• Journal of Chest Surgery
• /
• v.28 no.11
• /
• pp.1019-1024
• /
• 1995

Clinical analysis were performed on 68 cases of subcutaneous emphysema, those were visited at the emergency center of Chosun university hospital during the period form 1992 to 1994. The following result was obtained. 1 The incidence of subcutaneous emphysema was 0.16%, and male was dominant [M:F=6.9:1 .2 The age distribution of subcutaneous emphysema was from 4 to 77 years old and mean age was 49.6$\pm$17.8 years[$\pm$SD 3 The most presenting symptoms were chest pain[49% , and the proceeding cause was traffic accident[38% . 3 The most associated disease was a ipsilateral pneumothorax[59% . 4 Conservative management is an indication in the majority of cases of subcutaneous emphysema because it is usually a self-limited condition and spontaneous remission usually occurs. We conclude that initial effort must be made to detect the underlying cause of the subcutaneous emphysema in order that appropriate management may be undertaken.

• The Korean Journal of Ecology
• /
• v.14 no.3
• /
• pp.345-360
• /
• 1991

Benthic macroinvertebrates were collecte in the middle reaches of the paenae stream, a tributary of th naktong river in korea, in four seasons from August 1989. To may 1990, during the study period, 125 species, 81 genera and 41 families were collected. Overall, the most dominant species was lepidostoma sp. 1 followed by heptagenia kihada, neoperla quadrata, diamesa sp. 1, ect.. the community was most diverse in autumn, However the number of collectd individuals was highest in winter. Species of chironomids including diamesa sp. 1 and mayflies including paraleptophlebia chocorata were collected exceptionally in a large number in winter. Seasonal occurrence of funtional groups such as collectors, shredders and scrapers was related with the availadlity of food sourses in the stream. The abundance of predators was relatively stable in four seasons with 17% on average. Diversity, tbi and chandler's biotic score(bs) in the paenae strem were 3.75, 14.5, and 100 on average, respectively. Based on biological and chemical indices the paenae stream was clean in the range of xeno- and oligo- saprobity.

• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.1026-1030
• /
• 2007

A linear compressor used in a refrigerator has higher energy efficiency than a reciprocating compressor. But its vibration level is still severe than others. The vibration level of linear compressor at the frequency of 60Hz is dominant since it is the exciting frequency of a motor. Experimental approach to reduce the vibration needs much effort and long period. In this paper, simulation tool to predict the vibration of the shell of the linear compressor was developed. The piston, body and shell are assumed to be rigid, while the loop pipe is flexible. The results by the developed tool showed good agreements with those by experiments.

• Journal of the korean society of oceanography
• /
• v.38 no.3
• /
• pp.111-121
• /
• 2003

The seasonal succession of zooplankton communities in the coastal area off Incheon, Kyeonggi Bay, was investigated with the samples collected at intervals of 10 to 15 days from January 1999 to December 2000. Total abundance of zooplankton communities showed remarkable seasonal variations, ranged from 1,100 to $120,400{\;}indiv./\textrm{m}^3$, and annual mean abundance was $22,000{\;}indiv./\textrm{m}^3$. There were several times of the total abundance during a year, and the timing ofhigh abundances were about the same in 1999 and 2000. During the study period except summer, the abundance of dinoflagellate Noctiluca scintillans and copepod Acartia hongi contributed to the most part of total zooplankton. Whereas, during summer, smaller copepod Oithona davisae and Paracalanus crassirostris were dominant species. Zooplankton communities in the coastal waters off Incheon showed typical characteristics of coastal-estuarine communities, which were dominated by a few species, and abrupt seasonal variations in abundance. We suggest that the seasonal succession and abundance variations of zooplankton communities were caused by the seasonal variations in water temperature and by the seasonally varying phytoplankton biomass in the study area.

• Journal of Korean Society for Atmospheric Environment
• /
• v.10 no.3
• /
• pp.203-208
• /
• 1994

The trend of visibility variation of Seoul during 1980-1993 is analyzed. Annual average visibility has been decreased during the 1980s except 1988 and 1989 but not decreasing during the early 1990s. Also, the number of days with haze during 1983-1993 did not increase. Mixing height is deemed to be a dominant factor determining visibility. During the period, the difference between the average visibility at 6 p.m and 9 a.m decreased with the average visual range at 9 a.m slightly increased. Thus there is possibility that the effect of Photochemcial reactions becomes noticeable. The number of vehicles and the concentration of criteria air pollutants on the trend of visibility variation of Seoul would not be directly related to the variation of visibility.

