• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.63-70
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• 1969

1. This paper deals with the natural mortality of the early young bivalve, Meretrix lusoria, (less than 13mm in shell length) and the perforations bored in the bivalve by bering snails, Neverita didyma and Natica severa. The investigation was carried out in the Kunsan area and in the laboratory from May to October of 1968. 2. The natural mortality of the field population during this period was $12.1\%$ and among this number $38.1\%$ were drilled by boring snails. 3. The common species of the Naticid gastropods, boring snails-Neverite didyma and Natice severa - are encountered in the habitat of M. lusoria. The perforations drilled by these species were broadly bevelled. 4. The location of the holes on the valves varied widely, while most of holes on the valves were located at a relatively definite umbo position. 5. The inner and outer diameters of the holes varied in proportion to the shell length of the clam; each ranging in shell length from 1 to 3mm, 3 to 6mm, and 6 to 13mm, and the outer diameters were 0.4-0.5mm, 0.7-0.9mm and 0.9-1.2mm. On the other hand, the ratio of the inner and outer diameters differed in proportion to the shell length of the clam. 6. Predation rates of Neverita didyma was much greater at night than during the day at room temperature. An average of 1.7 young clams was drilled and consumed, per snail, per day. This rate was greater than that of the Natica severa. 7 Predation rates varied in proportion to the shell length of the clam and the shell height of the snails.

• Korean Journal of Ichthyology
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• v.13 no.1
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• pp.74-84
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• 2001

The early developmental stages, growth and morphological changes of the Korean bullhead, Pseudobagrus fulvidraco, were studied from a series of reared specimens. Details of the early developmental stages are illustrated with special reference to morphological transformations. Egg and sperm of Korean bullhead were obtained from mature adults under hormonal treatment, fertilized artificially, and incubated in the aquarium. The incubation period of fertilized eggs was 55 to 66 hours at a temperature of 24.9${\pm}$0.34$^{\circ}$. Larvae were fed successively with Artemia salina and Daphnia magna for 2 to 15 days and artificial food after 20 days. Fertilized eggs were adhesive and spherical with a diameter of 2.04mm(n = 100). The mean total length of newly hatched larvae was about 4.92${\pm}$0.33 mm. Mouth opening occurred on one-day-old yolk-sac larvae, and initial feeding was observed on the third day after hatching. The morphological transitions from larvae to juvenile and juvenile to young stages occurred when the fish reached about 17 mm in total length (about 13days after hatching) and about 32 mm in total length (about 30 days after hatching), respectively. Many changes in proportion of body parts to total length were observed at about 7~8 mm and 30~32 mm, corresponding to the transformations from larvae to juvenile and from juvenile to young, respectively. In comparing relative growth of each body part against total length, those characteristics related to head parts showed positive growth in the pre-larval stages, while those concerning mobile abilities showed positive growth in the post-larval stage.

• Korean Journal of Ichthyology
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• v.31 no.3
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• pp.131-140
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• 2019

This study is to observe species identification and early life history of Gnathopogon strigatus and to use it as a basis for taxonomic studies and conservation of species. For the experiments, the mature adults were collected at the Wang-suk Stream located in Namyang-ju city, Gyeong-gi Province and eggs were artificially fertilized by the wet method in the laboratory. The shape of the fertilized egg was globular, adhesive, opaque white in color and had no oil globules. The fertilized egg was 1.66~1.88 mm (average 1.76 mm, n=30) in diameter. The blastular stage occurred at 3 hours 05 minutes after fertilization and the gastrular stage was detected at 8 hours 30 minutes after fertilization. The embryo began to hatch about 54 hrs after fertilization under water temperature of $23{\pm}1^{\circ}C$ and the newly hatched larva (yolksac larva) were 4.1~4.7 mm (mean 4.4 mm, n=20) in total length (TL). The fourth day after hatching, the postlarva were 5.4~5.9 mm (mean 5.6 mm, n=20) in total length, their york sacs were completely absorbed and Start eating Artemia sp. Ten days after hatching, flexion larva were begins Notochord flexion were 7.5~8.6 mm (mean 8.1 mm, n=20) in total length. Sixteenth day after hatching, postflexion larva were complete Notochord flexion were 8.2~9.7 mm (mean 9.1 mm, n=20) in total length. At thirty-eight days after hatching, Juvenile were arrive integer all fin rays and similar to those of adults were 11.3~15.5 mm (mean 13.3 mm, n=20) in total length.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.3
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• pp.181-189
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• 2004

