• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.879-891
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• 2012

The objective of this study was to evaluate seasonal patterns and diel variations of fish movements in the Juksan Weir which was constructed in 2010 at the down-stream of Yeongsan-River watershed. For this study, we monitored day-and-night movement(24 Hr cycle) and seasonal fish migration(June ~ August) patterns in 2011 along with species compositions and abundances depending on the locations of the traps within the fishway. Total number of species sampled was 14 and the total number of individuals was 1,263 with only the size-fractions(as total length) of the fish < 20 cm during the study. Seasonal analysis of fish movement in the fish way showed that highest frequency in the movement occurred in June - July, which is closely associated with a spawning peak season. The most dominant species using the fishway was Squalidus chankaensis tsuchigae, and this species turned out to be 26.9% of the total in the use rate of fishway. Daily monitoring of fish movements showed that most frequent movements occurred between 18:00 PM and 21:00 PM when the fish have a feeding time generally. The migratory fish were not found in the fishway during the study. Mean current velocity during the study $0.42{\pm}0.02ms^{-1}$(n = 42), and there were no significant statistical differences(p > 0.05) among the daily and monthly velocities in the fishway. The use rate of fish passage, in terms of fish species, was 48%, compared with total sampling of fish species(29 species) at the down-river regions during the same period, indicating a low use rate. Further continuous long-term monitoring should be conducted to evaluate the impacts of the weir construction in the river.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.12
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• pp.1750-1757
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• 2000

A total of 864 broiler chicks were used at Kansas State University and the University of Nebraska to determine the effects of heat treatment of two soybean genotypes on the growth performance. The soybeans were Williams 82 variety with (+K) and without (-K) gene expression for the Kunitz trypsin inhibitor. Heat treatment (autoclaving at $121^{\circ}C$ and $1.1kg/cm^2$) was applied for 0, 3, 6, 12, 18, and 24 min, resulting in a $2{\times}6$ factorial arrangement of treatments. Station and station treatment effects occurred, indicating that response in nutritional value of the soybean genotypes to heat treatment varied from year to year and location to location. However, the interactions were in magnitude of response rather than direction of response, with greater reductions in trypsin inhibitor concentrations for the soybeans heat processed at the Nebraska location. Pooled data indicated that -K supported greater (p<0.001) ADG, ADFI and gain/feed than the +K genotype. As the length of heat treatment increased, the ADG, ADFI, and the gain/feed ratio increased for chicks fed both soybean genotypes (p<0.0001). However, heating the -K soybeans resulted in a greater response in ADG, ADFI, and gain/feed than heating the +K soybeans (genotype heat treatment interaction, p<0.001). Pancreatic weights (mg pancreas/g of BW) of chicks fed -K soybeans were reduced compared to those from chicks fed +K (p<0.001). Increasing heat treatment decreased pancreas weights in chicks fed both soybean genotypes (p<0.001). Chicks fed heated soybeans in the Nebraska experiment had lower pancreatic weights than chicks fed heated soybeans in the Kansas experiment (station heat treatment interaction, p<0.0001). Chick growth performance was improved and pancreatic weights decreased by feeding raw -K soybeans versus raw +K soybeans, and by increasing heat treatment of both soybean genotypes. However, the response to heat treatment was not independent of genotype. Both +K and -K soybeans heated for 24 min supported similar ADG, ADFI, gain/feed, and pancreas weights, although chicks fed raw +K soybeans had lower growth performance than chicks fed -K soybeans. In conclusion, raw -K soybeans supported greater growth performance in broiler chicks than raw +K soybeans, although this advantage was lost when both soybean genotypes were heated for 24 min. Heat treatment of +K soybeans supported similar growth performance to heated -K soybeans, even though +K soybeans supported lower rates and efficiencies of gain than -K soybeans when fed raw.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.2 s.117
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• pp.151-157
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• 2007

