• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.694-699
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• 2008

Considering the severe regulation associated with sludge treatment such as direct landfill and ocean dumping, there is no doubt in that an advanced study for the proper treatment of sludge is urgently needed in near feature. As one of viable method for sludge treatment, fry-drying of sludge by waste oil has been investigated in this study. The fundamental mechanism of this drying method lies in the phenomenon of rapid moisture escape in the sludge pore toward oil media. This is caused by the severe pressure gradient formed by the rapid oil heating between sludge and oil. As part of research effort of fry-drying using waste oil, a series of basic study has been made experimentally to obtain typical drying curves as function of important parameters such as drying temperature, drying time, oil type and geometrical shape of sludge formed. Based on this study, a number of useful conclusion can be drawn as following. The fry-drying method by oil immersion was found quite effective in the removal efficiency of sludge moisture, in general, the moisture content decreases significantly after 10 minutes and the whole moisture content was less than 5% after 14 minutes regardless of the drying temperature. The increase of oil temperature up to 140$^{\circ}C$ favors significantly for the removal of moisture but there was no visible difference above 140$^{\circ}C$. As expected, the decrease of diameter in sludge was efficient in drying due to the increased surface area per unit volume. Further, the effect of oil property by the change of oil type was noted. To be specific, for the case of engine oil the efficiency was found to be remarkably delayed in moisture evaporation compared with that of vegetable oil due to the increased viscosity of engine oil. It produced a result of increasing the evaporation of moisture largely relatively high in the drying temperature over 140$^{\circ}C$ compared with the drying temperature 120$^{\circ}C$ drying temperature as the drying time passed. Accordingly, the drying temperature is considered desirable as keeping over 140$^{\circ}C$ regardless of a sort of used oil.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.11
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• pp.835-860
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• 2013

Recently, the consumption of nanomaterials has been significantly increased in both industrial and commercial sectors, as a result of steady advancement in the nano-technologies. This ubiquitous use of nanomaterials has brought up the concern that their exposure to environments may cause detrimental effects on human health as well as natural ecosystems, and it is required to characterize their behavior in various environmental media and to evaluate their ecotoxicity. For the sake of accomplishing those assessments, the development of methods to effectively separate them from diverse media and to quantify their properties should be requisitely accompanied. Among a number of separation techniques developed so far, this study focuses on Field-Flow Fractionation (FFF) because of its strengths, such as relatively less disturbance of samples and simple pretreatment, and we review overseas and domestic literatures on the separation of nanomaterials using the FFF technique. In particular, researches with Flow Field-Flow Fractionation (FlFFF) are highlighted due to its most frequent application among FFF techniques. The basic principle of the FlFFF is briefly introduced and the studies conducted so far are classified and scrutinized based on the sort of target nanomaterials for the purpose of furnishing practical data and information for the researchers struggling in this field. The literature review suggests that the operational conditions, such as pretreatment, selection of membrane and carrier solution, and rate (velocity) of each flow, should be optimized in order to effectively separate them from various matrices using the FFF technique. Moreover, it seems to be a prerequisite to couple or hyphenate with several detectors and analyzers for quantification of their properties after their separation using the FFF. However, its application has been restricted regarding the types of target nanomaterials and environmental media. Furthermore, domestic literature data on both separation and characterization of nanomaterials are extremely limited. Taking into account the overwhelmingly increasing consumption of nanomaterials, the efforts for the area seem to be greatly urgent.

• Clinical and Experimental Pediatrics
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• v.49 no.11
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• pp.1194-1201
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• 2006

Purpose : The comatose mentality can be catastrophic, especially if the condition is severe or the duration is prolonged. Therefore, delayed diagnosis can result in a poor outcome or death. The best radiologic modality to differentiate from cerebral lesions in patients suffering from cerebral diseases is magnetic resonance imaging (MRI) rather than computed tomography (CT). Special apparatuses with metal materials such as ventilators, and cardiac pacemakers belonging to patients cannot be located in the magnetic field. We aimed to exhibit the possibility of examining MRI, maintaining ventilation at a relative long distance by means of modified $Ambu^{(R)}$. Methods : Self-inflating bags as a sort of a manual ventilator, connected with relatively long extension tubes instead of mechanical ventilators, were adopted to obtain MRI. PVC (polyvinyl chloride) extension tubes had different lengths and diameters. Lengths were 1, 2, and 3 cm and diameters were 15, and 25 mm. The work of breathing and expiratory changes of expiratory tidal volume (TVe), minute volume of expiration (MVe), peak inspiratory pressure (PIP) were measured by use of the mechanical ventilator, $Servoi^{(R)}$, as the alteration of TVi (inspiratory tidal volume), extension tube lengths and diameters with other values fixed. Results : Measured TVe and MVe by ventilator were the same values with control at every TVi, regardless of extension tube lengths and diameters, but PIP were increased with the rise of TVi, tube lengths, with decline of tube diameters, these were statistically significant. Conclusion : MRI examination can be carried out with a self-inflating bag connected with an extension tube at a long distance in patients who need artificial ventilation.

