• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.571-574
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• 2013

To determine an efficient growth system for algal cultivation and to develop adequate culture system utilizing LED light, we investigated the effects of fluorescent and light emitting diode (LED) light source on the growth of Ulva pertusa. U. pertusa was cultured at $17^{\circ}C$ under a light intensity of 35 ${\mu}mol$ photons $m^{-2}s^{-1}$ and a 10L:14D photoperiod using either fluorescent or LED lamps. After 1 week of incubation under the same environmental condition, the length and width of Ulva pertusa grown under LED light were 1.5- and 1.9-fold greater, respectively, than the length and width of algae grown under fluorescent light. After two weeks, length and width were 2.6- and 2.0-fold greater, respectively, in algae grown under LED light. Total length and width of Ulva pertusa after three weeks of incubation were 1.7- and 1.2-fold greater in algae grown under LED light than those grown under fluorescent light. Therefore, the LED light induced significantly higher growth of Ulva pertusa than fluorescent light.

• Journal of Bio-Environment Control
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• v.12 no.2
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• pp.101-105
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• 2003

This experiment was conducted to find out the effect of day length on the production of high quality plug seedlings in onion (Allium cepa L.). Two cultivars, ‘Changnyongdaego’ and‘Wolryun’, were grown to seedlings in 200-cell plug trays under 11.5, 12.5, 13.5 hours and natural day length. These seedlings were transplanted to the pot (16 cm In diameter) and grown under 16 hours day length. Number of leaves and neck diameter showed better growth in the longer than shorter day length treatments, but plant height old sheath length were retarded in the longer day length treatments. Growth such as no. of leaves, neck diameter, plant height and sheath length increased with the passage of day, but plant height and neck diameter decreased by treatment over 20 days with 13.5 hours day length. Bulbing and bulb size of onion after transplanting were enhanced in the seedlings cultured under longer day lengths. From the above results, treatment of long day length during seedling culture in plug tray can control the overgrowth and produce high quality plug seedlings.

• Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.392-409
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• 2024

The present study aims to analyze the biological aspects and population dynamics of Indian mackerel in Barru waters. Data was collected in Barru for 11 months, from June 2022 to April 2023. The observed parameters of biological aspects included gonadal maturation stages (GMSs), size at first gonadal maturation, and length-weight relationship. Meanwhile, the aspects of population dynamics encompass age group, growth, mortality rate, and exploitation rate. Data analysis consisted of morphological selection of general maturation stages, Spearman-Kärber method in estimating gonadal first maturation size, Bhattacharya method in identifying age group, von Bertalanffy function through FISAT II to measure growth (L_∞ and K), Pauly Model to estimate mortality rate, Beverton & Holt Model to estimate Y/R, and virtual population analysis (VPA) analysis to estimate stock and fish yield. The results demonstrated that GMS I was observed to be dominant, followed by stages II and III. The initial gonadal maturation was estimated to be 17.98-19.28 cm (FL) for females and 17.98-19.27 cm (FL) for males. The length-weight relationship in male and female Indian mackerels indicated a positive allometric growth. The mode grouping analysis results from the fork length measurement revealed three age groups. It was also identified that the asymptotic length (L_∞) = 29.5 cm (fork length), growth rate coefficient (K) = 0.46 per year, and theoretical age at zero length (t₀) = -0.3576 per year. Total mortality (Z) = 2.67 per year, natural mortality (M) = 1.10 per year, fishing mortality (F) = 1.57 per year, and exploitation rate (E) = 0.59, the actual Y/R = 0.083 gram/recruitment, and optimal Y/R 0.03 gram/recruitment. Fishing mortality is higher than the natural mortality rate, and a high exploitation value (E > 0.5) also reflects over-exploitation. VPA analysis on fish yields and stock estimation reported a highly exploited rate between the 11.5 cm and 14.5 cm length classes and an exceeding current yield of 467.07 tons/year with a recommended yield of 233.53 tons/year to ensure population sustainability.

• The korean journal of orthodontics
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• v.23 no.3 s.42
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• pp.295-309
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• 1993

The purpose of this study was to investigate the effect of jaw growth in a growing rabbits, when they are subjected to refractive force and after removal of refractive force. The experimental animals were Oryctolagus couniculus, male rabbits of 4 weeks of age. The mandible is retracted with 200gm in force of each side to the posterior and superior direction for 14 hours a day. Then rabbits were used as control group. First experimental group received refractive force for 4 weeks. Second experimental group received for 8 weeks. Third experimental group received for 12 weeks. True lateral films and dorso-ventral films were taken before wearing appliances, 4 weeks, 8 weeks, 12 weeks and 16 weeks after wearing appliance. The changes of rabbits jaw growth were observed radiographically. The findings were as follows : 1. Mandibular refractive force decreased total mandibular length, mandibular condylar length and angular length. 2. Mandibular refractive force increased nasal height, condylar width and angular width. 3. Mandibular refractive force decreased mandibular lenght growth but increased mandibular width growth. 4. There is no phenomena of catch-up growth after refractive force removal.

