• Journal of the Korean Society for Precision Engineering
• /
• v.30 no.10
• /
• pp.1023-1029
• /
• 2013

Water running animals such as basilisk lizards have an advantage of high-speed movement and high power efficiency on water; so researchers in robotic fields have been interested in the water running locomotion. This paper presents prototype-design and experimental study on the fourand six-legged water running robot. Based on the previously proposed quadruped water running robot, we assemble a hexapedal water running robot. The legs of the water running robot are designed based on four-bar parallel link for repeated motion along to pre-defined path. Stability performance of the quadruped and hexapedal water running robot are investigated by experiments on rolling criterion. As a result, hexapedal robot performs better stability than quadruped robot. Based on the hexapedal robot design, we are planning to optimize the position of legs and operating frequency.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.3 s.96
• /
• pp.174-179
• /
• 1999

A binary parallel robot manipulator uses actuators which have only two stable states and is structure is variable geometry truss. As a result, it has a finite number of states and fault tolerant mechanism because of kinematic redundancy. This kind of robot manipulator has the following advantages compared to a traditional one. Feedback control is not required, task repeatability can be very high, and finite state actuators are generally inexpensive. Because the number of states of a binary robot manipulator grows exponentially with the number of actuators, it is very difficult to solve an inverse kinematic problem. The goal of this paper is to develop an efficient algorithm to solve an inverse kinematic problem when the number of actuators are too much or the target position is located outside of workspace. The backbone curve is generated optimally by considering the curvature of the robot manipulator configuration and length of link. Then, the robot manipulator is fitted along the backbone curve with some criteria.

• Journal of Microbiology and Biotechnology
• /
• v.33 no.11
• /
• pp.1495-1505
• /
• 2023

The western honeybee Apis mellifera L., a vital crop pollinator and producer of honey and royal jelly, faces numerous threats including diseases, chemicals, and mite infestations, causing widespread concern. While extensive research has explored the link between gut microbiota and their hosts. However, the impact of Varroa destructor infestation remains understudied. In this study, we employed massive parallel amplicon sequencing assays to examine the diversity and structure of gut microbial communities in adult bee groups, comparing healthy (NG) and Varroa-infested (VG) samples. Additionally, we analyzed Varroa-infested hives to assess the whole body of larvae. Our results indicated a notable prevalence of the genus Bombella in larvae and the genera Gillamella, unidentified Lactobacillaceae, and Snodgrassella in adult bees. However, no statistically significant difference was observed between NG and VG. Furthermore, our PICRUSt analysis demonstrated distinct KEGG classification patterns between larval and adult bee groups, with larvae displaying a higher abundance of genes involved in cofactor and vitamin production. Notably, despite the complex nature of the honeybee bacterial community, methanogens were found to be present in low abundance in the honeybee microbiota.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.42 no.5 s.335
• /
• pp.55-62
• /
• 2005

In this paper, we propose an efficient symbol detection algorithm for space-frequency OFDM (SF-OFDM) transmit diversity scheme and present the implementation results of the SF-OFDM WLAN baseband processor with the proposed algorithm. When the number of sub-carriers in SF-OFDM scheme is small, the interference between adjacent sub-carriers may be generated. The proposed algorithm eliminates this interference in a parallel manner and obtains a considerable performance improvement over the conventional detection algorithm. The bit error rate (BER) performance of the proposed detection algorithm is evaluated by the simulation. In the case of 2 transmit and 2 receive antennas, at $BER=10^{-4}$ the proposed algorithm obtains about 3 dB gain over the conventional detection algorithm. The packet error rate (PER), link throughput, and coverage performance of the SF-OFDM WLAN with the proposed detection algorithm are also estimated. For the target throughput at $80\%$ of the peak data rate, the SF-OFDM WLAN achieves the average SNR gain of about 5.95 dB and the average coverage gain of 3.98 meter. The SF-OFDM WLAN baseband processor with the proposed algorithm was designed in a hardware description language and synthesized to gate-level circuits using 0.18um 1.8V CMOS standard cell library. With the division-free architecture, the total logic gate count for the processor is 945K. The real-time operation is verified and evaluated using a FPGA test system.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.46 no.3
• /
• pp.96-106
• /
• 2009

