoleic, eicosapentaenoic, erucic and docosahexaenoic acid decreased steadily. The initial percentage contents of the unsaturated fatty acids in the total lipid of the Alaska pollack, mackerel, and yellow corvenia meat pastes were 87.2%, 63.9%, and 75.9% respectively. However, the contents decreased to 46.0%, 42.5% and 51.3% after the 120day storage period. 4. The color of the meat pastes changde gradually into dark brown. L values of the meat paste measured with a thistimulus colorimeter decreased steadily during the storage period, while a and b values increased during same period. 5. Judging from the results of organoleptic evaluation on the fish odor, color and overall acceptability, significant difference were found between the odor and color of the mackerel and those of the yellow corvenia meat pastes. Overall acceptability score of yellow corvenia was higher than that of Alaska pollack or mackerel meat pastes.

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Studies on Development of Breeding Technique to Increase Hanwoo (Bos taurus coreanae) III. Hormonal Treatment of Reproductive Disorders and Effect of Intraovarian $\textrm{PGF}_{2a}$ Administration in Hanwoo (한우의 신속한 증식을 위한 번식기술 개발에 관한 연구 - III. 한우에서 번식장애 처치 및 $\textrm{PGF}_{2a}$의 난소실질내 투여효과에 관한 연구)

  • 손창호;오병철;임원호;백종환;오명환;이강남;정근기;강성근;김대영
    • Journal of Embryo Transfer
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    • v.17 no.2
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    • pp.153-162
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    • 2002
  • In order to develop the breeding techniques to increase Hanwoo (Bos taurus coreanae) population, the present study was performed 1) to establish the treatment protocol on reproductive disorders with GnRH or PGF/sub 2$\alpha$/, 2) to improve intraovarian PG $F_{2}$$\alpha$/ administration for reducing open period. Among total of 43 diagnosed, high percentage of cows (41.9%, 18 cows) were diagnosed as silent heat, followed by inactive ovaries (32.6%, 14 cows), ovarian cysts (9.3%, 4 cows), persistent corpus luteum (7.0%, 3 cows), endometriosis (4.7%, 2 cows), pyometra (2.3%, 1 cow) and luteal cysts (2.3%, 1 cow). To treat silent heat, 18 cows were administrated with 25 mg PGF/sub 2$\alpha$/, heat-detected, artificially inseminated and monitored pregnancy. All treated cows were heat-detected and 16 cows (88%) were successfully pregnant. With 200 $\mu\textrm{g}$ GnRH treatment, 7 cows (70%) with inactive ovaries and 3 cows (75%) with ovarian cysts were successfully pregnant. Administration with 25mg PGF/sub 2$\alpha$/, successfully treated 3 cows (100%) with persistent corpus luteum and 1 cow (100%) with luteal cysts, followed by 100% pregnancy rate. With the combined treatment of 25 mg PG $F_{2}$$\alpha$/and antibiotics, 2 cows (100%) with endometriosis were effectively treated and got pregnant after. artificial insemination (AI). In order to reduce open period, 5 mg PGF/sub 2$\alpha$/ was administrated intraovarian to 20 days cows after delivery, heat-detected, artificially inseminated and monitored pregnancy. In the first experiment, in order to recover uterus, 5mg PGF/sub 2$\alpha$/were administrated, followed by administration of 5mg PGF/sub 2$\alpha$/ at the interval of 14 days. As results, 74% (17/23 cows) of pregnancy rate after AI. In order to further reduce the open period, 5 mg PGF/sub 2$\alpha$/was administrated at the interval of 11 days without the period of uterus recovery, resulted in 94% (16/17 cows) pregnancy rate. In conclusion, these results showed that PGF/sub 2$\alpha$/ and GnRH treatment were effective hormonal treatment resume in Hanwoo with various reproductive disorders. In addition, modified protocol of intraovarian PGF/sub 2$\alpha$/ administration could be the effective method for reducing the open period.