• The Korean Journal of Pharmacology
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• v.1 no.1 s.1
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• pp.17-36
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• 1965

Besides it's all important analgesic action, morphine has, among others, hyperglycemic effect, though not important clinically, which is believed to be resulted from augmented glycogenolysis in the liver and muscles due to the increased liberation of epinephrine from the adrenal medulla upon the stimulation of the posterior part of hypothalamus. It is known that adrenergic blocking agents are acting inhibitory to this sort of hyperglycemia. Much, however, should as yet be studied for the drugs which affect central nervous system and release of endogenous catecholamine as far as their effects on hyperglycemia are concerned. Much is still not known about the effect of ginseng, which has been highly regarded in the Herb Medicine, as far as it's influence on the blood sugar is concerned. Author investigated the effects of chlorpromazine, reserpine and ginseng on epinephrine induced, and morphine-induced hyperglycemiae. Animals used in this experiment were healthy albino rabbits weighing approximately 2.0 kg of body weight and were all fasted for 24 hours, before the experiment undertaken. Blood sugar determination was carried out by Nelson-Somogy method. Results obtained are summarized as follows; 1. The groups of rabbits administered intravenously with epinephrine 0.02 mg/kg, and 0.05 mg/kg, showed marked and transient hyperglycemia within 15 minutes after injection. The maximal rate of elevation in blood sugar to the control level, were 28% and 57% respectively. The blood sugar returned to the control level within 3 hours. Thus, the hyperglycemic responses were paralleled with epinephrine doses. 2. The hyperglycemic responses by morphine were different according to the doses. The groups of rabbits in which 4 mg/kg of morphine was administered, did not show any hyperglycemic effect, but, in which 10 mg/kg of morphine administered, showed severe hyperglycemic effect, resulting in the maximal level within 2 hours after injection. The maximal rate of increasing in blood sugar ,level was 88%. Compared .with epinephrine-injected groups, morphjne-injected groups showed more persistent hyperglycemic effect, but returned to control blood sugar .level in 6 hours after injection. 3. The intravenous injection of chlorpromazine 2 mg/kg and 8 mg/kg evoked a slight, and persistent hyperglycemia. The maximal rate of increasing in blood sugar level were 15% and 23% respectively. These hyperglycemia gradually returned to the normal level in 5 or 6 hours after injection. Thus, the intensity of response was paralleled with the dose of chlorpromazine. 4. The intravenous injection of reserpine 0.2 mg/kg and 0.5mg/kg, showed the most persistent but steady elevation of blood sugar level in this experiments, resulting in the maximal level in 5 hours after injection. The maximal rate of increasing of blood sugar level were 18% and 39% respectively. 5. The blood sugar level from 24 hours to 30 hours after intraperitoneal administration of reserpine 1.0mg/kg, did not show statistically significant difference, compared with control groups. 6. The oral administration of ginseng extract 15 ml/kg did not. show any :change in blood sugar level. 7. The intravenous administration of epinephrine 0.05 mg/kg or morphine 4 mg/kg to the group pretreated with ginseng extract 15 ml/kg $20{\sim}30$ minutes before the experiment, evoked more marked hyperglycemic effect than the non-pretreated group. 8. The intravenous administration of epinephrine 0.02 mg/kg, morphine 4 mg/kg, or morphine 10 mg/kg to the groups pretreated with reserpine 0.2 mg/kg or 0.5 mg/kg $20{\sim}30$ minutes before experiment, produced more marked and persistent hyperglycemic effects than the groups injected with single epinephrine or morphine injection. 9. When epinephrine 0.05 mg/kg or morphine 10 mg/kg administered intravenously to the groups pretreated with the intraperitoneal administration of reserpine 1 mg/kg 24 hours before experiment morphine-induced hyperglycemia was inbibited, but epinephrine-induced hyperglycemia was augmented. 10. When epinephrine 0.05mg/kg or morphine 10 mg/kg administered intravenously to the groups pretreated with chlorpromazine, 2 mg/kg, 4 mg/kg, and 8 mg/kg $20{\sim}30$ minutes before the experiment, morphine-induced hyperglycemia was inbibited, but epinephrine-induced hyperglycemia was more persistent.