• The Journal of the Korean bone and joint tumor society
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• v.17 no.1
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• pp.1-10
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• 2011

The main goals of treatment of malignant bone tumor are the prolongation of life survival and the improvement of quality of life. In growing children, however, leg length discrepancy (LLD) is one of major problem in the treatment of malignant bone tumors. Therefore, the precise understanding of growth in children is essential, and the prediction of LLD is critical in deciding the time and options of surgery. In addition, to use the adequate method of growth expectation, periodic follow-up and collaboration with patient's parents are needed.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.55 no.3
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• pp.146-152
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• 2006

In order to analyze the characteristics of series arcs that could happen in poor connections of electrical facilities, we made an apparatus which is similar to actual situation. series arcs are generated between copper and copper, copper and bronze, copper and brass, bronze and bronze, and then oxidation growth and voltage waveform were measured. A very small vibration with constant movement is needed to grow oxidation initially, whereas oxidation growth proceeded without a vibration after a certain amount of time. At first, blue white flame was generated initially between copper and copper, and then yellow flame was generated. In case of contact between copper and copper, the length of oxidation growth was about 7.1[mm] in 90[min]. In case of contact between copper and brass, the length of oxidation growth was about 4.3[mm] in 90[min], When bronze is contacted with copper, the lengths of oxidation growth were about 1.4[mm] in 20[min] and 2.7[mm] in 40[min] respectively, and no more oxidation growth was shown after that. In case of contact between brass and brass, the length of oxidation growth was about 1.2[mm] in 90[min], so it was the smallest compared to other cases. When copper is contacted with copper, the current through the load was about 1.6[A] and the power dissipation increased from 19[W] to 31[W]. In case of oxidation growth between copper and brass, the voltage changed from 8.4[V] to 11[V]. However, the voltage drop and the power dissipation between copper and brass were small compared to oxidation growth between copper and copper. When series arcs were generated between bronze and copper, a peak was shown at the beginning of voltage increase, and 40[min] later, oxidation material was not grown any longer. When oxidation growth occurred, voltage waveform showed irregular waveforms with tiny ripples.

• Ocean and Polar Research
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• v.39 no.4
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• pp.279-292
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• 2017

We determined the maturity and growth of the Marbled sole, Pseudopleuronectes yokohamae based on monthly sampling in the West Sea of Korea from February 2009 to December 2010. Determination of sex of P. yokohamae was by gonadal inspection, and age and growth were determined by analyzing the otolith. The biological minimum size of P. yokohamae female was 24.5 cm. The seasonal changes in the ratio of a translucent zone to an opaque zone revealed that the end of the translucent zone of the otolith were annuli formed in May once a year. We compared 8 type growth equations with several length-at-age data. By using the length-at-monthly age data of these, the calculated von Bertalanffy growth equations were $L_t=41.7(1-e^{-0.47(t+0.24)})$ for females and $L_t=32.7(1-e^{-0.75(t+0.01)})$ for males. We estimated that 24.5 cm was the total length of 2 year old P. yokohamae spawns in the cold water season from January to April, and grows to 8 years old for females and 6 years old for males in the West Sea of Korea.

• ALGAE
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• v.18 no.4
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• pp.289-294
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• 2003

The age growth pattern of Myagropsis mygroides (Cystoseiraceae, Phaeophyta)population were investigated at Tongyeong (128$^{\circ}$ 25' E and 34$^{\circ}$ 45' N) in South coast of Korea, from September 1998 to August 1999. Water temperatures varied from 7.7${^{\circ}C}$ to 26${^{\circ}C}$ during the survey period. Distinct seasonal changes were found in the plant legth and wet weight of plant, and their maximum length and wet weight were attained 70.5(${\pm}$ 20.9) cm and 191.8(${\pm}$ 135.0) g during April and May. The growth patterns were divided into four periods of slow growth (September-November), fast growth (December-February), maturing growth (March-May) and declining period (June-August). The Tongyeong population of M. myagroides was dominated by less than three-year old small plants with slower growth rates, shorter plant length, lighter plant weight than those of other locations in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.4
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• pp.232-238
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• 2005

This paper describes reproduction, population structure, growth and size at sexual maturity of a deep-water mud shrimp (Solenocera melantho) in the adjacent waters of Geomun Island, Korea. The shrimp was caught by a beam trawl from November 1998 to December 1999. Spawning period was estimated by gonadosomatic index to be from August to early November with a peak in October to early November. Female shrimps were $12\%$ matured at 16 mm in carapace length, $33\%$ matured at 18 mm and $75\%$ matured at 22 mm. The size at $50\%$ maturity for female was estimated to be 20.65 mm in carapace length. Breeding season was estimated to be from August to early November with a peak in October to early November. The size at $50\%$ inseminated was 19.81 mm CL. The fecundity was 87,500-405,200 and related exponentially to carapace length and total weight. This species survived between 25 and 26 months. The maximum carapace length of females and males were 48 mm and 34 mm respectively. Sex ratio was $51.3\%$, and the females were preponderant. Growth was estimated by modified von Bertalanffy growth function incorporating seasonal variation in growth in both years females (K=1.019/yr and $L_{\infty}$=51.731 mm CL) grew faster, reaching a larger size at a given age than males (K=1.848/yr, and $L_{\infty}$=27.499 mm CL). This is indicated by differences in growth performance indices $(\varphi')$ between females (3.291) and males (3.145).

• Journal of Ginseng Research
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• v.19 no.3
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• pp.287-290
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• 1995

This study was conducted to elucidate the effect of physical properties of soil in nursery bed with different densities on growth of ginseng seedling. Stem length, leaf length and leaf width of ginseng seedling showed the decreasing tendency with increasing the hardness of the nursery soil. Fresh root weight per seedling and number of available seedlings were increased significantly with decrease of the soil hardness. For solid, liquid phases, bulk density and hardness of soil, negative correlations were shown in stem length, leaf length, leaf width, root weight per seeding, and number t of available seedlings. On the other hand, gas phase, air permeability and porosity of soil had positive correlations with stem length, leaf length, leaf width, root weight per seedling and number of available seedlings. Key words Yang-Jik nursery, ginseng seedling, soil physical properties.