마이크로프로세서를 利用한 디지탈필터의 特性 改善

郭勳星,李斗秀,金定德 全北大學校 1980 論文集 Vol.22 No.-

This paper introduces a technique for implementing a second order recursive digital filter. The realization is based on the residue number system and sequentially multiplexing two look-up tables which are used for the operations of addition and multiplication. The data rate of the filter implemented with microprocessor is improved under some assumption.

Pade 近似化 方法에 依한 필터의 設計

郭勳星,金英百 全北大學校 1981 論文集 Vol.23 No.-

A rational approximation procedure for digital filter design is presented in this paper. More specially, an explicit expression for the designed filter transfer function can be obtained once a rational approximation for the analytic part of the Fourier series expansion of the desired filter characteristic is determined. To demonstrate the efficiency of this technique, we derive a two-sided Pade´ approximation from the one-sided Pade´ approximant. Two examples are given to illustrate this design procedure.

Lutembacher 증후군 환자 증례 보고

김성범,서정주,곽철훈,김상민,이보라,민선경,황은구,김용인,조욱현,최석구 인제대학교 2008 仁濟醫學 Vol.29 No.-

Lutembacher's syndrome is rare combination of mitral stenosis (MS) and atrial septal defect (ASD). The hemodynamic interplay between the MS and ASD leads to wide variation of clinical presentation. Here we describe a 43-year-old female with Lutembacher's syndrome and tricuspid regurgitation with pulmonary hypertension, who underwent direct closure of ASD and tricuspid valvuloplasty successfully. We also reviewed other literatures in an effort to increase awareness of this condition.

새로운 무기 응집제 개발에 따른 특성

최성우,우성훈,윤철종,곽명화,서향미,박승조 동아대학교 환경문제연구소 2000 硏究報告 Vol.23 No.1

This study has carried out the coagulation tests for tannery wastewater including high-level suspended solids and organic matters to determine the optimum pH and coagulant dosage and to characterize several coagulants for coagulation. In case of optimum pH range test, we know that multi-coagulants are not only cost-effective but also applicable from acidic pH range to alkaline pH range widely, while single-coagulant are useful in limited pH range. Removal efficiency for using of the multi-coagulants appeared more efficient than that of single-coagulant. Especially, sulfates(alum-ferric sulfate : AFS & alum-magnesium sulfate : AMS) are more effective than chlorides (alum-ferric chloride : AFC & alum-magnesium chloride AMC). In comparison of residual turbidity related to settling time between alum and alum-ferric sulfate-magnesium sulfate(AFM), it took to 40 minutes using of alum but 5 minutes using of alum-ferric sulfate-magnesium sulfate(AFM) until constant residual turbidity are reached.

Spontaneous Renal Forniceal Rupture caused by a Calculus in an Anuric Patient receiving Long-Term Hemodialysis

Kyong Min Kwak,Seong Hoon Kim,Sang Hyeon Choi,Sang Kon Lee,Won Ki Lee,Ji Won Ryu,Jong Woo Yoon,JaRyong Koo,Myung Jin Choi 조선대학교 의학연구원 2014 The Medical Journal of Chosun University Vol.39 No.4

A 63-year-old woman with a history of nephrolithiasis and long-term hemodialysis (HD) presented with abdominal pain. Abdominal computed tomography (CT) showed urinoma induced by renal forniceal rupture, and three causative calculi. No active stone growth or new stones were observed when compared with previous CT, however, fragmentation and migration of an existing stone was observed. After ureteroscopic lithotripsy and stenting with a double-J catheter, the patient made a full recovery. To the best of our knowledge, this is the first case of spontaneous renal forniceal rupture in an anuric HD patient caused by calculi. Renal forniceal rupture can occur, even in anuric HD patients.

