• Korean Journal of Materials Research
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• v.34 no.2
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• pp.105-110
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• 2024

Scanning probe microscopy (SPM) has become an indispensable tool in efforts to develop the next generation of nanoelectronic devices, given its achievable nanometer spatial resolution and highly versatile ability to measure a variety of properties. Recently a new scanning probe microscope was developed to overcome the tip degradation problem of the classic SPM. The main advantage of this new method, called Reverse tip sample (RTS) SPM, is that a single tip can be replaced by a chip containing hundreds to thousands of tips. Generally for use in RTS SPM, pyramid-shaped diamond tips are made by molding on a silicon substrate. Combining RTS SPM with Scanning spreading resistance microscopy (SSRM) using the diamond tip offers the potential to perform 3D profiling of semiconductor materials. However, damage frequently occurs to the completed tips because of the complex manufacturing process. In this work, we design, fabricate, and evaluate an RTS tip chip prototype to simplify the complex manufacturing process, prevent tip damage, and shorten manufacturing time.

• International Journal of Knowledge Content Development & Technology
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• v.14 no.2
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• pp.65-80
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• 2024

This paper aims to determine the impact of knowledge creation and sharing on use by librarians in federal universities in Nigeria. The study adopted the survey method of the correlation type, where 518 librarians were surveyed through a close-ended questionnaire, descriptive statistics, Pearson Product Moment Correlation coefficient and multiple regression were used to test the hypotheses. Findings indicate that significant relationships exist between knowledge creation and knowledge sharing (r=0.52), knowledge sharing and knowledge use (r=0.63) and knowledge creation and knowledge use (r=0.52), respectively. Knowledge created and shared by the librarians is used for better work performance. The paper adds value to the existing body of knowledge by proposing the need to understand the importance of knowledge creation and sharing as facilitators of knowledge use by librarians. This will, in turn, enhance service delivery to library patrons, thereby improving library patronage. This paper is limited to knowledge creation and sharing and its impact on knowledge use. Types of knowledge created and channels through which knowledge is shared are outside the focus of this article.

• Research in Community and Public Health Nursing
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• v.4 no.2
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• pp.170-187
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• 1993

The natural growth rate of the Korean population has decreased from 3.0% in 1960 to 1.0% in 1990. This was done with family planning program which was introduced by the government in 1961. The family planning program focused on birth control rather than the characteristics of the individuals and motivations of contraception. People were simply forced to use the method. Whereas, Natural Contraceptive is a method of family planning based solely on the timing of intercourse with the naturally occurring' physiological manifestation of fertilization and in fertilization during the menstrual cycle. This is the combination of self fertility awareness with periodic abstinence. Natural family .planning(NFP) programs in Korea were first started in the Chun-Chen diocese of catholic church by Bishop Thomas Stewart in 1970 In 1975, the Bishops conference launched the Korea Happy Family Movement in the Catholic Hospital Association, to promote the natural family planning. An average of 70,000 people, including adolescents, college students, unmarried and married persons, arid the clergies were trained during a six-year period (1986-1991). 61.5%(24,542 people) of those who completed 3 cycles during 6 year period (1986-1991) became autonomous users and the range was from 48.1% to 78.2%. In 1986, 22.7% of NFP individuals who drooped out of the program because of the desire for conception (23.4%), the difficulty of the method used(25.8%), and the loss of interest(22.8%). During the six-year period the unplanned pregnancy rate at the NFP was 2.9%. The range of the pregnancy rate was at 1.2-9.8%. The rate was decreased as years passed. The major reason for the failure of contraceptive was error by the individuals(61.1%). The percentage of the success of conception was 18.1% of 2.979 for achieving pregnancy. The highest percentage was 58.2% (99 users) in Kwang-Joo diocese and next was 37.1% (10 users) in Chong Joo diocese.