The purpose of this study was to investigate the effects of sleep/wake behavior for shift workers in the iron and steel industry using wrist actigraph for 59 male workers on a continuous full-day three-team three-shift system of backward rotation including on-duty and off-duty periods. The wrist actigraph data were recorded for 15 days (l shift cycle) for each subject. The sleep length at home during night shift decreased significantly as compared to the morning or evening shifts. The night shift nap length increased significantly in all sections as compared to the morning or evening shifts. The nap length in the Steel Manufacturing Process and Rolling Process during night shift decreased significantly as compared to the Machine Maintenance Section, the Forwarding of Products Section, and the Field Management Section. However, the sleep length at home while off-duty period increased significantly. The percentage of nap length during night shift in the Rolling Process, Steel Manufacture Process, and the other three types of jobs was 16.0%, 20.4%, and about 50.0%, respectively. The nap length during night shift for the above 50 year olds increased significantly as compared to the below 50 year olds. Finally, we discussed the role of nap-taking during the burden on night shift workers and the increased difficulty in continuing their job.

• The Journal of Pediatrics of Korean Medicine
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• v.23 no.1
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• pp.141-158
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• 2009

Objectives The purpose of this study is to find out the effect of KyungOcGogamibang(KOGE) on the growth of rats. Methods First of all, we divided male Sprague-Dawley rats into 4 groups(KOGE1, KOGE2, KOGE3 and control group). Then KOGE1, KOGE2 and KOGE3 groups were administered with KOGE water extracts once a day at a dosage of 250, 500, 1,000mg/kg respectively for 3 weeks. The control group was administered with normal saline in the same manner. We measured the rat's body weight, amount of body weight increased, length of femur, serum GH, serum IGF-Ⅰ, serum TSH and serum testosterone after each week of administration. Results 1. There were significant changes of the rat's body weight, the length of the femur, the level of GH, IGF-Ⅰand TSH in KOGE1 groups. 2. There were significant changes of the rat's body weight, the length of the femur, the level of IGF-Ⅰand TSH in KOGE2 groups. 3. There were significant changes of the rat's body weight, the length of the femur, the level of IGF-Ⅰand TSH in KOGE3 groups. Conclusions According to the results above, rat in KOGE group have been increased their body weight, length of femur, serum GH, serum IGF-1 compared to the control group. This study shows that groups of KOGE have an effect on promoting the growth, thus it is expected to treat growth problems for children.

• Korea Journal of Hospital Management
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• v.9 no.3
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• pp.128-142
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• 2004

To evaluate the effects of critical pathway on the length of hospital stay, the cost and quality of care provided to gastrectomy patients in a tertiary care academic medical center. The basic research design is a retrospective case-control comparative study. 470 patients of gastrectomy were included in the study; 180 before pathway development (control), 163 right after pathway implementation (path group I) and 127 one year after pathway implementation (path groupII). 476 patients of modified radical mastectomy were also analyzed to examine whether the reduction of the length of hospital stay is from the hospital-wide trend or due to the critical pathway. Death after operation, ICU stay, unplanned re-operation, readmission after discharge, the length of hospital stay and cost were analyzed. 2-test, one-way ANOVA, Bonferroni and Turkey's test were used for statistical analysis. (1) There were no significant differences in patient clinical conditions and no sign of deterioration of quality from critical pathway. (2) The length of hospital stay was 13.0 days in control group, 12.2 days in path group I and 10.0 days (p<0.01) in path groupII. (3) The total costs during the hospital stay were reduced. However the cost per day was significantly increased from reduction of hospital stay (358,488won in control, 366,017won in path group I and 413,220won (p<0.01) in path groupII). Critical pathway reduced the length of hospital stay, total hospital costs and resource utilization without harming quality of patient care.

• Wind and Structures
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• v.19 no.5
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• pp.505-522
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• 2014

While effects of the atmospheric boundary layer flow on engineering infrastructure are more or less known, some local transient winds create difficulties for structures, traffic and human activities. Hence, further research is required to fully elucidate flow characteristics of some of those very unique local winds. In this study, important characteristics of observed vertical velocity profiles along the main wind direction for the gusty Bora wind blowing along the eastern Adriatic coast are presented. Commonly used empirical power-law and the logarithmic-law profiles are compared against unique 3-level high-frequency Bora measurements. The experimental data agree well with the power-law and logarithmic-law approximations. An interesting feature observed is a decrease in the power-law exponent and aerodynamic surface roughness length, and an increase in friction velocity with increasing Bora wind velocity. This indicates an urban-like velocity profile for smaller wind velocities and rural-like velocity profile for larger wind velocities, which is due to a stronger increase in absolute velocity at each of the heights observed as compared to the respective velocity gradient (difference in average velocity among two different heights). The trends observed are similar during both the day and night. The thermal stratification is near neutral due to a strong mechanical mixing. The differences in aerodynamic surface roughness length are negligible for different time averaging periods when using the median. For the friction velocity, the arithmetic mean proved to be independent of the time record length, while for the power-law exponent both the arithmetic mean and the median are not influenced by the time averaging period. Another issue is a large difference in aerodynamic surface roughness length when calculating using the arithmetic mean and the median. This indicates that the more robust median is a more suitable parameter to determine the aerodynamic surface roughness length than the arithmetic mean value. Variations in velocity profiles at the same site during different wind periods are interesting because, in the engineering community, it has been commonly accepted that the aerodynamic characteristics at a particular site remain the same during various wind regimes.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.9
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• pp.1455-1462
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• 2020