망막 광응고 창상에 대한 Basic Fibroblast Growth Factor의 효과

곽노훈(No Hoon Kwak),유진성(Jin Seong Yoo),허원(Warne Huh),천명훈(Myeong Hoon Cuhn) 대한안과학회 2000 대한안과학회지 Vol.41 No.8

Antibiotic Resistant Microbial Contamination (Enterobacter cloacae) Derived from Egg Yolk and Frozen Semen Extender in Porcine In Vitro Fertilized Embryos

Kwak, Seong-Song,Jeong, Se-Heon,Jang, Seung-Hoon,Jeon, Yu-Byeol,Nam, Young-Hee,Biswas, Dibyendu,Lee, Wan-Kyu,Hyun, Sang-Hwan 韓國受精卵移植學會 2010 한국동물생명공학회지 Vol.25 No.4

The present study was to investigate the source of contamination during semen processing for in vitro uses. In the present study, frozen semen was prepared from liquid semen in our laboratory for in vitro fertilization (IVF) experiments due to lack of fresh semen. Antibiotics were added in the frozen semen extender (kanamycin and gentamicin) and in vitro culture (IVC) medium (gentamicin) for further inhibiting growth of microorganisms. Nevertheless, proliferations of microorganisms were observed in IVC culture drop during culturing of IVF embryos using frozen semen. Randomly 3 samples were taken from the liquid semen, frozen semen and egg yolk. Contaminated IVC medium, frozen-thawed semen, liquid semen and egg yolk were cultured in de Man, Rogosa and Sharpe (MRS) agar medium. Whitish colonies were detected in contaminated IVC drop, frozen-thawed semen samples and egg yolk but no colonies were formed in liquid semen samples. Gram-negative and rod-shaped identical bacteria were found in both frozen-thawed semen sample and contaminated IVC drop and egg yolk samples. Enterobacter cloacae were confirmed by API 20E kit according to manufacturer's instruction with identification value (% ID) 94.3% and T index 0.88. Antibiotic susceptibility tests were done according to Clinical and Laboratory Standards Institute (CLSI) by using ampicillin, amikacin, cephalothin, gentamicin, kanamycin, tetracycline, oxytetracycline, sulfamethoxazole trimethoprim, norfloxacin and ciprofloxacin test. Among them Enterobacter cloacae were resistant to ampicillin, amikacin, cephalothin, gentamicin, kanamycin but susceptible to tetracycline, oxytetracycline, sulfamethoxazole trimethoprim, norfloxacin and ciprofloxacin. From these findings it could be suggested that this contamination sources might be from egg yolk.

Surgical Results of Selective Median Neurotomy for Wrist and Finger Spasticity

Kwak, Kyung-Woo,Kim, Min-Su,Chang, Chul-Hoon,Kim, Sang-Woo,Kim, Seong-Ho The Korean Neurosurgical Society 2011 Journal of Korean neurosurgical society Vol.50 No.2

Objective : This study aimed to evaluate the surgical outcomes of selective median neurotomy (SMN) for spastic wrist and fingers. Methods : We studied 22 patients with wrist and finger spasticity refractory to optimal oral medication and physical therapy. The authors evaluated spasticity of the wrist and finger muscles by comparing preoperative states with postoperative states using the modified Ashworth scale (MAS). We checked patients for changes in pain according to the visual analog scale (VAS) and degree of satisfaction based on the VAS. Results : The preoperative mean MAS score was $3.27{\pm}0.46$ ($mean{\pm}SD$), and mean MAS scores at 3, 6, and 12 months after surgery were $1.82{\pm}0.5$, $1.73{\pm}0.7$, and $1.77{\pm}0.81$ ($mean{\pm}SD$), respectively. On the last follow-up visit, the mean MAS score measured $1.64{\pm}0.9$ ($mean{\pm}SD$). Wrist and finger spasticity was significantly decreased at 3, 6, and 12 months after the operation (p<0.01). The preoperative mean pain VAS score was $5.85{\pm}1.07$ ($mean{\pm}SD$), and the mean pain VAS score on the last follow-up visit after surgery was $2.28{\pm}1.8$ ($mean{\pm}SD$). Compared with the preoperative mean pain VAS score, postoperative mean pain VAS score was decreased significantly (p<0.01). On the basis of a VAS ranging from 0 to 100, the mean degree of patient satisfaction was $64.09{\pm}15.93$ ($mean{\pm}SD$, range 30-90). Conclusion : The authors propose SMN as a possible effective procedure in achieving useful, long-lasting tone and in gaining voluntary movements in spastic wrists and fingers with low morbidity rates.

