• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.574-576
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• 2008

Now there are two types Non-contact compensation AC automatic voltage regulator (A.V.R). One is transformer compensation regulator, whose principle is the combination of multiple compensation transformers, do the compensation by turning on and off the connections of the transformer through the multi-full bridge circuit. This method removed the mechanical drive and contacts, which increases the life and the dynamic performance of the A.V.R. However, the compensation is multilevel, and it needs many compensation transformers and switches, the circuit is complex, the compensation precision is low. Another type is PWM switch AC regulator, whose principle is getting the AC voltage from the input, then induce the AC compensation voltage through commutating and high frequency PWM transforming, and phase tracking. Here the compensation is step-less, the compensation precision is high, and the response is fast. But the circuit is complex, and it needs an inverse compensation transformer, which is difficult to realize high-power applications. In this paper, it shows an Automatic Voltage Regulator which use high frequency PWM inverter do compensation. This A.V.R has the function as the custom-power, which make the performance of the power supply in a high level.

• Journal of Powder Materials
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• v.25 no.1
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• pp.19-24
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• 2018

Cu-Fe alloys (CFAs) are much anticipated for use in electrical contacts, magnetic recorders, and sensors. The low cost of Fe has inspired the investigation of these alloys as possible replacements for high-cost Cu-Nb and Cu-Ag alloys. Here, alloys of Cu and Fe having compositions of $Cu_{100-x}Fe_x$ (x = 10, 30, and 50 wt.%) are prepared by gas atomization and characterized microstructurally and structurally based on composition and powder size with scanning electron microscopy (SEM) and X-ray diffraction (XRD). Grain sizes and Fe-rich particle sizes are measured and relationships among composition, powder size, and grain size are established. Same-sized powders of different compositions yield different microstructures, as do differently sized powders of equal composition. No atomic-level alloying is observed in the CFAs under the experimental conditions.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.2
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• pp.1-16
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• 1991

In order to see the possible effect of the functional load-bearing after osseointegration of the titanium root form implant in dog a histologic study was conducted. One side of lower jaw was surgically prepared edentulousness and titanium implants were inserted. Some implants were functionally loaded through fixed detachable prosthesis and some are isolated and unloaded. The dog was sacrificed four months later and bone sections with implants were processed for histologic evaluation and the results were as follows ; (1) The bone to implant interface after four months of load bearing presented no mobility and no marginal bone loss radiographically and histologically. (2) The interface zone between compact bone and implant revealed a direct bone to implant contact and in some areas marrow tissue contacts were examined at the light microscopic level. (3) At the ultrastructural level the interface of surrounding compact bone matrix and implant, three types of superficial layers were found ; one with moderate electron dense amorphous granular substance layer, other with high electron dense fine granular substance layer, and another type of amorphous granular substance covered with high electron dense line of minute granules. (4) The osteoblasts in the marrow tissue neighboring implants and osteocytes in compact bone showed typical normal characteristics and in the marrow tissues some of lymphocytes and mast cells were observed. (5) The abscence of abnormal tissue reactions at a cellular level indicates a high degree of biocompatibility for the experimental titanium implant and basically no difference was found between functionally loaded and unloaded implants.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.09a
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• pp.261-278
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• 2003

Concepts.Wafer-Level Chip-Scale Concept with Handling Substrate.Low Accuracy Placement Layout with Isolation Trench.Possible Pitch of Interconnections down to $10{\mu}{\textrm}{m}$ (Sn-Grains).Wafer-to-Wafer Equipment Adjustment Accuracy meets this Request of Alignment Accuracy (+/-1.5 ${\mu}{\textrm}{m}$).Adjustment Accuracy of High-Speed Chip-to-Wafer Placement Equipment starts to meet this request.Face-to-Face Modular / SLID with Flipped Device Orientation.interchip Via / SLID with Non-Flipped Orientation SLID Technology Features.Demonstration with Copper / Tin-Alloy (SLID) and W-InterChip Vias (ICV).Combination of reliable processes for advanced concept - Filling of vias with W as standard wafer process sequence.No plug filling on stack level necessary.Simultanious formation of electrical and mechanical connection.No need for underfiller: large area contacts replace underfiller.Cu / Sn SLID layers $\leq$ $10{\mu}{\textrm}{m}$ in total are possible Electrical Results.Measurements of Three Layer Stacks on Daisy Chains with 240 Elements.2.5 Ohms per Chain Element.Contribution of Soldering Metal only in the Range of Milliohms.Soldering Contact Resistance ($0.43\Omega$) dominated by Contact Resistance of Barrier and Seed Layer.Tungsten Pin Contribution in the Range of 1 Ohm

