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Analyzing Common Method Bias of the Korean Empirical Studies on Technology Acceptance Model (한국 TAM 실증연구의 동일방법편의 분석)

  • Baek, Sang-Yong
    • The Journal of Information Systems
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    • v.21 no.1
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    • pp.1-17
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    • 2012
  • Common Method Bias(CMB) may cause the potential inflation of correlations between measures assessed via the same method. The problem of CMB has been well known in behavioral sciences because the survey method with self-reporting is vulnerable to CMB. Thus, the discussion on CMB is still ongoing in the MIS research in US. However, in Korea, the MIS research has never paid attention on the CMB problem. The purpose of this study is to examine the CMB problem in the Korean MIS research. To evaluate the effect of CMB, empirical studies on Technology Acceptance Model(TAM) are selected because (1) TAM is one of the MIS research areas studied intensively, (2) TAM is a theoretical model well supported by the existing empirical studies so that the result of this study would have a great ripple effect when the CMB problem turned out to be serious, (3) CMB is domain-specific. 47 TAM samples (out of 45 studies) from three Korean Journals were selected and the relevant data were collected such as correlation matrixes and the measures of the dependent variable. To find and evaluate the size of CMB, two analytic methods (Marker-Variable Technique and Method-Method Pair Technique) are employed. The result showed that there exists CMB in the Korean studies but the problem is not so serious to distort the empirical testing, compared with that of US studies. However, considering that CMB can contaminate the testing results, Korean MIS researchers should explicitly deal with the problem in designing empirical studies and collecting data.

The Effects of Preoperative Nursing Instruction on tile Physical and Emotional Recovery of Pediatric Surgical Patients - An Experimental Study- (소아의 수술전 환자교육이 신체 및 정서에 미치는 영향)

  • 심치정
    • Journal of Korean Academy of Nursing
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    • v.4 no.2
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    • pp.44-56
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    • 1974
  • Very few studies regarding the effects of preoperative nursing intervention on children's welfare after surgery have been conducted. The purpose of this study was 1) to evaluate the effects of preoperative nursing instructions on children's physical recovery and emotional state after surgery and 2) to analyse the relationship between the effects of preoperative nursing instructions and the age and general anxiety of child. The study was conducted flow: August 15th to October 30th at Severance Hospital, Seoul, Korea. A total of 41 Pediatric surgical Patients, between the age of 4 to 14, participated in the study. Twenty patients, randomly selected, were visited by the experimenter in the evening before, surgery and received specific preoperative nursing instructions. These instructions were designed to alleviate emotional stress and were adopted to the age of child. The postoperative recovery of these patients were then compared with a randomly selected control group of 21 patients who received only the routine preoperative care by the staff in the hospital Dependent variable were vomiting, pain medication, ability to void, elevation of temperature, infection, the between surgery and hospital discharge and postoperative emotional stress which was measured by the vital signs. Because of the limitation of the sample size it was difficult to obtain valid statistical results. However, the analysis of the raw data indicates that: 1) the preoperative nursing instructions appears to promote physical recovery and it seems especially effective in preventing elevation of temperature and shortening the length of the hospital stay, 2) the preoperative nursing instruction also seems to be effective in relieving the child's emotional stress(situational anxiety) after surgery, 3) the patient's general anxiety level preparatively seems to be a predictor of postoperative problems, 4) the preoperative nursing instructions were an effective means of promoting physical recovery in every age group as long as the child understood the instructions. The above data would seem to indicate that all preoperative pediatric patients four years of age or older, if they can understand, should have preoperative nursing instruction in order to alleviate postoperative stress and enhance physical recovery. The level of general anxiety preparatively deserves special attention since the amount of nursing instruction needed seems to vary with tile level of anxiety.

