• Journal of Animal Science and Technology
• /
• v.46 no.5
• /
• pp.773-782
• /
• 2004

The objective of this work was to establish an approaching method for TMR feeding system in the farm situation by testing the effects of herd-mix feeding system on the performance of lactating cows. Fifty six Holstein cows were fed for the experimental period of 16 months. Prior to test the herd-mix feeding system, animals were kept on conventional feeding system for 4 months, separate feeding of forage with concentrate, then provided 3 types of herd-mix rations formulated by mean level of energy concentration requirement of higher 1/2 ranker in each herd for remaining 12 months to compare the effect on milk yield performance of animals with conventional feeding system by using a switch-over method. The herd-mix feeding system influenced substantially upon the improvements of milk yield(P<0.01) and milk fat percentage(P<0.05). In all of lactational ages, milk yield and milk fat were enhanced by the herd-mix feeding system. Especially, actual milk yield(AMY) and milk fat in the 1st lactating cows, and AMY and 4.0% fat corrected milk yield(FCM) in the 2nd lactating cows were increased signiticantly by the herd-mix feeding system(P<0.05). In the early and mid-stage of lactation, the herd-mix feeding system showed higher AMY and FCM compared with the conventional feeding system although the milk fat was not different. AMY, milk fat and FCM in the late-stage of lactation were increased generally by the herd-mix feeding system. Especially, milk fat and FCM obtained by the herd-mix feeding system were significantly higher than those by the conventional feeding system(P<0.01). The herd-mix feeding system showed a good type of milking curve with a higher persistency of FCM(93.24%) than in conventional one(92.69%). The income over feed cost with the herd-mix feeding system was lA-fold higher than that with the conventional feeding method. In conclusion, the results of this work suggest that the herd-mix feeding system based on a correct level of energy concentration of TMR and well-determined feed ingredients increases not only milk yield of dairy herd by enhancing the performance of cows in early to mid stage of lactation with improved milk persistency but also gross income of dairy farm.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.11 no.1
• /
• pp.81-89
• /
• 2017

In this paper, we propose a gait pattern recognition method for intelligent prosthesis that enables walking in various environments of femoral amputees. The proposed gait mode changing method is a single sensor based algorithm which can discriminate gait surface and gait phase using only strain gauges sensor, and it is designed to simplify the algorithm based on multiple sensors of existing intelligent prosthesis and to reduce cost of prosthesis system. For the recognition algorithm, we analyzed characteristics of the ground reaction force generated during gait of normal person and defined gait step segmentation and gait detection condition, A gait analyzer was constructed for the gait experiment in the environment similar to the femoral amputee. The validity of the paper was verified through the defined detection conditions and fabricated instruments. The accuracy of the algorithm based on the single sensor was 95%. Based on the proposed single sensor-based algorithm, it is considered that the intelligent prosthesis system can be made inexpensive, and the user can directly grasp the state of the walking surface and shift the walking mode. It is confirmed that it is possible to change the automatic walking mode to switch the walking mode that is suitable for the walking mode.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.17 no.10 s.113
• /
• pp.967-975
• /
• 2006

In this paper, design and implementation of a very compact and cost effective front-end module are presented for IEEE 802.16 FWA(fixed Wireless Access) in the 40 GHz band. A multi-layer LTCC(Low Temperature Co-fred Ceramic) technology with cavity process to achieve excellent electrical performances is used to fabricate the front-end module. The wirebond matching circuit design of switch input/output port and waveguide transition to connect antenna are optimally designed to keep transmission loss low. To reduce the size of the front-end module, the dielectric waveguide filter is developed instead of the metal waveguide filter. The LTCC is composed of 6 layers(with the thickness of a layer of 100 um) having a relative dielectric constant of 7.1. The front-end module is implemented in a volume of $30{\times}7{\times}0.8mm^3$ and shows an overall insertion loss < 5.3 dB, and image rejection value > 49 dB.