We have presented a compact two-wire helical antenna adopted an open stub in opposite to a feeding point, which is for a T-DMB antenna of mobile devices. By adjusting the length of the open stub or pasting a dielectric material on the open stub, the input impedance around 200 MHz, bands of the T-DMB, can be easily control, even though the total height of the antenna is less than 8 cm(0.053 $\lambda$ at 200 MHz). The operating mechanism of the antenna is explained by using equivalent circuits of two modes, an unbalanced mode and a balanced mode. Based on the analysis of the equivalent circuits, the effects of using the open stub are validated. Several proposed antennas have been fabricated and measured. One of the fabricated antennas has -10 dB impedance bandwidth of $196{\sim}204$ MHz(8 MHz) whose value covers one channel of the T-DMB(6 MHz). The measured $S_{21}$ of the antenna is -38.6 dB which is about 17 dB higher than that of a monopole antenna whose height is same with the proposed antenna.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.500-507
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• 1998

Using a sledge net, the benthic amphipods were taken over one cycle of the neap and spring tides in January 1993 at the sandy shore surf zone of Dolsando, southern Korea. From these samples, we investigated the diel and tidal effects on the intraspecific zonation of Pontogeneia rostrata. The density of p. rostrata was higher during neap tide than spring. Of three categories (adult males and females and juveniles), juveniles and males attained to its highest density during neap and spring tides, respectively. Length- frequency data show that the high mortality of juveniles seemed to occur in winter. In the surface at night, it is significant that juveniles were significantly more abundant during neap tide than spring, whereas both adult males and females were more abundant during spring tide than neap. This suggests that the vortical migration patterns of juveniles and adults vary with the type of tides. During flood of spring tide, more than $90\%$ of population collected at the area above the mean sea level (MSL) were adults. With a decrease of female/male ratio, size of males increased there but that of female did not change, indicating an active migration of large males. This behavior can provide an extension of distribution area far large males, and also give a competitive advantage to large male against small one for mate and feeding. Although adult p. rostrata was collected at 100 cm above MSL at night during spring tide, a major portion of population as usually present on the shore below MSL. The center of zonation was restricted from 50 cm to 250 cm below MSL.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.682-692
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• 2007

This study presents an automatic system to predict parturition time in the crated sows. The system relies on ultrasonic transducers mounted from above along the length of the crate. Using a 40 kHz time of flight (TOF) single envelope wave, the momentary distances between the sensors are measured. Therefore, the local momentary height of the sow and the momentary posture, i.e. standing posture (SDP), kneeling posture (KP), sitting posture (STP) and lateral lying posture (LLP) are determined. Crated sows change their postures from standing to lying and vice versa which follows a characteristic pattern. As parturition approaches, sows exhibit uneasiness, restlessness and the stand up sequence (SUS, the posture transition from LLP to SDP) rate increases because of labor pains. In time series, the SUS rate demonstrates a peak and it happens approximately 0-12 h before parturition. In this paper, the basic parturition threshold value method (BPTVM) and the same hour method (SHM) are proposed for predicting parturition, both of which are based on the SUS rate. The BPTVM mainly detects the peak of the SUS rate. As the SUS rate exceeds the threshold value, the parturition becomes predictable. Moreover, the SHM calculates the difference in the SUS rates between a particular time of day and the corresponding time of the preceding day. Compared to the BPTVM, the SHM can eliminate the circadian rhythm of the SUS rate influenced by feeding behavior. Using the SHM the parturition can be approximately predicted within hours. In an attempt to define the threshold parameters of predicting parturition, a data set with 32 sows of the SUS rate are used to estimate assumable predicting probability. The results show the assumable probability of the parturition prediction within 9 h is 96.9% for the SHM and 84.4% for the BPTVM. Moreover, the SHM can even reach a 75% probability of prediction within three hours of parturition. We conclude that the SHM is more accurate and is more useful for parturition time prediction. When parturition is detected, the proposed algorithm generates a warning signal which can inform human personnel to protect the mother and newborn piglets.

