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The Effect of Firm Characteristics on the Relationship between Managerial Ability and Firm Performance (기업특성이 경영자능력과 경영성과의 관계에 미치는 영향)

  • Cho, Sang-Min;Yoo, Ji-Yeon
    • Management & Information Systems Review
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    • v.37 no.1
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    • pp.103-122
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    • 2018
  • This paper expands the results of previous studies indicating that manager's ability positively affects business performance to analyze whether the degree to which the role of manager's ability improves business performance appears differently according to the characteristics of enterprises. As for the characteristics of enterprises, whether enterprises correspond to enterprises with high levels of funding constraints or late movers in the market is considered. Enterprises with high levels of funding constraints greatly require managers' roles not only for efficient use of funds but also for smooth financing. Late movers require more judgments of professional managers to overcome insufficient resources held and low profitability. In the case of enterprises with corporate characteristics with high dependency on the manager, the business performance is expected to greatly vary with the ability of the manager. The empirical analysis was conducted with listed companies from 2010 to 2014, manager's ability was measured by first measuring the efficiency of the entire enterprise through data envelopment analysis (DEA) using the methodology of Demerjian et al.(2012) and removing enterprise characteristics factors thereafter. Business performance was measured by the return on industrial fixed assets. The results of the empirical analysis indicated that the degree to which manager's ability improves business performance was higher in managerial competence enhances managerial performance in enterprises with high levels of funding constraints and late movers. Business performance is considered to have been improved further in cases where manager's ability is high because investments were made more efficiently through smooth funding. In addition, in the case of late movers in relatively poor environments, business performance was improved further because high manager's ability induced efficient decision making. In this paper, we extend the precedent study that the manager's ability improves the management performance, and confirm that the manager's ability to improve the managerial performance can be different according to the situation of the company. In addition, it is meaningful to analyze empirically whether a company's managerial ability is more important. This paper expanded the results of previous studies indicating that manager's ability improves performance to identify that the degree to which manager's ability improves business performance may appear differently according to situations in which enterprises are placed. In addition, this paper is meaningful in that it empirically analyzed what enterprises require manager's ability more importantly.

Association between Dental Fear and Anxious Thoughts and Tendencies and Dental Experience of Dental Patients (치과내원 환자의 불안취약사고 경향 및 치과경험과 치과공포의 관련성)

  • Hwang, Hye-Rim;Choi, Ha-Na;Cho, Young-Sik
    • Journal of dental hygiene science
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    • v.11 no.1
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    • pp.15-21
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    • 2011
  • Introduction The aim of this study, personal trait and their dental care based on experience level of dental fear is to analyze the differences. Catastrophizing is an irrational belief that something is far worse than it actually is. Because it makes it possible to analyze patients' anxious thoughts and tendencies. Methods The Dental Fear Survey(DFS) and Anxious Thoughts and Tendencies(AT&T) were used as measuring tools, and the independent sample t-test and ANOVA were performed on the basis of the mean value of the summated scale scores and the standard deviation. On the factors to dental anxiety, the multiple regression analysis was performed. Results Demographically, the total DFS score was higher in women($25.73{\pm}8.27$) than in men. Also, AT&T was higher in women($31.01{\pm}7.05$) (p<0.05). Dental fear was intense in the group of patients who visited dental clinics only problems($25.29{\pm}8.57$) than in those regular visited($22.29{\pm}7.78$). In relation to dental experiences, the DFS score was significantly higher in children. In many cases, patients experienced therapeutic pains in children($26.40{\pm}9.54$) (p=0.004). Also in many patients, dental anxiety began to occur in adolescence(44.3%). The multiple regression analysis result, it was found that dental treatment pain and their AT&T wielded great influence upon dental fear.

