Liveness Detection of Fingerprints using Perspiration Patterns in Various Environments

Heeseung Choi,Kyoungtaek Choi,Jaihie Kim 대한전자공학회 2005 ITC-CSCC :International Technical Conference on Ci Vol.2005 No.4

Fingerprint Matching Incorporating Ridge Features With Minutiae

Heeseung Choi,Kyoungtaek Choi,Jaihie Kim IEEE 2011 IEEE transactions on information forensics and sec Vol.6 No.2

<P>This paper introduces a novel fingerprint matching algorithm using both ridge features and the conventional minutiae feature to increase the recognition performance against nonlinear deformation in fingerprints. The proposed ridge features are composed of four elements: ridge count, ridge length, ridge curvature direction, and ridge type. These ridge features have some advantages in that they can represent the topology information in entire ridge patterns existing between two minutiae and are not changed by nonlinear deformation of the finger. For extracting ridge features, we also define the ridge-based coordinate system in a skeletonized image. With the proposed ridge features and conventional minutiae features (minutiae type, orientation, and position), we propose a novel matching scheme using a breadth-first search to detect the matched minutiae pairs incrementally. Following that, the maximum score is computed and used as the final matching score of two fingerprints. Experiments were conducted for the FVC2002 and FVC2004 databases to compare the proposed method with the conventional minutiae-based method. The proposed method achieved higher matching scores. Thus, we conclude that the proposed ridge feature gives additional information for fingerprint matching with little increment in template size and can be used in conjunction with existing minutiae features to increase the accuracy and robustness of fingerprint recognition systems.</P>

Mosaicing Touchless and Mirror-Reflected Fingerprint Images

Heeseung Choi,Kyoungtaek Choi,Jaihie Kim IEEE 2010 IEEE transactions on information forensics and sec Vol.5 No.1

<P>Touchless fingerprint sensing technologies have been explored to solve problems in touch-based sensing techniques because they do not require any contact between a sensor and a finger. While they can solve problems caused by the contact of a finger, other difficulties emerge such as a view difference problem and a limited usable area due to perspective distortion. In order to overcome these difficulties, we propose a new touchless fingerprint sensing device capturing three different views at one time and a method for mosaicing these view-different images. The device is composed of a single camera and two planar mirrors reflecting side views of a finger, and it is an alternative to expensive multiple-camera-based systems. The mosaic method can composite the multiple view images by using the thin plate spline model to expand the usable area of a fingerprint image. In particular, to reduce the affect of perspective distortion, we select the regions in each view by minimizing the ridge interval variations in a final mosaiced image. Results are promising as our experiments show that mosaiced images offer 29% more true minutiae and 28% larger good quality area than one-view, unmosaiced images. Also, when the side-view images are matched to the mosaiced images, it gives more matched minutiae than matching with one-view frontal images. We expect that the proposed method can reduce the view difference problem and increase the usable area of a touchless fingerprint image. Furthermore, the proposed method can be applied to other biometric applications requiring a large template for recognition.</P>

Reliability and Validity of the Korean Version of Gerry’s Assertiveness Scale for Nurses

Heeseung Choi,Yeseul Joen,Hannah Kim,Ujin Lee,Eun-Hi Kong 한국간호과학회 2021 한국간호과학회 학술대회 Vol.2021 No.10