• Journal of Aquaculture
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• v.7 no.2
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• pp.77-87
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• 1994

The study was conducted to develop the suitable abalone's diets for the indoor tank culture. The young abalone Haliotis discus hannai Ino sized ca. 20, 30 and 40 nun in shell length were fed three different diets, dried sea mustard Undaria pinnatifida HARVEY (control), artificial diet and terrestrial plants e. g. Chinese cabbage and Perilla leaf for 2 years. The growth rate of abalones fed an artificial diet was slightly higher than that of abalones from the control. However, the growth rate of abalones from terrestrial plants was significantly lower than that of abalones fed a control or an artificial diet (P< 0.05). The daily feeding rate of young abalones from terrestrial plants was slightly higher than that of abalones from the control. While, that of abalones from an artificial diet was approximately $30\%$ of that of abalones from a control or a terrestrial plants diet. The feed efficiency of abalone from artificail diet was higher than that of abalones from a control or a terrestrial plants diet, and the smaller size of young abalone showed the higher the feed efficiency. The EFA index values ${{\sum}n9/(20:4n6+20:5n3+22:6n3}$ of the dried sea mustard and the artificial diet were 1.26 and 3.64, respectively. These values were favorable, but the value of terrestrial plant, Perilla leaf was 127.00 indicating poor EFA index for normal growth of abalone.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.148-148
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• 2011

Recently, there have been many research activities to develop the large-area plasma source, which is able to generate the high-density plasma with relatively good uniformity, for the plasma processing in the thin-film solar cell and display panel industries. The large-area CCP sources have been applied to the PECVD process as well as the etching. Especially, the PECVD processes for the depositions of various films such as a-Si:H, ${\mu}c$-Si:H, Si3N4, and SiO2 take a significant portion of processes. In order to achieve higher deposition rate (DR), good uniformity in large-area reactor, and good film quality (low defect density, high film strength, etc.), the application of VHF (>40 MHz) CCP is indispensible. However, the electromagnetic wave effect in the VHF CCP becomes an issue to resolve for the achievement of good uniformity of plasma and film. Here, we propose a new electrode as part of a method to resolve the standing wave effect in the large-area VHF CCP. The electrode is split up a series of strip-type electrodes and the strip-type electrodes and the ground ones are arranged by turns. The standing wave effect in the longitudinal direction of the strip-type electrode is reduced by using the multi-feeding method of VHF power and the uniformity in the transverse direction of the electrodes is achieved by controlling the gas flow and the gap length between the powered electrodes and the substrate. Also, we provide the process results for the growths of the a-Si:H and the ${\mu}c$-Si:H films. The high DR (2.4 nm/s for a-Si:H film and 1.5 nm/s for the ${\mu}c$-Si:H film), the controllable crystallinity (~70%) for the ${\mu}c$-Si:H film, and the relatively good uniformity (1% for a-Si:H film and 7% for the ${\mu}c$-Si:H film) can be obtained at the high frequency of 40 MHz in the large-area discharge (280 mm${\times}$540 mm). Finally, we will discuss the issues in expanding the multi-electrode to the 8G class large-area plasma processing (2.2 m${\times}$2.4 m) and in improving the process efficiency.

• Ocean and Polar Research
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• v.25 no.2
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• pp.213-226
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• 2003

Kongsfjorden near Korean Arctic Station, Dasan, is a glacial fjord in the Svalbard archipelago, Arctic that is influenced by both Atlantic and Arctic water masses. During the Arctic field season August 2002, surface temperature, salinity, density, and phytoplankton biomass (chi a) was measured in Kongsfjorden. A total of 15 surface samples were collected for the phytoplankton related measurements. Chl a values ranged from 0.08 to 1.4mg chi a $m^{-3}$ (mean of 0.53mg chl a $m^{-3}$) in the overall surface stations. The highest values of the chi a concentrations (> 1.0mg chi a $m^{-3}$) were found near glacier in the northeastern part of Kongsfjorden. Nanoplanktonic (< $20{\mu}m$) phytoflagellates were important contributors for the increase of the chi a. The nano-sized phytoflagellates accounted for more than 90% of the total chi a biomass in the study area. Surface temperatures and salinities ranged from 2.5 to $7.18^{\circ}C$ (mean of $4.65^{\circ}C$) and from 22.55 to 32.97 psu (mean of 30.16 psu), respectively. The physical factors were not highly correlated with phytoplankton distribution. The character of surface water due to down-fjord wind was highly similar to phytoplankton distribution. Drifting ice, freshwater, and semdiment inputs from large tidal glaciers located in the inner part of Konsfjorden create steep physico- and biogeochemical environmental gradients along the length of this ford. The glacial inputs cause reduced biodiversity biomass and productivity in the pelagic community in the inner fjord. Primary production of benthic and pelagic microalgae is reduced due to the limited light levels in the turbid and mixed inner waters. The magnitude of glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground fer marine mammals and seabirds. Especially, seabirds play the largest energy intake and also export nutrients for primary production of the marine microalgae. Kongsfjorden has received a lot of research attention as a site for exploring the impacts of climate changes. Dasan Station in Kongsfjorden will be an important Arctic site for monitoring and detecting future environmental changes.