Retrospective Evaluation of Discrepancies between Radiological and Pathological Size of Hepatocellular Carcinoma Masses

  • Tian, Fei;Wu, Jian-Xiong;Rong, Wei-Qi;Wang, Li-Ming;Wu, Fan;Yu, Wei-Bo;An, Song-Lin;Liu, Fa-Qiang;Feng, Li;Liu, Yun-He
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9487-9494
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    • 2014
  • Background: The size of a hepatic neoplasm is critical for staging, prognosis and selection of appropriate treatment. Our study aimed to compare the radiological size of solid hepatocellular carcinoma (HCC) masses on magnetic resonance imaging (MRI) with the pathological size in a Chinese population, and to elucidate discrepancies. Materials and Methods: A total of 178 consecutive patients diagnosed with HCC who underwent curative hepatic resection after enhanced MRI between July 2010 and October 2013 were retrospectively identified and analyzed. Pathological data of the whole removed tumors wereassessed and differences between radiological and pathological tumor size were identified. All patients were restaged using a modified Tumor-Node-Metastasis (TNM) staging system postoperatively according to the maximum diameter alteration. The lesions were classified as hypo-staged, iso-staged or hyper-staged for qualitative assessment. In the quantitative analysis, the relative pre and postoperative tumor size contrast ratio ($%{\Delta}size$) was also computed according to size intervals. In addition, the relationship between radiological and pathological tumor diameter variation and histologic grade was analyzed. Results: Pathological examination showed 85 (47.8%) patients were overestimated, 82 (46.1%) patients underestimated, while accurate measurement by MRI was found in 11 (6.2%) patients. Among the total subjects, 14 (7.9%) patients were hypo-staged and 15 (8.4%) were hyper-staged post-operatively. Accuracy of MRI for calculation and characterized staging was related to the lesion size, ranging from 83.1% to 87.4% (<2cm to ${\geq}5cm$, p=0.328) and from 62.5% to 89.1% (cT1 to cT4, p=0.006), respectively. Overall, MRI misjudged pathological size by 6.0 mm (p=0.588 ), and the greatest difference was observed in tumors <2cm (3.6 mm, $%{\Delta}size=16.9%$, p=0.028). No statistically significant difference was observed for moderately differentiated HCC (5.5mm, p=0.781). However, for well differentiated and poorly differentiated cases, radiographic tumor maximum diameter was significantly larger than the pathological maximum diameter by 3.15 mm and underestimated by 4.51 mm, respectively (p=0.034 and 0.020). Conclusions: A preoperative HCC tumor size measurement using MRI can provide relatively acceptable accuracy but may give rise to discrepancy in tumors in a certain size range or histologic grade. In pathological well differentiated subjects, the pathological tumor size was significantly overestimated, but underestimated in poorly differentiated HCC. The difference between radiological and pathological tumor size was greatest for tumors <2 cm. For some HCC patients, the size difference may have implications for the decision of resection, transplantation, ablation, or arterially directed therapy, and should be considered in staging or selecting the appropriate treatment tactics.

A Study on a paradigm of Radix Aconiti(附子) in the treatment of heart-systemic disease(心系疾患) due to heat syndrome(熱證) (심계영역질환(心系領域疾患) 화열증(火熱證)에 사용된 부자(附子)의 활용(活用)에 대한 문헌적(文獻的) 연구(硏究))

