Earticle

무선 센서 네트워크에서 사용되는 센서 노드는 확장성, 이동성, 휴대성 등을 위해서 작은 크기의 디바이스 형태로 제작되고 있다. 이러한 센서 노드의 소형화는 가용 전지의 양, 메모리 크기, 처리속도를 제한하고 무선센서 네트워 크의 수명을 단축시킨다. 무선센서 네트워크에서는 수명을 늘리는 것이 매우 중요하다. 하지만 센서노드는 데이터 전송 시 가장 많은 전력이 소모 된다. 데이터 압축 기법은 이를 해결하기 위한 대표적인 방법 중 하나이다. 따라서 본 논문에서는 패킷손실 확률에 따라서 압축 기법의 이득을 분석하였다. 데이터 압축 기법은 최소한의 전송량으로 데이터를 줄이므로 전송에 따른 에너지 소모를 최소화하여 무선센서 네트워크에서의 수명을 증가시킬 뿐만 아니라 센서노드 시스템의 처리량을 최대화 하고 작업의 수행시간을 최소화한다. 본 논문의 실험에서 패킷 전송 시 데이터 압축을 통해 전송하였을 경우 패킷손실 확률과 데이터의 전송량에 따라서 성능에 미치는 영향을 실험하고, 데이터 압축 전과 비교하였다. 실험결과, 패킷손실 확률이 40%일 경우 최대 68ms정도의 응답지연시간이 감소되고 처리량 은 30%가 증가된다. 그러므로 압축 기법을 사용하였을 때 압축 기법을 사용하기 전보다 응답 지연시간은 더욱 감 소하고 처리량은 증가 시킨다. 또한, 패킷손실 확률이 증가할수록 응답시간과 처리량측면에서 얻는 이득은 더욱 향 상된다.

Size of sensor nodes which used in wireless sensor networks has been decreasing for its scalability, mobility, and portability. This miniaturization of sensor node limits resources such as limited battery power, processing speed, and memory space. In addition, limited resources reduce the lifetime of wireless sensor networks. The advance of the lifetime is a very important part considered in wireless sensor networks. However, most of the power consuming tasks are data transmission. Data compression is one field of studies to resolve this problem. Thus, we analysis the benefit of compression techniques according to packet loss probability. Compression techniques improves the performance and extends the 논문투고일자: 2009. 11. 2 심사일자: 2009. 11. 20 게재확정일자: 2009. 12. 11 【논 문 】한국차세대컴퓨팅학회 논문지 2009년 12월 57 life time of wireless sensor networks(WSNs). In our experiment, we evaluate the impact of data compression depending on packet loss probability and data size. Experimental results describe that compared to baseline(no compression), latency is decreased by 68ms and throughput is increased by 30% in case of packet loss probability of 40%. Therefore, applying compression techniques can reduce latency and increase throughput than baseline. In addition, as the packet loss probability is increased, we can achieve more enhancement in the perspective of latency and throughput by using compression techniques.

기계의 무게를 대폭 줄이는 것을 목적으로 복합재료에 대해서 많은 연구를 진행하고 있다. 본 연구 에서 탄소 섬유 강화 플라스틱과 알루미늄 폼으로 조합해서 만든 샌드위치에 대해서 압축 시뮬레이션 해 석을 하였다. 또한 탄소 섬유 강화 플라스틱의 섬유의 배열방식은 [0/90/90/0]이다. 시뮬레이션 해석 방법 은 ANSYS를 이용하여 실제와 같은 경계조건을 주고 유한요소해석을 진행하였다. 시편을 압축하는 동안 에 탄소 섬유 강화 플라스틱과 알루미늄 폼이 그 접착력보다 크게 발생되어 떨어지는 형상이 일어났다. 또한 2438.3MPa의 최대 등가응력이 발생된 것을 확인하였다. 본 연구에서 나온 해석결과는 안전설계 및 복합재료의 개발에 필요한 자료를 제공할 수 있을 것으로 사료된다.

This study investigates the mechanical behavior at the compression of bonded aluminum foam. Four kinds of specimen thicknesses are 25, 50, 75 and 100mm. These aluminum foams are compressed with the speed of 5mm/min. The reaction forces in cases of 25, 50, 75 and 100mm are 2510, 5080, 7700 and 10400N respectively. The equivalent stresses are 0.96, 1.00, 1.02 and 1.03MPa respectively. These analysis results are verified by comparing with the experimental results. The results of this study can be contributed to the safe design of structure.

