• Title/Summary/Keyword: PN

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A PN-code Acquisition method Using Array Antenna Systems for CDMA2000 1x (CDMA2000 1x용 배열 안테나 시스템에서 PN 동기 획득 방법)

  • Jo, Hee-Nam;Yun, Yu-Suk;Choi, Seung-Won
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.8 s.338
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    • pp.33-40
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    • 2005
  • This paper presents a structure of the searcher using a diversity in array antenna systems operating in the cdma2000 1x signal environments. The new technique exploits the fact that the In-phase and quadrature components of interferers can respectively be viewed as an independent gaussian noise at each antnna element in most practical cdma signal environments. The proposed PN acquisition scheme is a singles-dwell PN acquisition system consisting of two stages, that is, the searching stage and the verification stage. The searching stage independently correlates the receiver multiple signals with PN generator of each antenna element for obtaining the synchronous energy at the entire region. Then, the searching results of each antenna element are non-coherently combinind. The verification stage compares the searching energy with the optimal threshold, which is predesigned in the lock detector, and decides whether the acquisition is successful or fail. In this paper, we analyzed the effect of tile diversity order to determine the mean acquisition time. In general, it is known that the mean acquisition time significantly decrease as the number of antenna elements increases. But, as the diversity order goes up, the enhancement of the performance is saturated. Therefore, to decrease the mean acquisition time of the searcher, we must design the optimal array antenna systems by considering the operating SNR range of the receiver, the probability of detection $P_D$ and that of false alarm $P_{FA}$ . The Performance of the proposed PN acquisition scheme is analyzed in frequency selective Rayleigh fading channels. In this paper, the effect of the number of antenna elements on PN acquisition scheme is shown according to the probability of detection $P_D$ and that of false alarm $P_{FA}$.

Poor Prognostic Factors in Patients with Parenteral Nutrition-Dependent Pediatric Intestinal Failure

  • Choi, Shin Jie;Lee, Kyung Jae;Choi, Jong Sub;Yang, Hye Ran;Moon, Jin Soo;Chang, Ju Young;Ko, Jae Sung
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.19 no.1
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    • pp.44-53
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    • 2016
  • Purpose: Parenteral nutrition (PN) not only provides nutritional support but also plays a crucial role in the treatment of children with intestinal failure. The aim of this study was to evaluate the clinical significance and clinical outcomes of long-term PN. Methods: Retrospective cohort study was conducted using the medical records of patients treated at Seoul National University Children's Hospital. This study included 19 patients who received PN for over six months. Most patients received home PN. Results: The indications for PN included short bowel syndrome, chronic intestinal pseudo-obstruction, and intractable diarrhea of infancy. The median age of PN initiation was 1.3 years, and the median treatment duration was 2.9 years. Two patients were weaned from PN; 14 continued to receive PN with enteral feedings; and 3 patients died. The overall survival rates at 2 and 5 years were 93.3% and 84.0%, respectively. The incidence of catheter-related bloodstream infections was 2.7/1,000 catheter-days and was associated with younger age at PN initiation and lower initial height Z-score. Six patients developed catheter-related central vein thrombosis, with an incidence of 0.25/1,000 catheter-days. Eleven patients experienced PN-associated liver disease (PNALD), and one patient underwent multi-visceral transplant. The patients with PNALD exhibited lower final heights and body weight Z-scores. All patients experienced micronutrient deficiencies transiently while receiving PN. Conclusion: PN is an important and safe treatment for pediatric intestinal failure. PNALD was linked to final anthropometric poor outcomes. Micronutrient deficiencies were common. Anthropometric measurements and micronutrient levels must be monitored for successful PN completion.

Tissue- and Reproductive Organ-specific Expression of Protease Nexin-1 in Sprague-Dawley Rat (흰쥐에서 단백질 분해효소 저해제, Nexin-1의 조직 및 생식기관 특이적 유전자 발현)

  • 고정재;김남근;김진규;최명진;정형민;서승염;김윤희;이현환;차광열
    • Development and Reproduction
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    • v.2 no.2
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    • pp.135-140
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    • 1998
  • Protease Nexin-1 (PN-1) inhibits the activity of several serine proteases including thrombin, urokinase (uPA)-type plasminogen activator and trypsin. Tissue- and reproductive organ-specific mRNA levels of the PN-1 were investigated in Sprague-Dawley adult rat. PN-1 mRNA expression in rats was found in brain (forebrain, hindbrain), heart, liver, lung, ovary and oviduct. The level of PN-1 mRNA in male and female among the tissues was the highest in forebrain of the female. PN-1 expression in reproductive organs was found only in ovary and oviduct. These results suggest that PN-1 expression is dependent on the sex and may be related to folliculogenesis and early embryogenesis.

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Detection of Adulteration of Sesame Oil (II). Chromatographic Determination of Rapeseed Oil in Sesame Oil (참기름의 진위판정에 관하여(II) 참기름중의 채종유의 검출)

  • 천석조;임영희;송인상;노정배
    • Journal of Food Hygiene and Safety
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    • v.3 no.3
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    • pp.105-109
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    • 1988
  • To develop a method for detecting and e&timating the quantity of adulterant rapeseed oil in sesame oil, five kinds of sesame oils and three kinds of rapeseed oils collected from different sources were fractionated by TLC (thin layer chromatography) and separated on the basis of PN (partition number) by HPLC (high performance liquid chromatography). These obsenations indicate that the proportion of adulterant rapeseed oil when mixed minimum 4% with sesame oil can be detected.