  • Lee, Kyung-Ae;Kweon, Jung-Nam;Lee, Won-Chul
    • The Journal of Dong Guk Oriental Medicine
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    • v.6 no.2
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    • pp.145-165
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    • 1998
  • We inquired into the prescription including Radix Aconiti(附子) on the records of the past. According to the role of Radix Aconiti(附子), we can divide into four group. (1) In the case of excess in the upper and deficiency in the lower(上盛下虛), heat in the upper and cold in the lower(上熱下寒), Radix Aconiti(附子) supplies the fire from the gate of life(命門火) and the fire of deficiency type(虛火) is recurred into the origine(根源) by it. (2) In the case that Yang(陽) is kept externally by Yin(陰)-excess in the interior(陰盛格陽), and there is heat syndrome in the exterior with cold syndrome in the interior(裏寒外熱), Radix Aconiti(附子) can remove cold(祛寒) and revitalizes(回陽). (3) In the case of the heat of excess type syndrome(實熱證), Radix Aconiti(附子) treats heat-syndrome(熱證) with heat-clearing(淸熱) drug. (4) In the case of wind-syndrome(風證) and phlegm-syndrome(痰證), Radix Aconiti(附子) supplies the kidney-Yang(元陽) and promotes movement of the other drugs. According to frequency in use of drugs, we can divide into four group. (1) In e case of the fire of deficiency type(虛火), Radix Aconiti(附子) is used with drugs of invigorating-Yin(補陰), invigorating-Yang(補陽) and diuresis(利水), such as Rhizoma rehmanniae(熟地黃), Cortex cinnamomi(肉桂), Fructus comi(山茱萸), Poria, etc. (2) In the case that Yang is kept externally by Yin(陰)-excess in the interior(陰盛格陽), Radix Aconiti(附子) is used with drugs of dispelling cold(祛寒) and revitalization(回陽), such as Rhizoma zingiberis siccatum(乾薑), Radix glycyrrhizae(甘草), Radix ginseng(人蔘), etc. (3) In the case of the heat of excess type syndrome(實熱證), Radix Aconiti(附子) is used with drugs of heat-clearing(淸熱), such as Rhizoma coptidis(黃蓮). (4) In the case of wind-syndrome(風證) and phlegm-syndrome(痰證), Radix Aconiti(附子) is used with drugs of dispersing(發散), invigorating(補氣), enriching the blood(補血), removing the phlegm(去痰), heat-clearing(淸熱). such as Radix oxterici koreani(羌活), Radix ledebouriellae(防風), Radix ginseng(人蔘), Radix angelicae gigantis(當歸), etc. Especially in many of cases, Radix Aconiti(附子) is used with drugs of nourishing-Yin(滋陰), but it is hardly used with drugs of treating middle-jiao energy(中氣).

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Dosimetric Evaluation of Amplitude-based Respiratory Gating for Delivery of Volumetric Modulated Arc Therapy (진폭 기반 호흡연동 체적변조회전방사선치료의 선량학적 평가)

  • Lee, Chang Yeol;Kim, Woo Chul;Kim, Hun Jeong;Park, Jeong Hoon;Min, Chul Kee;Shin, Dong Oh;Choi, Sang Hyoun;Park, Seungwoo;Huh, Hyun Do
    • Progress in Medical Physics
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    • v.26 no.3
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    • pp.127-136
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    • 2015
  • The purpose of this study is to perform a dosimetric evaluation of amplitude-based respiratory gating for the delivery of volumetric modulated arc therapy (VMAT). We selected two types of breathing patterns, subjectively among patients with respiratory-gated treatment log files. For patients that showed consistent breathing patterns (CBP) relative to the 4D CT respiration patterns, the variability of the breath-holding position during treatment was observed within the thresholds. However, patients with inconsistent breathing patterns (IBP) show differences relative to those with CBP. The relative isodose distribution was evaluated using an EBT3 film by comparing gated delivery to static delivery, and an absolute dose measurement was performed with a $0.6cm^3$ Farmer-type ion chamber. The passing rate percentages under the 3%/3 mm gamma analysis for Patients 1, 2 and 3 were respectively 93.18%, 91.16%, and 95.46% for CBP, and 66.77%, 48.79%, and 40.36% for IBP. Under the more stringent criteria of 2%/2 mm, passing rates for Patients 1, 2 and 3 were respectively 73.05%, 67.14%, and 86.85% for CBP, and 46.53%, 32.73%, and 36.51% for IBP. The ion chamber measurements were within 3.5%, on average, of those calculated by the TPS and within 2.0%, on average, when compared to the static-point dose measurements for all cases of CBP. Inconsistent breathing patterns between 4D CT simulation and treatment may cause considerable dosimetric differences. Therefore, patient training is important to maintain consistent breathing amplitude during CT scan acquisition and treatment delivery.

