• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.38 no.10
• /
• pp.687-698
• /
• 2001

This paper presents a three dimensional stacked pad area away (PAA) package configuration as an implementation method of radio frequency (RF) circuits. 224MHz RF circuits of intelligence traffic system(ITS) were constructed with the stacked PAA RF pakage configuration. In the process of manufacturing the stacked PAA RF pakage, RF circuits were partitioned to subareas following their function and operating frequency. Each area of circuits separated to each subunits. The operating characteristics of RF PAA package module and the electrical properties of each subunits were examined. The measurement of electrical parameters for solder balls which were interconnects for stacked PAA RF packages showed that the parasitic capacitance and inductance were 30fF and 120pH, respectively, which might be negligible in PAA RF packaging system. HP 4396B network/spectrum analyzer revealed that the amplification gain of a receiver and transmitter at 224 MHz was 22dB and 27dB, respectively. The gain was 3dB lower than designed values. The difference was probably generated from fabrication process of the circuits by employing commercial standard

• Parasites, Hosts and Diseases
• /
• v.31 no.2
• /
• pp.129-134
• /
• 1993

Intestinal mucosal mast cell (MMC) responses were studied in rats experimentally infected with Metngonimur yokogawai (Dlgenea: Heterophyidael. Twenty Sprague-Dawley rats were fed each 2,500 metacercariae isolated from the sweetish and sacrificed on the week 1, 2, 3 and 4 post-Infection (PI). Recovery of worms was performed from the small intestine of each rat. To visualize the MMCs, duodenal and jejunal (upper, middle and lowers) tissue sections were made and stained with alcian blue/safranine-0. The average worm recovery rates were 16.2% and 13.8% on the week 1 and week 2, respectively, but they decreased rapidly to 4.1% and 4.2% on the week 3 and week 4 PI, respectively, which indicate spontaneous worm expulsion after the week 2. The MMC number In the Infected rats was, compared with uninfected controls, significantly Increased In the whole small intestine, through the whole period of observation. The peak level of mastocytosis was observed on the week 3 PI. It is strongly suggested that MMCs might be involved In the expulsion process of flukes from the rat intestine.

• Parasites, Hosts and Diseases
• /
• v.31 no.1
• /
• pp.49-56
• /
• 1993

Specific antibody test in serum and cerebrosinal fluid (CSF) is still the main mode of serological diagnosis of cystiercosis. Of different techniques of artibody test, enzyme-linked immunosorbent assay (micro-ELISA) has widely been applied. This study was undertaken to observe whether diagnostic capability can be Improved by applying more sensitive techniques such as Protein A-ELISA and avidin biotin complex ELISA (ABC-ELISA). When evaluated using 115 sera of human cysticercosis, the antibody positive rates were not significantly improved in Protein A-ELISA (82.6%) and in ABC-ELISA (86.1%) than in micro-ELISA (81.7%). The specificities, evaluated in 165 sera from other diseases and normal controls, were significantly improved (88.5% by micro-ELISA, 93.3% by Protein A-ELISA and 93.8% by ABC-ELISA). Antibody levels (absorbance, abs.) in individual serum were correlated well (r : 0.83∼0.86) each other. An actual benefit of Protein A-ELISA and ABC-ELISA was that they needed smaller amount of test sample.

• Parasites, Hosts and Diseases
• /
• v.27 no.3
• /
• pp.217-224
• /
• 1989

Four females and a male nematode isolated from 2 patients who visited eye clinics In Seoul were identified as Thelazia callipaeda and their ultrastructures were observed by scanning electron microscopy(SEM). General features of the worms were slender and attenuated at both ends. Vaginal opening was located at 0.27 mm from the anterior end, and in front of the esophagointestinal junction. In the body cuticle transverse striations varied characteristically through the body. The number of cuticular transverse striations was 400∼650/mm at head portion, 250/mm at middle portion and 300∼350/mm at tail portion. The SEM observation of the mouth part of the females showed 6 cord-like cuticular thickenings in hexagonal arrangement and an amphid was observed. A lateral line, a vaginal opening, a pair of phasmids, and an anus were identified in the body portion. A pair of papillae and 6 cord-like cuticular thickenings were on the mouth part of the male. It was difficult to observe structures at the tail of the male except wrinkle-like structures. Most of the larvae isolated from the uterus of a female worm were sheathed and thus cuticular striations were not Eren. Others were unsheathed and revealed cuticular striations. The oval membrane which encysted sheathed larvae was also observed. These are the 18th and 19th record of human thelaziasis in Korea as the literature are concerned.