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Detection of Adulteration of Sesame Oil(I) Chromatographic Determination for Soybean Oil, Linseed Oil and Perilla Oil in Sesame Oil (참기름의 진위 판정에 관하여 - (I) 참기름중의 대두유, 아마인유 및 들깨기름의 검출)

  • 천석조;임영희;송인상;노정배
    • Journal of Food Hygiene and Safety
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    • v.3 no.2
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    • pp.59-63
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    • 1988
  • A technique of high-performance liquid chromatography (HPLC) was applied to tbe detection and estimation for composition of linseed oil, perilla oil and soybean oil in edible sesame oil. Tbe triglycerides were separated into five peaks in sesame 011, seven peaks in linseed oil, perilla oil and soybean oil by HPLC. From the resulls separated by HPLC on the basis of PN (partition number), tbese observations indicate tbat adullerants linseed oil, perilla oil and soybean oil in sesame oil for the ratio of minimum 4%, respectively can be detected. As a resull, it was suggested that tbe use of HPLC can provide more detailed Information concerning adulteration of sesame all.

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Rapid Acquisition of m-sequence Signals by Sequential Estimation with Flexible Structure (가변구조를 갖는 순차 예측 방법을 이용한 m 계열 신호의 고속 포착)

  • 현광민;박상규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.7B
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    • pp.664-672
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    • 2002
  • This paper analyzes a sequential estimator with flexible structure for rapid acquisition of the m-sequence signals. If the received PN chips stored in the estimator's internal registers as initial loading values include one error, this chip with error can be corrected through multiple local PN code generators to achieve high-speed acquisition performance. Hamming distance between regenerated local PN codes from the proposed system and received PN code is compared with given threshold to choose a possible correct path and to declare success of the code acquisition. Using signal flow graph, average acquisition time that depends on detection and false alarm probability is calculated. By modifying generally used matched filter structure for PN code acquisition, the proposed system provides flexible structure and rapid acquisition process.

A new PN code acquisition algorithm using a reference code (Reference code를 이용한 새로운 PN code 획득 알고리즘)

  • 이승환;김운경;박재영
    • Proceedings of the IEEK Conference
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    • 2002.06a
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    • pp.279-282
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    • 2002
  • Here we introduce so called Reference code-weighted sum of all PN codes used in the system-. We do inner product operation between received PN code and Reference code rather than locally generated PN code in the receiver. Acquisition process can be accomplished by only one inner product during full period of PN code. It's essential innovation against present method which can be viewed successive hypothesis test by inner product for entire candidate PH codes set. Well -defined decision region makes it possible. We suggest the. criterion fur designing the decision region and find a condition for weight (coefficient) of Reference code.

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Phase Offset Enumeration Method with Error Detection and Its Application to Synchronization of PN Sequences

  • Song Young-Joan
    • Journal of electromagnetic engineering and science
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    • v.5 no.1
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    • pp.26-30
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    • 2005
  • It is important to know phase offsets of PN(Pseudo Noise) sequences in spread spectrum communications since the acquisition is equivalent to making a phase offset between a receiving PN sequence and a PN sequence of local PN generator be identical. In this paper, a phase offset enumeration method for PN sequences with error detection, and its application to the synchronization are proposed. The phase offset enumeration for an n-tuple PN sequence and its error detection are performed when one period of the sequence is received. Once the phase offset of the receiving sequence is calculated, we can easily accomplish the synchronization by initializing shift registers of a local PN generator according to the phase offset value. The mean acquisition time performance of the proposed scheme was derived analytically. Since this synchronization scheme can be realized by using simple circuit and acquires very rapid acquisition in high SNR but shows performance degradation in low SNR, it can be especially useful in indoor and office environments.

Ring Opening Polymerization of Lactone Using Polyethers (폴리에테르를 이용한 락톤의 개환중합)

  • 이찬우;오세화;배기서
    • Textile Coloration and Finishing
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    • v.10 no.5
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    • pp.32-38
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    • 1998
  • Glycolides were polymerized by PPG or Pluronic(PN) to give A-B-A block copolyesters consisting of polyglycolide(A) and polypropylene glycol(B) or polyglycolide(A) and PN (B). Lactones were easily copolymerized with polyethers by ester interchange reaction even in the absence of catalyst. It is because PPG and PN are telechelic polyethers having hydroxy groups on their both ends. When the feed ratio of PPG(M$_{n}$=4,000) and PN(M$_{n}$=11,500) were over 5 and 10 wt% .elative to glycolide, respectively, the polymerization of glycolide took place from the terminus hydroxy groups of PPG or PN to produce the desired A-B-A block copolymers in high yields. The molecular weights of the copolymers, which estimated from the monomer conversions and the feed ratios of PPG and PN, could be controlled by changing the kind of terminus hydroxy of polyether and the feed molar ratio of PPG and PN. PN.

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On Optimal PN Code Acquisition (최적화된 PN Code Acquisition에 대한 연구)

  • Jang, U-Jin
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.23-25
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    • 1998
  • Many of the currently used PN code acquisition algorithms detect the phase of the incoming PN signal on the basis of ML estimation principle and utilize statistics grounded in taking inner products. By showing that any set of 2n-1 PN sequences arising in SSRG or MSRG (those typically used in IS'95 implementations) configuration constitutes a linearly independent set and that the number of candidate PN sequences has to equal the dimension of the span of the candidate PN sequences, we prove that the lowerbounding computational complexity involved in any PN code acquistion, utilizing (only) inner product computations at each stage of acquisition, corresponds precisely to those, such as double dwell acquistion circuitries, currently used.

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