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Study on the Core Loss Improvement of SiFe Plate in Relation with Laser Pulse Width in the Laser Scribing (레이저 스크라이빙에 있어서 레이저의 펄스폭에 따른 규소강판의 코어손실 개선 연구)

  • Ahn, Seung-Joon;Park, Chul-Geun;Ahn, Seong-Joon
    • Journal of the Korean Magnetics Society
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    • v.15 no.6
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    • pp.320-324
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    • 2005
  • The core loss of $3\%$ SiFe is strongly dependent on silicon content, impurities, permeability, and domain structure of the SiFe. Domain refining has been proved to be very good method for reduction of core loss in high permeability grain oriented SiFe, and laser scribing is well-blown as an effective and industrially important method of domain refinement. In this work, magnetic domain refinement has been carried out by using a pulsed Nd : YAG laser, and the core losses have been measured and analyzed to and optimal parameters of the laser treatment. The laser hem was focused with a spot size of $100{\mu}m$ and pulse energy of 10${\~}$35mJ and the lines were scribed with a period of ${\~}$5mm. The core loss was improved up to $17\%$ with 30 ns-Nd : YAG laser beam in $3\%$ SiFe.

Nanoencapsulations of Paraffin Wax by Miniemulsion Polymerization and Their Thermal Properties as Phase Change Materials (미니에멀젼 중합에 의한 파라핀 왁스의 나노캡슐화 및 상변환물질로서의 열적 특성)

  • Shin, Dae Cheol;Lee, Kyungwoo;Kim, Jeong Soo
    • Polymer(Korea)
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    • v.37 no.1
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    • pp.15-21
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    • 2013
  • Encapsulation of a paraffin wax core as a phase change material with polystyrene shell and the its thermal characteristics caused by the encapsulation were studied. For the nanoencapsulation, the miniemulsion polymerization method was selected. The factors affecting the thermal properties of prepared nanocapsule particles of phase change material were analysed in aspect of the structure of crosslinking agents, amounts of surfactant, ratio of paraffin wax to monomer, and hydrophilicity of initiators. It was assumed that Oswald ripening plays the most important role in the changes of particle size, particle morphology, and thermal capacity of nanocapsule core. It was elucidated that the thermal capacity was also dependent on the hydrophilicity and crosslinking density of polystyrene shell components.

Caspase-3-facilitated Stoichiometric Cleavage of a Large Recombinant Polyprotein (카스파제-3 효소를 이용한 폴리-단백질의 정량적 프로세싱 분석)

  • Kim, Moonil
    • Journal of Life Science
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    • v.25 no.4
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    • pp.385-389
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    • 2015
  • In this study, it is reported that a large polyprotein can be stoichiometrically cleaved by the use of caspase-3-dependent proteolysis. Previously, it has been shown that the proteolytic IETD motif was partially processed when treated with caspase-3, while the DEVD motif was completely cleaved. The cleavage efficiency of the DEVD-based substrate was approximately 2.0 times higher than that of the IETD substrate, in response to caspase-3. Based on this, 3 protein genes of interest were genetically linked to each other by adding two proteolytic cleavage sequences, DEVD and IETD, for caspase-3. Particularly, glutathione-S transferase (GST), maltose binding protein (MBP), and red fluorescent protein (RFP) were chosen as model proteins due to the variation in their size. The expressed polyprotein was purified by immobilized metal ion affinity chromatography (IMAC) via a hexa-histidine tag at the C-terminal end, showing 93 kDa of a chimeric GST:MBP:RFP fusion protein. In response to caspase-3, cleavage products, such as MBP:RFP (68 kDa), MBP (42 kDa), RFP (26 kDa), and GST (25 kDa), were separated from a large precursor GST:MBP:RFP (93 kDa) via SDS-PAGE. The results obtained from this study indicate that a multi-protein can be stoichiometrically produced from a large poly-protein by using proteolytic recognition motifs, such as DEVD and IETD tetra-peptides, for caspase-3.