• Journal of Soil and Groundwater Environment
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• v.7 no.2
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• pp.63-71
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• 2002

The authors selected the modified soil method, and then performed the geotechnical and environmental laboratory test, and evaluated whether the modified soil liner could be accepted as a barrier layer in landfill. Unlike the results of the natural soil(CL), those of the hydraulic conductivity test of stabilized soil met the standard value. According to these results, the optimal mixing ratio of a mixture(cement : bentonite : stabilizing agent) was 90 : 60 : 1 with mass ratio(kg) for 1㎥ with soil, and it was possible to use poor quality bentonite. B\circled2 because of a little difference from results with high quality bentonite. B\circled1. The Cation Exchange Capacity(CEC) of the modified soil was increased about 1.5 times compared with the natural soil; however. the change of CEC with a sort of additives was not detected. In order to observe the change of the chemical components and crystal structures, the natural and the modified soils with the sorts of additives were measured by the XRF(X-Ray Flourescence Spectrometer) and SEM, but there was no significant change. The artificial leachate with the heavy meals ($Pb^{2+}$ , $Cu^{2+}$, $Cd^{2+}$ Zn$^{2+}$ 100mg/L) was passed through the natural soil and modified soils in columns. In the natural soil, Cd$^{2+}$ and $Zn^{2+}$ were identified, simultaneously the pH of outflow was lower, and then came to the breakthrough point. The removal efficiency of the natural soil was showed in order of following : $Pb^{2+}$ ≒$Cu^{2+}$ > $Zn^{2+}$ > $Cd^{2+}$ On the other hand, modified soils were not showed the breakthrough condition like the result of the natural soil. The modified soil with the lower quality bentonite, B\circled2(column3) was more stable with respect to chemical attack than that with the higher bentonite, B\circled1(column2) because the change range of outflow pH in columns was less than that of outflow pH in column2. In addition, the case of adding the stabilizing agent(column4) was markedly showed the phenomena.ena.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.261-270
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• 1992

Many herbicides that are applied at the soil before weed emergence inhibit plant growth soon after weed germination occurs. Plant growth has been known as an irreversible increase in size as a result of the processes of cell divison and cell enlargement. Herbicides can influence primary growth in which most new plant tissues emerges from meristmatic region by affecting either or both of these processes. Herbicides which have sites of action during interphase($G_1$, S, $G_2$) of cell cycle and cause a subsequent reduction in the observed frequency of mitotic figures can be classified as an inhibitor of mitotic entry. Those herbicides that affect the mitotic sequence(mitosis) by influencing the development of the spindle apparatus or by influencing new cell plate formation should be classified as causing disruption of the mitotic sequence. Sulfonylureas, imidazolinones, chloroacetamides and some others inhibit plant growth by inhibiting the entry of cell into mitosis. The carbamate herbicides asulam, carbetamide, chlorpropham and propham etc. reported to disrupt the mitotic sequence, especially affecting on spindle function, and the dinitroaniline herbicides trifluralin, nitralin, pendimethalin, dinitramine and oryzalin etc. reported to disrupt the mitotic sequence, particularly causing disappearence of microtubles from treated cells due to inhibition of polymerization process. An inhibition of cell enlargement can be made by membrane demage, metabolic changes within cells, or changes in processes necessary for cell yielding. Several herbicides such as diallate, triallate, alachlor, metolachlor and EPTC etc. reported to inhibit cell enlargement, while 2, 4-D has been known to disrupt cell enlargement. One potential danger inherent in the use of soil acting herbicides is that build-up of residues could occur from year to year. In practice, the sort of build-up that would be disastrous is unikely to occur for substances applied at the correct soil concentration. Crop injury caused by soil applied herbicides can be minimized by (1) following the guidance of safe use of herbicides, particularly correct dose at correct time in right crop, (2) by use of safeners which protect crops against injury without protecting any weed ; interactions between herbicides and safeners(antagonists) at target sites do occur probably from the following mechanisms (1) competition for binding site, (2) circumvention of the target site, and (3) compensation of target site, and another mechanism of safener action can be explained by enhancement of glutathione and glutathione related enzyme activity as shown in the protection of rice from pretilachlor injury by safener fenclorim, (3) development of herbicide resistant crops ; development of herbicide-resistant weed biotypes can be explained by either gene pool theory or selection theory which are two most accepted explanations, and on this basis it is likely to develop herbicide-resistant crops of commercial use. Carry-over problems do occur following repeated use of the same herbicide in an extended period of monocropping, and by errors in initial application which lead to accidental and irregular overdosing, and by climatic influence on rates of loss. These problems are usually related to the marked sensitivity of the particular crops to the specific herbicide residues, e.g. wheat/pronamide, barley/napropamid, sugarbeet/ chlorsulfuron, quinclorac/tomato. Relatively-short-residual product, succeeding culture of insensitive crop to specific herbicide, and greater reliance on postemergence herbicide treatments should be alternatives for farmer practices to prevent these problems.