Extending the scale of the distributed processing in a single Ethernet cluster is physically restricted by maximum ports per switch. This paper presents an implementation of MPI-based multicluster consisting of multiple Ethernet switches for extending the scale of distributed processing, and a asymptotical analysis for communication overhead through execution-time analysis model. To determine an optimum task partitioning, we analyzed the processing time for various partitioning schemes, and AAP(accumulator array partitioning) scheme was finally chosen to minimize the overall communication overhead. The scope of data partitioned in AAP was modified to fit for incremented nodes, and suitable load balancing algorithm was implemented. We tried to alleviate the communication overhead through exploiting the pipelined broadcast and flat-tree based result gathering, and overlapping of the communication and the computation time. We used the linear pipeline broadcast to reduce the communication overhead in intercluster which is interconnected by a single link. Experimental results shows nearly linear speedup by the proposed parallel distributed GHT implemented on MPI-based Ethernet multicluster with four 100Mbps Ethernet switches and up to 128 nodes of Pentium PC.

• Journal of KIISE:Information Networking
• /
• v.34 no.3
• /
• pp.226-238
• /
• 2007

In this paper, we present a novel fully distributed topology control protocol that can construct the multiple-ring topology of Minimal Connected Dominating Set (MCDS) as the transport backbone for mobile ad hoc networks. It makes a topology from the minimal nodes that are chosen from all the nodes, and the constructed topology is comprised of the minimal physical links while preserving connectivity. This topology reduces the interference. The all nodes work as the nodes of the distributed parallel Boltzmann machine, of which the objective function is consisted of two Boltzmann factors: the link degree and the connection domination degree. To define these Boltzmann factors, we extend the Connected Dominating Set into a fuzzy set, and also define the fuzzy set of nodes by which the multiple-ring topology can be constructed. To construct the transport backbone of the mobile ad hoc network, the proposed protocol chooses the nodes that are the strong members of these two fuzzy sets as the clusterheads. We also ran simulations to provide the quantitative comparison against the related works in terms of the packet loss rate and the energy consumption rate. As a result, we show that the network that is constructed by the proposed protocol has far better than the other ones with respect to the packet loss rate and the energy consumption rate.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.44 no.2
• /
• pp.19-24
• /
• 2007

With recent advancement of high-speed, multi-gigabit data transmission capabilities, serial links have been more widely adopted in industry than parallel links. Since the parallel link design forces its transmitter to transmit both the data and the clock to the receiver at the same time, it leads to hardware's intricacy during high-speed data transmission, large power consumption, and high cost. Meanwhile, the serial links allows the transmitter to transmit data only with no synchronized clock information. For the purpose, clock and data recovery circuit becomes a very crucial key block. In this paper, a 5.4Gbps half-rate bang-bang CDR is designed for the applications of high-speed graphic DRAM interface. The CDR consists of a half-rate bang-bang phase detector, a current-mirror charge-pump, a 2nd-order loop filter, and a 4-stage differential ring-type VCO. The PD automatically retimes and demultiplexes the data, generating two 2.7Gb/s sequences. The proposed circuit is realized in 66㎚ CMOS process. With input pseudo-random bit sequences (PRBS) of $2^{13}-1$, the post-layout simulations show 10psRMS clock jitter and $40ps_{p-p}$ retimed data jitter characteristics, and also the power dissipation of 80mW from a single 1.8V supply.

