• Journal of Technologic Dentistry
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• v.21 no.1
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• pp.27-41
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• 1999

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-30Pd-10Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at 350-$550^{\circ}C$ Age-hardening characteristic of the small Au-containing Ag-Pd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, energy dispersed spectra and electron probe microanalysis. Principal results are as follows ; Maximum hardening occured in two co-phases of ${\alpha}_2$ + PdCu In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase($L1_o$ type) and an Ag-rich ${\alpha}_2$ phase occurred and a discontinuous precipitation occurred at the grain boundary. From the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu redered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}{\to}{\alpha}_1+PdCu{\to}{\alpha}_2+PdCu$ at Pd/Cu = 3 Pd element of Ag-Pd-Cu alloy is more effective dental alloy on anti-corrosion and is suitable to isothermal ageing at $450^{\circ}C$.

• Journal of Korean Society of Forest Science
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• v.1 no.1
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• pp.22-29
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• 1962

(1) The objects of this study are to observe the possibility of regenerating a young merchantable pitch pine stand by sprouts and to compare the growth trend of sprouts with that of seedlings of same age grown under the almost same circumstances. (2) A plot of 20 year old pitch pine plantation, i.e. 200 trees on 0.1 ha of average D.B.H. 14 cm was clearcut at 20 cm above ground in April, 1945. By the late spring of that year sixty per cent of the cut stumps had sprouted. (3) Fourty to eighty sprouts were found on each stump (maximum:412 sprouts) at the first, but many of them had gradually died out leaving only four to five sprouts per stump by the time of three years after cutting. At that time only one vigorous sprout was left per stump by eliminating the weaker ones. (4) The sprouts, as they grew, started to cover the old stumps with new tissues developed from lower part of sprouts;consequently forming new root systems from the base of new tissues, and they appeared to be seedlings. When the age of sprouts was thirteen years old, the old stumps were completely decayed away and the reproduced stand from sprouts was averaged at 9.7 cm in D.B.H. and at 5.5m in height. (5) When the age of sprouts was thirteen years old, the sprouts exceeded the seedlings in both of total present growth and mean annual increment in height, volume, D.B.H. and basal area, but the seedlings began to exceed the sprouts in current annual increment of height, volume, D.B.H. and basal area at about ten years of age. The rates of increment of the seedling in height, volume, ect. were larger than those of sprouts except when they were one to four years old. From above facts, the following may be concluded: (1) In regenerating a pitch pine stand by sprouts, the lower the stump height, the better the result. (2) If no light limit exists, regenerating a pitch pine stand by sprouts is well possible even at the age of 20 year. (3) Pitch pine reproduction started from sprouts exceeds the seedlings of same age in growth under the almost same circumstances until they get ten years of age.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.185-202
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• 2020

The diapause induction season in Ostrinia furnacalis (Lepidoptera: Crambidae) was estimated in Suwon. Three batches of adult generations were observed, the first one from early May to early July, the second from early or mid-July to early or mid-August, and the third from mid-August to October. In outdoor larval rearing, colony rearing occurring from mid-July to mid-August produced both non-overwintering and overwintering larvae, whereas late-reared colonies produced only overwintering larvae. Larvae collected during July and August in maize fields produced both non-overwintering and overwintering larvae, whereas late-collected larvae produced only overwintering larvae. The results indicated that O. furnacalis has a bi- or trivoltine complex life cycle in this area. In the laboratory, when larvae of all instars within 9 h after molting were first treated to a diapause induction condition (11:13 h = light:dark photoperiod and 20℃), almost all larvae were induced to diapause. However, when similar treatments were conducted age-specifically for the 5th instar larvae, diapause induction rates in 3- and 4-day-old larvae of the 5th instar decreased. In contrast, when larvae were subjected to the diapause induction treatment only during the periods from the hatching stage to the 2nd, 3rd, and 4th instar, almost all larvae were not induced to diapause. The results suggest that the early age of the 5th larval instar is the last stage for sensitivity to diapause induction stimuli. In the diapause-induced larvae, hemolymph trehalose content increased and body supercooling points dropped, compared with those in non-diapause larvae.

