• Title/Summary/Keyword: linear stability

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Clinical Nutrition Services of a Long-term Care Hospital in Korea (전국 요양병원에서의 임상영양서비스 실태 조사)

  • Um, Mi Hyang;Lyu, Eun Soon;Lee, Song Mi;Lee, Seung Min;Lee, Eun;Cha, Jin A;Park, Mi Sun;Lee, Ho Sun;Rha, Mi Yong;Park, Yoo Kyoung
    • Korean Journal of Community Nutrition
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    • v.20 no.3
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    • pp.220-235
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    • 2015
  • Objectives: The purpose of this study was to investigate how clinical nutrition services is provided at a long term care hospital in Korea and to investigate job satisfaction levels of the clinical dietitians. Methods: Survey questionnaire was sent to dietitians working at a long term care hospital in Korea. The participating hospitals (n=240) were randomly selected from 1,180 long- term care hospitals using a stratified sampling method. A total of 134 long term care hospital s and 223 dietitians completed the survey of clinical nutrition service s and job satisfaction questionnaires The job satisfaction questionnaire included 27 job satisfaction questions on task, stability vision, working conditions, and relationship areas. Results: The average nutritional screening rate was 17.9% and the rate of computerized nutritional screening system was 9.7% in the participating hospitals. Nutritional intervention rate was only 3.2% of all patients. KOIHA (Korea Institute for Healthcare Accreditation) accreditated hospitals showed only 50% performance rate of nutrition service evaluation area. This shows that after achieving KOIHA accredition, many hospitals do not emphasize the performance of nutritional services. The job satisfaction scores in all four areas ranged from 2/5 to 3/5, implying generally low job satisfaction level in hospital dietitians. Linear regression analysis results showed that the "hospital adequacy grade" type was a significant predictor of job satisfaction level for two areas (working conditions & relationship). Conclusions: There is a need to provide proper standardized clinical nutrition services as a primary treatment and we observed large variations in the quality of nutritional service s in long term care hospitals. Therefore, government and local hospitals have to work on implementing nutritional programs and policies for improved service and care.

Design of Unsupported Rock Pillars in a Room-and-Pillar Underground Structure by the Tributary Area Method and the Pillar Strength Estimation (지류론과 암주 강도의 추정에 의한 주방식 지하구조의 무지보 암주 설계)

  • Chang, Soo-Ho;Lee, Chulho;Choi, Soon-Wook;Hur, Jinsuk;Hwang, Jedon
    • Tunnel and Underground Space
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    • v.24 no.5
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    • pp.335-343
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    • 2014
  • Room-and-pillar mining method is one of the most popular underground mining method in the world. If the room-and-pillar mining method is able to be adopted in civil works, it would be highly probable to reduce underground construction costs and to expand a underground structure in use. Therefore, this study aims to analyze the design procedure of unsupported rock pillars which are indispensable to ensure the stability of a room-and-pillar underground structure. Parametric studies on their key design parameters are also carried out for 125 different kinds of design conditions. From the study, the width of a rock pillar is found to show a linear relationship with its corresponding safety factor. The safety factor of a unsupported rock pillar decreased drastically like a negative exponential function as the ratio of room width to pillar width increases in the same rock strength condition. Based on the parametric studies, a design chart to simply evaluate the geometric design parameters of a unsupported rock pillar satisfying a design safety factor is also proposed in this study.

Synthesis and Characterization of The Electrolessly Deposited Co(Re,P) Film for Cu Capping Layer (무전해 도금법으로 제조된 Co(Re,P) capping layer제조 및 특성 평가)

