• Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.342-349
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• 2009

The purpose of the current study was to optimize shrimp-pot design to allow greater control over the size of captured individuals for the purposes of shrimp resource management. Tank experiments were conducted to determine the optimal slope length and slope angle by analyzing the sizes of shrimp that entered 25 model pots with combinations of five different slope lengths and five different angles. Shrimp size was measured using carapace length. The results showed that as the slope angle of the pot increased, the size of individuals that entered the pot increased. Furthermore, as the slope length increased, each of the five different slope angles of the pot increased, and the size of individuals entering also increased. The data indicated that the optimum pot design for reducing the capture of immature individuals had a $75^{\circ}$ slope angle and a 35.4 cm slope length.

• Journal of Ocean Engineering and Technology
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• v.36 no.2
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• pp.125-131
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• 2022

Structural design for shipbuilding is generally divided into three stages: the basic, detailed, and production designs, of which the production design is the most frequently revised among the three design stages. The revision involved in production design department was approximately 61% of the total 4,211 revision members and approximately 56% of the total 710 revision cases in the survey on the number of design revisions for nine ships. In this study, members and drawings with a high revision rate were investigated, and related design departments were identified. In addition, the work contents of the design department were analyzed to reduce the number of design revisions and three tasks are very frequently revised were selected. A survey was conducted with engineers engaged in the production design, after which, standards were proposed for the method of aggregating bills of materials, to employ macros to calculate the length of members and that of profile input data when reviewing drawings. Via the study, it was determined that the major causes of design revision are simple mistakes by engineers or lack of understanding on structural arrangement of basic members more than intricacies of prior design and high level specification. As a result of applying the proposed standards, it was confirmed that the design revision was reduced by approximately 40%.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.3
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• pp.213-220
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• 2005

Penetration and health effect of fibers was related with their diameters and length. The purpose of this study is to characterize and compare the diameter and length of airborne man-made mineral fibers(MMMF) or synthetic vitreous fibers in the related industries. The average fiber length of the continuous filament glass, rock wool, refractory ceramic, and glass wool fibers production industries approximately 27, 28, 35, $50-105{\mu}m$. Airborne glass fibers were longest in all the type of MMMFs. The average diameters of airborne fibers generated from refractory ceramic, rock wool, glass wool, continuous filament glass fibers production industries were approximately 1.0, 1.6, 1.5-4 and $10{\mu}m$, respectively. The percentages of respirable fibers(<$3{\mu}m$) were 94% for RCFs, 73% for rock wool fibers, 61.0% for glass fibers, and 1.6% for filament glass fibers. The length of glass fibers were the longest in all types of fibers, and length of the others were similar. The refractory ceramic fibers were smallest in diameters and highest in fraction of respirable fibers.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1565-1571
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• 2003

Physiological mechanisms, involved in unusual ovulatory sequences in domestic hen are remaining undefined. One hundred individually caged white leghorn birds were divided into two equal groups viz. control and treatment, and 2-bromo-$\alpha$-ergocryptine, was administered to birds in the treatment group to modulate prolactin (PRL) secretion from anterior pituitary gland. The effect of modulation of PRL concentrations on egg production, sequence length and intersequence pause length were studied by analysis of oviposition records of the birds from 24 to 72 weeks of age. The surviving 48 birds in the control and treatment groups averaged $34.58{\pm}1.7$ and $25.67{\pm}1.15$ sequences of oviposition, with a mean sequence length of $9.92{\pm}0.63$ and ${\pm}1.12$ days respectively. Most of the birds had a single characteristically long sequence during the entire reproductive cycle, which averaged $46.04{\pm}3.09$ days in the control birds and $59.33{\pm}4.44$ days in the treated birds. 2-bromo-$\alpha$-ergocriptine treatments had significantly decreased (p$\leq$0.01) the circulating concentrations of PRL compared to the birds of the control group. This resulted in a significant increase (p$\leq$0.01) in the number of laying days in birds of the treatment group with a concomitant decrease in the intersequence pause length. The decreased PRL levels during prime sequences in birds of the both groups, reveals the negative role of the circulating PRL levels on egg production with concomitant shorter intersequence pause length. Hence, modulation of PRL with dopamine agonist may enhance the reproductive efficiency of hens later in life.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.206-215
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• 2005

Polyhydroxyalkanoates (PHAs) are homo or hetero polyesters of (R)-hydroxyalkanoates accumulated in various microorganisms under growth-limiting condition in the presence of excess carbon source. They have been suggested as biodegradable substitutes for chemically synthesized polymers. Recombinant Escherichia coli is one of the promising host strains for the economical production of PHAs, and has been extensively investigated for the process development. The heterologous PHA biosynthetic pathways have been established through the metabolic engineering and inherent metabolic pathways of E. coli have been redirected to supply PHA precursors. Fermentation strategies for cultivating these recombinant E. coli strains have also been developed for the efficient production of PHAs. Nowadays, short-chain-length (SCL) PHAs are being re-invited due to its improved mechanical properties and possible applications in the biomedical area. In this article, recent advances in the development of metabolically engineered E. coli strains for the enhanced production of SCL-PHAs are reviewed. Also, medical applications of SCL-PHAs are discussed.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.6
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• pp.82-91
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• 2002