H.264/AVC is an authoritative international video coding standard, which shows improved code and efficiency than the existing video standards. Above all, inter prediction techniques using the motion vectors of H.264/AVC did play a big role in video compression developing. After that, HEVC came out further development of the H.264/AVC. Especially, seems a lot of effort to reduce the amount of motion information, we get Inspired by the benefits, algorithm using Huffman coding method is proposed to reduce compressive of motion information. experimental results based on JM18.2 reference software was successful in bringing the compression ratio rises.

The existing rock blasting & expansive demolition agents methods that applied to small and midium sizes of rocks & concrete demolition have caused diverse problems such as dirty scattering, noise, tremor, public complaints, environment destruction, waste treatment, and so this researcher examined the possibility of rock demolition by using the expansibility of dried woods which are environment friendly and high in recycling rate and economical to solve such problems. Maximum swelling pressure of the test specimen and the tensile strength of rock were compared and it showed that φ55 Ash and Oak exceeded the range of average tensile strength of the target rock, and in the test specimen hydrating sodium hydroxide aqueous solution appeared to have exceeded the average tensile strength of the rock in the whole test specimen excepting Maple. When compared with the swelling pressure of expansive demolition agents, the test specimen that containing tap water appeared to be inferior to the swelling pressure of demolition agents, but in test specimen containing hydrating sodium hydroxide aqueous solution, φ55 Ash & Oak and φ50 Ash appeared to be similar or superior to the swelling pressure of demolition agents. Provided the swelling pressure of test specimen should be similar to the strength of rock or the swelling pressure of demolition agents, as a realistic demolition requires very high swelling(expansion), Ash seems to be able to act as a demolition material for boulder blasting in demolishing rock.

Lymphocele is a complication of pelvic surgery that infrequently leads to compressive neuropathy. We present a case of compressive obturator neuropathy resulting from lymphocele development after pelvic surgery. Electrodiagnostic studies revealed severe axonal disruption in the left obturator nerve, which is associated with poor functional recovery. This case underscores the role of electrodiagnostic testing in the diagnosis and rehabilitation of patients experiencing lower limb weakness following gynecological pelvic surgery.

Objective: To compare the immediate recovery effects of cold compression (CC) and ischemic preconditioning with ice (IPCice) on muscle recovery, this study was conducted.Methods: Athletes were randomly assigned to CC (n=12), IPCice (n=12), or control (n=12) groups. All participants completed a fatigue-inducing jump rope protocol targeting the gastrocnemius prior to recovery interventions. CC involved 20 minutes of alternating pressure (25?75 mmHg) on the gastrocnemius muscles. IPCice involved thigh cuffs inflated to 200 mmHg (2 minutes on/off cycles for 20 minutes) with manual ice application. Thirty-six amateur mixed martial arts (MMA) athletes. Muscle pain, congestion, strength, creatine kinase, muscle stiffness, perfusion, pressure pain threshold, reactive strength index, and total quality recovery were assessed at rest, post-exercise, post-treatment, and 48 hours later.Results: Post-treatment, CC significantly improved perfusion (p<0.001) and reduced muscle soreness in both legs compared to IPCice and control (p≤0.02). CC also resulted in significantly higher PPT values (p≤0.006). Benefits on some variables remained at 48 hours.Conclusion: Both modalities enhanced recovery following fatiguing exercise; however, CC demonstrated superior effectiveness in attenuating fatigue-related impairments, particularly in perfusion, soreness, and muscle function, highlighting its practical advantage over IPCice for MMA athletes.

Driven by edge computing, how to efficiently deploy the meta-learner LSTM in the resource constrained FPGA terminal equipment has become a big problem. This paper proposes a compression strategy based on LSTM meta-learning model, which combined the structured pruning of the weight matrix and the mixed precision quantization. The weight matrix was pruned into a sparse matrix, then the weight was quantified to reduce resource consumption. Finally, a LSTM meta-learning accelerator was designed based on the idea of hardware?software cooperation. Experiments show that compared with mainstream hardware platforms, the proposed accelerator achieves at least 50.14 times increase in energy efficiency.

Popliteal entrapment syndrome caused by isolated popliteus muscle enlargement is very rare, although its occurrence has been reported after discrete trauma. However, popliteal artery stenosis with combined peroneal and proximal tibial neuropathy caused by popliteus muscle enlargement without preceding trauma has not been reported. A 57-year-old man presented with a tingling sensation and pain in his left calf. He had no previous history of an injury. The symptoms were similar to those of lumbosacral radiculopathy. Calf pain became worse despite treatment, and the inability to flex his toes progressed. Computed tomography angiography and magnetic resonance imaging of the lower extremity showed popliteal artery stenosis caused by popliteus muscle enlargement and surrounding edema. An electrodiagnostic study confirmed combined peroneal and proximal tibial neuropathy at the popliteal fossa. Urgent surgical decompression was performed because of the progressive neurologic deficit and increasing neuropathic pain. The calf pain disappeared immediately after surgery, and he was discharged after the neurologic functions improved.