  • Han, Won-Kyu;Kim, So-Jin;Ju, Jeong-Woon;Cho, Jin-Ki;Kim, Jae-Hong;Yeom, Seung-Jin;Kwak, Noh-Jung;Kim, Jin-Woong;Kang, Sung-Goon
    • Korean Journal of Materials Research
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    • v.19 no.2
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    • pp.61-67
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    • 2009
  • Electrolessly deposited Co (Re,P) was investigated as a possible capping layer for Cu wires. 50 nm Co (Re,P) films were deposited on Cu/Ti-coated silicon wafers which acted as a catalytic seed and an adhesion layer, respectively. To obtain the optimized bath composition, electroless deposition was studied through an electrochemical approach via a linear sweep voltammetry analysis. The results of using this method showed that the best deposition conditions were a $CoSO_4$ concentration of 0.082 mol/l, a solution pH of 9, a $KReO_4$ concentration of 0.0003 mol/l and sodium hypophosphite concentration of 0.1 mol/L at $80^{\circ}C$. The thermal stability of the Co (Re,P) layer as a barrier preventing Cu was evaluated using Auger electron spectroscopy and a Scanning calorimeter. The measurement results showed that Re impurities stabilized the h.c.p. phase up to $550^{\circ}C$ and that the Co (Re,P) film efficiently blocked Cu diffusion under an annealing temperature of $400^{\circ}C$ for 1hr. The good barrier properties that were observed can be explained by the nano-sized grains along with the blocking effect of the impurities at the fast diffusion path of the grain boundaries. The transformation temperature from the amorphous to crystal structure is increased by doping the Re.

Reliability Analyses of Breakwater Armor Blocks of Harbors in Korea (국내 항만의 방파제 피복 블록의 신뢰성 해석)

  • Kim, Seung-Woo;Suh, Kyung-Duck;Lee, Cheol-Eung;Park, Dong-Heon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.21 no.1
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    • pp.15-29
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    • 2009
  • Most breakwater armor blocks are designed by using Hudson's or van der Meer's formula. The minimum weight of armor blocks is calculated by equating the resistance to the load in each formula. The larger value is then chosen as the design weight. In this study, we have performed reliability analyses for thus designed breakwater armor blocks of 12 trade harbors and 8 coastal harbors in Korea. The probability of failure calculated by the reliability analysis provides a criterion for evaluating the stability of armor blocks. The calculated probability of failure was almost same for all the breakwaters so that we were able to quantitatively evaluate the safety level of armor blocks of existing breakwaters. We also found that the safety factor used in the deterministic design method and the probability of failure in the reliability design method show a linear relationship. Therefore the probability of failure of existing breakwaters can be quantitatively calculated from the safety factors. The calculated probability of failure could also be used for determining the target probability of failure in the future.

An Effect of Uplift Pressure Applied to Concrete Gravity Dam on the Stress Intensity Factor (중력식 콘크리트 댐에 작용하는 양압력이 응력확대계수에 미치는 영향)

  • Lee Young-Ho;Jang Hee-Suk;Kim Tae-Wan;Jin Chi-Sub
    • Journal of the Korea Concrete Institute
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    • v.16 no.6 s.84
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    • pp.841-850
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    • 2004
  • The modeling of uplift pressure within dam, on the foundation on which it was constructed, and on the interface between the dam and foundation is a critical aspect in the analysis of concrete gravity dams, i.e. crack stability in concrete dam can correctly be predicted when uplift pressures are accurately modelled. Current models consider a uniform uplift distribution, but recent experimental results show that it varies along the crack faces and the procedures for modeling uplift pressures are well established for the traditional hand-calculation methods, but this is not the case for finite element (FE) analysis. In large structures, such as dams, because of smaller size of the fracture process zone with respect to the structure size, limited errors should occur under the assumptions of linear elastic fracture mechanics (LEFM). In this paper, the fracture behaviour of concrete gravity dams mainly subjected to uplift Pressure at the crack face was studied. Triangular type, trapezoidal type and parabolic type distribution of the uplift pressure including uniform type were considered in case of evaluating stress intensity factor by surface integral method. The effects of body forces, overtopping pressures are also considered and a parametric study of gravity dams under the assumption of LEFM is performed.