• Transactions of the Korean hydrogen and new energy society
• /
• v.24 no.3
• /
• pp.223-229
• /
• 2013

Polymer Electrolyte Membrane Fuel Cell (PEMFC) is a power generation system to convert chemical energy of fuels and oxidants to electricity directly by electrochemical reactions. As a catalyst support for PEMFCs, carbon black has been generally used due to its large surface area and high electrical conductivity. However, under certain circumstances (start up/shut down, fuel starvation, ice formation etc.), carbon supports are subjected to serve corrosion in the presence of water. Therefore, it would be desirable to switch carbon supports to corrosion-resistive support materials such as metal oxide. $TiO_2$ has been attractive as a support with its stability in fuel cell operation atmosphere, low cost, commercial availability, and the ease to control size and structure. However, low electrical conductivity of $TiO_2$ still inhibits its application to catalyst support for PEMFCs. In this paper, to explore feasibility of $TiO_2$ as a catalyst support for PEMFCs, $TiO_2$ nanofibers were synthesized by electrospinning and calcinated at 600, 700, 800 and $900^{\circ}C$. Effects of calcination temperature on crystal structure and electrical conductivity of electrospun $TiO_2$ nanofibers were examined. Electrical conductivity of $TiO_2$ nanofibers increased significantly with increasing calcination temperature from $600^{\circ}C$ to $700^{\circ}C$ and then increased gradually with increasing the calcination temperature from $700^{\circ}C$ to $900^{\circ}C$. It was revealed that the remarkable increase in electrical conductivity could be attributed to phase transition of $TiO_2$ nanofibers from anatase to rutile at the temperature range from $600^{\circ}C$ to $700^{\circ}C$.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.17 no.2
• /
• pp.61-71
• /
• 2014

A river fishway is a hydraulic structure enabling fish to overcome stream obstructions such as dams and weirs. The main aim of this paper is to investigate the collectibility of upstream-migrating fishes and hydraulic problems in pool-and-weir type fishway which has been established for upstream-migration at Namgang weir in the downstream of Namgang dam, and to grope for improvement measures which pool-and-weir type fishway can be switched to pool-and-partial weir type fishway through hydraulic field experiment. Exsisting fishway had problems which upstream-migrating fishes can not take a rest due to the seiche and vortex phenomena in pools and migrate to upstream because of height difference in entrance pool. In order to prevent hydraulically the seiche and vortex phenomena and establish rest area for fishes in each pool, we carried out hydraulic field experiments. In the fishway, it was to improve pool-and-weir into pool-and-partil weir, to decrease the height difference in entrance pool, and to reduce oriffice velocity of each pool. Also, we investigated fishes collectibility of after improving fishway for 6 days in September 2013. To resolve chronic problems(seiche-vortex phenomena and rest area for fishes), as weirs were remodeled into partial weir only which central part of weirs was part of non-overflow weir, we confirmed results that pool-and-weir type fishway could be switched to efficient pool-and-partial weir type fishway with relatively simple construction and low cost. Type-B which has the closed oriffices and the parts of non-overflow has the ideal conditions, but this conditions are limited to fishway of Namgang weir used in this study. Representative Ice-habor type fishway is pool-and-partial weir type fishway which has together parts of overflow and oriffices, and has excellent ability of upstream-migration. To switch from pool-and-weir type fishway to pool-and-partial weir type fishway, the size of oriffice has to be regulated by the discharge of fishway and the dimension on parts of non-overflow and overflow in weirs. Entrance pool is important facility which upstream-migrating fishes have to not only be collect but also charge with energy. In this study, entrance-pool is temporary and roughly-built, but fishes gather together more than the case of no entrance-pool. In the case of fishway which was protruded to downstream, as entrance of fishway turns toward or parallels to weir, the collectibility of fishway was excellent by attraction water.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.25 no.4
• /
• pp.863-872
• /
• 2015

