• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.1
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• pp.146-154
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• 2007

In this paper, we have presented a real-time transfer mechanism for the delay-sensitive data in WSNs (Wireless Sensor Networks). The existing methods for real-time data transfer select a path whose latency is shortest or the number of hops is least. Although the approaches of these methods are acceptable, they do not always work as efficiently as they can because they had no consideration for the link error rates. In the case of transmission failures on links, they can not guarantee the end-to-end real-time transfer due to retransmissions. Therefore, we have proposed an algorithm to select a real-time transfer path in consideration of the link error rates. Our mechanism estimates the 1-hop delay based on the link error rate between two neighboring nodes, which in turn enables the calculation of the expected end-to-end delay. A source node comes to choose a path with the shortest end-to-end delay as a real-time route, and sends data along the path chosen. We performed various experiments changing the link error rates and discovered that this proposed mechanism improves the speed of event-to-sink data transfer and reduces delay jitter. We also found that this mechanism prevents additional energy consumption and prolongs network lifetime, resulting from the elative reduction of transmission failures and retransmissions.

• The Journal of Society for e-Business Studies
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• v.16 no.4
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• pp.139-154
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• 2011

Recently Internet keyword search service providers tends to use CPC advertizement method rather than CPM method. However researches how much the CPC method is beneficial to advertisers than CPM method in certain perspectives are insufficient and not performed systematically. So this paper tries to do comparative analysis about the two methods by analyzing the real transactional DB data from an advertizement agency. Due to the difficulties of direct comparison between the two methods because of their different expose positions on the Web and different types of attributes in DB, we did some preprocessing step for the transactional data. From the result of analysis, the click rate of CPC is higher than CPM by 1.3% and the unit cost for the CPC per one click is lower than CPM method by 51 Won. It shows the CPC method is more effective than CPM method for advertizement from the point of advertizement effectiveness (CTR) and advertizement cost (CPC). We hope this research would give useful information to advertisers and marketing managers in making advertizement strategy, marketing decision and budgeting.

• Journal of the Korean Chemical Society
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• v.28 no.3
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• pp.149-154
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• 1984

The electrical conductivity of p-type yttrium sesquioxide has been measured as a function of temperature and of oxygen partial pressure at temperatures from 650 to 1050$^{\circ}C$C and oxygen partial pressures from $1 {\times}10^{-5}\;to\;2{\times}10^{-1}$atm. Plots of log conductivity vs. 1/T at constant oxygen partial pressures are found to be linear with low-and high-temperature dependences of conductivity. The high-temperature dependence of conductivity shows two different defect structures. The plots of log conductivity vs. log $Po_2$ are found to be linear at $Po_2$'s of $10^{-5}\;to\;10^{-1}$ atm. The electrical conductivity dependences on $Po_2$ are found to be ${{\sigma}{\propto}Po_2}^{1/6}$at $850{\sim}950^{\circ}C,\;{{\sigma}{\propto}Po_2}^{3/16}$ at $950{\sim}1050^{\circ}C\;and\;{{\sigma}{\propto}Po_2}^{1/7.5}{\sim}{{\sigma}{\propto}Po_2}^{1/8.3}\;at\;650{\sim}800^{\circ}C$, respectively. The defect structures are$O_i{''}$ at $850{\sim}950^{\circ}C$ and $V_M{'''}$ at $950{\sim}1050^{\circ}C$. The electron hole is main carrier type, however, ionic contribution is found at lower temperature portion.

• Journal of the Korean Chemical Society
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• v.47 no.2
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• pp.147-154
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• 2003

In this study, the fluorinated carbon blacks(CB) were used to reduce the negative temperature coefficient (NTC) phenomenon of the CB-filled high density polyethylene(HDPE) compounds in the fluorination pressure of 0.1-0.4 MPa. The changes in surface properties of the CB were investigated by using FT-IR, XPS and contact angle measurements. From the FT-IR results, the fluorinated CB showed the C-F absorption peak at 1400-1000 cm$^{-1}$ and the peak intensity was increased with increasing the fluorination pressure. Also, the analysis of XPS spectra of the fluorinated CB indicated that fluorine content was increased with increasing the fluorination pressure. Meanwhile, the surface free energy of the fluorinated CB was decreased with increasing the fluorination pressure. Consequently, the increase of fluorine contents on CB made a disappearance of NTC behaviors of CB/HDPE compounds, which was probably due to the reduction of CB reaggregation after melting point of the HDPE, resulting from decreasing the surface free energy of CB particles.