Objective To investigate the effects of trigger point injection with or without ischemic compression in treatment of myofascial trigger points in the upper trapezius muscle.Methods Sixty patients with active myofascial trigger points in upper trapezius muscle were randomly divided into three groups: group 1 (n=20) received only trigger point injections, group 2 (n=20) received trigger point injections with 30 seconds of ischemic compression, and group 3 (n=20) received trigger point injections with 60 seconds of ischemic compression. The visual analogue scale, pressure pain threshold, and range of motion of the neck were assessed before treatment, immediately after treatment, and 1 week after treatment. Korean Neck Disability Indexes were assessed before treatment and 1 week after treatment.Results We found a significant improvement in all assessment parameters (p<0.05) in all groups. But, receiving trigger point injections with ischemic compression group showed significant improvement as compared with the receiving only trigger point injections group. And no significant differences between receiving 30 seconds of ischemic compression group and 60 seconds of ischemic compression group.Conclusion This study demonstrated the effectiveness of ischemic compression for myofascial trigger point. Trigger point injections combined with ischemic compression shows better effects on treatment of myofascial trigger points in the upper trapezius muscle than the only trigger point injections therapy. But the duration of ischemic compression did not affect treatment of myofascial trigger point.

Background Low back pain caused lumbopelvic instability and the passive and active stabilizing system and neural control subsystem control lumbopelvic stability. Purpose The aim of this study was to identify three-dimensional motions of pelvic and trunk during one leg standing applying the pelvic compression belt. Study design One group pre- and post-test design. Methods Twenty three healthy participants volunteered for this study. For the pre-test, their pelvic and trunk motions were measured during one leg standing in stance of the dominant side using equipment without application of pelvic compression belt. The participants wore pelvic compression belt for 20 minutes on a daily basis for a week in standing position to get used to application of pelvic compression belt. After one week training, the participants were measured during one leg standing in stance of the dominant side using equipment with application of pelvic compression belt for the post-test. The three-dimensional motion analysis system was used to measure the motion of anterior-posterior tilt, medial-lateral tilt, and rotation of the pelvis, as well as anterior-posterior flexion, lateral flexion, and rotation of the trunk during one leg standing. Results The motion of anterior-posterior tilt, medial-lateral tilt, and rotation of the pelvis were significantly decreased in the post-test than pre-test during one leg standing (p<0.05). Also the motion of anterior-posterior flexion, lateral flexion, and rotation of the trunk were significantly decreased in the post-test than pre-test during one leg standing (p<0.05). Effect sizes for pelvic anterior-posterior tilt, anterior-posterior flexion, lateral flexion, and rotation of the trunk were medium between pre-test and post-test during one leg standing (d=055?0.75). Conclusions This study found the motions of the pelvis and trunk were decreased by the passive support of the pelvic compression belt during one leg standing. This finding suggests that the pelvic compression belt will help to improve the stability of lumbopelvis in back pain patients with lumbopelvic instability.

ABSTRACT Background Pelvic compression belt passively stabilized the sacroiliac joint via application of a compression force, thereby having a possibility to affect hip muscle strength. Purpose We investigated the effects of pelvic compression belts on the strength of hip extensor and the electromyographic (EMG) activities of latissimus dorsi and erector spinae during isometric prone hip extension with knee extension and prone hip extension with knee flexion. Study design Comparative, repeated measures design. Methods We recruited 15 patients with sacroiliac joint pain. All performed isometric prone hip extension with knee extension with and without a pelvic compression belts at a hip extension of 10°. Strength of hip extensor were measured using a load cell, and the muscle activities of the contralateral latissimus dorsi and erector spinae muscles measured using surface EMG. Results Strength of hip extensor with a pelvic compression belts increased significantly compared to without a pelvic compression belts (p<0.001) as did the EMG activity of the contralateral latissimus dorsi (p<0.05). However, the EMG activity of the contralateral erector spinae did not change significantly (p>0.05). Conclusions We recommend using of a pelvic compression belts by sacroiliac joint pain patients increased the strength of hip extensor and muscle activity of contralateral latissimus dorsi.

Ulnar neuropathy at the wrist (UNW) is uncommon and it may result from various causes such as tumors, fracture, or overuse injuries. Also a ganglion has been reported as a rare cause of UNW. Ganglions are the most common soft tissue tumors of the hand and wrist, but their etiology remains controversial. Several studies have described associated abnormalities of the intracarpal ligaments. However, ganglions associated with triangular fibrocartilage complex (TFCC) lesions are rarely reported so far. We hereby report a case of UNW caused by a ganglion and an associated TFCC lesion.