Foodservices Satisfaction and Food Preference According to the Types and Cooking methods of the Elderly with Dementia in a Geriatric Hospital (요양병원 치매노인의 급식 만족도와 식품의 종류 및 조리법에 따른 선호도 조사)

  • Bae, Mi Ae;Kim, Min Ji;Chang, Kyung Ja
    • Journal of the Korean Society of Food Culture
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    • v.32 no.6
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    • pp.534-548
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    • 2017
  • Elderly with dementia in geriatric hospitals (EDGH) are highly dependent on hospital meals. This study evaluated the foodservices satisfaction and food preference of the EDGH. The survey was conducted on 104 elderly with dementia (21 males and 83 females) in 4 geriatric hospitals in Seoul and Incheon in November, 2016. Data were collected from interviews using a questionnaire that consisted of 6 questions for foodservice satisfaction and 24 questions (10 categories) for food preference. The data were analyzed using SPSS ver. 20.0. The satisfaction with taste, saltiness, texture, and variety in foodservices was good, but the satisfaction with the amount was not, and the reason for leaving food was its large serving size. The subjects preferred soft boiled rice, noodles, porridges, meats, fish, seafood, vegetables, and fruits. Among them, they preferred more janchiguksu, red bean porridge, beef, croaker, oyster, spinach, and banana. Regarding the cooking methods, they preferred soup, grill, and boiling, but not frying. The also preferred Chinese cabbage kimchi, but they did not prefer hard kkakdugi. They did not prefer milk because of diarrhea, but they preferred yogurt. Therefore, to provide a satisfying meal for EDGH, it is necessary to develop a friendly diet considering their food preferences.

Stiffness Modulus Comparison in Trackbed Foundation Soil

  • Kim, Daesung;Cho, Hojin;Park, Jaebeom;Lim, Yujin
    • International Journal of Railway
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    • v.8 no.2
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    • pp.50-54
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    • 2015
  • The primary function of the trackbed in a conventional railway track system is to decrease the stresses in the subgrade to be in an acceptable level. A properly designed trackbed layer performs this task adequately. Many design procedures have used assumed and/or are based on critical stiffness values of the layers obtained mostly in the field to calculate an appropriate thickness of the sublayers of the trackbed foundation. However, those stiffness values do not consider strain levels clearly and precisely in the layers. This study proposes a method of computation of stiffness that can handle with strain level in the layers of the trackbed foundation in order to provide properly selected design values of the stiffness of the layers. The shear modulus values are dependent on shear strain level so that the strain levels generated in the subgrade in the trackbed under wheel loading and below plate of Repeated Plate Bearing Test (RPBT) are investigated by finite element analysis program ABAQUS and PLAXIS programs. The strain levels generated in the subgrade from RPBT are compared to those values from RC (Resonant Column) test after some consideration of strain levels and stress consideration. For comparison of shear modulus G obtained from RC test and stiffness moduli $E_{v2}$ obtained from RPBT in the field, many numbers of mid-size RC tests in laboratory and RPBT in field were performed extensively. It was found in this study that there is a big difference in stiffness modulus when the converted $E_{v2}$ values were compared to those values of RC test. It is verified in this study that it is necessary to use precise and increased loading steps to construct nonlinear curves from RPBT in order to get correct $E_{v2}$ values in proper strain levels.

Characteristics of Sputtered Ta films by Statistical Method (통계적 실험 방법에 의한 Ta 박막의 증착 특성 연구)