• Journal of agricultural medicine and community health
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• v.12 no.1
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• pp.36-53
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• 1987

It is utmostly important to establish the efficient fitable way of peoples' active participation in primary health care especially in the areas where the public or governmental service input for the basic health care is insufficient like as in rural areas of Korea. In light of above reason, this study focused mainly on the evaluation of roles and activities of village health workers (VHWs) who were selected from grass- root level of village people in order to derive further motivation for active participation. This is believed to be a sort of feedback mechanisms. Actually, the authors collected the activity reports of VHWs who had been devoting themselves in the primary health care services of Jeomdong Area, of Yeoju Gun one of Korea University Community Health Action Programmes and survey record on the VHWs activity from correspondent people. 1 hose data were analyzed through computer programmed package. The activities performed by VHWs were limited to the performance in 1985 for conveniance. The summarized results were as follows; 1) General characteristics of VHWs. Among a total of 28 VHWs in the area, about 39.3g of them have been replaced up to the date since the implementation in 1983, because of moving out, occupational employment and of others. The age of majority (75.0%) lied between the range of 30-50, and educational background of 67.9% belonged to category of primary school graduation, about 50% of them experienced to be or were also entiled "chief of women club" of corresponding villages. 2) Work-load of VHWs. Each VHW was assigned for tasks of health care for average 55 households of 248 persons. They shared approximately 6 days a month for the activity in average and it covered 17 cases of basic health care in a month. A half of the VHWs performed home visits irregularly without solidified schedule. 3) Work performance analysis. Informations collected through VHWs were compared with data from official vital registration at local administration center "Myon Office" in 1985. VHWs collected 100.8 of new born, 116.2 of death, 58.3 of move in and 74.8 of move out in comparison with 100.0 of official registration each. Pregnant women of 79.8% of mothers among the total pregnancy of 94 which were confirmed as normally delivered or aborted cases by all means afterwards had been detected by VHWs as being pregnant and all of them received some of antenatal cares by VHWs. All(100%) of delivered women were detected by VHWs through home visits and they were cared postnatally. Whereas, according to the records of birth registration, the places of delivery were clinic in 33.7%, and mother's home in 66.3%, VHWs reported them to be clinic in 48.9%, midwifery in 20.2%. It was cleared that most of misinformation was caused by uncautious filling of birth registration at notification. Among the total of 717 eligible women under age 44 years, family planning status of 92.6% was reported by VHWs confirming practice of control to be 70.8% of reported fertile women. 4) Attitude of VHW on the roles and functions. Although 92.0% of VHWs expressed VHWs to be worthwhile, only 52.0% of them had dignity and satisfaction in their activity and 44.0% of them had passive attitude of working saying they followed direction regardlessly. Concerning difficulties in performance as a VHW, 60.7% of them pointed out lacking of medical and health related knowledge by themselves. Still, 64.0% of them thought visiting unfamilier house to be awful and 40.0% complained forms of activity to be difficult and hard. It was also revealed that 56.6% confessed lack of interest on community health service itself. Most of VHWs needed more educational training especially on clinical fields such as cares of gynecological diseases, hypertension, diabetes, and other chronic diseaes of the aged. Regular on-the-job basic trainings were said to be needed twice a year.

• Korean journal of communication and information
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• v.43
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• pp.173-208
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• 2008

This study analyses the business performance according to the business diversification of Korean mass media enterprises from year 2003 to 2006. The conclusions drawn which could be divided into five main parts are the followings: First, newspaper companies pursue unrelated diversification in various industrial areas, in order to gain maximum profit while broadcasting companies exert themselves to provide better service by diversifying the major contents. Second, overall the interviewed companies display a constant decline in profit gained from their major business area thus establishing strategies to broaden their focus on diversification of any sort. Third, the researcher completed group analysis in regard of diversification measure resulting in division of three groups. The group which had the most immense diversification range gained the highest ROE, the lowest ROE volatility, and lesser probability of risk taking. The analysis adresses the companies broadening their business areas by researching and focusing on diversification are relatively stable in terms of the profit they gain. Fourth, the middle level group in terms of sales scale, debts, enterprise history, major share rate and high ROE group carry out diversification progressively. The sales scale affects positively to diversification, while the major share rate affects negatively to diversification. Fifth, in accordance to the research, diversification overall contributes to obtainance of successful outcome. Since there was not an immense amount of studies to be referred in the media area, the researcher interviewed and did panel discussion with numerous strategists and managers who are in charge of diversification of media companies. However, collection of only 4 years of data limits the research to be considered to be a generalized study, and does not reflect time gap between business diversification and business performance. Development is required in future studies to be established regarding the media companies' specificity different to other industries, classified the media companies into media types, and consider the time gap in the diversification activities and business performance.