• Women's Health Nursing
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• v.5 no.3
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• pp.389-409
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• 1999

This study was carried out to identify the differences between nursing needs and levels of satisfaction of postpartum women during the early postpartum period. The goal of this study was to obtain needed to develope the nursing quality for postpartum women. The subjects were 87 postpartum women who had vaginal delivery at 2 general hospital and 2 maternity hospital in the Ulsan City. The period for the data collection was from June 1 to 29, 1999. The data was gathered using an 98 items questionnaire which was a modified version of a questionnaire the developed by Y. J. Chun. Results found are as follows : 1. The general characteristics of the subjects : The majority of subjects were 25-29 yrs. (57.5%), high school and college graduates(96.5%), unemployed(75.9%), middle ranged economics(93.1%), had no religion(43.7%), male baby(52.9%), birth weight 3-3.5Kg(49.4%), wanted pregnancy(96.6%), no abortion history(50.6%), had antenatal care(89.7%), had prenatal education(32.2%), postnatal education(42.5%), intended breast feeding (46.0%), had resonable self confidence about self(20.7%), infant care(36.8%) and nuclear family pattern(82.3%). 2. The level of nursing needs of overall nursing care(3.93) and the levels of satisfaction(3.86) was relatively high. The nursing needs by category of nursing care, the highest need was in the emotional and psychological care(4.09), and the lowest need was in physical need(3.73). The satisfactions by category of nursing care, the highest satisfaction was in emotional and psychological care(4.11) and the lowest satisfaction was in education in self care(3.64). The significant differences between nursing needs and satisfactions were found on education in infant care(p=.005), and education in self care(p=.020). 3. Among items of physical care, 'accurate medication and treatment(4.21)', 'control of postpartum hemorrhage(4.13)', 'pain control and care of episiotomy wound (4.12)' and 'regular observation of postpartum conditions(4.09)' showed high nursing needs. 'Accurate medication and treatment(4.31)', 'regular observation of postpartum condition(4.24)', 'control of postpartum hemorrhage(4.22)' and 'pain control and care of episiotomy wound(4.12)' showed high satisfaction levels. 4. Among items of emotional and psychological care, 'personal treatment(4.32)', kind and faithful care(4.30)', 'detailed explanation on the treatment or nursing care(4.25)', 'adequate draping during the care and treatment(4.23)' and detailed explanation on a doubt(4.13)', showed high nursing needs, 'personal treatment(4.52)', 'kind and faithful care(4.45)', 'detailed explanation on a doubt(4.24)', 'detailed explanation on the treatment or nursing care(4.21)' and 'adequate draping during the care and treatment(4.18)' showed high satisfaction of nursing care. Difference between the level of nursing needs and satisfaction was significant except item of 'early contacts with their baby and breast feeding'. 5. Among items of environmental care, the highest level of need and satisfaction were on the items of 'neat bedding and clothes(4.05, 4.21)' and 'room cleansing or care of room(4.01, 4.28)'. Differences between the level of nursing care and satisfaction were 'room cleansing of care of room'. 6. Among items of educational needs on self care, 'sitz bath method(4.22)', 'high risk symptoms to immediate clinic visits(4.13)', 'the timing of tub bath(4.05)' and 'good secretion of breast milk(4.03)', showed high nursing needs, 'sitz bath method(4.22)' showed high satisfaction of nursing care. Differences between the level of nursing care and satisfaction were 'the timing of hair shampoo', 'the timing of tub bath', ' the method of pad change', 'postpartum exercise', 'good secretion of breast milk', 'maintenance of breast figure', 'contraindicated drugs in postpartum women', 'kegel exercise' and 'breast self examination'. 7. Among items of educational needs on infant care, 'immunization of infants(4.36)', 'symptoms of sickness to immediate clinic visits(4.28)'. 'safety and emergency care(4.28)', 'umbilical care(4.26)', 'feeding times and intervals(4.24)', 'normal growth and development of infant(4.24)' and 'infection control(4.22)', showed high level of nursing care, 'immunization of infants(4.21)', 'feeding times and intervals(4.17)', were high satisfaction items showed significant differences between the level of nursing care and satisfaction. 8. Relationship between nursing needs and levels of satisfaction among postpartum women were as follows : 1) Physical area : There were no significant differences in the level of nursing needs, but satisfaction levels were significantly different among 'working mothers', 'baby's weights', 'baby's sex', 'planning of feeding' and 'routes of receiving postpartum informations'. 2) Emotional and psychological area : The level of nursing needs were significantly different in the area of 'confidence in self care'. Satisfaction levels were significantly different among 'baby's sex', 'baby's weights', 'the confidence of infant care' and 'working mother'. 3) Environment area : There were on significant differences in the level of nursing needs, but satisfaction levels were significantly different among 'maternal age' and 'baby's weights'. 4) Education in self care : The level of nursing needs were significantly different among 'parity history' and 'type of family formation'. Satisfaction levels were significantly different among 'working mother', 'baby's sex', 'antenatal care', 'postpartum education', 'planning of feeding', 'routes of receiving postpartum informations'. 5) Education in infant care area : The level of nursing needs were significantly different among 'parity history'. Satisfaction levels were significantly different among 'baby's sex', 'receiving postpartum education or not' and 'working mother'.