Dual-Phase Approach to Improve Prediction of Heart Disease in Mobile Environment

  • Lee, Yang Koo;Vu, Thi Hong Nhan;Le, Thanh Ha
    • ETRI Journal
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    • v.37 no.2
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    • pp.222-232
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    • 2015
  • In this paper, we propose a dual-phase approach to improve the process of heart disease prediction in a mobile environment. Firstly, only the confident frequent rules are extracted from a patient's clinical information. These are then used to foretell the possibility of the presence of heart disease. However, in some cases, subjects cannot describe exactly what has happened to them or they may have a silent disease - in which case it won't be possible to detect any symptoms at this stage. To address these problems, data records collected over a long period of time of a patient's heart rate variability (HRV) are used to predict whether the patient is suffering from heart disease. By analyzing HRV patterns, doctors can determine whether a patient is suffering from heart disease. The task of collecting HRV patterns is done by an online artificial neural network, which as well as learning knew knowledge, is able to store and preserve all previously learned knowledge. An experiment is conducted to evaluate the performance of the proposed heart disease prediction process under different settings. The results show that the process's performance outperforms existing techniques such as that of the self-organizing map and gas neural growing in terms of classification and diagnostic accuracy, and network structure.

Impact of Voice Activity Detection on Channel Allocation in Cellular Networks

  • Limsaksri, Wichan;Thipchaksurat, Sakchai;Varakulsiripunth, Ruttikorn
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1067-1071
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    • 2004
  • In this paper, the performance enhancement algorithm of channel allocation for voice and data transmission in cellular networks is proposed. The voice activity detection has been applied to dynamic channel allocation procedure to detect and separate the silence and speech among conversation periods. Hence a data user can use the silent period of an active voice channel to transmit its information. To control the selecting of channel allocation policies, the information of number of data in transmission waiting queue has been determined in order to accept the performance measurement. In the simulation results, the improvement of the performance shows via the quality of services, which are an average delay in queue, a blocking probability, and an impact of the proposed scheme is presented in the system.

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A Novel Hitting Frequency Point Collision Avoidance Method for Wireless Dual-Channel Networks

  • Quan, Hou-De;Du, Chuan-Bao;Cui, Pei-Zhang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.3
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    • pp.941-955
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    • 2015
  • In dual-channel networks (DCNs), all frequency hopping (FH) sequences used for data channels are chosen from the original FH sequence used for the control channel by shifting different initial phases. As the number of data channels increases, the hitting frequency point problem becomes considerably serious because DCNs is non-orthogonal synchronization network and FH sequences are non-orthogonal. The increasing severity of the hitting frequency point problem consequently reduces the resource utilization efficiency. To solve this problem, we propose a novel hitting frequency point collision avoidance method, which consists of a sequence-selection strategy called sliding correlation (SC) and a collision avoidance strategy called keeping silent on hitting frequency point (KSHF). SC is used to find the optimal phase-shifted FH sequence with the minimum number of hitting frequency points for a new data channel. The hitting frequency points and their locations in this optimal sequence are also derived for KSHF according to SC strategy. In KSHF, the transceivers transmit or receive symbol information not on the hitting frequency point, but on the next frequency point during the next FH period. Analytical and simulation results demonstrate that unlike the traditional method, the proposed method can effectively reduce the number of hitting frequency points and improve the efficiency of the code resource utilization.

A Study on the Voice Traffic Efficiency and Buffer Management by Priority Control in ATM Multiplexer (ATM 멀티플렉서에서 우선순위 제어에 의한 음성전송효율 및 버퍼관리에 관한 연구)

  • 이동수;최창수;강준길
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.2
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    • pp.354-363
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    • 1994
  • This paper describes the method that voice traffic is served efficiently in BISDN. Voice is divided into talkspurt and silent period, and it is possible to transmit olny talksurt by the speech activity detection. This paper described the voice traffic control algorithm in the ATM network where cell discarding method is applied to the embedded ADPCM voice data. For traffic control, the cell discarding was used over low priority cells when it overflows the queue threshold. To estimate the efficiency of traffic control algorithm, the computer simuation was performed with cell loss probability, queue length and mean delay as performance parameters. The embedded ADPCM voice coding and cell disscarding resulted in improving the voice cell traffic efficiency and the dynamic control over network congestion.

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