Efficacy of argon plasma coagulation in the treatment of radiation-induced hemorrhagic gastroduodenal vascular ectasia

Kwak, Hee-Won,Lee, Woo Jin,Woo, Sang Myung,Kim, Bo Hyun,Park, Joong-Won,Kim, Chang-Min,Kim, Tae Hyun,Han, Sung-Sik,Kim, Seong Hoon,Park, Sang-Jae,Kook, Myeong Cherl Informa Healthcare 2014 Scandinavian journal of gastroenterology Vol.49 No.2

<P><B><I>Objective.</I></B> Radiation-induced hemorrhagic gastroduodenal vascular ectasia (GDVE) is rare but difficult to manage. Argon plasma coagulation (APC) has not yet been evaluated in the treatment of radiation-induced hemorrhagic GDVE. The efficacy of APC in patients with radiation-induced hemorrhagic GDVE has been investigated in this article. <B><I>Material and methods.</I></B> Eighteen patients with upper gastrointestinal (GI) bleeding caused by radiation-induced GDVE, including 13 with hepatocellular carcinoma, 3 with pancreatic cancer, and 2 with cholangiocarcinoma, were treated with APC. The efficacy of APC was retrospectively evaluated, based on cessation of macroscopic GI bleeding, resolution or stabilization of anemia and transfusion dependence, endoscopic ablation of almost all vascular lesions, complications, and recurrence. <B><I>Results.</I></B> Mean patient age was 59 years (range 42-80 years). The median time from radiation to GDVE diagnosis was 4.6 months (range 3.3-21.5 months). The median number of APC sessions per patient was 2.4 (range 1-4). All 18 patients showed an endoscopic response to APC treatment, with sustained increases in mean hemoglobin level, from 6.6 g/dL (range 2.9-9.5g/dL) to 9.7 g/dL (range 7.1-12.7 g/dL) (<I>p</I> < 0.001), and decreased dependence on transfusion, from 9.1 (range 0-30) to 4.1 (range 0-15) units of packed red blood cells per patient (<I>p</I> = 0.038) after last endoscopic eradication by APC treatment. There were no major procedure-related adverse events or deaths. At a median follow up of 4.7 months (range 0.6-24.5 months), none of the patients experienced recurrence of GDVE. <B><I>Conclusions.</I></B> APC showed short-term effectiveness and safety in the treatment of radiation-induced hemorrhagic GDVE.</P>

The Prevalence and Characteristics of Depression in Work-related Musculoskeletal Disease

Kwak, Jehwan,Kim, Hyung Kuk,Kim, Taikon,Jang, Seong-Ho,Lee, Kyu Hoon,Kim, Mi Jung,Park, Si-Bog,Han, Seung Hoon Korean Academy of Rehabilitation Medicine 2012 Annals of Rehabilitation Medicine Vol.36 No.6

<P><B>Objective</B></P><P>To reveal the relationship between depression and WMSD.</P><P><B>Method</B></P><P>Five physiatrists participated in the workplace musculoskeletal survey and diagnosed 724 office workers with WMSD by performing detailed history taking and physical examination. All subjects were asked to answer the Korean version of the Beck depressive inventory (K-BDI), and to express their pain according to the visual analogue scale (VAS) score. We categorized the subjects into 4 groups, myofascial pain syndrome (MPS), herniated intervertebral disk (HIVD), tenosynovitis, and others, and investigated the prevalence of depression in desk workers and relationship between WMSD and depression, and we compared pain intensity between the depression and non-depression groups. Correlation analysis was carried out between K-BDI and VAS scores in each group.</P><P><B>Results</B></P><P>The mean K-BDI score were 8.7±6.68. The prevalence of depression was higher in females than in male, and there was no relationship between age and depression. There was a significant connection between HIVD and depression (p<0.05). However, the other groups did not have significant connection to depression. The VAS score (5.02) of the depression group was significantly higher than that (4.10) of the non-depression group. In addition, there was a significant difference of VAS scores between the depression group and non-depression group in each disease group.</P><P><B>Conclusion</B></P><P>The mean VAS score of the depression group in WMSD was significantly higher than in the non-depression group. The correlation between BDI and VAS scores in the subjects was present, and the highest was in the HIVD group.</P>