• Parasites, Hosts and Diseases
• /
• v.35 no.3
• /
• pp.155-164
• /
• 1997

Studies were conducted from May, 1993 to April, 1995 to determine the changing patterns of infection Ity the liver fluke, Clonorchis sinensis, among residents and fish hosts in Kyongbuk Province. The infection rate among residents was 7.7% by stool examination. The rate in males (11.3%) was significantly higher than females (4.1%) Positive rate of intradermal test was 27.6% in the same population. The special type of a simple catalytic model was applied for the analysis of intradermal positive reactors by age arid sex, ann the equation was Y= 0.4776 t (1 -e-0.0375t) for mates ann, y : 0.2085 (1-e-0.0138t) for females. Analysis of stool examination data by two-stage catalytic model revealed y : 0.025 (e-0.0047t _ e-0.0235t). The annual Clonorchis infection rate was 4.7 per 1,000 susceptibles and the annual loss rate was 23.5 per 1,000 infected. The frequency distribution by the eggs per gram (EPG) was calculated as well as the cumulative percentages of positives. The regression equations were y : 0.929+ 1.506 log x for males and, y : 0.473 + 1.767 log x for females. Of the 25 fish species, 7 species were infected with Clonorchis mrtacercariae. Infection rates varied by the species, and ranged from 2.8% in Punfun,Bia herzi to 30.0% in Pseudorasbora panic. Average number of the matacercariae per gram of flesh was 58.1 in p. pnnpa, followed by 10.2 in Gncthopogon atromoculntus, 7.0 in Saurosobio dobryj, and 3.0 in Pcrccheilogncthus rhonlben. The present study indicates that clonorchiasis in Kyongbuk Province is less prevalent than that of several decades ago.

• Korean Journal of Agricultural Science
• /
• v.6 no.1
• /
• pp.33-44
• /
• 1979

These studies were carried out to investigate the effects of liver-fluke infection on the reproductive disorder and milk and meat production in Korean Native Goat. A survey of infected goat in Chungnam district was conducted with 474 head by interdermal reaction and also a clinical observation was founded. A experiment was carried out to determine the effects of liver fluke extract on the reproductive disorder by subcutaneous injection and milk and meat yield were measured from treat ed goats. The results obtained were summarized as follows. 1. The rate of positive goat was 71.3% among the surveyed goat and the highest rate was appeared at 3~4 years old goats as 81.4%. 2. The treated goats lost condition and failed to thrive, and became progressive weaker. 3. In hemogram, observation, the rate of eosinophil leucocyte was increased significantly by extract treated. 4. It was appeared the pathogenic signs such symptoms poisoning liver function disturbance and reproductive disorder from treated goats with liver fluke extract. 5. In milking goat the milk yield droped significantly and fattening goat did not fatten. 6. The gross income value per capita was lower from infected goat and it was analysed more sensitivly in net income value.

• Parasites, Hosts and Diseases
• /
• v.32 no.1
• /
• pp.57-60
• /
• 1994

In order to search the fate of Thelohonellus kitauei spores the extrusion rates of the polar filaments were monitored in uipo chronologically. Preserved spores suspended with various solutions at $-70^{\circ}C$ showed almost the same vigorous pattern as early freezing stages up to 1,750 days after initial preservation. It revealed that the vlabllltles of some spores suspended with 0.45% and 0.9% NaCl solutions and distilled water at $5^{\circ}C$ continued for 1,628 days, 1,614 days and 1,721 days, respectively. And, the life spans of some spores in the previous solutions added with antibiotics at $5^{\circ}C$ were 1,628 days, 1,614 days and 1,714 days, respectively. Key words: TheLohanellus kitnuei, spore, extrusion rate of polar filament, life span