• Korean Journal of Microbiology
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• v.24 no.2
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• pp.154-160
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• 1986

In order to develope interspecific fusion of the genus Cellulomonas capable of assimilation cellulose, the optimun conditions for the protoplast formation was investigated to examine the susceptibility of cell wall, between different species of the same genus using scanning electron microscope. The variation in the susceptibilities of Cellulomonas sp. CS 1-1 and C. flavigena to lysozyme treatment were considerably remarkable, although they belong to the same genus. The rate of protoplast formation of CS1-1 was 99.9% being treated with lysozyme $(100{\mu}g/ml)$ for 30 minute and that of C. flavigena was about 80% being treated at the concentration of $600{\mu}g/ml$ of lysozyme for 6 hours. The susceptibility of cell wall to the lysozyme treatment on protoplast formation of the strain, CS1-1 seems not to be depend on the cultural periods of cells. On the contrary, that of C. flavigena was considerably depend on the periods. Cells of C. flavigena at mid exponential phase could be more efficiently converted to protoplast cells than those at late exponential phase be done. The rate of the protoplast formation was 95%, when cells of C. flavigena at mid exponential phase were treated with lysozyme $600{\mu}g/ml$ for 6 hours and observed by SEM. In the evalution of protoplast formation of the CS1-1 results of counting method in plate after osmotic shock treatment were similar to the results of the direct observation method by means of SEM. But in the case of C. flavigena the latter method was much more reliable than the former, because the differences between the number of spheroplasts and protoplasts were not able to figure out on conuting the number of protoplast after osmotic shock tretment.

• Research in Community and Public Health Nursing
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• v.7 no.1
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• pp.154-169
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• 1996

Parish nursing is a community health nursing role developed in 1983 by Lutheran chaplain Granger Westberg. An increasing emphasis on holistic care, personal reseponsibility for a healthy lifestyle, and changes in healthcare delivery systems have undoubtedly facilitated the establishment and nurturance of an innovative nursing role in the community. Parish nurses are functioning in a variety of church congregations of various denominations. The parish nurse is a educator, a personal health counselor, a coordinator of volunteers. The parish nurses helps people relate to the complexed medical care system and assists people to integrate faith and health. The autors conducted a study on pastor's expectations from parish nurses. Results of this study will be useful to those instrumental in planning, initiating, supporting, and evaluating a parish nurses program The research was done on 130 pastors in Taegue and Kyong Sang Buck Do, of various ages ranging from their 20's to 60's: and pastoring churches of various sizes, ranging from under 100 to over 300 members. 94.6% agreed that they needed a parish nurse on their staff; and 86.2% said they wanted to start a parish nurse program in their churches if certain basic conditions were met. The pastors responded that some would hire the nurses on a full-time basis(22.3%), a part -time basis (37.7%) or use volunteer nurses (40%). The pastors said they would expect the following from a parish nurse: health counselling (80.0%) regular health check-ups (78.5%) health care for the elderly (78.5%) health information and education (72.3%) hospice care (72.3%) visiting sick church members at home (69.2%) arranging and training volunteers to help the seek (59.2%) health care for expectant mothers (50.0%) introducing and taking people to health care facilities (46.2%) The pastors were surveyed about specific areas of health education they would want the parish nurse to teach(for example, high blood pressure and heart disease prevention and management(76.2%) ; stress management(74.6%); and diabetes prevention and management(73.8%). The pastors were surveyed about specific areas of health counselling they would expect the parish nurse to do (for example, drug abuse, (73.1), alcohol abuse(64.6%), marriage conflict(60.0%), recovery after the loss of a loved one(56.9%), and women's conflict with parents-in-law(53.8%). The pastors were surveyed about types of things they would want included in regular health check-ups, what they would want a parish nurse to do on home visits, and what they would want included in home care for the elderly. They were also surveyed on what kind of spiritual care they would like parish nurses to give. Most (90.7%) wanted their parish, parishioners to be involved in the parish nurses program as volunteers, and in a variety of ways(such as visiting sick in their homes(68.5%) and helping with housework(63.1%) and taking sick people to health facilities(60%). Parish nurses role, activities, and boundaries of practice should be continuously monitored and refined and a 'case manager' should be conceptualized as an additional or all-encompassing role. An initial parish / community needs and readiness assessment should be done prior to establishing a program to detemine if the congregation is ready, willing, and able to support such a position for at least a 2 to 3 year period.

