• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.529-535
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• 2018

The range extender vehicle runs on a mechanism that allows the small power generation engine to start in the most efficient specific operating range to charge the battery and extend the mileage. In this study, we developed a step motor type intake air supply system that replaces existing throttle body system to develop a simple low cost control logic system. The system was applied to the existing base engine, and in order to improve the performance by increasing the amount of intake air, the effect of changing the length of the intake and exhaust manifold was experimentally examined. As a result, the Type B intake air control actuator operated by one step motor showed higher performance than the Type A in all the operation region, but the performance was lower than that of the base engine due to the increase of flow resistance. To improve this, it was confirmed that the engine performance was improved at both speeds of 2200rpm and 4300rpm when the 140mm adapter was installed in the intake manifold and when the newly designed 70mm exhaust manifold was applied. Through this process, high - precision operation control was realized by connecting the generator load to the optimized engine for the range extender electric vehicle. Experimental results showed that the speed change rate was within ${\pm}2.5%$ at 2200rpm in 1st stage and 4300rpm in 2nd stage and the speed follow-up result of 610 rpm/s was obtained when the speed was increased from 2200rpm to 4300rpm.

• Journal of Industrial Convergence
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• v.19 no.5
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• pp.21-34
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• 2021

The purpose of this study is to find out what the investment efficiency of BW is from an investor's point of view and to suggest an efficient investment plan to investors. The research method is to investigate the coupon interest rate, maturity interest rate, issuance date, right exercise start and end date, maturity date, exercise price, etc. for BW issued from 2014 to July 2021. By connecting them, it was attempted to quantitatively understand the efficiency of investment in BW and the effect of new stock acquisitions. As a result of the study, the ratio of the number of days in excess of the exercise price was 41.3% of the available days for new stocks, so it was analyzed that the investment efficiency of bonds with warrants was not high. The return on the exercise start date was 24.8% on average and the return on the end date was 52.6% on average, showing a positive return on average, so it was derived in line with investor expectations. The number of stocks with negative returns on the exercise start date was 1.47 times higher than the number of stocks with positive returns, and the number of stocks with negative returns on the end date was 1.16 times higher than the number of positive stocks.

• Science of Emotion and Sensibility
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• v.25 no.3
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• pp.77-90
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• 2022

This study seeks to develop a stretch sensor for measuring the wrist movements of people using fishing lures. In order to confirm wrist movement, a stretch sensor was attached to the wrist band, and measurements of the dorsiflexion, plantar flexion, and fishing landing motion were measured using a scale to gauge factor, tensile strength, and elongation recovery rate. A conductive sensor using CNT dispersion was developed and applied to the E-band under the same conditions. A total of 15 sensors of the same size and five types of impregnation once, twice, and three times each were used to measure the gauge factor using UTM. The sensor that was impregnated twice had the best gauge rate, and the prototypes were manufactured with three sensors with high gauge rates and tensile strength. The results of the operation test conducted by connecting to the Arduino showed that Sample 1, which had the highest tensile strength and gauge factor, had a stable graph wavelength in three operations. Samples 2 and 3 showed stable wavelengths in the dorsiflexion and the plantar flexion; however, signal noise appeared in the fishing landing motion. This showed stable wavelengths in the two motions, but the wavelengths of the graphs differ depending on the tensile strength and gauge factor in the fishing landing motion. As a result, it was possible to identify the conditions necessary for manufacturing a stretch sensor for measuring wrist movement. This study will contribute to the development of smart wearable products for lure fishing.

• Journal of the Korean Society of School Health
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• v.11 no.2
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• pp.171-187
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• 1998

