• Advances in concrete construction
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• v.15 no.1
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• pp.23-39
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• 2023

One of the important problems of concrete placing is the concrete compaction, which can affect the strength, durability and apparent quality of the hardened concrete. Therefore, vibrating operations might be accompanied by much noise and the need for training the involved workers, while inappropriate functioning can result in many problems. One of the most important methods to solve these problems is to utilize self-compacting cementitious composites instead of the normal concrete. Due to their benefits of these new materials, such as high tensile, compressive, and flexural strength, have drawn the researchers' attention to this type of cementitious composite more than ever. In this experimental investigation, six mixing designs were selected as a base to acquire the best mechanical properties. Moreover, forty-eight rectangular composite panels with dimensions of 300 mm × 400 mm and two thickness values of 30 mm and 50 mm were cast and tested to compare the flexural and impact energy absorption. Steel fibers with volume fractions of 0%, 0.5% and 1% and with lengths of 25 mm and 50 mm were imposed in order to prepare the required cement composites. In this research, the composite panels with two thicknesses of 30 mm and 50 mm, classified into 12 different groups, were cast and tested under three-point flexural bending and repeated drop weight impact test, respectively. Also, the examination and comparison of flexural energy absorption with impact energy absorption were one of the other aims of this research. The obtained results showed that the addition of fibers of longer length improved the mechanical properties of specimens. On the other hand, the findings of the flexural and impact test on the self-compacting composite panels indicated a stronger influence of the long-length fibers.

• Journal of Advanced Navigation Technology
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• v.25 no.6
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• pp.530-535
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• 2021

In this paper, the design method for a chipless RFID tag using ELC resonators is proposed. A four-bit chipless RFID tag is designed in a two by two array configuration using three ELC resonators with different resonant peak frequencies and one compact IDC resonator. The resonant peak frequency of the bistatic RCS for the IDC resonator is 3.125 GHz, whereas those of the three ELC resonators are adjusted to be at 4.225 GHz, 4.825 GHz, and 5.240 GHz, respectively, by using the gap between the capacitor-shaped strips in the ELC resonator. The spacing between the resonators is 1 mm. Proposed four-bit tag is fabricated on an RF-301 substrate with dimensions of 50 mm×20 mm and a thickness of 0.8 mm. It is observed from experiment results that the resonant peak frequencies of the fabricated four-bit chipless RFID tag are 3.290 GHz, 4.295 GHz, 4.835 GHz, and 5.230 GHz, respectively, which is similar to the simulation results with errors in the range between -2.3% and 0.2%.

• Korean Journal of Social Welfare
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• v.60 no.2
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• pp.77-98
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• 2008

For women living with mental illness, motherhood may be a normalizing life experiences and offers the opportunity to develop competencies in a major life roles. So, the main premise of this study that social contexts, social support of spouse and extended family, is very important for successful parenting of mothers with mental illness. Thus this study analyzes the impact of marital relationship and social support of networks on three dimensions of parenting competency(expression of love, encouragement of independence, rational discipline) when the socioeconomic(age, number of offsprings, subjective economic level) and disability variables(diagnosis, severity of symptoms, chronicity, frequencies of psychiatric admission) are controlled. This study conducted the survey with 145 mothers with schizophrenia and mood disorder. The major finding of the study are : i) Using step-wise multiple regression, marital relationship, social supports and economic level affect significantly on the expression of love. ii) Using step-wise multiple regression, the most powerful influenced factor on encouragement of independence is marital relationship. iii) Using step-wise multiple regression, diagnosis, severity of symptoms, chronicity and economic level affect significantly on the rational discipline. That is two dimensions of parenting competency, expression of love and encouragement of independence, can be explained well by social contexts variables(marital relationship, social support, economic level). But only rational discipline can be explain well by disability factors. In conclusion, this study recommends service providers to use family based comprehensive case management for the mothers with mental illness.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.2
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• pp.213-218
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• 2010

A cooling system utilizing liquid helium to chill the cryopanel (800 mm $\times$ 700 mm dimensions) down to 4.2 K was designed, implemented, and tested to verify the role of the cryopanel as a heat sink for the payload of a spacecraft inside the large thermal vacuum chamber (effective dimensions : 8 m ($\Phi$) $\times$ 10 m (L)) of KARI (Korea Aerospace Research Institute). Two LHe (Liquid Helium) Dewars, one for the main supply and the other for refilling, were used to supply liquid helium or cold helium gas into this cryopanel, and flow control for the target temperature of the cryopanel within requirements was done through fine adjustment of the pressure inside the LHe Dewars. The return helium gas from the cryopanel was reused as a thermal barrier to minimize the heat influx on the core liquid helium supply pipe. The test verified a cooling time of around three hours from the ambient temperature to 40 K (combined standard uncertainty of 194 mK), the capacity for maintaining the cryopanel at intermediate temperatures, and a 1 K uniformity over the entire cryopanel surface at around 40 K with 20 W cooling power.