• Wind and Structures
• /
• v.11 no.2
• /
• pp.137-152
• /
• 2008

This paper discusses engineering aspects of the rear-flank downdraft that was recorded near Lubbock, Texas on 4 June 2002, and produced a gust wind speed nearly equal to the design value (50-year return period) for the region. The general characteristics of the storm, and the decomposition of the time histories into deterministic 'running mean' and random turbulence components are discussed. The fluctuating wind speeds generated by the event can be represented as a dominant low-frequency 'running mean' with superimposed random turbulence of higher frequencies. Spectral and correlation characteristics of the residual turbulence are found to be similar to those of high-frequency turbulence in boundary-layer winds. However, the low-frequency components in the running-mean wind speeds are spatially homogeneous, in contrast to the low-frequency turbulence found in synoptic boundary-layer winds. With respect to transmission line design, this results in significantly higher 'span reduction factors'.

• Journal of Astronomy and Space Sciences
• /
• v.28 no.1
• /
• pp.1-7
• /
• 2011

Characteristics of latitude variations of sunspots in the northern and southern hemispheres are investigated using the daily sunspot area and its latitude during the period from 1874 to 2009. Solar magnetic activity is portrayed in the form of sunspot, regions of concentrated fresh magnetic fields observed on the surface of the Sun. By defining center-of-latitude (COL) as an area-weighted latitude, we find that COL is not monotonically decreasing as commonly assumed. In fact, small humps (or short plateaus) between solar minima can be seen around every solar maxima. We also find that when the northern (southern) hemisphere is magnetically dominant, COL is positive (negative), except the solar cycle 23, which may give a hint that these two phenomena are consistently regulated by one single mechanism. As a result of periodicity analysis, we find that several significant periodicities, such as, of ~5.5, ~11, ~49, and ~167 years.

• Journal of Forest and Environmental Science
• /
• v.32 no.1
• /
• pp.39-54
• /
• 2016

The present study analyzes the diversity and usage of NTFPs and evaluates their importance in the day to day life of the people of rural Meghalaya. People use 172 NTFPs belonging to 139 plant species mainly for food, medicine and fuelwood and to a lesser extent for construction, handicrafts and ornamental purpose. These 139 plants belonged to 117 genera and 70 families with Rosaceae, Poaceae and Fagaceae families as the dominant NTFP yielding families. Fruits from shrubs and trees are most commonly harvested by people. Collection and availability of NTFPs for use as food are more during the summer season, which is also the period with least availability of job. NTFPs for subsistence use are greater in number than those having commercial value. The most commonly harvested plant parts are fruits and leaves. Roots, rhizomes and whole plants are extracted in lesser quantity which is a positive approach from sustainability point of view. NTFPs and other forest products also form a vital part of the rural household's income generation activities.

• Journal of Environmental Science International
• /
• v.7 no.3
• /
• pp.275-280
• /
• 1998

In order to clarify the seasonal composition and abundance of zooplankton commuuty In Macheon Bay. the study was carried out trimonthly during the period from April 1996 to January 1997. 1 species of Cnidana. 1 species of Annelida, 2 Ima of Moiluscs.3 species of Rotifera, 4 species and 4 larspecies was Tintinnopsis beroidea In the spring, Copepodite In the summer, Tintinnopsis beroidea In the autumn and Ceratium risus In the winter. Abundance of zooplankton ranged firom 4.720 to 41,215 Inds./1 It was high In the summer (41,215 inds./l) and low In the spring 14,720 inds./l). Dominant index ranged from 0.133 (in the spring) to 0.551 (in the winter). Species diversity inden ranged from 1.114 (in the winters to 1.996 (in the spring).

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.15 no.4
• /
• pp.333-344
• /
• 1982

Major species of zooplankters were idcentified from the specimens collected from Lake Ok-Jeong for 1 year period and the descriptions are given together with the list of tile species and some drawings. Assuming from the dominant species present in the lake, the Lake Ok-Jeong is considered to be a fairly progressed eutrophlc lake. For a few species, some Questions are presented in taxonomical and biogeographical view points.