• The korean journal of orthodontics
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• v.41 no.2
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• pp.112-120
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• 2011

Objective: Microscrew implants (MSls) offer many advantages, but some complications are known to occur during their insertion. One of the most commonly reported complications is root injury. Our aim was to identify factors associated with root injury and to evaluate their qualitative and quantitative values. Methods: Thirty-five orthodontists placed MSls (AbsoAnchor$AbsoAnchor^{(R)}$, Dentos Co. Ltd, Daegu, Korea) in the upper jaw of typodonts, labially between the second premolar and the first molar, in low and high vertical positions. Root contacts were counted, and distances between MSI apices and roots were measured. Fear level of the orthodontists was surveyed before and after the experiment. Wilcoxon's test, chi-square test, and Mann-Whitney test were used for statistical analysis. Results: Overall root contact rate of MSI insertion was 23.57%. The root contact rate was significantly higher in MSls inserted at $90^{\circ}$ (45.71%) than at $30^{\circ}$ (1.43%). The distance between the dental root and MSI also increased significantly in MSls inserted at $30^{\circ}$. Mean fear level before MSI insertion (4.6) significantly decreased after insertion (3.2); the causative factors were risk of injury to dental root and maxillary sinus or mandibular canal. Conclusions: Root injury is relatively rare, and oblique angulation reduces the risk of root and MSI contact.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.42 no.4
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• pp.116-125
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• 2019

The Dynamic Vehicle Routing Problem (DVRP) involves a combinatorial optimization problem where new customer demands become known over time, and old routes must be reconfigured to generate new routes while executing the current solution. We consider the high level of dynamism problem. An application of highly dynamic DVRP is the ambulance service where a patient contacts the service center, followed by an evaluation of case severity, and a visit by a practitioner/ ambulance is scheduled accordingly. This paper considers a variant of the DVRP and proposes a decentralized algorithm in which collaborators (Depot and Vehicle), both have only partial information about the entire system. The DVRP is modeled as a periodic re optimization of VRP using the proposed decentralized algorithm where collaborators exchange local information to achieve the best global objective for the current state of the system. We assume the existence of a dispatcher e.g., headquarter of the company who can communicate to vehicles in order to gather information and assigns the new visits to them. The effectiveness of the proposed decentralized coordination algorithm is further evaluated using benchmark data given in literature. The results show that the proposed method performed better than the compared algorithms which utilize the centralized coordination in 12 out of 21 benchmark problems.

