• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.3
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• pp.99-104
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• 2002

lateral insulated gate bipolar transistors(LIGBTs) are extensively used in high voltage power IC application due to their low forward voltage drops. One of the main disadvantages of the LIGBT is its scow switching speed when compared to the LDMOSFET. And the LIGBT with reverse channel structure is lower current capability than the conventional LIGBT at the forward conduction mode. In this paper, the LIGBT which included p+ ring and p-channel gate is presented at the reverie channel structure. The presented LIGBT structure is proposed to suppress the latch up, efficiently and to improve the turn off time. It is shown to improve the current capability too. It is verified 2-D simulator, MEDICI. It is shown that the latch up current of new LIGBT is 10 times than that of the conventional LIGBT Additionally, it is shown that the turn off characteristics of the proposed LIGBT is i times than that of the conventional LIGBT. It is net presented the tail current of turn off characteristics at the proposed structure. And the presented LIGBT is not n+ buffer layer because it includes p channel gate and p+ ring.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1547-1549
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• 1996

The electrical and optical switching characteristics of gold-doped silicon p-i-n diodes have been investigated. The device shows a dark switching voltage of about 500 V. The switching voltage decreases rapidly when the illumination level is increased. The differential sensitivity of optical gating over linear region is $d(V_{Th}/V_{Tho})/dP_{Ph}$=0.25/uW. The turn-on delay time and the turn-on rise time decrease with increasing optical pulse power. The turn-off delay and the fall time are negligible.

• Journal of Industrial Technology
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• v.22 no.A
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• pp.73-82
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• 2002

It is difficult to find the shortest paths using existing algorithms (Dijkstra, Floyd-Warshall algorithm, and etc) in high complex and large size real traffic networks The objective of this paper is to develop an evolution program to find the multiple shortest paths within reasonable time in these networks including turn-restrictions, U-turns, and etc.

• Journal of Korean Clinical Nursing Research
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• v.18 no.3
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• pp.329-340
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• 2012

Purpose: This study was done to identify internal marketing activity, emotional labor and work-family conflict that influence turn-over in hospital nurses. Methods: Participants were 513 nurses from 2 general hospitals in Chung-nam and Gyeonggi Provinces, South Korea. Data were collected from September 1 to 30, 2011 using self-report questionnaires. Stepwise multiple regression was used to identify association between variables. Results: The mean score for internal marketing activity was $94.7{\pm}14.7$, emotional labor, $31.4{\pm}5.5$, work-family conflict, $19.6{\pm}4.1$, and turn-over, $13.7{\pm}3.4$. After adjusting for general characteristics, stepwise multiple regression showed that work-family conflict (${\beta}=.20$, p<.001), marketing activity (${\beta}=-.21$, p<.001), and emotional labor (${\beta}=.22$, p<.001) were associated with turn-over. These predictors accounted for 33% of variance in turn-over. Conclusion: The results of this study show that work-family conflict was the most influential predictor indicating a need for the development of strategies to reduce work-family conflict and emotional labor. At the same time internal marketing activity should be supported in the hospital by analyzing the needs for nurses. Also career development programs and mentor systems will be useful for effective manpower management and quality improvement of nursing services.

• Physical Therapy Rehabilitation Science
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• v.7 no.2
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• pp.54-60
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• 2018

Objective: Persons with chronic stroke fall more often than healthy elderly individuals. The Timed Up and Go test (TUG) is used as a fall prediction tool, but only provides a result for the total measurement time. This study aimed to determine the optimal cut-off values for each of the 6 components of the TUG. Design: Retrospective study. Methods: Thirty persons with chronic stroke participated in the study. TUG evaluation was performed using a wearable miniaturized inertial sensor. Sensitivity, specificity, and predictive values were calculated using the Receiver Operating Characteristic (ROC) curve analysis for the measured values in each section. Optimal values for fall risk classification were determined. Logistic regression analysis was used to investigate the risk of future falls based on TUG. Results: The cut-off values of the 6 sections of the TUG were determined, as follows: sit-to-stand >2.00 seconds (p<0.05), forward gait >4.68 seconds (p<0.05), mid-turn >3.82 seconds (p<0.05), return gait >4.81 seconds (p<0.05), end-turn >2.95 seconds (p<0.05), and stand-to-sit >2.13 seconds (p<0.05). The risk of falling increased by 2.278 times when the mid-turn value was >3.82 seconds (p<0.05). Conclusions: The risk of falls increased by 2.28 times when the value of the mid-turn interval exceeded 3.82 seconds. Therefore, when interpreting TUG results, the predictive accuracy for falls will be higher when the measurement time for each section is analyzed, together with the total time for TUG.

