• Korean Journal of Ecology and Environment
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• v.49 no.1
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• pp.11-21
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• 2016

Cymbidium kanran Makino is being threatened in its own habitats due illegal collecting and habitat changes by vegetation growth along historical landuse change. In this study, we established habitat restoration model for conservation of C. kanran based on ecological diagnosis. Through exploration to Jeju Island in 2014 and 2015, we identified 27 unknown habitats of C. kanran and in there, abiotic variables and vegetation structure and composition were quantified. Altitudinal distribution of C. kanran was between 200 m~700 m a.s.l. and compared to distribution in 2004, Area of Occupation (AOO) decreased at 82%. Specific habitat affinity was not observed by evenly found in mountain slope and valley and summergreen and evergreen broadleaved forests, but likely more abundant in valley habitats with higher soil and ambient moisture. Total of 96 individual of C. kanran was observed with an average density of $942.6individuals\;ha^{-1}$. The plants showed relatively short leaf length (average=$10.7cm{\pm}1.1cm$) and small number of pseudo bulbs ($1.2{\pm}0.2$). Flowering and fruiting individuals were not observed in field. C. kanran was classified into endangered plant species as CR (Critically Endangered) category by IUCN criteria. Phenotypic plasticity of C. kanran was likely support to sustain in more shaded habitat environment and recent habatat changes to closed canopy and low light availability may exhibit negatively effects to C. kanran's life history. Restoring C. kanran habitat should create open environment as grassland and low woody species density.

• The Journal of the Korean Society for Microbiology
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• v.3 no.1
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• pp.35-41
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• 1968

An outbreak of typhoid fever in Samchunpo city was surveyed and the results were summarized as follows: 1. 638 of clinical cases were detected in 17 Dongs(districts) of the city of Samchunpo,(54,064), during the epidemic period from 1st September to the end of November, 1967. 2. The morbidity rate was 1,189 per 100,000 population;(1,300 female, and 1,060 male). 3. The highest peak was reached in the third week of September and a second peak appeared at the end of September 1967. 4. The mode of infection was suspected strongly as a water-borne and the source of infection as an old public well called Gal-Dae-Saim, since the causative agent was found in close public latrine and the contaminated sewage ditch witch was connected with the well. 5. All patients and carriers were treated at their home under the supervision of local medical authorities. 6. The Gal-Dae-Saim was closed immediately on 7th October, 1967 by the order of the mayor. 7. At the end of November, 1967 when the outbreak in Samchunpo was almost ended, another small epidemic occurred in Koseong county which bordered the eastern outskirt of the city. 8. During the survey, a strain of Shigella flexneri was isolated from the sewage located three meters from Gal-Dae-Saim and also from one case. 9. It was reported by the local health center in May, 1968, that no carrier had been detected in the survey made among the persons who had had typhoid fever in 1967. Also thereafter no cases of typhoid fever were reported through October, 1968.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.272-277
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• 1998

Filtering rates of two farming ascidians Styela clava and S. plicata, and of a farming mussel Mytilus edulis were experimentally investigated with reference to effects of water temperature and size. Absorptiometric determinations of filtering rates were carried out in a closed system with experimental animals being decreased indicate dyes neutral red. Optical density (OD) of 440 nm in path length 22 mm cell used as the indication of food particles absorption was appeared directly in proportion with the concentration of neutral red dyes. The filtering rate F is calculated by Kim's equation $F\;=\;V(1-e^{-z})$, where V is the water volume ($\ell$) in the experimental jar, and Z is the decreasing coefficient of OD as meaning of instantaneous removal speed as In $C_t\;=\;In\;C_{o}-Z{\cdot}t$, in this formula $C_t$ is OD at the time t. Filtering rate of S. clava increased as exponential function with increasing temperature while not over critical limit, and the critical temperature for filtering rate was assumed to be between $28^{\circ}C$ and $29^{\circ}C$. In case of S. plicata, the critical temperature was to be below $13^{\circ}C$, and through the temperature range $15\~25^{\circ}C$ appeared a little difference in level even though with significant. M. edulis was not appear any significant effects by water temperature less than $29^{\circ}C$. The model formula derived from the results is as below, where F is filtering rate (${\ell}/hr/animal$), T is water temperature ($^{\circ}C$), and DW is dry meat weight (g) of experimental animal. $$S.\;Clava;\;F\;=\;e xp\;(0.119\;T-4.540)\;(DW)^{0.6745},\;T<29^{\circ}C$$) $$S.\;plicata;\;F\;=\;e xp\;(A_t)\;(DW)^{0.5675},\;(13^{\circ}C $$[A_t =-8.56+0.6805\;T-0.0153\;T^2]$$ $$M.\;edulis;\;F\;=\;0.3844\;(DW)^{0.4952},\;<29^{\circ}C$$)