• Management & Information Systems Review
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• v.30 no.2
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• pp.57-79
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• 2011

One of the fastest growing sector in tourism industry is MICE industry due to globalization among the countries in various parts including business, politics, and cultural exchange. The objectives of this research can be in two fold: firstly, to evaluate the convention service quality and categorize them into three groups, basic service, performance service and exciting service; secondly, to provide the exciting service as a recovery program to restore customer satisfaction and their intention to reuse when the basic or performance service failure occurs. The results are as follows: among the four dimensions of the service quality, only the availability of information and the employee's performance were effected by the exciting service quality. Secondly, employees's performance can only be effected by the exciting service when customer service factor is included prior to the events. Thirdly, the following dimensions of services were not selected to be effective by the exciting services: conditions of physical facility, related infra-structure, the process of customer service and the program. Fourthly, only the additional services and events were selected to be the effective exciting services for the recovery program.

• Journal of the Ergonomics Society of Korea
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• v.36 no.2
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• pp.123-144
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• 2017

Objective: The objective of this study is to evaluate affection on how users perceive colors viewed from an automotive visual display according to cultural and radical differences including North America, Europe, and Southeast Asia. This study especially aims to identify effects of the variation of tone and chroma of representative color groups by analyzing affection differences depending on cultural and racial differences targeting the colors constituted through variation of tone and chroma, centered on representative colors. Background: The colors of the menu, information display or background viewed through an automotive visual display are an important factor stimulating consumer's affection, and therefore an effort to express the vehicle's brand and product image through colors is made. The studies on colors focus only on the research on unique characteristics of colors, but an affective approach lacks according to cultural and racial differences on colors considering tone and chroma variation within a color from the currently used automotive visual displays. Method: To grasp the visual affection felt by users, this study extracted affective adjectives related with colors through existing literature and a dictionary for adjectives, and presented human affection dimensions on colors through evaluation of various colors. Prior to carrying out affection evaluation, the basic light sources, red (R), green (G), and blue (B) constituting the colors used for automotive visual displays were defined as a representative color group, respectively. When colors in a color group are constituted, the evaluation target of each color group consisted of the colors considering the variation of tone and chroma by changing color sense through RGB values of the remaining two light sources. And then, this study carried out affection evaluation on the constituted colors targeting the subjects with cultural and racial differences. Results: As a result of evaluating the constituted colors with representative affections, there were statistically significant differences between the groups having cultural and racial differences. As a result of S-N-K post-hoc analysis on the colors showing significant differences, North America and Europe were classified as heterogeneous groups. In some cases, Korea was classified as the homogeneous group with North America, but Korea was mainly classified as the homogenous group with Europe. Conclusion: The representative affections on colors from an automotive visual display was drawn as three affective dimensions: passionate, neat, and masculine. Based on these, the affection of Korea and Europe on the constituted colors showed significant differences from that of North America, as a result of affection evaluation on the constituted colors viewed through the visual display by reflecting cultural and racial factors. Regarding representative color groups, bigger cultural and racial differences were revealed in terms of affection on red and green colors than on blue color, and variation of affection was the biggest in the red color. Application: This study analyzed correlations of affection considering the colors constituted through variation of tone and chroma, and the culture and race in the representative color groups constituting a visual display. The results of this study are predicted to be utilized in coordination and selection of colors viewed from an automotive visual display taking into account culture and race.

• Journal of Korean Academy of Nursing
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• v.28 no.2
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• pp.441-456
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• 1998

The purpose of this study was to develop a reliable and valid instrument to measure hope for cancer patients in Korea. This Hope Scale(Kim & Lee Hope Scale ; KLHS ) was developed based on not only critical universal attributes explaining both basic hope (generalized hope) and specific hope but also particular characteristics varing from culture and situation, which were revealed in a comprehensive review of the literature. Initially 60 items were generated from three sources : 36 items from the Q-sample used in the Kim's study, 1992, 21 representative items(statements) from the rest Q-population of the above study, 3 items related to the newly discovered category in the new qualitative study using 10 open ended question(death and dying) from the new qualitative study on the 20 cancer patients. At first 3 items were eliminated by the critique of the content validity experts, who were high experienced nurse, nursing professors. And then 4 items were eliminated in consideration of corrected item total correlation coefficiency, theoretical framework of this study. After that, 14 items were eliminated in comparing two or three items identified with the same meaning in each factor by this research team with factor loading and communality. This Hope Scale was finally constructed with 39 items. Psychometric evaluation was done on 492 adults(104 cancer patients, 388 adults who imagined who were cancer patients ranging from 18 to 76 years old. The results revealed high internal consistency Alpha coefficiency of .9351. Princial Component Factor Analysis with Varimax Rotation resulted in 8 factors with more than 1.0 of Eigenvalue. Referring to Eigenvalues, percent of variances(>60%), reproduced correlation matrix, and our theoretical framework, we decided the eight factors were the best1 solution to represent hope dimensions sufficiently. The eight factors were "confidence in possibility of cure", "sense of internal satisfaction", "being in communion", "meaning of life", "Korean hope perspectives", "belief in god", "self confidence", "self-worth". Among these factors, "confidence in possibility of cure", "sense of internal satisfaction", "Korean hope perspectives" were identified as different hope dimensions from those of Nowotny Hope Scale and Herth Hope Scale. There was significant negative correlation of r=-.4736 between this hope scale and Beck Hopelessness Scale (BHS), and significant positive correlation of r=.3685 between this hope scale and Life Orientation Test (LOT) which indicate convergent and discriminant validity. The range of hope scores was from 71 to 244, with a mean of 171.97(SD=28.16).