• Wind and Structures
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• v.31 no.2
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• pp.85-102
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• 2020

Accurate load evaluation is essential in any performance-based design. Design wind speeds and associated wind loads are well defined for synoptic boundary layer winds but not for thunderstorms. The method presented in the current study represents a new approach to obtain design wind speeds associated with thunderstorms and their gust fronts using historical data and Monte Carlo simulations. The method consists of the following steps (i) developing a numerical model for thunderstorm downdrafts (i.e. downbursts) to account for storm translation and outflow dissipation, (ii) utilizing the model to characterize previous events and (iii) extrapolating the limited wind speed data to cover life-span of structures. The numerical model relies on a previously generated CFD wind field, which is validated using six documented thunderstorm events. The model suggests that 10 parameters are required to describe the characteristics of an event. The model is then utilized to analyze wind records obtained at Lubbock Preston Smith International Airport (KLBB) meteorological station to identify the thunderstorm parameters for this location, obtain their probability distributions, and utilized in the Monte Carlo simulation of thunderstorm gust front events for many thousands of years for the purpose of estimating design wind speeds. The analysis suggests a potential underestimation of design wind speeds when neglecting thunderstorm gust fronts, which is common practice in analyzing historical wind records. When compared to the design wind speed for a 700-year MRI in ASCE 7-10 and ASCE 7-16, the estimated wind speeds from the simulation were 10% and 11.5% higher, respectively.

• Archives of Plastic Surgery
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• v.45 no.2
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• pp.146-151
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• 2018

Background A persistent problem in autologous breast reconstruction in skin-sparing mastectomies is skin restoration after skin necrosis or secondary oncological resection. As a solution to facilitate reconstruction, skin banking of free-flap skin has been proposed in cases where the overlying skin envelope must be resected, as this technique spares the patient an additional donor site. Herein, we present the largest series to date in which this method was used. We investigated its safety and the possibility of skin banking for prolonged periods of time. Methods All skin-sparing mastectomies and immediate autologous breast reconstructions from December 2009 until June 2013 at our institution were analysed. Results We identified 31 patients who underwent 33 free flap reconstructions in which skin banking was performed. Our median skin banking period was 7 days, with a maximum duration of 171 days. In 22.5% of cases, the banked skin was used to reconstruct overlying skin defects, and in 9.6% of cases to reconstruct the nipple-areolar complex. Microbiological and histological investigations of the banked skin revealed neither clinical infections nor malignancies. Conclusions In situ skin banking, even for prolonged periods of time, is a safe and cost-effective method to ensure that skin defects due to necrosis or secondary oncological resection can be easily reconstructed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.4
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• pp.113-119
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• 1991

In the present study, a methodology has been established for water budget analysis of a river basin for which monthyl rainfall and evaporation data are the only available hydrologic data. The monthly rainfall data were first converted into monthyl runoff data by an empirical formula from which long-term runoff data were generated by a stochastic generation mothod. Thomas-Fiering model. Based on the generated long-term data low flow frequency analysis was made for each of the oberved and generated data set, the low flow series of each data set being taken as the water supply for budget analysis. The water demands for various water utilization were projected according to the standard method and the net water consumption computed there of. With the runoff series of the driest year of each generated data set as an input water budget computation was made through the composite reservoirs comprised of small reserviors existing in the basin by deficit-supply method. The water deficit computed through the reservior operation study showed that the deficit radically increases as the return period of low flow becomes large. This indicates that the long-term runoff data generated by stochastic model are a necessity for a reliable water shortage forecasting to cope with the long-term water resourse planning of a river basin. F.E.M. program (ADINA) is also presented herein.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1082-1082
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• 2001

Extrusion is one of the most important processes in polymer industry. The characterization of the polymer melt during processing will improve this process noticeably, One possibility of characterizing the actual processed polymer melt is the inline near infrared (NIR) spectroscopy, With this method several polymer properties can be observed during processing, e.g. composition, moisture ormechanical properties of the melt. For this purpose probes for transmission and reflection measurements have been developed, withstanding the high temperatures and pressures appearing during extrusion process (tested up to 300$^{\circ}C$ and 10 ㎫). For the transmission system an optical bypass was developed to eliminate disturbing spectral influences and hence increase the long term stability, which is the prerequisite for an industrial application. Measurements in transmission and reflection produced comparable results (or blending processes, where the prediction error was less than 1%. An optimum RMSEP of only 0.24% was found for preprocessed polymer blends measured in transmission on a laboratory extruder. A transflection measurement allowed for the first time the recording of relevant NIR-spectra in the screw area of an extruder. The application to a (PE+PP) blending process delivered promising results. This new measurement mode allows the observation of the ongoing processes within the screw area, which is of maximum Interest for reactive extrusion processes. Due to economic reasons the calibration transfer between different extrusion systems is also of high importance. Investigations on simulated and real-world spectra showed that a calibration transfer is possible. A new method alternatively to the well-known direct standardization procedures was developed, which is based on an automatic data pretreatment. This procedure delivers comparable results for the calibration transfer. Overall this paper presents concepts, components and algorithms for the inline near infrared (NIR) spectroscopy for polymer extrusion, which allows the use of it in a real industrial extrusion process.