In recent years, adolescent issues including smoking, drinking, drug abuse, juvenile delinquency, deviant sexual behavior, mental health problems, high suicide rate, juvenile delinquency and absence without due notice, etc are emerging as serious social problems and the debate on these controversial issues is heating up. The previous studies on adolescent health behavior and social juvenile delinquency such as run-away from home and absence without due notice have been conducted mostly by cause analysis utilizing social demographic factors or biological factors. In other words, the main factors analyzed were demographic and economic factors or parent's educational level, etc, which were the fixed environmental ones that were unable to cause the change in the health behavior. Accordingly, the purpose of this study is to analyze factors which are changeable and fixable among the factors influencing the adolescent's health behavior and misconducts and, eventually influencing factors which can be used as the basis to establish health policies and health promotion program to reduce the health risk behavior and misconducts of adolescents. The study subjects were selected by dividing senior high school student in Seoul by region and through random sampling. The 890 subjects were selected from 10 schools including the preparatory school, vocational schools and institutional schools. The duration of the study was for July 1-5, 1997 for the first survey and the second one, for August 25-September 10. Regarding the analysis method, the SAS program was used. The adoptablity of theoretical model was tested through covariance structural analysis utilizing PC-LISREL 8.12 Program. The major findings of the study are as follows: As a result of establishing the model of factors influencing health behavior and juvenile delinquency, in case of male students as the health behavior self-efficacy, education level of fathers, economic level, self-control and the health interest of parent were higher, students were more likely to practice the health promoting behavior. Juvenile delinquency and health risk behavior were prevalent among those with the less shyness, the lower health behavior self-efficacy, lower self-control, lower self-assertiveness, lower economic level. The self-control was the most powerful factor. In case of female students, those with higher health behavior self-efficacy were more likely to practice the health promoting behavior whereas those with lower health behavior self-efficacy, lower self-control, lower self- assertiveness, less shyness were more likely to practice health risk behavior and juvenile delinquency. In case of prep schools, those with higher health behavior self-efficacy and better perceived health status were more likely to practice the health promoting behavior while those with less shyness, lower health behavior self-efficacy and lower academic achievement were more likely to engage in health risk behavior and juvenile delinquency. In case of vocational schools, as health behavior self-efficacy and economic level were higher, the practice rate of health promoting behavior was higher. As the self-control, shyness, self-assertiveness, health behavior self-efficacy were lower, the rate of health risk behavior and juvenile delinquency were higher. In case of social institutional schools, as, the health behavior self-efficacy, social support and economic level, health interest of parents were higher, the rate of health promoting behavior were higher. As the self-control, shyness, self-assertiveness, health behavior self-efficacy and social support were lower, the rate of health risk behavior and juvenile delinquency were higher. So the health promoting behavior was positively related to the health behavior self-efficacy, health interest of parents, social support, education level of fathers, level of perceived health status, economic level. The health risk behavior and juvenile delinquency were higher with the lower health behavior self-efficacy, self-control and self-assertiveness, lower health locus control, less shyness and loneliness, lower economic level and academic achievement. In conclusion, the health risk behavior and juvenile delinquency can be reduced by enhancing self-control, self-assertiveness, health behavior self-efficacy and social support. According to the final model drawn by connecting health behavior and juvenile delinquency, the reduction of health risk behavior can greatly contribute to decreasing social juvenile delinquency as the process of juvenile delinquency was extended from common behaviors to problem behaviors and further into juvenile delinquency.

• Korean Journal of Psychosomatic Medicine
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• v.12 no.2
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• pp.145-156
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• 2004

Objectives : Internet addiction is a newly appeared addictive phenomenon that is defined as 'difficulty in real life due to internet over-use', 'excessive time spent on the internet or replacement of genuine real relationships with superficial virtual ones' or 'weakness in self-control about internet use and if discontinued, fallen in psychological confusion and anergic state'. This study was aimed to compare the internet addiction rate, demographic factors, computer using patterns, anxiety, depression, and internet self-efficacy and outcome expectancy between Korean middle and high school students in three areas - Seoul, Cheonan, and Rural areas - that were different in economic, cultural, and geographic state. Methods : Subjects are consisted of middle and high school students in Seoul, Chunan, and Rural areas(N=1718). Self-rating questionnaire included demographic data, Korean Spielberger State-Trait Anxiety Inventory, Korean Self-Rating Depression Scale(SDS), questions for internet-using pattern, Korean version of Internet Addiction Scale invented by K. S. Young, Internet Self-efficacy and Out-come Expectancy Scale. Results: In this study, prevalence of internet addiction was 2.9%. There was no significant difference found in prevalence of internet addiction among three areas. In all subjects, there were significant differences in anxiety, depression, internet self-efficacy and outcome expectancy, leisure style, places of internet use, internet connecting method, and insight on internee addiction. But, in addicted group, there was no significant difference among three areas. Conclusion: This study suggested that the difference in economic, cultural, and geographic state was not related to prevalence of internet addiction. Although there were significant differences in anxiety, depression, self-efficacy associated with internee use, leisure style, places of internet use, internet connecting method, insight on internet addiction among three areas, there were no significant difference in addicted group among three areas. So, we concluded that the difference in economic, cultural, and geographic state did not influence the prevalence of internet addiction, and despite the difference in economic, cultural, and geographic state, people in three areas were equally influenced by internet addiction.