• Imaging Science in Dentistry
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• v.40 no.2
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• pp.69-74
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• 2010

Purpose : The research was performed to predict the three dimensional relationship between the impacted mesiodens and the maxillary central incisors and the proximity with the anatomic structures by comparing their panoramic images with the CT images. Materials and Methods : Among the patients visiting Seoul National University Dental Hospital from April 2003 to July 2007, those with mesiodens were selected (154 mesiodens of 120 patients). The numbers, shapes, orientation and positional relationship of mesiodens with maxillary central incisors were investigated in the panoramic images. The proximity with the anatomical structures and complications were investigated in the CT images as well. Results : The sex ratio (M : F) was 2.28 : 1 and the mean number of mesiodens per one patient was 1.28. Conical shape was 84.4% and inverted orientation was 51.9%. There were more cases of anatomical structures encroachment, especially on the nasal floor and nasopalatine duct, when the mesiodens was not superimposed with the central incisor. There were, however, many cases of the nasopalatine duct encroachment when the mesiodens was superimpoised with the apical 1/3 of central incisor (52.6%). Delayed eruption (55.6%), crown rotation (66.7%) and crown resorption (100%) were observed when the mesiodens was superimposed with the crown of the central incisor. Conclusion : It is possible to predict three dimensional relationship between the impacted mesiodens and the maxillary central incisors in the panoramic images, but more details should be confirmed by the CT images when necessary.

• Journal of Korean Medicine Rehabilitation
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• v.15 no.2
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• pp.141-154
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• 2005

Objectives : This study was planned to evaluate clinical status of the alopecia patients who had visited oriental medicine clinic. Methods : 80 patients with alopecia, who had visited oriental medicine clinic from January 2004 to August 2004, were examined. Results & Conclusions : 1. The kinds and incidences of Alopecia : androgenetic alopecia 57.5%(46/80), alopecia areatea 20.0%(16/80), telogen effluvium 16.3%(13/80), seborrheic alopecia 6.3%(5/80). 2. In distribution of sex, the rate of male to female was 1:1 and most patients belonged to 20-30 year old group. 3. The most common onset of age was adolescence(63.8%) and the most common duration of hair loss was 1 to 3 years. 4. Among the 30 male androgenetic alopecia patients, Hamilton's type 4 was most common and among the 16 female androgenetic alopecia patients, Ludwig's type II and III were most common. 5. Family history of baldness in Androgenetic alopecia and alopecia areata were 56.5% and 25.0%, respectively. 6. Self-conscious causes of hair loss : stress(48.8%), irregular eating habits(21.3%), and lack of sleep(20.0%). 7. Associated diseases with alopecia patients : chronic neck pain(58.8%), temporomandibular disorders(55.0%) and seborrheic dermatitis(20.0%). 8. Associated symptoms with alopecia Patients : stress(78.8%), sleep disorders(68.8%), irregular eating habits(55.0%), Hot flush(43.8%), Stool disorders(43.8%), cold hands and feet(37.5%) and menstruation disorders(31.3%). 9. The most common scalp type was oily scalp(70.0%) and the symptoms of scalp were iching, dandruff, pain, inflammation. 10. $Bi{\grave{a}}n$ $zh{\grave{e}}ng$(辨證) of alopecia patients : $xu{\grave{e}}-r{\grave{e}}-f{\bar{e}}ng-z{\grave{a}}u$(血熱風燥) (25.0%), $g{\bar{a}}n-sh{\grave{e}}n-b{\grave{u}}-z{\acute{u}}$(肝腎不足) (23.8%), $shi-r{\grave{e}}-sh{\grave{a}}ng-zh{\bar{e}}ng$(濕熱上蒸) (16.3%), $xu{\grave{e}}-r{\grave{e}}-sh{\bar{e}}ng-f{\bar{e}}ng$(血熱生風) (13.8%), $xu{\grave{e}}-x{\bar{u}}-f{\bar{e}}ng-z{\grave{a}}u$(血熱風燥) (13.8%), $y{\bar{u}}-xu{\grave{e}}-z{\check{u}}-lu{\grave{o}}$(瘀血阻絡) (7.5%).