• Korean Journal of Occupational Health Nursing
• /
• v.14 no.1
• /
• pp.56-70
• /
• 2005

Objectives: The purpose of this study is to develop a linking model between industrial injury insurance organs and local organizations providing social welfare health services, for the activation of medical rehabilitation services for industrial injury patients. Method: Research design for this study was a multi-step research through literature review, field research, and group interviews with persons in charge, to compare local society-oriented medical rehabilitation programs. The term of researches Sep.1 ~ Nov. 30, 2004. Results: 1. Home nurses from Workers Accident Medical Corporation have been taken to be adequate to case managers, who link industrial accident insurance institutions to local society services for the activation of medical rehabilitation services for industrial injury patients. They have been chosen for case managers because they have richer understanding and experiences of objects of industrial accidents than any other specialists, and because they have proved to be able to provide direct home services as a specialist. We have established the center for case management affairs within the workers accident general hospital, organized the committee for case management with doctors in charge, doctors in rehabilitation, rehabilitation consultants, social welfare workers, physical therapists, and nurses, determined objects of case managements from those of long-term recuperation, and constructed a course of case management containing from case management plans to evaluation. 2. We have made files of community resources, and organized the council of industrial accident administration to have it in charge of the adjustment and linking of services in case management affairs. 3. Because there are inequality of community resources between areas, differences in experiences in and bases for linking, and disparity of core organizations with active linking in the system of linking between public and civil sectors, we have taken a system of linking between parallel organs to be the core. In our linking model, workers accident general hospital, hospitals designated for industrial injury, and rehabilitation hospitals are linked in parallel, inadequate long-term recuperation managers are trusted to an workers accident medical corporations through examination by the examination committee in Korea Labor Welfare Corporation, and are dealt with by the committee for case management. Of the hospitals designated for industrial accidents, those running a home caring center provide home caring services for the handicapped at home from industrial injury. 4. Workers Accident Medical Corporation take part in medical rehabilitation, and Korea Labor Welfare Corporation in vocational/social rehabilitation. Furthermore, in the model, the latter should construct a system for job opportunities through Internet portals and provide cyber vocational consultation and introduction. Conclusion: Improvement of systems is needed to apply the linking model to practical affairs. Because this model is centered for practical affairs, it should be put under the analysis of effects, and evaluation of its adequacy to practical application, and its effects and efficiency through experimental running in the 8 workers accident general hospital in Korea.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.12
• /
• pp.31-39
• /
• 2012

In this paper, we propose a microprocessor-based automatic voltage regulator(AVR) to reduce consumers' electric energy consumption and to help controlling peak demanding power. Hybrid Switching Automatic Voltage Regulator (HS-AVR) consist of a toroidal core, several tap control switches, display and command control parts. The coil forms an autotransformer which has a serial main winding and four parallel auxiliary windings. It controls the output voltage by changing the combination of the coils and the switches. Relays are adopted as the link switches of the coils to minimize the loss. To make connecting and disconnecting time accurate, relays of the circuit have parallel TRIACs. A software phase locked loop(PLL) has been used to synchronize the timings of the switches to the voltage waveform. The software PLL informs the input voltage zero-crossing and positive/negative peak timing. The traditional voltage transformers and AVRs have a disadvantage of having a large mandatory capacity to accommodate maximum inrush current to avoid the switch contact damage. But we propose a suitable AVR for every purpose in smart grid with reduced size and increased efficiency.

• The Journal of the Korea Contents Association
• /
• v.8 no.12
• /
• pp.236-245
• /
• 2008

The cancer patient who leads Bone scan and the PET study from in the nuclear medical study what is enforced with the link of early detection and the time which spreads, it will be able to accomplish a positive treatment with the data which presumes that time it researches a degree as cancer discovery initially and only difference of final period the bay it knows. The patient who receives a cancer decision it will be able to accomplish the necessary defense it will be able to delay the time in order, the maximum control the possibility of doing will be becomes the judgement. Cancer decision to initially the nuclear study and treatment it will be in parallel with effort and the investment which are constant and the schedule hour will elapse and to after difficulty some the case which comes to be negligent will be frequent and it will appear with him there to be a possibility of knowing, it will be caused by and the transfer of the cancer sell will be activity. It has a treatment objective and are to each medical treatment agency against and the medical treatment agency worker it will be able to overlook is not the portion is the private plan which needs a more positive disposal, it does.