• Transactions of Materials Processing
• /
• v.22 no.8
• /
• pp.486-491
• /
• 2013

A numerical investigation of the butting process for an AZ31B magnesium alloy tube at elevated temperatures was conducted to develop a double-butted magnesium alloy tube. As a result of the current study, it was found that the amount of doming of the tube end, prior ironing-extrusion to obtain high wall thickness reduction are important factors for the butting process of magnesium alloy tubes. There is also a limitation of the thickness profile of butted tube due to buckling of tube wall during the stripping stage.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.9 no.6
• /
• pp.1581-1584
• /
• 2008

In dual-polycide-gate structure with butting contact, net doping concentration of polysilicon was decreased due to overlap between $n^+$ and $p^+$ and lateral dopant diffusion in silicide/polysilicon layers. The generation of parasitic Schottky diode in butting contact region is attributed both to the $CoSi_2$-loss due to $CoSi_2$ agglomeration and to the decrease in net doping concentration of polysilicon layer. Parasitic Schottky diode reduces noise margin of sense amplifier in DDI DRAM, which causes column fail. The column fail could be reduced by physical isolation of $n^+/p^+$ polysilicon junction or suppressing $CoSi_2$ agglomeration by using nitrogen implantation into $p^+$ polysilicon before $CoSi_2$ formation.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.2
• /
• pp.485-490
• /
• 2010

We propose the equivalent circuit model including all parasitic components in input gate of sense amplifier of DDI DRAM with butting contact structure. We analysed the effect of parasitic schottky diode by using the proposed model in the operation of sense amplifier. The cause of single side fail and the temperature dependence of fail rate in DDI DRAM are due to creation of the parasitic schottky diode in input gate of sense amplifier. The parasitic schottky diode cause the voltage drop in input gate, and result in decreasing noise margin of sense amplifier. therefore single side fail rate increase.

• Korean Journal of Animal Reproduction
• /
• v.9 no.2
• /
• pp.140-147
• /
• 1985

Seventy four Holstein heifers were randomly assigned over three trials to PRID-7+PG-6 and Synchromate B-9 regimens to synchronize estrus cycle for embryo transfer. Sexual behaviors; moounting, standing, orientation, chin-resting, sniffing, licking, rubbing and butting, vaginal swelling and mucus discharge were observed between 06-08, 12-14 and 18-20 h on 1st day and 00-02, 06-08, 12-14 and 18-20 h on 2nd day after removal of hormones. Synchromate-B treatment (81.6%) showed higher synchronized estrus rate than PRID treatment (77.8%) during observation period. Standing estrus was observed within 74 h after PG injection in PRID and within 52 h after removal of implant in Synchromate-B. About 68% of heifers in PRID and 74% of heifers in Synchromate-B showed standing estrus between 0-14 h on 2nd day after removal of the hormones. Synchromate-B resulted in a tighter synchrony of standing estrus than PRID. Incidence of average mounting and standing per head during observation period was 22.3 and 16.6 in PRID and 28.1 and 13.6 in Synchromate-B. The PRID showed peak in active mounting at 18-20 h on 1st day, however, the Synchromate-B showed at 0-2 h on 2nd day after removal of hormone. Active standing was shown between 18 h on 1st day to 20h on 2nd day in PRID, however, between 0-14 h on 2nd day after removal of hormone is Synchromate-B. There was slight difference in pattern of active mounting and standing during estrus between PRID and Synchromate-B. Conception rate of synchronized heifers transferred with fresh and frozen embryos by non-surgical and surgical methods was higher in synchromate-B (62.5%) than in PRID (38.5%). Chin-resting showed highest incidence among 6 sexual behavioral components in the both treatments. Synchromate-B showed higher incidence of chin-resting (16.6) than PRID (10.7). Synchromate-B group showed also higher incidence of orientation, sniffing and butting than PRID group. Synchromate-B resulted in more active sexual behaviors than PRID. The pattern of incidence of chin-resting, licking and butting was almost symmetrical in PRID with their peak values at 6-8 h on 2nd day, however in Synchromate-B chin-resting and sniffing was symmetrical with their peak values at 12-14 h on 2nd day after removal of hormone. There was tendency to increase vaginal swelling according to time passage of synchronized estrus in the both treatments. Incidence of mucus discharge in Synchromate-B was slightly higher than in PRID. Twenty to 40% was false negative in conception rate by tall painting before re-estrus day as judged by rectal palpation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1995.10a
• /
• pp.361-364
• /
• 1995

Wavelet Transform is a new tools for signal processing, such as data compressing extraction of parameter for Reconition and Diagnostics. This transform has an advandage of a good resolution compared to Fast Fourier Transform (FFT) In this study, we employ the wavelet transform for analysis of Acoustic Emission raw signal generated form rotary compressor. In abnormal condition of rotary compressor, the state of operating condition can be classified by analizing coefficient of wavelet transformed signal.