• Journal of Korean Medicine Rehabilitation
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• v.30 no.4
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• pp.143-154
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• 2020

Objectives To analyze the prognosis of patients with low back pain according to the severity of abnormal lumbar lordotic angle and Ferguson's angle. Methods Data from electronic medical record of a total of 199 patients hospitalized in Korean medicine hospital were analyzed. With the sagittal view of lumbar spine X-ray, lumbar lordotic angle was defined as the angle between the superior endplate of L1 with the inferior endplate of L5. Ferguson's angle was defined as the angle between the superior surfaces of the sacral with a horizontal line. 'Measure Cobb's Angle Tool' of 'INFINITT PACS' was used to measure both angles. Lumbar lordotic angle and Ferguson's angle were subdivided into five sections. The number of days from onset and the duration of hospitalization were analyzed in each section. Results Severe hypolordotic lumbar lordotic angle group were found to have longer medical history and hospitalization duration than the control group. The ratio of long-term hospitalization (over 15 days) and chronic medical history (over 180 days) of patients with severe hypolordotic Ferguson's angle were significantly higher than the control group. The ratio of patients with chronic medical history (over 180 days) was significantly higher in severe hyperlordotic Ferguson's angle group than the control group. Conclusions Severe hypolordotic lumbar lordotic angle was related to patient's prognosis. Both severe hyperlordotic and severe hypolordotic Ferguson's angle were found to be related to patient's prognosis. However, a moderate loss of lumbar lordotic angle and Ferguson's angle was not related to prognosis of low back pain patients.

• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.581-595
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• 2001

In performing implant procedures in the anterior portion of the maxilla, many difficulties exist because of anatomical reasons, such as the proximity of the nasal floor, lateral extension of the incisive canal, and labial concavity. On the other hand, in the posterior region of the maxilla, there is often insufficient recipient bone between the maxillary sinus and alveolar ridge due to alveolar ridge resorption and pneumatization of the maxillary sinus. In order to perform implants in such regions, ridge augmentation procedures such as onlay bone graft, guided bone regeneration, and maxillary sinus grafting are performed. In studies of Caucasians, use of autograft from mandibular symphysis has been reported to be highly successful in maxillary sinus grafting. However, in a clinical study of Koreans, autograft of mandibular symphysis has been reported to have significantly low success rate. It has been hypothesized that this is because of insufficient cancellous bone due to thick cortical bone. In order to test this hypothesis, bone quality and morphology of Koreans can be compared with those of Caucasians. In this study, the bone density and morphology of the cortical bone and cancellous bone in the mandibular symphysis of 35 Korean cadavers were evaluated. The following results were obtained: 1. In terms of bone density, type I, type II, and type III consisted of 1.4%(3/213), 72.3%(154/213), and 26.3%(56/213) of the cross-sectioned specimens, respectively. In general, the bone density tended to change from type II to type III, as cross-sectioned specimens were evaluated from the midline to the canine. Type IV wasn't observed in this study. 2. The distance between the root apex and the lower border of the cancellous bone was 18.34mm-20.59mm. Considering that the bone has to be cut 5mm below the root apex during the procedure, autografts with about 15mm of vertical thickness can be obtained. 3. The thickness of cortical bone on the labial side increased from the root apex to the lower border of the mandible. The average values ranged from 1.43mm to 2.36mm. 4. The labio-lingual thickness of cancellous bone ranged from 3.43mm to 6.51mm. The thickness tended to increase from the apex to the lower border of the mandible and decrease around the lower border of cancellous bone. From the above results, the anatomic factors of the mandibular symphysis (bone density, thickness, quantity and length of the cortical bone and cancellous bone) didn't show any difference from Caucasians, and it cannot be viewed as the cause of failure in autografts in the maxillary sinus for implants.