• Journal of architectural history
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• v.3 no.1
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• pp.83-99
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• 1994

Ch'ang-Ts'al-Ts'un is a rural Village near Lung-jing City in Yen-pien Korean Autonomous Province of China. It was formed about 100 years ago by Korean Immigrants and has been developed maintaing the characteristics of traditional Korean architecture. Therefore investigating the spatial structure of this village is a meanigful work to confirm and explore one branch of Korean architecture. This study aims at analyzing the spatial structure of the village using direct data collected from the field work and indirect data from books and maps. The field work consists of on-the-site survey of the village layout, interviews of residents, observation notes and photography. Ch'ang-Ts'ai-Ts'un is located 360-370 m high above the sea level and at the side of a long valley. A river flows in the middle of the valley and relatively flat arable land exists at the both sides of the river. The location of the village related to the surrounding river and mountains suggests that the site of the village was chosen according to Feng-Shui, Chinese and Korean traditional architectural theory. The main direction of the house layouts is South-western. The village has been growing gradually until today. Therefore it is meaningful to make the village layout before Liberation(1946 A.D.) because the characteristics of Korean architecture prevailed more in that period. The area of the previous village is limited to the west side of the creek. New houses were later added to the east of the creek, forming a 'New Village'. Previously the village was composed of 3 small villages: Up, Middle and Down. Also the main access roads connecting the village with the neighboring villages were penetrating the village transversely. Presently the main access road comes to the village longitudinally from the main highway located in front of the village. The retrospective layout shows the existence of well-formed Territory, Places and Axes, thus suggesting a coherent Micro-cosmos. The boundary of imaginery territory perceived by present residents could be defined by linking conspicous outside places sorrounding the village such as Five-mountains, Front-mountain, Shin-dong village, Standing-rock, Rear-mountain and Myong-dong village. Inside the territory there are also the important places such as Bus-stop, Memorial tower of patriots, Road-maitenance building and the village itself. And inside it 5 transverse and 1 longitudinal axes exist in the form of river, roads and mountains. The perceived spatial structure of the village formed by Places, Axes and Territory is geometrical and well-balanced and suggests this village is fit for human settlement. The administrative area of the village is about 738 ha, 27 % of which is cultivated land and the rest is mountain area. Initially the village and surrounndings were covered with natural forest But the trees have been gradually cut down for building and warning houses, resulting in the present barren and artificial landscape with bare mountains and cultivated land. At present the area of the village occupied by houses is wedge-shaped, 600 m wide and 220 m deep in its maximum. The total area of the village is $122,175m^{2}$. The area and the rate of each sub-division arc as follow. 116 house-lots $91,465m^{2}$ (74.9 %) Land for public buildings and shops $2,980m^{2}$ (2.4 %) Roads $17,106m^{2}$ (14.0 %) Creek $1,356m^{2}$ (1.1 %) Vacant spaces and others $9,268m^{2}$ (7.6 %) TOTAL $122,175m^{2}$ (100.0 %) Each lot is fenced around with vertical wooden pannels 1.5-1.8 m high and each house is located to the backside of the lot. The open space of a lot is sub-divided into three areas using the same wooden fence: Front yard, Back yard and Access area. Front and back yards are generally used for crop-cultivation, the custom of which is rare in Korea. The number of lots is 116 and the average size of area is $694.7m^{2}$. Outdoor spaces in the village such as roads, vacant spaces, front yard of the cultural hall, front yard of shops and spacse around the creek are good 'behavioral settings' frequently used by residents for play, chatting, drinking and movie-watching. The road system of the village is net-shaped, having T-junctions in intersections. The road could be graded to 4 categories according to their functions: Access roads, Inner trunk roads, Connecting roads and Culs-de-sac. The total length of the road inside the village is 3,709 m and the average width is 4.6 m. The main direction of the road in the village is NNE-SSE and ESE-WNW, crossing with right angles. Conclusively, the spatial structure of Ch'ang-Ts'ai-Ts'un village consists of various components in different dimensions and these components form a coherent structure in each dimension. Therefore the village has a proper spatial structure meaningful and appropriate for human living.

• Korean Journal of Environment and Ecology
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• v.37 no.6
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• pp.429-438
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• 2023

The forest in the lower Tumen River serves as an important ecosystem spanning the territories of North Korea, Russia, and China, and it provides habitat and movement corridors for diverse mammals, including the endangered Amur tiger (Panthera tigris) and Amur leopard (Panthera pardus). This study focuses on the Mijiang area, situated as a potential ecological corridor connecting North Korea and China in the lower Tumen River, playing a crucial role in conserving and restoring the biodiversity of the Korean Peninsula. This study aimed to identify mammal species and estimate their relative abundance, occupancy, and distribution based on the 48 camera traps installed in the Mijiang area from May 2019 to May 2021. The results confirmed the presence of 18 mammal species in the Mijiang area, including large carnivores like tigers and leopards. Among the dominant mammals, four species of ungulates showed high occupancy and detection rates, particularly the Roe deer (Capreolus pygargus) and Wild boar (Sus scrofa). The roe deer was distributed across all areas with a predicted high occupancy rate of 0.97, influenced by altitude, urban residential areas, and patch density. Wild boars showed a predicted occupancy rate of 0.73 and were distributed throughout the entire area, with factors such as wetland ratio, grazing intensity, and spatial heterogeneity in aspects of the landscape influencing their occupancy and detection rates. Sika deer (Cervus nippon) exhibited a predicted occupancy rate of 0.48, confined to specific areas, influenced by slope, habitat fragmentation diversity affecting detection rates, and the ratio of open forests impacting occupancy. Water deer (Hydropotes inermis) displayed a very low occupancy rate of 0.06 along the Tumen River Basin, with higher occupancy in lower altitude areas and increased detection in locations with high spatial heterogeneity in aspects. This study confirmed that the Mijiang area serves as a habitat supporting diverse mammals in the lower Tumen River while also playing a crucial role in facilitating animal movement and habitat connectivity. Additionally, the occupancy prediction model developed in this study is expected to contribute to predicting mammal distribution within the disrupted Tumen River basin due to human interference and identifying and protecting potential ecological corridors in this transboundary region.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.1
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• pp.12-24
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• 2018