• Journal of Korean Academy of Nursing
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• v.30 no.6
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• pp.1543-1555
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• 2000

Home health care is moving into a set of new realities. An era of competition and cost containment has arrived. Before nurses are able to contain costs or describe the relationship between nursing activities, cost must be accurately measured based on the nurse's workload. Nurses in home health care usually desire to measure expenses for one of three reasons : reimbursement, management, or research. The purpose of the study was to investigate the work input by Registered Nurse in each of the home health care activities by relative value units and identify the factors affecting the nurses' total work input in health care services. To measure the work input by nurses, work was defined by four dimensions: time, physical effort, mental effort, and stress. This study used a descriptive-correlational design. Data collection consisted of two phases. In phase I, data on home health activities performed by nurses were collected. In phase II, data on nurses' time, physical effort, mental effort, and stress in each of home health care activities discovered phase I were collected. In this method, the respondent was asked to rate a service in relation to a reference service using a ratio scale. The sample included 39 home health care nurses. The results of the study indicated that home health care activities performed by the nurses were in 10 categories and 69 items. Measuring the relative work inputs in each of home health care activities, and foley catheterization was selected as the reference to service. In terms of time and physical effort dimensions, full bath service was rated as the most strenuous among 69 activities by the respondents, and intramuscular injection was rated as least. It was found that emergency treatment required the highest mental effort and the highest stress, while blood sugar tests required the lowest mental effort. Approximately 91.3% of the variance in total work input was accounted for by the linear combination of time, physical effort, mental effort judgement, and stress. Examining the regression coefficients of those variables, physical effort, time, and stress were found as the predictors which were significantly associated with the total work of nurses in home health care. Professional nursing's next step in the conundrum of economic volatility is to develop a tool to reflect the interaction of functional deficiency and direct professional nursing care. And this will be a more accurate predictor of nursing resource use and ultimately a great forcaeter cost.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.3
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• pp.311-322
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• 2014

This study was conducted to assess the impact of work-related musculoskeletal disorders (WMSDs) on health related quality of life (QoL) in the firefighter under the recent IT environment. The data were collected by face to face interview using a structured questionnaire in the 366 respondents. WMSDs symptoms were measured by a self-assessed questionnaire on symptom table of NIOSH and health-related QoL was measured by SF-36. The prevalence of WMSDs was 38.0% in upper limbs, 35.5% in the low back, 21.6% in lower limbs, and 59.3% in two or more parts of the body. Subjects with symptoms of WMSDs had significantly lower scores in 7 dimensions of QoL except 'emotional role limitation' than those without symptoms of WMSDs at the area of upper extremities (neck, shoulder, arm/wrist, and hand/wrist/fingers). On the other hand, subjects with symptoms of WMSDs had significantly lower scores on all QoL dimensions than those without symptoms of WMSDs at the area of lower back or lower extremities. These results suggest that WMSDs had a negative effect on QoL. Therefore, prevention of WMSDs should be considered intervention strategies for improvement of QoL, especially in firefighters.

• Management & Information Systems Review
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• v.28 no.4
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• pp.45-66
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• 2009

This research investigates the systematic relation between corporate governance and corporate social responsibility(CSR). Based on the argument that corporate governance would play the role of mitigating conflicts between firms and society, we hypothesized that corporate governance would enhance CSR performance. Specifically, the firms with good governance are predicted to have CSR performance than those with bad governance. These hypotheses were tested using 130ce rean firms from 1998 to 2005. An index published by e rean Economic Justice mance the(KEJm) was used as the measureses wSR performance. Our empirical results suggest that the firms with good governance as measured by f reign investh bad goothshae directh bad goirdit committee exhibit better CSR performance. The primary purposeses this s tdy is to identify the determinants es the use b' satissaction and commitment in pe bn thomedia. For these purposes, we developegoi research modehobased on the literaturesreviews es pe bn tho media, pe ceived risk and interactivity, satissaction, and commitment. This study has identified four dimensions in the concept of perceived risk, such as privacy risk, social risk, time loss risk, and economic risk, and three dimensions in the concept of perceived interactivity, such as active control, two-way communication, and responsiveness.