This study was conducted to investigate methods to overcome serious problems in hedge making. The growth response of Enonymus japonica was investigated, using different sizes of nonwoven fabric containers. Changes of shoot length, fresh weight and chlorophyll contents were measured a period of growth in each size of container. The results of this study are as follows; 1) The maximum growth of shoot length in all treatments was observed in May and August. The significant difference was found in the smaller size of container containing a less amount of soil than the control. 2) The soil amount of rhizosphere for the production of a standardized hedge seemed to be over 2,400-3,600㎤ per plant. 3) The depth of containers had a greater influence on growth of shoot length than the width of containers. 4) The fresh weight in 40cm width containers and 30$\times$20cm containers was similar to the control, but the rest of the containers showed significant difference compared with the control. 5) A significant difference of chlorophyll content was found in A, B, C, D and G treatment but I treatment did not show significant difference at the 5% level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.3
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• pp.302-309
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• 2024

This study estimates the target strength of anchovy Engraulis japonicus required for studying their distribution and density using acoustics and evaluates the acoustic scattering characteristics of anchovies by frequency using the Kirchoff ray mode (KRM) model. The experiment was conducted on 30 anchovies with 4.7-21.5 cm total length. The maximum TS_cm (Simming angle, 9.1°; standard deviation, ± 13.1°) according to total length was -66.9, -65.2, -64.4, and -63.4 dB at 38, 70, 120, and 200 kHz, respectively. The average TS_cm (Simming angle: 9.1°, standard deviation: ± 13.1°) according to total length was -68.9, -68.8, -69.6, and -70.0 dB at 38, 70, 120, and 200 kHz, respectively. The results of this study provide an important basis for future studies that use acoustics to estimate the target strength of anchovies.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.3
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• pp.219-221
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• 1995

Data on productive and reporductive performance of native cows maintained at Savar Dairy Farm, Central Cattle Breeding Station (CCBS), Savar, Dhaka, were collected from the periods of 1980-1988. The mean calving to first breeding during the second parity was longer (p < 0.01) than the fourth and fifth parities (152 vs 105 and 96 days respectively). There was no difference on the parameters like first breeding to conception, service period, gestation length, number of services per conception and total milk yield over the parities. The mean calving interval during the second parity was longer (p < 0.05) than the fourth and fifth parities. The mean lactation length during the first parity was longer (p < 0.01) than those of second, third, fourth and fifth lactations (317 vs 237, 266, 250 and 247 days respectively). The mean per day milk yield during the first lactation was lower (p < 0.01) than those of second, third, fourth and fifth lactations (1.88 vs 2.55, 2.75, 2.54 and 2.57 kg respectively). The mean dry period was longer in first lactation (p < 0.05) compared to third and fifth lactations (209 vs 141 and 129 days respectively).

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.135-138
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• 2011

In traditional organic rice culture practices, control of weeds is a big problem. This study was conducted to increase the rice production. Results showed that Plant height, SPAD, root length and weight were higher in pot raised seedling than broadcasting method except number of panicles. High plant density caused reduction in plant height, number of culm and chlorophyll content of the rice. No lodging was observed in both methods. Thickness of third internode and culm length was more in pot raised seedlings at both sites. When organic material was used rice yield increased by 3.81%. Higher rice production (10%) was recorded in the fields planted with pot raised seedlings. From the above study it could be conclude that the pot raised seedlings perform better than the seedlings raised by broadcasting methods.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.2
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• pp.119-122
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• 1995

A total of 6 tamaraws were observed for determining coat color and measured for body conformation. Banding pattern of 4 blood proteins and 2 isozymes were analysed from the peripheral blood of two tamaraws. The coat colour of younger tamaraws were observed to be brown and adult was found to be complete black. The body weight, body length, withers height, head length, head width, horn length and tail length of adult male and female tamaraws were: 236 kg and 208 kg; 113.5 cm and 112.5 cm; 19.5 cm and 20 cm; 30.0 cm and 28.5 cm and 36.0 cm and 35.5 cm, respectively. The electrophoretic banding pattern, distance migrated and the allelic frequencies obtained in tamaraws were similar compared with that reported in swamp buffaloes. Although the sample size was very small, results of this study could be an important source of informations based on which a breeding programme can be designed to exploit some of the economic characters of tamaraw.