A Comparison of the Difference in the Golf Swing Motion According to Somatotypes (체형에 따른 골프 스윙 동작 비교)

  • Chung, Nam-Ju;Yoon, Hee-Joong;Baik, Young-Soo
    • Korean Journal of Applied Biomechanics
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    • v.12 no.2
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    • pp.33-49
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    • 2002
  • This study was intended to provide basic materials for golf coaching by somatotype by analyzing and comparing the kinematic factors found in each somatotype at the time of golf swing. For this purpose, the somatotype was divided into endomorph, mesomorph and ectomorph in reference to the weight, height and upper arm circumference of each of nine professional golfers. Each of their swing motions was videotaped with the camcorder and their swing motion was analyzed by dividing it into 8 sections. The time required for the swing motion, the displacement of the center of the human body and the rotation angle of the upper body were calculated through the three-dimensional image analysis based on the DLT(Direct Linear Transformation). Based on the findings of this study, the following conclusion was drawn: The endomorphic golfers showed the longest required golf swing time, followed by the mesomorphic golfer and then the endomorphic golfer. The displacement of left-to-right movement was largest in the mesomorphic golfers, followed by the endomorphic golfers the up-to-down displacement was upward at the time of impact and that the endomorphic and mesomorphic golfers raised the sense of stability by maintaining an almost uniform height at the time of impact. As for the rotational angle of the upper body and the rotational angle of the thigh, the upper body and the thigh took a form of rotating earlier in the ectomorphic golfers at the time of impact, who showed a somewhat different characteristics compared to the endomorphic and mesomorphic golfers. It is necessary to investigate the movement of more fundamental forces in presenting the theory related to the kinematic characteristics of this swing by somatotype. Accordingly, it is thought that it is necessary to analyze the center of pressure(COP) using the ground counterforce in the future study.

ADVANTAGES OF USING ARTIFICIAL NEURAL NETWORKS CALIBRATION TECHNIQUES TO NEAR-INFRARED AGRICULTURAL DATA

  • Buchmann, Nils-Bo;Ian A.Cowe
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1032-1032
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    • 2001
  • Artificial Neural Network (ANN) calibration techniques have been used commercially for agricultural applications since the mid-nineties. Global models, based on transmission data from 850 to 1050 nm, are used routinely to measure protein and moisture in wheat and barley and also moisture in triticale, rye, and oats. These models are currently used commercially in approx. 15 countries throughout the world. Results concerning earlier European ANN models are being published elsewhere. Some of the findings from that study will be discussed here. ANN models have also been developed for coarsely ground samples of compound feed and feed ingredients, again measured in transmission mode from 850 to 1050 nm. The performance of models for pig- and poultry feed will be discussed briefly. These models were developed from a very large data set (more than 20,000 records), and cover a very broad range of finished products. The prediction curves are linear over the entire range for protein, fat moisture, fibre, and starch (measured only on poultry feed), and accuracy is in line with the performance of smaller models based on Partial Least Squares (PLS). A simple bias adjustment is sufficient for calibration transfer across instruments. Recently, we have investigated the possible use of ANN for a different type of NIR spectrometer, based on reflectance data from 1100 to 2500 nm. In one study, based on data for protein, fat, and moisture measured on unground compound feed samples, dedicated ANN models for specific product classes (cattle feed, pig feed, broiler feed, and layers feed) gave moderately better Standard Errors of Prediction (SEP) compared to modified PLS (MPLS). However, if the four product classes were combined into one general calibration model, the performance of the ANN model deteriorated only slightly compared to the class-specific models, while the SEP values for the MPLS predictions doubled. Brix value in molasses is a measure of sugar content. Even with a huge dataset, PLS models were not sufficiently accurate for commercial use. In contrast an ANN model based on the same data improved the accuracy considerably and straightened out non-linearity in the prediction plot. The work of Mr. David Funk (GIPSA, U. S. Department of Agriculture) who has studied the influence of various types of spectral distortions on ANN- and PLS models, thereby providing comparative information on the robustness of these models towards instrument differences, will be discussed. This study was based on data from different classes of North American wheat measured in transmission from 850 to 1050 nm. The distortions studied included the effect of absorbance offset pathlength variation, presence of stray light bandwidth, and wavelength stretch and offset (either individually or combined). It was shown that a global ANN model was much less sensitive to most perturbations than class-specific GIPSA PLS calibrations. It is concluded that ANN models based on large data sets offer substantial advantages over PLS models with respect to accuracy, range of materials that can be handled by a single calibration, stability, transferability, and sensitivity to perturbations.