Kernel rootkit is recognized as one of the most severe and widespread threats to corrupt the integrity of an operating system. Without an external monitor as a root of trust, it is not easy to detect kernel rootkits which can intercept and modify communications at the interfaces between operating system components. To provide such a monitor isolated from an operating system that can be compromised, most existing solutions are based on external hardware. Unlike those solutions, we develop a kernel introspection system based on the ARM TrustZone technology without incurring extra hardware cost, which can provide a secure memory space in isolation from the rest of the system. We particularly use a secure timer to implement an autonomous switch between secure and non-secure modes. To ensure integrity of reference, this system measured reference from vmlinux which is a kernel original image. In addition, the flexibility of monitoring block size can be configured for efficient kernel introspection system. The experimental results show that a secure kernel introspection system is provided without incurring any significant performance penalty (maximum 6% decrease in execution time compared with the normal operating system).

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.16 no.1
• /
• pp.126-142
• /
• 2016

This paper presents a wide-frequency-range, low-power transceiver with an automatic impedance-matching calibration for TV-white-space (TVWS) application. The wide-range automatic impedance matching calibration (AIMC) is proposed for the Drive Amplifier (DA) and LNA. The optimal $S_{22}$ and $S_{11}$ matching capacitances are selected in the DA and LNA, respectively. Also, the Single Pole Double Throw (SPDT) switch is integrated to share the antenna and matching network between the transmitter and receiver, thereby minimizing the systemic cost. An N-path filter is proposed to reject the large interferers in the TVWS frequency band. The current-driven mixer with a 25% duty LO generator is designed to achieve the high-gain and low-noise figures; also, the frequency synthesizer is designed to generate the wide-range LO signals, and it is used to implement the FSK modulation with a programmable loop bandwidth for multi-rate communication. The TVWS transceiver is implemented in $0.13{\mu}m$, 1-poly, 6-metal CMOS technology. The die area of the transceiver is $4mm{\times}3mm$. The power consumption levels of the transmitter and receiver are 64.35 mW and 39.8 mW, respectively, when the output-power level of the transmitter is +10 dBm at a supply voltage of 3.3 V. The phase noise of the PLL output at Band 2 is -128.3 dBc/Hz with a 1 MHz offset.

• Asia pacific journal of information systems
• /
• v.17 no.2
• /
• pp.29-47
• /
• 2007

Owing to the rapid growth of using the Internet, not only click-and-mortar companies but also brick-and-mortar ones have been expanding their distribution channels into online, Moreover, since online channels are more attractive than offline ones in control and maintenance, switching customers into online ones is emerged as one of very important managerial issues in a view of reduction of cost as well as expansion of services. However, the switched customers should be faced by uncertainties which could not have been experienced in offline. Specifically, in online channels, buyers and sellers are separated temporally and spacially and there are always so many kinds of threat for security as well as not enough systems and conventions for them yet. Therefore, trust has been considered as one of the most critical mechanisms for resolution of such uncertainties in online transactions. However, it is not easy to build and maintain the relationships in online since most of them are virtual and indirect generally. Therefore, in order to switch offline customers into online ones, it is very important to make strategies based on identification of the relationship between online transaction and offline trust which has been built in offline business. Generally offline trust, which has been built independent of online, could not include trust for online-dependent activities such as payment security during or after transactions, while most of online trust include it. Therefore, a customer with high offline trust does not always perceive high security and assure safe transactions. Accordingly, while online trust, where technical capabilities for online security is one of main bases, includes control trust implicitly or explicitly, offline trust does not. However. in spite of such clear discrimination and independence between offline trust and perceived security, there can be the significant dependency between these two beliefs. The customers with high offline trust believe that the company would do some activities for online security for customers' safe transactions since it has been believed of doing well for customers' trust. Theoretically, users' perception of security is interpreted as a kind of control trus, which is trust for company's technical control capacities in order to resolve technical uncertainties in online. Therefore, the relationship between two beliefs can be considered as transference from offline trust to another type trust. that is, control trust. The objective of this study is to analyze the effect of offline trust on online transaction uses mediated by perceived security. For this purpose, we suggest a research model based on technology acceptance model (TAM). Reuse intention is adopted as a dependent variable and TAM is modified by adding perceived risk (PR) as well as two beliefs of using Internet banking, perceived usefulness (PU) and perceived ease of use (PEOU). Moreover, perceive security (PS) is adopted as an external variable for PR and PU, while offline trust (OT) is an antecedent of PS. For an empirical test, sampling from 108 visitors to the banks in Daegu, Korea, we analyze our model by partial least square (PLS) approach. In result, our model is shown to explain 51.4% of the variance in reuse intention and all hypothesis are supported statistically. A theoretical implication of this study is to identify a role of PS between offline trust and reuse intention of using online transaction services. According to our result, PS can be considered as a mediation variable for bridging between two different concepts: trust that explains social aspects of customers and companies, and TAM that explains customers' reuse intention.