• Korean Journal of Ichthyology
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• v.10 no.1
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• pp.32-39
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• 1998

Structures of jaw bones, gill rakers and pharyngeal bones of the three Pomadasys species collected from Arafura sea of Indonesia in May 1996 were described and illustrated to compare between species. The percentage of ascending process of premaxillary to head length was 21.6~23.3% in Pomadasys kaakan, 25.4~27.8% in P. maculatus and 15.3~21.0% in P. argyreus. The percentage of ascending process of premaxillary to premaxillary was 54.7~72.8% in P. argyreus, 107.8~114.9% in P. kaakan and 126.7~136.7% in P. maclllatlls. The ascending process of premaxillary of P. argyreus showed a tendency to increase as fish grow. Each jaw in all three grunters had a row of conical teeth exteriorly, but 1 to 5 rows of niddle like teeth interiorly. Among the three species examined, P. maculatus showed the most developed teeth. Pharyngeal bone, appeared to be stronger than jaw teeth, contained dense needle like teeth in P. argyreus, where as that in P. kaakan and P. maculatus had long and slender teeth exteriorly but thicker interiorly. Gill rakers of P. kaakan and P. maculatus are short, but those of P. argyreus are long.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1080-1087
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• 2004

A trial with twenty-four newly weaned Awassi lambs (initial body weight=21.5$\pm$0.8 kg) was conducted using a 3$\times$2 factorial design to study the effect of feeding three sources of protein supplements (soybean meal (SBM), sunflower seed meal (SSM), and cottonseed meal (CSM)), either untreated or formaldehyde-treated on the growth performance and carcass traits of Awassi lambs. Lambs were randomly assigned to one of the six diets (4 lambs/treatment diet) and were individually fed for a period of 107 days. Experimental diets were isonitrogenous and isocaloric. Final live weight and average daily gain (ADG) were affected by both source of protein and formaldehyde treatment (undegradable protein). Lambs fed untreated diets had better (p<0.01) daily gain compared to those fed formaldehyde-treated diets. Similarly total feed intake per animal was significantly (p<0.05) affected by protein source and formaldehyde treatment. Formaldehyde treatment caused a significant decrease (p<0.01) in feed intake compared to lambs fed untreated diets. Feed requirement per unit of gain was not affected by formaldehyde treatment during all periods of the experiment except for the second period (the second 28 day period), whereby untreated SBM, SSM and CSM had better feed conversion ratio (FCR) than the treated groups. Source of protein had a moderate effect (p<0.10) on FCR but had a significant effect (p<0.05) on hot and cold carcass weight, digestive tract empty weight and liver weight, with lambs fed SBM having higher values than lambs fed SSM and CSM diets. Supplementation with undegradable protein had a significant effect (p<0.05) on dressing-out percentage (p<0.05), final live weight, and hot and cold carcass weight (p<0.01). The lower values pertain to lambs fed treated diets compared to lambs fed untreated diets. In general, there were no significant differences among all carcass linear dimensions, carcass cut weights and dissected loin tissue weights for both treatments (protein source and formaldehyde treatment). Supplementation with undegradable protein but not the source of protein resulted in significantly higher dissected leg total bone weight (p<0.05), tibia and femur weight (p<0.05), and femur length (p<0.01) at the same carcass weight. Results suggest that the treatment of SBM, SSM and CSM with formaldehyde did not improve efficiency of feed utilization, lamb performance or carcass traits and that the SBM diet resulted in an increase in lamb performance compared to other experimental diets.