  • Seo, Yu-Seok;Park, Dae-Gyu;Jeong, Cheol-Mo;Kim, Sang-Beom;Son, Pyeong-Geun;Lee, Seung-Jin;Kim, Han-Min;Yang, Hong-Seon;Park, Jin-Won
    • Korean Journal of Materials Research
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    • v.11 no.6
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    • pp.492-497
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    • 2001
  • We report the characteristics and the dependence of sputter-deposited Ta films on the process parameters. The properties of as-deposited Ta films such as deposition rate, resistivity, Rs uniformity, reflectivity, and stress were investigated and analyzed as a function of process parameter using a statistical experimental method. The functional relationships between the independent and dependent variables were predicted by surface response. The optimal deposition condition of DC magnetron sputtered Ta films was obtained at the chamber pressure of 2 mTorr, power density of 8 W/$\textrm{cm}^2$, and substrate temperature of 2$0^{\circ}C$ by means of resistivity and Rs uniformity. The fitness value for quadratic model as evaluated by the R- square was 0.85~ 0.9 without pooling. The as-deposited Ta films exhibited the resistivity of ~180$\mu$$\Omega$cm with Rs uniformity of ~2%. The transmission electron microscopy and x-ray diffractometry identified that the phase of as-deposited film was $\beta$-Ta having the grain size of 100~200.

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Reaction between Calcium-doped Lanthanum Chromite and Yttria Stabilized Zirconia (칼슘이 첨가된 란탄-아크롬산 염과 이트리아 안정화 지르코니아 계면간의 반응)

  • Choe, Jin-Sam
    • Korean Journal of Materials Research
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    • v.11 no.6
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    • pp.460-464
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    • 2001
  • The ceramic diffusion coupling with the green body of calcium-doped lanthanum chromite(La$_{0.8}$Ca$_{0.2}$CrO$_3$CLC- G) and sintered calcium-doped lanthanum chromite(La$_{0.8}$Ca$_{0.2}$CrO$_3$ CLC) by Pechini's method on yttria stabilized zirconia(YSZ) plate has been investigated. The X-ray diffraction pattern of CLC sides at the reacted CLC-G/ CLC and CLC/YSZ interface were identified as La$_{1-x}$ Ca$_{x}$CrO$_3$ and the unreacted YSZ side was cubic-ZrO$_2$ at the treated condition, 1300~1500 C for 10 hr in air, respectively. The order of migration components between CLC/YSZ interface was Zr>La>>Cr>>>Ca and these changes were not dependent upon the treated conditions. The grain shape and size at the interface of CLC-G/CLC was appeared to have a uniform distribution with increasing temperature. The bonding reaction of YSZ/CLC was occurred without a large amount change of the compositions in SEM photos.os.otos.os.

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Synthesis and Sintering Behavior of Zr2WP2O12 Ceramics (Zr2WP2O12 세라믹스의 합성과 소결거동 연구)

  • Kim, Yong-Hyeon;Kim, Nam-Ok;Lee, Sang-Jin
    • Journal of the Korean Ceramic Society
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    • v.49 no.6
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    • pp.586-591
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    • 2012
  • $Zr_2WP_2O_{12}$ powder, which has a negative thermal expansion coefficient, was synthesized by a solid-state reaction with $ZrO_2$, $WO_3$ and $NH_4H_2PO_4$ as the starting materials. The synthesis behavior was dependent on the solvent media used in the wet mixing process. The $Zr_2WP_2O_{12}$ powder prepared with a solvent consisting of D. I. water was fully crystallized at $1200^{\circ}C$, showing a sub-micron particle size. According to the results obtained from a thermal analysis, a $ZrP_2O_7$ was synthesized at a low temperature of $310^{\circ}C$, after which it was reacted with $WO_3$ at $1200^{\circ}C$. A new sintering additive, $Al(OH)_3$, was applied for the densification of the $Zr_2WP_2O_{12}$ powders. The cold isostatically pressed samples were densified with 1 wt% $Al(OH)_3$ additive or more at $1200^{\circ}C$ for 4 h. The main densification mechanism was liquid-phase sintering due to the liquid which resulted from the reaction with amorphous or unstable $Al_2O_3$ and $WO_3$. The densified $Zr_2WP_2O_{12}$ ceramics showed a relative density of 90% and a negative thermal expansion coefficient of $-3.4{\times}10^{-6}/^{\circ}C$. When using ${\alpha}-Al_2O_3$ as the sintering agent, densification was not observed at $1200^{\circ}C$.