• Journal of East-West Nursing Research
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• v.8 no.1
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• pp.113-125
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• 2003

This study is a descriptive investigation into the image of nurses, and attempted to help to advance the profession of nursing and to provide basic data for developing strategies to improve the image of nurses. The Subject of this study was a group of 380 persons from a K Medical Centre in Seoul, including the hospital patients and their guardians, as well as the doctors, assistants and hospital administrative staff. The data have been collected from the 10th to the 30th of May, 2003. We have developed a research tool of 40 questions divided into three categories using a tool developed by Kim, H.J and KIm, H.O.(2001) verifying its construct validity. The reliability of the tool was Cronbache's ${\alpha}=.97$, and by categories, Cronbach's ${\alpha}=.86$ for service image, Cronbach's ${\alpha}=.96$ for professional image and Cronbache's ${\alpha}=.90$ for social image. The collected data have been analysed according to the purpose of this study using SPSS WIN 11.0 for real number, percentage, factors analysis, multiple regression analysis, ANOVA and $x^2$-test, and the results are as follows: 1) There was a significant difference in the image of nurses by job series of the subjects; from patients and guardians for 4.01 to doctors 3.62, assistants 3.54 and staff members 3.41 (F=36.14, p=.000). As well, there was a significant difference in service, professional and social image categories according to the position of the subjects ($F=20.36{\sim}42.35$, p=.000). 2) The main factors that affect on formation the nurse's imaging came by direct experiences with nurses at hospitals for 81.3%, by looking at the every life of the nurses that the subjects personally know for 15.5%, by mass media for 1.6% and by the accounts from the others for 1.6%. 3) 78.4% of the subjects considered that the image of nurses on mass media is described better than for real, 8.2% believed that the image is described worse than for real, and only 13.2% of the subjects perceived that the image of nurses on mass media corresponds the image of nurses in actual life. 4) 74.5% of the subjects said that they got a better image of nurses after their hospitalization while 2% got a worse one and 23.5% said to have had no changes, and the period of hospitalization had no relevance to the image of nurses (X2=5.04, P=.489). However, while 16.8% of the subjects who spent less than one week in hospital said that they got a better image of nurses, 27.5% of those who spent longer than four weeks got a better image of nurses. 5) There was a significant difference in the total image points of nurses by the patients and their guardians according to the period of hospitalization; 4.14 for 1 to 2 weeks, 4.07 for 2 to 4 weeks, 4.02 for 4 weeks and longer and 3.80 for less than a week (F=3.40, P=.019). Upon the results stated above, I should like to propose as below: 1) An investigative enquiry is needed to improve the image of nurses as though being a nurse is very hard and difficult. 2) A continuous monitoring in mass media is needed to create a positive image of nurses.

• Korean Journal of Weed Science
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• v.16 no.3
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• pp.210-220
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• 1996

Ten-day-old seedlings of the oxyfluorfen-tolerant and -susceptible rice cultivars with barnyardgrass, a typical susceptible weed were soaked in oxyfluorfen at $10^{-6}M$ for 2 hrs kept for 24 hrs in the dark, and exposed to light for 0, 2, 4, or 6 hrs to investigate changes in the activity and isozyme of antioxidative enzymes. The activities of antioxidative enzymes of APOX, CAL, POX, NR, GR, MDAR and SOD in the tolerant and susceptible rice cultivate themselves didn't show any difference but the activity in the susceptible barnyardgrass was very low in comparison with rice cultivars. The activity of lipoxygenase tended to be some slightly higher in the susceptible rice cultivars and barnyardgrass than in the tolerant rice cultivars. The activities of MDAR, POX, GR and SOD, antioxidative enzymes, were higher in the tolerant rice cultivars than in the susceptible rice cultivars and barnyardgrass after the treatment of oxyfluorfen. After the treatment of oxyfluorfen, in the change of POX isozyme, the activity of C band in the tolerant rice cultivars increased with increased concentration but it didn't in the susceptible rice cultivar. The activity of B band decreased slightly at $10^{-4}M$ in the susceptible barnyardgrass. Isozyme of GR, SOD and AO by the treatment of oxyfluorfen, the activity of each band between the tolerant and susceptible rice cultivars showed no difference but GR isozyme C band was disappeared in the susceptible barnyardgrass at $10^{-4}M$. In the change of esterase isozyme resulting from the treatment of oxyfluorfen, the activities of B, C and D bands decreased more in the susceptible rice cultivars than in tolerant rice cultivars, and A band was disappeared in the susceptible barnyardgrass at $10^{-4}M$.

• Economic and Environmental Geology
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• v.31 no.3
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• pp.201-213
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• 1998