• Korean Journal of Occupational Health Nursing
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• v.4
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• pp.58-83
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• 1995

The small scale industries which have less than 30 employees occupy 86.5% of total number of industries in Korea. And though they have higher accident rate and lower environmental condition than big industries, it has been not mandatory to appointing health care manager at factory. So, from 1993, government subsidizes to the health care management of small industries. The purpose of this study is to identify the real feature of health care status in small industries, and to evaluate the level of health care management, before and after the subsidiary program. 65 small plating industries which have been managed by the same health care management support institution in 1993 were selected for study. Of the 65 industries, 3 which have not taken both environmental evaluation and health screening in 1994, and 9 which have closed were excluded from study sample. And the remaining 53 were analyzed by using the results of environmental evaluation and health screening, reported to the Ministry of Labor, before and after the subsidiary program, the analysis was done by the comparison of the two year paired data of the same industry. Over-permissible-limit rate, health screening implementation rate, above grade C rate were calculated and compared. The status of health care management ; 1. Of the sample industries, 96.9% provide protective equipment and 80.0% set up ventilating system. Protective gloves (89.2%) and protective clothing (80.0%) are widely provided, but ear plugs (4.6%) are rarely provided. 21.5% of the protective equipment are well put on, and 40.4% of the ventilating systems function well. 2. In 1993, 35 industries, 53.8% of the sample, checked working environment twice. Over-permissible-limit rates of heavy metal (12.2%), suspended particle (11.1%), noise (5.5%) were high. To put on protective equipment and to set up local ventilating system were pointed out by the examiners. 3. General health screening was done at 63.1% of the sample industries and 35.3% of total workers were examined. Specific health screening was done at 93.8% of the sample industries and 75.4% of workers were examined. 15.5% of workers was provided to be above grade C and to have digestive system disease (43.3%), circulatory disease (18.9%), and hematopoietic disease (14.2%), etc. 4. In 1993, the subsidiary program of health care management was provided in forms of health education, health counseling, and rounding check of working field. And 61.5%, 83.0%, 55.4% of sample industries respectively received it. The average visit per industry was 1.8. Comparisons of the level of occupational health before and after the subsidiary program ; 1. Over-permissible-limit rates of hazardous factors of 1993 and that of 1994 were compared. The rates of suspended particle, noise, organic solvent of 1994 (37.5%, 13.4%, 24.2% respectively) were higher than that of 1993 (25.0%, 6.0%, 6.3% respectively). In the case of acid, there was no difference between the rate of 1993 and that of 1994. Only the rate of heavy metal decreased from 12.9% in 1993 to 3.0% in 1994. 2. General health screening was done at 38.7% of the sample industries in 1993 and at 44.6% in 1994. But the implementation rate of specific health screening decreased from 72.4% in 1993 to 64.6% in 1994. 3. The implementation rate of specific health screening was analyzed by some health factors. The rate of suspended particle increased from 61.8% in 1993 to 91.2% in 1994. But the rates of the others-noise, organic solvent, heavy metal, specific chemical substances-decreased. 4. Above grade C rate in health screening increased from 27.8% in 1993 to 35.5% in 1994. But that of endocrine disorders and pulmonary disease decreased.

• Korean Journal of Ichthyology
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• v.12 no.2
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• pp.137-145
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• 2000

The embryonic and larval development of Chelon lauvergnii (Eydoux & Souleyet) was surveyed by incubating artificially inseminated eggs with parent fishes obtained at Kang-wha island in the mid-western coastal area of Korea on June, 1997. The fertilized eggs were transparent, spherical in shape, measuring 0.95~1.08 mm in diameter, having a large oil globule, and their perivitelline space narrow, and began to hatch at 40 hrs. in water temperature $22{\pm}1^{\circ}C$. The newly hatched larvae were 2.35~2.68 mm in total length with 23 myomeres, anus opened, mouth closed, preanal length 58.7~61.6% of total length, oil globule located in posterior end of yolk sac. Melanophores, branch in shape, were distributed mainly along the ventro-lateral region of trunk part and a few on the anterior end of caudal part and surface of oil globule. The larvae measuring 3.08~3.36 mm in total length absorbed yolk material completely in 3 days after hatching, in which air bladder began to appear and mouth opened. In 8 days after hatching, the larva was measured 5.09 mm in total length, its posterior end of notochord began to flex upward and the caudal fin rays differentiated as 7, finfold of the second dorsal and anal fins appeared. In this time, melanophores, branch in shape, were concentrated in the anterior half region of the caudal part and a few also distributed on the top of head, snout region, ventral margin of lower jaw and isthmus region. In 12 days after hatching, the larva measuring 8.48 mm in total length completed all the fins (D. IV-9; P1. 16; P2. I, 5; A. II, 9) and reached to the juvenile stage. Melanophores, in this time, were distributed on the mid-lateral region of the caudal part in enlargment than before and a few also found in the dorso-lateral region of the trunk part, and in the cheek region.