• Korean Journal of Ichthyology
• /
• v.18 no.3
• /
• pp.193-201
• /
• 2006

We researched the reproductive ecology of pale chub, Zacco platypus that inhabits Gajeong-cheon and Wonju-cheon that are a tributary to the Han river. The nuptial organ was formed on the head part, the anal fin and the tail part in male, the change of nuptial color was outstanding. By their changing body shape, the anal fin was extended and body depth came to be high during the spawning season in both sexes. Territorial male of defending behavior were head butting, rotated fighting, parallel swimming, biting and expelling. After pale chub located himself from the upper of the female that was approached to the side parallelling with the female, male and female spawned digging sand with their anal fin by vibrating and any parental care of the eggs was not taken. The spawning interval and lasting time were relevant to individuals density of spawning ground.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1995.10a
• /
• pp.365-368
• /
• 1995

Rotary Compressor has many AE(Acoustic Emission) sources according to condition of parts because it is operated with combination of various parts. In this study, analysis of AE raw signal generated form Rotary compressor which artificially-made parts inflicted abnormal condition was carried out. AE raw signals were acquired form high-speed A/D board, and many burst type signals were observed. By analyzing burst type signals which is caused form internal AE source,efficient AE parameters for monitoring and diagnosis were presented.

• Proceedings of the KIEE Conference
• /
• 1987.07b
• /
• pp.1463-1466
• /
• 1987

The problem of generating minimal area CMOS functional cell layout can be converted to that of decomposing the transistor connection graph into a minimum number of subgraphs, each having a pair of Euler paths with the same sequence of input labels on the N-graph and P-graph, which are portions of the graph corresponding to NMOS and PMOS parts respectively. This paper proposes a heuristic algorithm which yields a nearly minimal number of Euler paths from the path representation formula which represents the give a logic function. Subpath merging is done through a list processing scheme where the pair of paths which results in the lowest cost is successively merged from all candidate merge pairs until no further path merging and further reduction of number of subgraphs are possible. Two examples were shown where we were able to further reduce the number of interlaces, i.e., the number of non-butting diffusion islands, from 3 to 2, and from 2 to 1, compared to the earlier work [1].

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.11a
• /
• pp.328-332
• /
• 1996

The compressor is one of important elements in refrigerator cycle and play an important role of refrigeration efficiency and quality. Therefore it is very important to monitor state of normal and abnormal compressor. In this research, technic of AE is used for monitoring abnormal rotary compressor and an AE parameter which is a most proper parameter to monitor the abnormal state of compressor is determined by signal processing, Finally, the monitoring result of rotary compressor is agreement with the result of life test.

• Journal of Embryo Transfer
• /
• v.26 no.2
• /
• pp.141-145
• /
• 2011

Seven male Himalayan tahrs were strongly assumed to have accidently fed on foreign bodies in 2007. At the time, zoo caretakers witnessed missing fence padding, such as carpet, plastic awning, and ropes. The incident occurred the morning after the items had been set up to protect indigenous, wild long-tailed gorals from self injury caused by head butting the steel fence. Adult male Himalayan tahrs were obviously suspected of mostly eating the paddings mainly composed of carpet, thin and long plastic awning, and ropes. Even though they had not shown digestive problems, surgery was determined necessary in order to remove any indigestible foreign bodies. Left flank rumenotomy was conducted on seven male Himalayan tahrs from April to May, 2011. After anesthesia with xylazine, rumenotomy was performed on a concrete floor, with legs and head secured by ropes. No access to water and hay prior to operation for two days was needed to make the surgical procedure done quickly. Two sheets of small hand towels protecting against inflow of ruminal contents were beneficial during surgery. Antibiotics were administered intramuscularly for seven days. No abscesses at the surgical site were found after surgery. Like domestic ruminants, wild ruminants also ingest metalic or non-metalic, indigestible foreign bodies by accident. Therefore, simplified rumenotomy must be developed to apply to those wild animals to lengthen their longevity and to advance the quality of life in captivity. This case report is the first showing how to perform rumenotomy of Himalayan tahr, a wild ruminant, in Korea.