• Safety and Health at Work
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• v.6 no.3
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• pp.159-173
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• 2015

The hand coordinate systems for measuring vibration exposures and biodynamic responses have been standardized, but they are not actually used in many studies. This contradicts the purpose of the standardization. The objectives of this study were to identify the major sources of this problem, and to help define or identify better coordinate systems for the standardization. This study systematically reviewed the principles and definition methods, and evaluated typical hand coordinate systems. This study confirms that, as accelerometers remain the major technology for vibration measurement, it is reasonable to standardize two types of coordinate systems: a tool-based basicentric (BC) system and an anatomically based biodynamic (BD) system. However, these coordinate systems are not well defined in the current standard. Definition of the standard BC system is confusing, and it can be interpreted differently; as a result, it has been inconsistently applied in various standards and studies. The standard hand BD system is defined using the orientation of the third metacarpal bone. It is neither convenient nor defined based on important biological or biodynamic features. This explains why it is rarely used in practice. To resolve these inconsistencies and deficiencies, we proposed a revised method for defining the realistic handle BC system and an alternative method for defining the hand BD system. A fingertip-based BD system for measuring the principal grip force is also proposed based on an important feature of the grip force confirmed in this study.

• Advances in pediatric surgery
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• v.13 no.1
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• pp.23-29
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• 2007

Tapering enteroplasty was first described by Thomas in 1969 as one method of intestinal anastomosis. The advantages of tapering enteroplasty in the intestinal atresia are: First, it makes end-to-end anastomosis possible between the atretic bowel ends with considerable differences in diameters. Second, it promotes the recover of the postoperative bowel function. Third, it prevents the possibility of the short bowel syndrome by eliminating the need of resecting the dilated bowel. A total of 22 patients with intestinal atresia who underwent tapering enteroplasty from January 1988 to December 2005 at our institute were reviewed. In 3 of 22 cases, tapering enteroplasty was the $2^{nd}$ operation after an initial end-to-oblique anastomosis. We reviewed the following items: age, sex, type and location of intestinal atresia, initial feeding and total enteral feeding start day, the length of hospital stay and complications. The average age of the patients was 7 days. Male to female ratio was 1 to 1.2 (10 cases: 12 cases). We performed the tapering enteroplasty on all types and locations of the intestinal atresia from the duodenum to the colon: type I (n=3), type II (n=4), type IIIA (n=7), type IIIB (n=5), type IIIB and IV (n=1), type IV (n=1) and type C (duodenum) and type IIIB and IV (jejunum). On the average, the oral feeds were started on the postoperative $8.8^{th}$ day, and full caloric intake via the enteric route was achieved on postoperative $13.3^{th}$ day. The average length of hospital stay was 19.6 days. There were 1 case (4.5 %) of anastomotic complication and 2 cases (9 %) of adhesive ileus among 22 patients. The tapering enteroplasty on all types of intestinal atresia is a usefull operative method when there are considerable diameter differences between the atretic bowel ends.

• Water for future
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• v.19 no.2
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• pp.149-156
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• 1986

The generated sequences of monthly flows were analyzed based on the range concept. With the optimum operation rule of the reservoirs as the one which maximizes the wateruse downstream the waterrelease from the reservoir was determined and with \ulcorner consideration to the mean inflows and the range of monthly flows the required reservoirs capacity was stochastically determind. It is suggested that the result obtained in this study would be applied to approximately estimate, in the stage of preliminary design, the required capacity of a reservoir in question with the limited information such as the mean monthly inflow and the period of reservoir operation. For the determination of a reservoir capacity Rippl's mass-curve method has been long used with the past river flow data assuming the same flow records will be repeated in the future. This study aims to find out a better method for determining the reservoir capacity by employing the analytical theory based on the stochastic process. For the present study the synthetic generation methods of Thomas-Fiering type was used to synthetically generate 50 years of monthly river inflows to three single-purpose reservoirs and three multi-purpose reservoirs.