• Journal of the Korean association of regional geographers
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• v.6 no.2
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• pp.83-96
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• 2000

Erosional basins formed in middle and upper reaches of Korean great rivers have been main life space of local small and middle cities, but previous studies on erosional basins are widely apart from residents' life and are in shortage with the endeavor to elucidate the man and environment relationship. This paper analyzes the factors and the modes of land-use changes of hills in the erosional basin. In this paper four erosional basins with different geological conditions are selected to elucidate the effect of geological factor(Geochang: granite, Chogye: metamorphic rock, Angye: gravelly sedimentary rock, Maseong: limestone). And the distribution of land use on the transverse and longitudinal cross-section map of the hill is described. The landscape of erosional basin is consisted of surrounding mountains, hills, dissected valleys, and incoming river's floodplain. Dissected valleys and incoming river's floodplain were reclaimed early as paddy field and hills have been used as woodland up to recently. Residents have a new appreciation of hills as a productive hill out of a traditional holy space[mountain] by influence of capitalistic thought that 'natural environment is a sort of productive resource'. Population increase is the another pressure of hill reclamation. The modes of landscape changes due to natural conditions are as follow: (1) In Geochang basin with dense tectolineament spacing, the gentle part of hill is used as field, orchard and agricultural-industrial complex site and the steep part is as woodland. (2) Hills in Angye basin with sparse tectolineament spacing are relatively flat because of maintaining a part of original denudational surface, and are used as orchids, field, paddy fields and agricultural-industrial complex site. The dissection valleys between hills are gentle concave and are used as paddy fields. (3) Hills in Maseong basin are wide and flat, and are used as fields, orchards, and agricultural-industrial complex site. (4) Because hills in Chogye basin, a closed type, are weared by affluents and are narrow and short. Hills are used as woodland and wide dissected valleys are reclaimed as paddy fields.

• Journal of Conservation Science
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• v.25 no.1
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• pp.1-16
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• 2009

Jeollabuk-do is bounded by the sea, and Mahan Baekje culture have been established around a wide plain. Also, in southeastern, it was closed by Gaya kingdom where iron culture was prosperous at that time, a variety of the handles of swords with round pommel is excavated at present. The handles of swords with round pommel is the best amount of excavated objects among the swords with round pommel and producted object for the time. It supposes them to become the foundation of making the decorated swords with round pommel. But, the handles of swords with round pommel that don't have a pattern in handle is indifferent to study because the production method is simple in spite of that the value of archaeological data is sufficient. Therefore, in this study, it examined changed production techniques with the change of times concerning the handles of swords with round pommel of Mahan Baekje Gaya period(before 6C) excavated from Jeollabukdo through using X-rays in order to clarify a variety of production techniques of the handles of swords with round pommel correctly in accordance with a period of production and excavated place. As a result, identified production techniques using X-rays of the handles of swords with round pommel excavated around remains of Mahan Baekje Gaya period shows that production progress improved in order of all-in-one shape, hammer welding shape of the handle of round pommel, and two in body formation in accordance with age. Especially, in two in body shape, it products the handle of round pommel separately, after that it welds the handle of swords and then links the sword blade like a riveting or bottleneck and so on. Despite of improved hammer welding technique, the reason why it didn't utilize is it regards as inlay or gilt will be damaged. And it is judged by using riveting or bottleneck. Also, it appears to techniques of metal craft such as decoration of the handle, decoration of point of sword, inlay, and silver-plating in the period of appearing two in body shape. As clarifying correctly, it provides fundamental database of scientific research about a study of production techniques of handle of swords with round pommel.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.322-332
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• 2013

This study was conducted to understand the control mechanism of Sika deer (Cervus nippon taiouanus) populations which are adapted to the natural forest areas and the semi-natural forest areas of Korea. We monitored and analyzed the behaviour patterns and habitat characteristics of Sika deers. After we released 12 Sika deers (male 3, female 9) each at the two study areas in and around Seoul under the approval of Korean government, we monitored them through our survey researchers' naked eyes from May 2011 to January 2012. We discriminated their habitat patterns to 4 major places - eating food place, drinking water place, daytime rest place, and nighttime rest place. Our results showed that Sika deer preferred the open grassland habitats for feeding and resting in daytime but the closed bushland for their protection and sleep. We also found the recommended sex ratio of adult male to female in a herd was 1 : 4~9 for breeding and they had few cubs in a herd. The average amount of food for 1 adult deer was 391.62 kg of fresh grasses and 286.90 kg of hay per year. Our results suggest that the amount of drinking water required for a deer when grazed on grasses during spring and summer seasons is 256.8 L and when a deer feeds on dry food during autumn and winter seasons, 209.8 L of water is required. From these results, we observe that the amount of drinking water was affected substantially by the moisture content of their food. This observational study must be very valuable for land managers to judge the number of deers that should be released in natural areas without high risk and to ascertain the sex ratio of large mammals including Sika deer. Therefore, we conclude that this population control mechanism study consists of efficient basic data and their values must be very effective for various purposes.