Aim: Assertiveness, the ability to express one’s rights, thoughts, and feelings while respecting the rights of others, is an essential skill for a nurse to maintain professional boundaries and provide appropriate nursing care in healthcare settings. This study evaluated the validity and reliability of the Korean version of Gerry’s Assertiveness Scale (K-GAS) for nurses. Methods: The K-GAS was developed using a committee translation method: 1) translation by two bilingual translators, 2) back-translation by two bilingual translators, and 3) review of the accuracy and consistency of the K-GAS in the Korean cultural context by six nursing experts and two linguists. Data were collected from 252 nurses from secondary and tertiary hospitals in South Korea. Descriptive statistics, Pearson’s correlation coefficient, and Cronbach’s alpha were used to evaluate the psychometric properties of the K-GAS. Criterion validity was evaluated using Rathus’ Assertiveness Schedule. Correlations with nurses’ general characteristics and empathy competency were also examined. Results: In the item analyses, all items were retained in the final scale. For the total of 30 items, item-total correlation ranged from 0.257-0.626. Skewness (0.000-0.726) and kurtosis (0.009-0.756) for each item were acceptable and met the assumption of normal distribution. Internal consistency of the K-GAS was reliable and Cronbach’s alpha was .847. Criterion validity was identified with a high correlation with Rathus’ Assertiveness Schedule (r=.743, p<0.01). The level of assertiveness was positively associated with age (r=.167, p<0.01), professional experiences (r=.185, p<0.01), and education level (r=.128, p<0.05). Meanwhile, it was negatively associated with previous communication education (r= -.163, p<0.05) and empathy competence (r = -199, p<0.01). Conclusion: The Korean version of Gerry’s Assertiveness Scale is a valid and reliable tool for measuring the assertiveness of nurses working in hospitals. The scale could be widely used to assess assertiveness among nurses.

Clinical Education in Psychiatric Mental Health Nursing

Heeseung Choi,Boyoung Hwang,Sungjae Kim,Heesung Ko,Sumi Kim,Chanhee Kim 한국간호과학회 2015 한국간호과학회 학술대회 Vol.2015 No.10

Reliability and Validity of a Korean Version of the Cultural Awareness Scale (K-CAS)

Choi, Heeseung,Suh, Eunyoung E,Park, Chang,Park, Jisun,Fernandez, Eric 한국성인간호학회 2015 성인간호학회지 Vol.27 No.4

Age face simulation using aging functions on global and local features with residual images

Choi, Sung Eun,Jo, Jaeik,Lee, Sanghak,Choi, Heeseung,Kim, Ig-Jae,Kim, Jaihie Elsevier 2017 expert systems with applications Vol.80 No.-

<P><B>Abstract</B></P> <P>In many previous methods for facial age simulation, the shape and appearance features of Active Appearance Models (AAM) are widely used to model the global facial characteristics. However, they cannot sufficiently represent facial details such as spots, scars, fine wrinkles, and skin blemishes, because many of them are removed from the AAM features during the dimension reduction process. Therefore, previous methods are not suitable for real-world applications, such as forensics, face recognition, and entertainment production systems, which require more accurate and realistic age simulation. To overcome the limitation, this paper proposes an automatic age simulation method based on a synergetic combination of the residual image, local features, and AAM global features. The residual image, which is the difference between a facial image and its reconstructed image by using AAM features, contains facial details of the input image that are not included in the AAM features. Representation of facial details in the age simulation process is achieved by generating and adding a targeted age-weighted residual image to the facial image synthesized by the AAM features. Further, facial details such as wrinkles and skin blemishes that have not yet appeared at the current age but normally appear as aging proceeds, are supplemented, and represented by local features that show locally different aging characteristics. The experimental results show that the proposed method simulates a face more accurately and realistically than previous methods, thereby confirming that it is more suitable for the real-world applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Age simulation method using global, local features and residual image is proposed. </LI> <LI> The residual image represents the personal characteristics of the input image. </LI> <LI> Local features represent the local aging characteristics of wrinkle and skin. </LI> </UL> </P>