This study was conducted in order to improve opening efficiency of the miniaturized large-scale net for anchovy boat seine gear to reduce the fleet size. Field experiments were performed to observe geometry of nets by catcher boats. When the distances between the two ships were 150, 300 and 450 m, and the speeds of towing nets were 0.6, 0.9, and 1.2 k't, respectively. The vertical opening and actual opening of each part of the miniaturized large-scale net was as follows: the front part of the wing net, 8.7-13.3 m, 51-78%; the middle part of the wing net, 28.1-34.2 m, 55-67%; the entrance of the inside wing net, 31.3-38.5 m, 60-73%; the square and bosom, 22.7-29.6 m, 47-62%; the entrance of the body net, 20.9-26.4 m, 42-52%; the entrance of the bag net, 17.2-21 m, 72-89%; the flapper, 13.2-15.3 m, 78-83%; and the end of the bag net, 13.2-15.7 m, 72-75%. By connecting the net pendants with the front part of the wing net, the opening of the front part of the wing net was significantly improved compared to the traditional gear, which ensured both the wing net and the inside wing net with a normal net height. This, in turn, increased the efficiency of herding. The height of the body and bag nets was also higher than that of the tradition gear. In particular, the body net attached to the gear significantly improved the pocket shape of the gear and reduced the number of fish that were caught and escaped from the bag net, which increased the rate of fishing. The tension of towing nets was measured approximately between 2,958 and 7,110 kg, which indicates that the fleet can tow nets with 350 ps, the standard engine horse power. The fishing operation time was shortened compared with of the existent net, and the large-scale buoy attachment operation was also possible to operate the ship without fish detecting boat.

• Proceedings of the Korea Contents Association Conference
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• 2004.11a
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• pp.327-332
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• 2004

USB(Universal Serial Bus) is one of the most popular communication interfaces. When USB is used in an extended range, especially configurating In-home network by connecting multiple digital devices each other, USB interface uses the bandwidth in the way of TDM(Time Division Multiplexing) so that the bottleneck of bus bandwidth can be brought. In this paper, the more effective usage of bus bandwidth to overcome this situation is introduced. Basically, in order to realize the system for transferring realtime moving picture data among digital information devices, we analyze USB transfer types and Descriptors and introduce the method to upgrade detailed performance of Isochronous transfer that is one of USB transfer types. In the case that Configuration descriptor of a device has Interface descriptor that has two AlternateSetting, if Isochronous transfers are not processed smoothly due to excessive bus traffic, the application of the device changes AlternateSetting of the Interface descriptor and requires a new configuration by SetInterface() request. As a result of this adaptive configuration, the least data frame rate is guaranteed to a device that the sufficient bandwidth is not alloted. And if the bus traffic is normal, the algorithm to return to the original AlteranteSetting is introduced. this introduced method resolve the bottleneck of moving picture transfer that can occur in home network connected by multiple digital devices.

• Journal of KIISE:Software and Applications
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• v.29 no.11
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• pp.809-817
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• 2002

This paper describes a new face detection method that is a pre-processing algorithm for on-line face recognition. To complement the weakness of using only edge or rotor features from previous face detection method, we propose the two types of face detection method. The one is a combined method with edge and color features and the other is a center area color sampling method. To prevent connecting the people's face area and the background area, which have same colors, we propose a new adaptive edge detection algorithm firstly. The adaptive edge detection algorithm is robust to illumination variance so that it extracts lots of edges and breakouts edges steadily in border between background and face areas. Because of strong edge detection, face area appears one or multi regions. We can merge these isolated regions using color information and get the final face area as a MBR (Minimum Bounding Rectangle) form. If the size of final face area is under or upper threshold, color sampling method in center area from input image is used to detect new face area. To evaluate the proposed method, we have experimented with 2,100 face images. A high face detection rate of 96.3% has been obtained.