Analysis of Exploratory Thoracotomy in Non-Small Cell Lung Cancer (원발성 폐암에서의 시험적 개흉술의 분석)

  • 허재학;성숙환;김영태
    • Journal of Chest Surgery
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    • v.32 no.6
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    • pp.536-542
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    • 1999
  • Background: The purpose of this study is to improve the quality of the diagnostic procedures in the preoperative evaluation so as to reduce the unnecessary thoracotomy and to ensure resectability in non-small cell lung cancer. Material and Method: Of 616 patients who underwent thoracotomy for primary lung cancer from January 1990 to December 1996, 59 patients(9.6%) turned out to have inoperable lesions after the thoracotomy. We reprospectively reviewed the bronchoscopic findings, methods of tissue diagnosis, CT scans, pulmonary function test and lung perfusion scan, reasons for nonresectability, and adjuvant therapy, and then followed up on the survival rate after exploratory thoracotomy. Result: The cell types were squamous cell carcinoma in 38, adenocarcinoma in 15, large cell carcinoma in 3 and others in 3. Primary loci were RUL in 20, RML in 6, RLL in 8, LUL in 13, LLL in 4 and others in 8. The reasons for non-resectability were various; direct tumor invaison to mediastinal structures(n=41), seeding on pleural cavity(n=8), poor pulmonary function(n=2), invasions to extranodal mediastinal lymph node(n=2), technical non- resectability due to extensive chest wall invasion (n=3), small cell carcinoma (n=1), malignant lymphoma(n=1), and multiple rib metastases(n=1). In the follow-up of 58 patients, 1-year survival rate was 55.2% and 2-year survival rate was 17.2% and the mean survival time was 14 months. When compared according to cell types or postoperative adjuvant therapeutic modalities, no significant difference in the survival rates were found. The squamous cell carcinoma was frequently accompanied by local extension to contiguous structures and was the main cause of non-resectability. In adenocarcinoma, pleural seeding with malignant effusion was frequently encountered, and was the major reason for non-resectability. Conclusion: These data revealed that if appropriate preoperative diagnostic tools had been available, many unnecessary thoracotomies could have been avoided. Both the use of thoracoscopy in selected cases of adenocarcinoma and the more aggressive surgical approach to the locally advanced tumor could reduce the incidence of unnecessary thoracotomies for non-small cell lung cancers.

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TREATMENT OF MALOCCLUSION, AS RELATED TO FINGER SUCKING : CASE REPORT (손가락 빨기로 인한 부정교합의 치험례)

  • Moon, Sang-Jin;Choi, Yeong-Chul
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.1
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    • pp.1-10
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    • 2004
  • The habit of finger sucking is a reflex occurring in the oral stage, due to nutritive and psychological desire. The habit of finger sucking is considered to be normal till 3 years of age. Dento-skeletal effect on maxillo-mandibular complex including occlusion is naturally correction, when habit stopped before 3 years. If finger sucking continues till $3{\sim}4$ years, Finger sucking leads to severe malocclusion and remarkable discrepancy maxillo-mandibular complex, which is difficult in expectation of natural correction. It is necessary to positive treatment. Treatment of malocclusion, as related to finger sucking is classified two methods. (psychological approach and orthodontic appliance) To stop a habit and to correct severe skeletal discrepancy and malocclusion, $fr\ddot{a}nkel$ appliance is very effective device. This study is to report two cases of treatment of malocclusion, as related to finger sucking. 2 years 10 months old girl with severe overjet, maxillo-mandibular skeletal discrepancy and severe convex facial profile was treated with a FR-II appliance. Finger sucking habit stopped immediately After 16 months, severe overjet, maxillo-mandibular skeletal discrepancy and severe convex facial profile was corrected. 4 years 2 months old girl with midline deviation, mandibular right shift, collateral posterior crossbite and facial asymmetry was treated with a FR-III appliance. Finger sucking habit stopped immediately. After 10 month, Midline deviation, mandibular right shift, collateral posterior crossbite and facial asymmetry were corrected. FR-appliance is a recommendable appliance for a habit breaker and correction of skeletal discrepancy.

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The Clinical Characteristics Between the Positional Obstructive Sleep Apnea Patients with the Non-positional Obstructive Sleep Apnea Patients (체위성 폐쇄성수면무호흡 환자와 비체위성 폐쇄성수면무호흡환자의 임상적 특징 고찰)