• Proceedings of the KIPE Conference
• /
• 2020.08a
• /
• pp.233-235
• /
• 2020

본 논문은 40 kV 나노초 펄스발생을 위한 모듈형 solid-state Marx modulator(SSMM) 설계에 대해 기술한다. 가속기 및 플라즈마 어플리케이션과 같은 다양한 응용분야에 요구되는 전압 및 전류 사양을 만족시키기 위해 10 kV(출력 전압), 50 ns(펄스폭), 20 ns(상승&하강 시간), 100 kHz(반복률)의 사양을 만족하는 단위모듈기반으로 모듈형 설계를 제안한다. 독립적인 제어가 가능한 4개의 단위모듈을 기반으로 제안된 SSMM은 임의의 출력 파워 및 임피던스를 만족시킬 수 있는 장점을 가지고 있다. 예를 들어, 모든 단위모듈의 위상을 같게 했을 때 출력전압을 증가시킬 수 있으며 각 모듈의 위상을 지연하였을 경우는 펄스의 반복률을 크게 높일 수 있다. 개발된 SSMM은 직렬 스택 MOSFET의 스위칭 성능을 향상시키기 위해 게이트 구동 회로는 동기 신호와 구동 전력을 제공하는 1 턴 변압기로 설계되었다. 출력 펄스의 폭과 하강시간을 최소화하기 위해 다이오드 대신 기생 커패시턴스에 저장된 에너지를 빠르게 방출하는 액티브 풀다운 회로가 적용되었다. 또한, 출력 펄스의 빠른 상승을 달성하기 위해 게이트의 라인 인덕턴스를 최소화하고 모든 게이트 신호의 동기화는 필수적이다. 개발된 ns급 펄스전원장치는 단위모듈을 기반으로 최대 펄스전압이 40 kV 까지 출력이 가능하며 이에 대한 상세설계 및 구현은 실험결과를 바탕으로 검증한다.

• Journal of Life Science
• /
• v.28 no.3
• /
• pp.369-375
• /
• 2018

Mycoplasma genitalium has 367 conserved genes and the smallest genome among mono-culturable prokaryotes. Conservative metabolic pathways were examined among M. genitalium and 14 prokaryotes, one hyperthermophilic exosymbiotic archaeon Nanoarchaeum equitans and 13 intracellular eubacteria of plants or insects, with fewer conserved genes than M. genitalium. They have 11 to 71 metabolic pathways, however complete metabolic pathways ranged from 1 to 24. Totally, metabolic pathway hole is very high due to the lack of 45.8% of the enzymes required for the whole metabolic pathways and it could be suggested that the shared metabolic pathway with the host's enzyme would work or the essential substances are host dependent. The number of genes necessary for mass transfer through the cell membrane is also very low, and it may be considered that the simple diffusion or the protein of the host will function in the cell membrane of these prokaryotes. Although the tRNA charging pathway was distributed in all 15 prokaryotes, each has 5-20 tRNA charging genes. This study would give clues to the understanding of the metabolic pathways of intracellular parasitic bacteria of plant and endosymbiotic bacteria of insects, and could provide basic data for prevention of crop damage, development of insect pests and human medicines.

• Korean Journal of Environmental Biology
• /
• v.20 no.2
• /
• pp.109-117
• /
• 2002

Detection of protozoan parasites Perkinsus sp. and P. atlanticus was developed in this study using a specific polymerase chain reaction (PCR) to diagnose the presence of those organisms that causes extensive mortalities of marine shellfishes. The PCR was conducted together with fluid thioglycollate medium (FTM) method and 2 M NaOH lysis method. For the test, Manila clams, Ruditapes philippinarum, were collected from four coastal locations in Korea including Wando Island, Gimnyeong, Sungsan and Sogwipo in Jeju. In addition, trophozites of Perkinsus sp. cultivated in vitro and the granular ark clam, Tegillarca granosa, taken from Gangjin on the south coast of Korea, were used as positive and negative controls, respectively. Expected DNA bands were detected in the samples from Wando Island, Sungsan and the in vitro cultured Perkinsus sp. when the probes specific for the genus Perkinsus and P. atlanticus were used. The samples were also positively diagnosed by the FTM and 2 M NaOH methods. In contrast, the Manila clams from Gimnyeong and Sogwipo, and the granular arks clams from Gangjin showed no detectable signs of infection with the PCR, the FTM method and the 2 M NaOH lysis method. On the other hand, being amplified by p. atlanticus specific primer, it is suggested that the protozoan parasite Perkinsus sp. found in the Korean Manila clam is P. atlanticus. Finally the PCR- based assay developed in the present study can be used in detection of Perkinsus infection and discrimination of Peykinsus species in quarantine stations or laboratories due to the high sensitivity and specificity as well as its rapid detection.