• The Transactions of the Korean Institute of Power Electronics
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• v.3 no.4
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• pp.418-425
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• 1998

In this paper. determination method of turn-off angle in the SRM drives is proposed to maintain the high torque at a any turn-on angle, which is realized by using selHuning control method, During the sampling time. a number of P pulses from encoder are checked by using one-chip microprocessor. and compared with pre-checked a number of pulses A After calculating difference between two data, the turn-off angle moves forward or backward direction by the self-tuning m method, As repeating such process, the optimal turn-off angle is determined and the maximum torque is maintained T Though experiments, it is observed that motor speed is almost maintained if turn-off angle is adjusted automatically by s selHuning method when turn-ηn angle is changed.

• Journal of Korean Society of Transportation
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• v.21 no.6
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• pp.89-99
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• 2003

Considering a path represented by a sequence of link numbers in a network, the vine is differentiated from the loop in a sense that any link number can be appeared in the path only once, while more than once in the loop. The vine provides a proper idea how to account for complicated travel patterns such as U-turn and P-turn witnessed nearby intersections in urban roads. This paper proposes a new algorithm in which the vine travel pattern can be considered for finding K number of sequential paths. The main idea of this paper is achieved by replacing the node label of the existing Yen's algorithm by the link label technique. The case studies show that the algorithm properly represent the vine travel patterns in searching K number of paths. A noticeable result is that the algorithm may be a promising alternative for ITS deployment by enabling to provide reasonable route information including perceived traveler costs.

• IE interfaces
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• v.14 no.4
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• pp.374-384
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• 2001

The objective of this paper is to design the dynamic route guidance system(DRGS) and develop a genetic algorithm(GA) for finding the multiple shortest paths in real traffic network. The proposed GA finds a collection of paths between source and destination considering turn-restrictions, U-turn, and P-turn that are genetically evolved until an acceptable solution is reached. This paper also shows the procedure to find the multiple shortest paths in traffic network of Seoul.

• Journal of The Korean Society of Integrative Medicine
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• v.12 no.3
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• pp.189-199
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• 2024

Purpose : This study aimed to investigate the test-retest reliability, minimal detectable change (MDC), and the effect of turning direction on the time and number of steps taken during the 180 ° turn test in subacute stroke patients. Additionally, it examined the concurrent validity of the 180 ° turn test. Methods : The study included 28 subacute stroke patients. The test-retest reliability of the 180 ° turn test according to the direction of rotation (paretic and non-paretic sides) by comparing the consistency between the initial assessment and a reassessment conducted 7 days later. Concurrent validity was examined by assessing the correlation of the 180 ° turn test with the Fugl-Meyer assessment of lower extremity (FMA-L/E), Berg balance scale (BBS), 10-meter walk test (10 mWT), and timed up and go test (TUG). Results : The ICC for the time taken to turn 180 ° to the affected and unaffected sides were 0.971 and 0.918, respectively, indicating excellent reliability. The ICC for the number of steps were 0.944 and 0.932, respectively. The MDC for the time taken were 0.33 seconds (affected side) and 0.67 seconds (unaffected side). The MDC for the number of steps were 0.49 (affected side) and 0.63 (unaffected side). The paired t-test showed the limited community ambulator group took significantly longer to turn to the unaffected side (p<.048). Significant correlations were found between the 180 ° turn test and FMA-L/E (r= -0.395 to -0.416), BBS (r= -0.622 to -0.684), 10 mWT (r= 0.720 to 0.730), and TUG (r= 0.684 to 0.790) (p<.05 to .01). Conclusion : The 180 ° turn test demonstrated excellent test-retest reliability and high validity when correlated with other functional measures in subacute stroke patients. MDC values indicated high reliability. Faster walking speeds (≥0.95 m/s) were unaffected by turning direction, while slower speeds (<0.58 m/s) showed significant effects. The 180 ° turn test is a simple, sensitive, and reliable tool for evaluating turning ability in subacute stroke patients.

• Journal of Korean Society of Transportation
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• v.17 no.3
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• pp.73-85
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• 1999

In metropolitan area, intersections having turn Prohibitions are often found and it is important to consider them in path planning. This Paper presents a new path planning method road networks having turn prohibitions. A new road network model is proposed in which an alter-native route for each turn-Prohibition is constructed in off-line using U-turn or P-turn and then Put into road network database. The proposed network model is efficient since it requires no virtual nodes that are usually used in the conventional road networks to represent turns at intersections. In order to find a shortest path with the proposed network, a new shortest path algorithm is proposed. A knot for the turn-Prohibited node is newly defined and is used in comparing the cost of the alternative route with that of the other path.