• Korean Journal of Heritage: History & Science
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• v.53 no.2
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• pp.254-269
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• 2020

The purpose of this study is to propose guidance for wall renewal that is appropriate for an ancient city wall through application of advanced research and theories in wall design. It is a streetscape improvement project which forms part of the "Ancient City Image Finding Project". Study methods consist of advanced research classification, wall design theory contemplation, and analysis of the significance of designated ancient city areas and the "Ancient City Image Finding Project" status. Based on these methods, case study candidates were selected, case status and problems were identified, and improvement proposals were analyzed by comparing various features. Advanced wall research was classified into six categories including analysis of wall characteristics; wall design principle applications; wall structure, color, shape, and application; modern reinterpretation; palace walls; and house, temple, and village walls. The wall is an element of the streetscape improvement component of the "Ancient City Image Finding Project", with the characteristic of providing preceding experience in visual and cognitive awareness than interior structure. Case candidates for ancient city wall improvement are based on the composition distribution of the special conservation district in each ancient city as well as the conservation promotion district. Ultimately, the surrounding village of Gongju-si Geumseong-Dong Songsanri-gil, adjacent to the Royal Tomb of King Muryeong, was selected as the candidate. The "Ancient City Image Finding Project" of the surrounding village of Gongju-si Geumseong-Dong Songsanri-gil began with new Hanok construction. However, wall maintenance did not begin concurrently with that new Hanok construction. Support and maintenance took place afterwards as an exterior maintenance project for roadside structures. If the Hanok and wall were evaluated and constructed at the same time, the wall would have been built in unison with the size and design of the Hanok. The layout of the main building and wall of the Hanok is deemed to be a structure that is closed tightly because of its spatial proximity and tall height. Songsan-ri-gil's wall design should create a calm, subtle, and peaceful atmosphere with shapes, colors, and materials that express ancient city characteristics, but it is in an awkward position due to its sharpness and narrowness. The cause of the problem at Gongju-si Geumseong-dong Songsanri-gil, the case candidate, is that it is lacking significantly in terms of the aesthetic factors that traditional walls should possess. First, aesthetic consciousness seems to have disappeared during the selection and application process of the wall's natural materials. Second, the level of completion in design and harmony is absent. Maintenance guidance after analyzing the cause of problems in ancient city wall maintenance at Gongju-si Geumseong-dong Songsanri-gil, the subject area of research, is as follows: First, the Hanok design and layout of the wall and main gate should be reviewed simultaneously. Second, the one-sided use of natural stone wall in the Hanok wall design should be reexamined. Third, a permanent system to coordinate the opinions of citizens and experts during the planning and design phases should be employed. Fourth and finally, the Hanok's individuality shall be collectivized and its value as a cultural asset representing the identity of the community shall be increased.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.392-400
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• 2003

We used an oxygen microelectrode to measure the vertical profiles of oxygen concentration in sediments located near point sources of organic matter. The measurements were carried out between 13th and 17th May, 2003, in semi-closed bay and coastal sediments in the central part of the South Sea. The measured oxygen penetration depths were extremely shallow and ranged from 1.30 to 3.80 mm. This suggested that the oxidation and reduction reactions in the early diagenesis should be studied at the mm depth scale. In order to estimate the oxygen consumption rate, we applied the one-dimension diffusion-reaction model to vertical profiles of oxygen near the sediment/water interface. Oxygen consumption rates were estimated to be between 10.8 and 27.6 mmol O$_2$ m$\^$-2/ day$\^$-1/(average: 19.1 mmol O$_2$ m$\^$-2/ day$\^$-1/). These rates showed a positive correlation with the organic carbon of the sediments. The corresponding benthic organic carbon oxidation rates calculated using an modified Redfield ratio (170/110) at the sediment/water interface were in the range of 89.5-228.1 mg C m$\^$-2/ day$\^$-1/(average: 158.0 mg C m$\^$-2/ day$\^$-1/). We suggest that these results are maximum values at the presents situation in the bay because the sampling sites were located near point sources of organic materials. This study will need to be carried out at many coastal sites and throughout the seasons to allow an understanding of the mechanisms of eutrophication e.g. the spatial distribution of oxygen consumption within the oxic zone and hypoxic conditions in the coastal sea.