From the Jungwon and Munkyeong areas which are among the famous producers of the carbonate-type groundwaters in Korea, various kinds of natural waters (deep groundwater, shallow groundwater and surface water) were collected between 1996 and 1997 and were studied for hydrogeochemical and environmental isotope (${\delta}^{34}S_{so4}$, ${\delta}^{18}O$, ${\delta}D$)systematics. Two types of deep groundwaters (carbonate type and alkali type) occur together in the two areas, and each shows distinct hydrogeochemical and environmental isotope characteristics. The carbonate type waters show the hydrochemical feature of the 'calcium(-sodium)-bicarbonate(-sulfate) type', whereas the alkali type water of the 'sodium-bicarbonate type'. The former type waters are characterized by lower pH, higher Eh, and higher amounts of dissolved ions (especialJy, $Ca^{2+}$, $Na^{+}$, $Mg^{2+}$, $HCO_3{^-}$ and $SO_4{^{2-}}$). Two types of deep groundwaters are all saturated or supersaturated with respect to calcite. Two types of deep groundwaters were both derived from pre-thermonuclear (about more than 40 years old) meteoric waters (with lighter 0 and H isotope data than younger waters, i.e., shallow cold groundwaters and surface waters) which evolved through prolonged water-rock interaction. Based on the geologic setting, water chemistry, and environmental isotope data, however, each of these two different types of deep groundwaters represents distinct hydrologic and hydrogeochemical evolution at depths. The carbonate type groundwaters were formed through mixing with acidic waters that were derived from dissolution of pyrites in hydrothermal vein ores (for the Jungwon area water) or in anthracite coal beds (for the Munkyeong area water). If the deeply percolating meteoric waters did not meet pyrites during the circulation, only the alkali type groundwaters would form. This hydrologic and hydrogeochemical model may be successfully applied to the other carbonate type groundwaters in Korea.

• Archives of design research
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• v.19 no.2 s.64
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• pp.53-62
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• 2006

E-mail has indeed developed from 'a means of instant communication' to an indispensable part of online marketing. Therefore, companies need to implement consistent customer management. Communication with customers and marketing through e-mail is a powerful way of communication and adapting one-to-one marketing strategies to customer trends, habits and taste preferences. Since setting accurate targets is especially important in the fashion industry, e-mail marketing is the most effective way to communicate with customers and one-to-one marketing constitutes a very important strategy. In this study, I will analyze this powerful one-on-one marketing tool, particularly actual e-mail messages sent by an Internet Shopping Mall from June 12 to July 30, 2005, examine the effect of these messages on sales growth and analyze actual feedback received. Regarding e-mail read rates broken down by age and gender, 1 found that females in their late twenties recorded the highest rate at 21.66% and their contribution to sales growth was recorded at 3.5% From actual sales records, found that 28.10% of total sales were attributable to people in their late twenties, showing that the age group that reads e-mails the most also buys the most. Regarding feedback by e-mail title, e-mails from the 'Casual' category seemed to be the most effective, in that most of these e-mails were read. Also, messages sent on Tuesdays were read the most, according to the feedback analysis by weekday. Section e-mails were read more often than regular e-mails. Regarding the view rate according to the time e-mails were sent, messages sent to females in their late twenties at two o'clock in the afternoon were read by 20.93% of recipients, recording the highest read rate. By offering informative content and practical tips, visitors will be attracted to the site and generate site traffic. Therefore, we can conclude that sending e-mail messages can greatly contribute to sales growth and e-mail marketing is very effective. Also, in order to make e-mail campaigns more effective and improve marketing results, we need to analyze actual results and apply our findings in future e-mail campaigns. With this, we get successful marketing results.

• Korean Journal of Poultry Science
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• v.32 no.1
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• pp.9-14
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• 2005

This study was conducted to investigate the effects of Bacillus subtilis on the egg qualify, blood characteristics and fecal $NH_3-N$ in laying hens. A total of two hundred fifty two laying hens were randomly allocated into three treatments with seven replications for six weeks. Dietary treatments included 1) CON (control; basal diet), 2) BS0.2(control + $0.2\%$ Bacillus subtilis) and 3) BS0.4 (control +$0.4\%$ Bacillus subtilis). For overall Period, hen-day egg production tended to increase by the Bacillus subtilis $0.4\%$ in the diets, but was no significant difference. Egg weight, egg shell breaking strength, egg shell thickness, Haugh Unit, yolk color unit and egg yolk index were not affected by treatments. Difference of egg weight and egg shell breaking strength in the BS0.2 treatment tended to increase without significant difference. Difference of egg yolk index in laying hens fed Bacillus subtilis was increased (P<0.05). The concentrations of red blood cell (RBC) and white blood cell (WBC) were not significant difference. $NH_3-N$ concentration in feces with BS0.4 treatment was significantly (P<0.05) lower than control. In conclusion, dietary Bacillus subtilis could decrease fecal $NH_3-N$.