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Analysis of Short-Term and Long-Term Characteristics of GPS Satellite Clock Offsets (GPS 위성시계오차의 장단기 특성 분석)

  • Son, Eun-Seong;Park, Kwan-Dong;Kim, Kyeong-Hui
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.28 no.6
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    • pp.563-571
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    • 2010
  • The GPS satellite has three or four atomic clocks that consist of cesiums and rubidiums and the NANU messages can be used to identify the kind of the onboard atomic clock because they classify the clock type on a daily basis. In this study, for long-term analysis of the GPS satellite clock behavior, we extracted satellite clock errors for every PRN from years 2001 through 2009 using the SP3 files that are provided by the IGS. As a result, the cesium clock offsets usually have a linear trend of drifting. On the other hand, rubidium offsets show curvilinear variations in general, even though they cannot be represented as anyone specific polynomial function. For short-term analysis, we extracted satellite clock errors for each PRN for a week-long period using the CLK files that are also provided by the IGS and curve-fitted them with first-order and second-order polynomial functions. In cases of cesium clock errors, they were well-represented by first-order polynomial functions and rubidium clock errors were similar with second-order polynomials. However, some of rubidium clock errors could not be represented as any polynomial fitting function. To analyze the characteristic of GPS satellite by each block and atomic clock, we applied Modified Allan Deviation criterion to the dataset from years 2007 and 2010. We found that the Modified Allan Deviation characteristics changed significantly according the block and atomic clock type.

Analysis of Buckling Causes and Establishment of Reinforcement Method for Support of Plate Girder Bridge (플레이트 거더교 지점부의 좌굴발생 원인분석 및 보강방안 수립)

  • Ok, Jae-Ho;Yhim, Sung-Soon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.11
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    • pp.520-526
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    • 2019
  • I-type girders are widely applied as very economical sections in plate girder bridges. There has been research on developing composite laminated panels, curved plates reinforced with closed-end ribs, and new forms of ribs and compression flanges for steel box girders. However, there is a limitation in analyzing the exact cause of local buckling caused by an I-type girder's webs. Therefore, an I-type girder's web was modeled using the finite element analysis program LUSAS 17.0 before and after reinforcement. We checked for the minimum thickness criteria presented in the Korea highway bridge design code, and the cause of buckling after performing a linear elastic buckling analysis of dead and live loads was analyzed. Before reinforcement, an eigenvalue (λ1) at the 1st mode was 0.7025, the critical buckling load was smaller than the applied load, and there is a buckling. After reinforcement, when applying vertical and horizontal stiffeners to the web part of the girder at support, a Nodal line was formed, the eigenvalue was 1.5272, and buckling stability was secured. To improve buckling trace of the girder at the support, an additional plate was applied to the web at the support to ensure visual and structural safety, but buckling occurs at center of web. The eigenvalue (λ1) was 3.5299, and this method is efficient for reinforcing the web of the support.

A Study of Meshless Method Programming (무요소법 프로그래밍에 관한 연구)

  • 김학수;배동명
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.38 no.2
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    • pp.110-118
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    • 2002
  • The element free Galerkin method has been suggested by Belyschko, etc. it is applied for linear elastic analysis of solid problems and its convergence characteristics and stability are shown according to the weight function, influence domain and scattered points. The various numerical examples are performed to check the efficiency of 1D EFG and 2D EFG program by changing factors. As a result it have the best results when it used the cubic spline weight function and the scaling parameter d$_{max}$=2. These programs were developed by mixed language programming method using Visual Basic and the C language. so it is fast and efficient. and visually shown the result.t.