• Women's Health Nursing
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• v.3 no.1
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• pp.5-27
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• 1997

This study was carried out to identify the difference between nursing needs and levels of satisfaction of primiparae during the early postpartum period. The goal of the study was to obtain data needed to develope maternal education programs and to improve the nursing quality for primipara. The subjects were 111 primiparae who had normal delivery at 2 general hospitals in the Seoul area. The data was gathered using an 81 items questionnaire which was developed by the researcher from Nov. 30, 1995 to Feb. 5, 1996. Results found are as follows : 1. The characteristics of subjects : The majority of subjects were aged 26-30yrs(60.4%), high school graduated(49.5%), jobless(52.3%), had no religion(49.5%), no antenatal(74.5%), and postnatal education on self and infant care(55.9%). A large proportion of primiparae intended to feed breast milk(49.5%) but in fact only 7.2% fed breast milk while in the hospital. Many subjects perceived that they had reasonable self confidence about self care(46.8%), and infant care(36%). 2. The level of nursing needs of overall nursing care was relatively high(Mn 3.98) but the level of satisfaction was of average level(Mn 3.09). Therefore, difference between the level of nursing needs and satisfaction was significant(p=0.0001). 3. The nursing needs by category of nursing care the highest need was on the education of infant care(4.29), the lowest was on physical care(3.80). The level of satisfaction was higher on environmental care(3.40) and physical care(3.32). But the category that showed the lowest satisfaction was education of infant care(2.67). Hence, difference of categories between the level of nursing needs and satisfaction was significant(p=0.0001). 4. Among items of physical care, observation of primiparas' conditions(4.21), accurate medication and treatment(4.18), care of breast engorgement(4.07) and control of postpartal hemorrage(4.01) showed high nursing needs. On the other hand, only the level of satisfaction was higher on accurate medication and treatment(3.82). The rest of items revealed only average level of satisfactions. Difference of items between the level of nursing needs and satisfaction was significant(p=0.0001) except items of dietary care. 5. Among items of psychological care, 8 items of nursing needs were high(3.72-4.29), expecially detailed explanation on which mothers want to know(4.29), treatment and nursing care they receive(4.23), kind and faithful care(4.22), early contacts with their baby(4.20), and adequate draping during the care and treatment(4.18). Among items of psychological care higher satisfactions were shown on items of kind and faithful care(3.80), personal treatment(3.70), and detailed explanation to mothers, but the least satisfied items was early contact with baby(2.13). Difference between the level of nursing needs and satisfaction was significant(p=0.0001). 6. Among items of environmental care, the highest level of need and satisfaction was on the items of neat bedding and pajamas(3.54). The difference was significant (p=0.0001). 7. Among the items of educational needs on self care, all of 22 items revealed higher educational needs(3.50-4.33) but the levels of satisfaction varied with a range of 2.63-3.42. Among the items the satisfactions were high on items of breast care including massages(3.42), perineal care(3.36) and expression of breast milk(3.32). Less satisfied items were drugs not be taken by breast milk feeder(2.63), maintenance of breast figure(2.76) and postpartum exercise(2.80) and so on. The difference was significant(p=0.0001). maintain 8. Among the items of educational needs on infant care, 19 items revealed higher educational needs(3.28-4.54). And the highest need were on the 3 items of normal growth and development of infant, safety and emergency care, symptoms of sick(4.45) and the meaning of crying of the baby(4.52). The level of satisfaction among items of education of infant care ranged from 2.47 to 3.16. Most satisfied items were buriping(3.16), bathing(3.11) and diapering(3.09). The items of which the mother's needs were high revealed the lowest satisfaction level. The difference was significant (p=0.0001). 9. Relationship between nursing needs and levels of satisfaction among primiparae of different characteristics were as follows : 1) Nursing needs of physical and psychological areas were significantly different among different age levels but no relationship was found on other categories regardless of the level of satisfaction. 2) With regard to different levels of education, some relationship was found in nursing needs of psychological area(p=0.007), educational needs on infant care(p=0.04) and environmental care(p=0.01). Also, the difference of satisfaction level was significant. 3) Working mothers had higher nursing needs and were more satisfied on items of physical care(p=0.05), education on self care and infant care. Difference were significant between nursing needs and level of satisfaction. 4) With regards to different religion a moderate relation was found between nursing needs of environmental care infant care education but no relationship was found on levels of satisfaction. 5) With regards to antenatal education, the mothers who have had no antenatal education revealed higher nursing needs on physical care but those who had antenatal education were more satisfied with education on self care and infant care. The difference was significant. (p=0.0001). 6) With regards to postpartum education, the mothers who have had some sort of postpartum education revealed higher nursing needs on physical and self care. And they were more satisfied with nursing of every category except infant care than mothers who had not any postpartum education. Differences was significant between the nursing needs and levels of satisfaction.(p=0.0001). 7) With regards to breast feeding experience during the hospitalization, those who had no experience of breast feeding revealed higher nursing needs on physical care in contrast to breast feeders, who had higher educational needs on infant care. And breast feeder were more satisfied with all categories. Differences was significant(p=0.0001). 8) With regards to perception of self confidence on self care and infant care, no relationship was found on nursing needs and level of satisfaction in every category of nursing.