• Quality Improvement in Health Care
• /
• v.9 no.2
• /
• pp.210-228
• /
• 2002

Background: The purpose of this research was to examine the fall incidence rate and its related factors of fall in inpatients. Methods: The data were collected from the 138 fall incident reports in one tertiary hospital in Seoul from April 1st 1999 to September 30th 2001. The Fall Incident Report Form was originally developed based on that of Massachusetts General Hospital revised in 1995. And this was modified for this survey by the collaborating work of QI team including researcher and department of nursing service of this particular hospital. The contents of Fall Incident Form were general characteristics of patient. factors related to fall. types and places of fall. circumstances, nursing interventions. and outcome. Results: 1) The incidence rate of fall was 0.08% of total discharged patients and 0.081 per 1000 patient-day. This incidence rate is much lower than that of several hospitals in USA. This finding might result from the different incidence report system of each hospital. 2) The characteristics of fall-prone patient were found as follows. They were mostly over 60 years old, in alert mental status, ambulatory with some assistance, and dependent on ambulatory device. The types of diseases related high incidence rate were cerebrovascular disease(3.2), hypertension(1.6), cardiovascular disease(1.4), diabetes(1.3) and liver disease(0.6). 3) The majority of fall events usually occurred m bed. bedside(walking or standing) and bathroom in patient room. Usually they were up on their own when they fell. And there were more falls of elderly occurred during night time than day or evening. 4) 63.8% of fall events resulted in physical injuries such as fracture and usually the patients had diagnostic procedures and some treatment(ex. suture) which caused additional cost to the patients and their families. 5) The found risk factors of fall were drugs(antihypertensive drug, diuretics) and environmental factors like too high bed height, long distance of bedside table and lamp switch, and slippery tile of bathroom floor. Conclusion: Considering these results, every medical and nursing staff should be aware of the risk factors of patients in hospital, and should intervene more actively the preventive managements, specially for the elderly patients during night. Therefore, it is recommended that the development of Fall Prevention Programs based on these results.

• Journal of Digital Convergence
• /
• v.15 no.7
• /
• pp.169-180
• /
• 2017

China's mobile communication market has been growing quantitatively and qualitatively since 2000. Currently, it has secured 1.27 billion mobile subscribers and many of the Korean companies try to enter the Chinese market and cooperation with companies in China is being held. Thus understanding of the Chinese markets is the key to better prepare for future international competition. This study is to identify factors affecting switching intentions and behaviors for Chinese mobile subscribers to other mobile service providers by the PPM and it is to derive correlations between strategies of mobile service providers and users' switching intention by the groups classified by ARPU. We conducted a survey targeting 270 Chinese mobile users and analyze it by using Smart PLS 2.0. In conclusion, push effects have positive influence on intention to switching and relational switching cost among mooring effect have significantly negative influence on intention to switching In particular, intention to switching depending on the groups classified by a level of their ARPU have been shown as significantly different. This study will extend theoretical range of PPM theory in explaining users' switching behaviors and contribute to establish strategies to enter the chinese market.