• Animal Systematics, Evolution and Diversity
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• v.14 no.4
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• pp.341-355
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• 1998

Thirty one morphometric characters of specimens in 15 subspecies of striped field mouse(Apodemus agrarius Pallas) from Eurasia were analyzed to clarify taxonomic status of these subspecies. Five major subgroups in A. agrarius were revealed: I, a largest-size form, specimens from two southern from other six localities in Korea, subspecies coreae and pallescens; III, the other large-size from, specimens from Astrachan in western Russia, subspecies volgensis; IV, a medium-size form, specimens from 16 localities in eastern Asia(North Korea, China, and eastern Russia), subspecies coreae, manchuricus, pallidior, ningpoensis, and insulaemus; V, a small-size form, specimens from 16 localities in western Asia and Europe (Kazakhstan, Russia, Lithuania, and Ukraine), subspecies tianschanicus, ognevi, agrarius, septentrionalis, nikolski, caucasicus, and karelicus. From this morphometric analyses, the followings are concluded: subspecies chejuensis is a larger-size form, as noted by Johnson and Jones(1955): subspecies pallescens is the synonym of subspecies agrarius, as suggested by Koh(1986): subspecies coreae from Korea is a large-size form and is idistinct from other 12 subspecies in Eurasia: the eastern form of subspecies ningpoensis by Corbet(1978) is a medium-size form o subspecies manchuricus, pallidior, ningpoensis, and insulaemus from eastern Asia (China and eastern Russia), and it includea North Korea specimens: a small-size form from western Asia and Europe(subspecies tianschanicus, ognevi, agrarius, septentrionalis, nikolski, caucasicus, and karelicus) is the western form of subspecies agrarius by Corbet(1978); the other large-size form of subspecies volgensis from western Russia is a distinct subspecies, which differs from the western subspecies agrarius. Therefore, it is concluded that 15 subspecies of A. agrarius can be classifed into five subspecies (chejuensis, coreae, ningpoensis, agrarius, and volgensis), although it is necessary to measure and analyze morphometric characters of specimens of other seven subspecies(albostriatus, maculatus, rubens, kahmanni, henrici, gloveri, and harti) for the complete reclassification of this species).

• Korean Journal of Veterinary Research
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• v.10 no.1
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• pp.11-23
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• 1970

Recently Carter(1952) reported the capsule antigens of Pasteurella multocida could be divided into four serological types A,B,C and D by means of precipitation tests. Subsequently he showed that the most sensitive for identification of these types involved the use of capsule substance adsorbed by erythrocytes in hemagglutination test. It may be somewhat difficult to conduct the hemagglutination test in small laboratory, because relatively large amounts of antisera and erythrocytes of the human O type are required for the test. A simple method for serological typing of P. multocida was the slide agglutination test employed by Little et al. (1943) and Namioka et al. (1962), but this method is still in controversy. The author tried adapting Carter's hemagglutination method to the slide method so called "micromethod technique", and studied on the stabilization of erythrocytes for use of slide hemagglutination to P. multocida although many invesigators reported the stabilization of erythrocytes. The results obtained are summarized as follows: 1. A simplified method (slide method) for capsule typing of the organism was developed by adapting Carter's hemagglutination reaction(tube method). Antibody-containing serum can be diluted serially on Boerner's microtest slide with capillary or serological pipetts with a considerable accuracy. The slide reaction can be carried out with case on the slide by adding $0.05m{\ell}$ of antigen-sensitized erythrocytes suspension diluted to one percent on $0.05m{\ell}$ of serially diluted antibody-containing sera, and the final result can be read after 60 minutes at the room temperature ($15^{\circ}C$). 2. It is difficult to determine superiority of inferiority between the slide method and the tube method on the pattern of the reaction of hemagglutination. 3. The pH range of 6.6 to 8.3 is optimal for the slide hemagglutination reaction. 4. The antigen-sensitization against erythrocytes at $37^{\circ}C$ is optimal for the slide hemagglutination. 5. Both the doses and concentration of antigen do not influence the antigen-adsorbing capacity of erythrocytes. 6. The reduction of antigen-sensitizing hours does not influence the antigen-adsorbing capacity of erythrocytes even 30 minutes. 7. The tannic acid treatment against formalinized and non-formalinized erythrocytes showed no effect on the reaction of hemagglutination. 8. The erythrocytes preserved at $4^{\circ}C$ in the ACD solution do not decrease the reactivity on the reaction of hemagglutination for 60 days, while they begin slight hemolysis 30 days after preserving. 9. The stable preparation of erythrocytes can be obtained by treating the cells at $37^{\circ}C$ for 20 hours with from 4 to 8 percent of formalin in saline or buffer. These cells can be preserved at $4^{\circ}C$ for more than 8 months experimented without hemolysis. With low concentration of formalin, the cells were not sufficiently stabilized resulting in the hemolysis after short period of preservation at $4^{\circ}C$. 10. The erythrocytes treated with 16 percent of formalin remain constantly or increase the reactivity for the reaction of hemagglutination. On the contrary, the cells treated with I to 8 percent of formalin decrease the reactivity. 11. There is no difference between nontreated fresh erythrocytes and the erythrocytes preserved in the ACD solution on the reactivity against the hemagglutination, and the erythrocytes treated with 16 percent of formalin showed the reactivity of higher level than that of the above two kinds of erythrocytes. 12. There is no difference between the saline and the isotonic buffer solution on the reaction of hemagglutination.