• Journal of the Korean Geographical Society
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• v.29 no.1
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• pp.46-64
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• 1994

Among every civilized people salt has been recognized as an essential foodstuff to the human society without which even man's survivor is unthinkable. The cultural-anthropological meaning of salt is estimated highly as well, and in geographical perspective salt itself symbolize regional interrelationship. Playing a decisive role in freeing innermost settlement from isolation, salt aiso made a contribution to expanding human habitats. This study tries to reconstruct historica geography of 18th and 19th century surrounding traditional salt-roasting (chayeom). The Joolpo Inlet area which is located on the mid-western coast in Honem Region is selected for study area. Established on the basis of optimum physical geographical conditions such as topography, climate and vegetation, salt-making of Joolpo Inlet area was run dynamically with the sudden turn of events in the 18-19th century which was chacterized as an age of transition from medieval society to modern one. In this paper the writer attempts to clarify mainly following three points: physical conditions and socio-economic background leading to the initiation and later development of roasting of salt in Joolpo Bay; distribution of saltworks; methods of saltmaking. Main points drawn from these analyses can be summarized as follows: of iron pan and cow-drawn tools rendered labour-saving and output growth. 1, Saltworks of Joolpo Inlet area in the 18-19th century were distributed evenly over Kobu, Puan, Mujang and Heungduck counties among which Kobu's was located in Puanmyon - a sort of exclave. All saltworks belonging to above four counties were clasified as most lucrative ones in Honam Region on government archives. In particular, Gumdang saltwork which belongs to Mujang county is noteworthy in that it was first introduced by one Paekje priest in 6th century and therefore it provides a clue to examine the history of salt-roasting of Joolpo Inlet area. In light of the fact that temple or monastery economy, regardless of East and West, has been closely connected with traditional industry, the case of Gumdang is not unusual. 2. The process of saltmaking follows this order: harrowing of salt field exposed to solar heat; construction of saltern mound with saline earth; acquiring of brine by leaching saline earth; roasting of salt. Salterns (saltworks) are consisted with various salt making facilities such as roasting shed, saltern mound, salt field, salt well) salt pit or brine pit) and seawater reservoir. Among them roasting shed which is constructed chiefly with hundreds of pieces of pine tree as a frame and with straw as roof and wall is customarily considered as an unit of saltwork. And inside it is saltpan made of two kinds of materials, that is iron pan or plaster pan. The area attached to one unit of roasting shed is approximately 1 ha, and that of saltern mound is a tenth of it.

• The Korean Journal of Air & Space Law and Policy
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• v.20 no.2
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• pp.59-158
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• 2005

When a military aircraft suffers damages due to the defects in its design, manufacturing or notification, all of which are generally understood as products liability defects, the obvious compensation is sought as it would in other consumer good case. However, there exist clear yet unappreciated difference between general consumer goods and military aircraft, as far as products liability law is concerned - some sort of recovery should be obtained even when there exist only defects, not damages, to the aircraft because of the implication of defective parts is much grave than what can be expected in a consumer goods case. While certain anticipatory measures do exist in manual or at negotiation stages for the safety of military aircraft, such measures are ineffective, if not ambiguous, in recovery effort in the post-accident stage In another word, the standardized military procurement contract manuals and boilerplate forms do not appreciate the unique and dangerous military nature of military aircraft. There are many unique legal issues which can arise when trying to prevent defective aircraft or parts, or to recover compensations for accident due to such defects. At two-level, the government should establish legal system (or countermeasures if you'd like) for purchasing safer military aircraft. First, one should be able to work with legal ground and policy that allows selecting and purchasing safer goods - the purpose of such contract is not litigious, but rather in acquiring what are most reliable. Second, in case the defects do arise and lead to damages, solid legal principles and instructions should be established for effectively pursuing appropriate company, (usually a aerospace industry giant with much experience) for products liability - the purpose of such pursuit is inevitable for a public official, since he or she is no private business man with much flexibilities, even to the point of waiving such compensatory right for future business purposes. This article tries to identify problems in methods of procuring military aircraft or parts - after reviewing on how the military can improve on legal and policy grounds for procuring what will be the focus of future military strength, it will offer some of the ways to effectively handling and resolving a liability issues.