Thyroid carcinoma is the commonest endocrinological malignancy. After papillary thyroid carcinoma (PTC), follicular thyroid carcinoma (FTC) is the second most common histological subtype. Common presentations of FTC include a solitary thyroid nodule and cervical lymphadenopathy. The incidence of individuals diagnosed with thyroid cancer showing initially distant metastatic disease ranges from 1 to 9%. Also, the incidence of solitary bone metastasis from thyroid is only 2 to 3%. We report a case of a patient with FTC whose initial presentation was low back pain and right buttock pain due to vertebral metastasis rather than the usual neck lumps or symptoms of thyroid disease.

Saphenous mononeuropathy is an uncommon neuropathy in clinical condition, which may incur from various surgical procedures, direct trauma, or entrapment, and most frequently involves at the adductor canal, or Hunter’s canal. A 17-year old female, who was majoring in ballet, visited our rehabilitation clinic for numbness in the medial aspect of the left lower leg for the previous 9 months, without weakness. The electrodiagnostic study revealed only a delayed small potential in the left saphenous nerve. MRI examination showed soft tissue swelling in the medial side of the left knee. Accordingly, we diagnosed the patient with saphenous mononeuropathy around the knee, without lumbar plexopathy or femoral neuropathy. We report a case of saphenous mononeuropathy which developed after repetitive compression on the medial side of the knee without any other iatrogenic injury, and include a review of the relevant literature.

Objective To evaluate the effect of a modified hand compression bandage in patients with a post-burn hand edema.Methods Patients were recruited from burn centers. We classified the patients into two groups: the modified hand compression bandage group comprising of 22 patients who had a modified hand compression bandage and received conventional physical therapy and the conventionally treated group, comprising of 20 patients who received only conventional physical therapy during the 4-week period post-burn. Hand circumference, hand skin thickness, and hand function were evaluated by grip strength, active range of motion (ROM), Jebsen hand function test, and visual analogue scale (VAS). These assessments were used to evaluate treatment effectiveness prior to the first treatment, 2 weeks after the first treatment, 4 weeks after the first treatment, and 4 months after the first treatment.Results As a result of repeated-measures analysis of variance on hand circumference, skin thickness, VAS, and each metacarpophalangeal joint ROM, we found significant differences that corresponded to time effect (p<0.05) and time×group (reciprocal action) effect (p<0.05). The results of grasp power, Jebsen hand function test, and each proximal interphalangeal joint ROM, show significant differences in accordance with the time effect (p<0.05), however, there was no reciprocal action effect (p>0.05).Conclusion The modified hand compression bandage will be clinically useful for the treatment of patients with post-burn hand edemas.

Purpose: This study aimed to identify the characteristics and efficacy of Intermittent Pneumatic Compression (IPC) interventions for preventing Venous Thromboembolism (VTE) in critically ill patients. Methods: The CENTRAL, Embase, OVID, CINAHL, KMbase, KoreaMed, and KoreaScience databases were searched from January 7 to 11, 2023. The search included all records from the inception of each database up to January 2023, with publication language restrictions to English and Korean. Three reviewers independently carried out the entire process, which included data search, quality assessment, and data extraction. Results: Out of 1066 articles, six Randomized Controlled Trials (RCTs) were included. One of the four studies that reported on the incidence of DVT, and one of the six studies that measured the incidence of Pulmonary Embolism (PE), found that IPC alone was effective in reducing the incidence of DVT and PE. One of the four studies that reported on VTE incidence demonstrated a significant reduction in VTE incidence with a triple intervention of IPC, anticoagulants, and elastic compression stockings compared to a combined intervention of anticoagulants and graduated compression stockings. Four studies that reported data on the incidence of bleeding reported no effect on reducing bleeding. Conclusion: Our findings suggest that IPC interventions may reduce the incidence of DVT as a preventive strategy in critically ill patients. Further RCTs are necessary to evaluate the effect of IPC interventions on DVT prevention in this patient population and to provide robust evidence for critical care nursing.

In this paper, we propose a new method for generating convolution filters of a convolutional neural network (CNN) model as linear combinations of only a few basis filters that are provided as input features. In our approach, best coefficients of the linear combinations are searched (trained) with the given input basis filters (IBFs) to reconstruct the convolution filter parameters. Since all the convolution filters can be generated by the linear combinations of the IBFs, the size of a CNN model can be compressed if the number of coefficients for the linear combinations is less than that of filter parameters. Our primary goal is to investigate the possibility of expressing filters with a small set of IBFs by linear combinations. The second goal is to compress a model so that it can be beneficial when the model is distributed and stored (particularly downloaded to mobile devices through Wi-Fi).