Objective: The purpose of this study was to investigate whether goose growth and feather characteristics are influenced by their line and feeding surroundings, inclusive of floor materials and types, since there are no reports regarding these factors. Methods: The 240 White Roman geese which were hatched and sex identified came from 3 commercial goose farms. They were randomly distributed to 24 pens depending on a completely random design. The study continued for 13 weeks and included 3 lines of commercial geese and 2 floor types (cement strip floor [CSF] or cement floor [CF]). Results: The day one gosling weight from A farm was lower than other two farms (96 g vs 107 and 115 g; p<0.001). Afterwards, the body weight, back length, keel length, chest girth and main wing feather length among 3 farms showed no significance difference prior to 12 weeks. The CF group showed heavier body weight, shorter back length, longer keel length, shorter chest girth and shorter main wing feather length than the CSF group prior to 12 weeks. The down weight in the CF was heavier than the CSF group (57.1 g vs 41.8 g; p<0.01) prior to 13 weeks. Conclusion: The body weight showed the positive relations for dry feather weight (r = 0.59), down weight (r = 0.69), percent of the down weight of live body weight prior to 13 weeks (r = 0.61).

• PNF and Movement
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• v.16 no.1
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• pp.27-32
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• 2018

Purpose: This study examined changes in gait speed and stride length after an intervention involving simultaneous scapular and pelvic patterns of proprioceptive neuromuscular facilitation in a hemiplegic patient. Methods: A 58-year-old woman with left hemiplegia who had complained of slowness of gait speed and weakness of leg strength took part in an intervention involving scapular postdepression patterns on the affected side and pelvic postdepression patterns on the nonaffected side. The intervention was performed with the patient lying on her left side, in a half kneeling position, and in a standing posture. Rhythmic initiation was used for teaching the movements to the patient and improvement of kinesthesia, and a combination of isotonic was employed for increasing strength and irradiation of the scapula and pelvic movement. The intervention took place for 30 min. It was implemented twice a day, 5 days a week, for 3 weeks. After three repetitions, the average time taken to complete the 10-m walk test (10 MWT), in addition to stride length, was measured to determine gait speed. Results: After the 3-week program, the patient's performance in the 10 MWT improved from 21.7sec to 17.1sec, and her stride length improved from 31.4cm to 38.7cm. Conclusion: The results showed that trunk movement exercise, especially coordinative movements of the scapula and pelvis can improve gait speed and stride length by increasing trunk stability and mobility. A combination of pelvic and scapular patterns can facilitate trunk rotation, thereby improving gait speed and stride length.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.25 no.1
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• pp.63-70
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• 2019

Background: The purpose of this study was to determine the effects of a pelvic compression belt on gait abilities and balance in subacute stroke patients. Methods: Twenty two patients with subacute were recruited and randomly assigned into two group: Two group offered conventional physical therapy and occupational therapy for five day. The group was composed of twelve patients. Participants in the experimental group were given the pelvic compression belt and conventional physical therapy, conventional occupational therapy, although conventional physical therapy and occupational therapy provided in the subjects in the control group. To assess the gait ability, the GAITRITE system was used and the Balance system SD was used to test balance. All measurements were performed before and after intervention. Results: The experimental group shows a significant improvement the cadence, velocity, step length and stride length in gait (p<.05) and show significant increase in the dynamic standing balance (p<.05). However, control group shows a significant improvement the cadence, velocity, step length and stride length in gait (p<.05), but shows no significant differences in dynamic standing balance. Furthermore, there were significant differences gait velocity, dynamic standing balance between two groups (p<.05). Conclusions: The results demonstrated that the elastic pelvic belt application is effective to improve gait velocity, dynamic balance in the subacute stroke patients. Thus, the elastic pelvic belt is seemed to be one of the potential methods to facilitate the active rehabilitation program for hemiplegia patients.