Psychiatric-Mental Health Nursing Education and Cultural Competence

Heeseung Choi 한국간호과학회 2018 한국간호과학회 학술대회 Vol.2018 No.1

Purpose : The objectives of the presentation are to (1) review the key concepts related to culture and mental health; and (2) to discuss the process for developing and implementing a graduate course which was designed to foster nurses’ understanding of the influence of various cultures (e. g., racial, ethnic, socio-economic, educational, and geographic) on mental health and nursing care. This abstract mainly focuses on the qualitative research study process that has been used to develop the graduate course. Methods : First, qualitative descriptive study design was used to (1) explore Korean nursing students’ nursing care experiences with patients from diverse cultural backgrounds; and (2) explore Korean nursing students’ needs for cultural competence education integrated into the nursing curriculum. Undergraduate and graduate students attending one of the nursing schools in Korea participated in the focus group. Next, new graduate course was developed based on the findings from the focus group interviews. Results : A total of 18 undergraduate and 20 graduate students (n = 38) participated in one of six focus groups. The findings from the qualitative data demonstrated that participants have encountered their boundaries and prejudices when caring for ethnically-diverse patients. The participants described their experience of caring for patients from diverse cultural backgrounds as “encountering the boundaries of my taken-for-granted world” and “being aware of the core nature of human communication and caring.” The findings confirmed that the interaction between two cultures is reciprocal and that health care providers and patients were mutually influenced by each other. The findings of this study were incorporated into the nursing curriculum and I developed and offered a new graduate course for nursing students, called “Sociocultural diversity and health.” A total of 22 students completed the course and reported that they experienced self-reflection and became more sensitive to the power imbalance between health care providers from dominant cultures and patients from different cultural backgrounds. Conclusions : More courses addressing cultural diversity and cultural competence should be developed for nursing student who are working for patients from diverse cultural backgrounds.

Applying the Flipped Learning Model to an English-Medium Nursing Course

Choi, Heeseung,Kim, Jeongeun,Bang, Kyung-Sook,Park, Yeon-Hwan,Lee, Nam-Ju,Kim, Chanhee 한국간호과학회 2015 Journal of Korean Academy of Nursing Vol.45 No.6

Purpose: An emerging trend in Asian higher education is English-medium instruction (EMI), which uses English as the primary instructional language. EMI prepares domestic students for international leadership; however, students report difficulty in learning, and educators have raised questions concerning the effectiveness of EMI. The flipped learning model (FLM), in which lecture and homework activities for a course are reversed, was applied to an English-medium course offered by a college of nursing in Korea. The aims of this study were to: 1) revise an existing English-medium nursing course using the FLM; 2) explore students’ learning experiences and their acceptance of the FLM; and 3) identify key factors in the success of FLM. Methods: We used a descriptive, cross-sectional, mixed-methods design and the participants were students at one nursing school in Korea. A series of course development meetings with faculties from the nursing school and the center for teaching and learning were used to develop the course format and content. We conducted course evaluations using the Flipped Course Evaluation Questionnaire with open-ended questions and focus group interviews. Results: Students (N=75) in a 15-week nursing course responded to a survey after completing the course. Among them, seven students participated in one of two focus groups. Overall, students accepted and favored the flipped learning strategy, and indicated that the method enhanced lecture content and their understanding of it. Factors associated with effective instruction included structured monitoring systems and motivational environments. Conclusion: The FLM requires sufficient preparation to facilitate student motivation and maximize learning outcomes.

Aliveness detection of fingerprints with Image Quality Analysis

Heeseung Choi,Kyungtaek Choi,Jaihie Kim 대한전자공학회 2008 ICEIC:International Conference on Electronics, Inf Vol.1 No.1

Fake finger submission to the sensor is a major problem in fingerprint recognition systems. In this paper, we introduce a novel aliveness detection method with image quality analysis. For convenience and usefulness of field application, multiple static features are considered to detect ‘live’ and ‘fake’ fingerprint images. Power spectrum, directional contrast and ridge thickness of image are analyzed. Our static features can reflect the physiological and statistical characteristics of live and fake fingerprint. Aliveness score of each feature is calculated and fused in feature level through polynomial SVM (Support Vector Machine) classifier. In our data set, proposed method has approximately 0.49% EER (Equal Error Rate) at best only using a single image. Our approach will provide a faster and useful technique for aliveness check for field applications.