• Korean Journal of Materials Research
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• v.21 no.2
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• pp.89-94
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• 2011

In this work, fabrication and electrochemical analysis of an individual multi-walled carbon nanotube (MWNT) electrode are carried out to confirm the applicability of electrochemical sensing. The reactive ion etching (RIE) process is performed to obtain sensitive MWNT electrodes. In order to characterize the electrochemical properties, an individual MWNT is cut by RIE under oxygen atmosphere into two segments with a small gap: one segment is applied to the working electrode and the other is used as a counter electrode. Electrical contacts are provided by nanolithography to the two MWNT electrodes. Dopamine is specially selected as an analytical molecule for electrochemical detection using the MWNT electrode. Using a quasi-Ag/AgCl reference electrode, which was fabricated by us, the nanoelectrodes are subjected to cyclic voltammetry inside a $2{\mu}L$ droplet of dopamine solution. In the experiment, RIE power is found to be a more effective parameter to cut an individual MWNT and to generate "broken" open state, which shows good electrochemical performance, at the end of the MWNT segments. It is found that the pico-molar level concentration of analytical molecules can be determined by an MWNT electrode. We believe that the MWNT electrode fabricated and treated by RIE has the potential for use in high-sensitivity electrochemical measurement and that the proposed scheme can contribute to device miniaturization.

• Economic and Environmental Geology
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• v.53 no.3
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• pp.259-269
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• 2020

The use of the geophysical method in mining prospecting has been studied in the Asdaf region (South-East of Morocco). The objective of the study is to examine the aptitude of the electrical technique, in this case induced polarization (IP) and electric tomography, combined with the electromagnetic method (VLF), in the exploration of barite . The result obtained by the pseudo-sections of electrical tomography and that of KH filtration highlighted anomalies of resistant contact (greater than 400Ω.m) and of high charge chargeability (5mV / V). These contacts are hosted in less resistant Devonian age shale and sandstone. The resistivity response obtained at their level is characteristic of the venous structures associated with barite mineralization. The direction of the mineralized veins is parallel to the direction of the fractured zones (NE-SW), which indicates that the mineralization in place is due to the tectonic movements of the Hercynian orogeny (from Devonian to Permian). These veins are aligned with the locations of abandoned mine shafts and with surface mining areas. Geophysical technique therefore seems to play a key role in barite mining exploration.