  • Kang, Hyeon-Hui;Kang, Ji-Young;Lee, Sang-Haak;Moon, Hwa-Sik
    • Sleep Medicine and Psychophysiology
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    • v.19 no.1
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    • pp.22-26
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    • 2012
  • Objectives: The percentage of positional sleep apnea in obstructive sleep apnea (OSA) varies in different reports from 9% to 60%. If there is a positional dependency in patients with OSA, positional therapy alone could be successful in treating about 50% of all OSA cases. The aim of this report is to compare anthropomorphic and polysomnographic data between the positional sleep apnea group and non-positional sleep apnea group with OSA whose conditions were diagnosed in our sleep clinic. Methods: This is a retrospective study of anthropomorphic and polysomnographic data of patients with OSA who was performed a nocturnal polysomnography. Positional sleep apnea was defined as having a supine apnea-hypopnea index (AHI) of twice or more compared to the AHI in the non-supine position. The patients were divided in the positional sleep apnea group and the non-positional sleep apnea group. Results: In 101 patients with OSA, 81 were male, and the mean age was $49.2{\pm}11.9$ years. Seventy-six (75.2%) were diagnosed as the positional sleep apnea. Waist to hip ratio and body mass index (BMI) were significantly higher in non-positional sleep apnea group. The frequency of severe OSA was significantly higher in this group. In the positional sleep apnea group, nocturnal sleep quality was better preserved, and consequently these patients were less sleepy during daytime. AHI was significantly lower and minimal arterial oxygen saturation during sleep was significantly higher in this group. Conclusion: The percentage of positional sleep apnea in OSA was 75.2%. AHI, BMI, and waist to hip ratio were lower in the positional sleep apnea group. These patients have less severe breathing abnormalities than the non-positional sleep apnea group in polysomnography.

Expression of Tumor Markers and its Clinical Impacts in Resectable Gastric Cancer (절제 가능한 위암에서 종양표지자의 발현과 임상적 의의)

  • Koo Bon Yong;Kim Chan Young;Yang Doo Hyun;Hwang Yong
    • Journal of Gastric Cancer
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    • v.4 no.4
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    • pp.235-241
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    • 2004
  • Purpose: This study was performed to evaluate the effectiveness of the serum tumor markers CEA, CA 19-9, and CA 72-4 in monitoring the recurrence of gastric cancer and in its preoperative assessment. Materials and Methods: Two hundred fifty-five patients who underwent potentially curative surgery during period from January 1995 to December 2000 at the Department of Surgery were assessed. Serum samples were obtained preoperatively, 2 weeks after the surgery, and at 6-month intervals. The cut-off levels were established as 5 ng/ml for CEA, 36 U/ml for CA 19-9, and 4 U/ml for CA 72-4. The tumor stage was described according to the 5th edition of the Union Internationale Contra la Cancer (UICC) TNM classification in 1997. Results: The preoperative positivities were $10.5\%$ for CEA, $9.7\%$ for CA 19-9, and $12.4\%$ for CA 72-4. The serum levels of the three tumor markers decreased after curative surgery. The preoperative serum levels of the three tumor markers were significantly related to the depth of invasion, the tumor size, lymph-node metastasis, the pathologic stage, and recurrence, except that CEA was not associated with tumor size. The marker sensitivities in recurrent cases were $43.3\%$ for CEA, $\%41.8$ for CA 19-9, and $50.0\%$ for CA 72-4, and the marker specificities were $85.1\%$ for CEA, $96.8\%$ for CA 19-9, and $87.8\%$ for CA 72-4. Conclusion: The preoperative serum levels of CEA, CA 19-9, and CA 72-4 are not useful for the initial diagnosis of gastric cancer because of their low positivity. However, we should consider their relationship with depth of invasion, lymph-node metastasis, tumor size, pathologic stage, and recurrence. Also, the follow-up levels of the three markers have a statistical relationship with recurrence of gastric cancer even though their sensitivities are low.

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Effectiveness of Positron Emission Tomography in the Pre-operative Staging of Gastric Cancer (위암환자의 술 전 병기 결정에서 PET-CT의 유용성)

  • Park, Shin-Young;Bae, Jung-Min;Kim, Se-Won;Kim, Sang-Woon;Song, Sun-Kyo
    • Journal of Gastric Cancer
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    • v.9 no.3
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    • pp.110-116
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    • 2009
  • Purpose: The aim of this study was to examine the usefulness of positron emission tomography (PET)-computed tomography (CT) in the pre-operative staging of gastric cancer. Materials and Methods: Between February 2006 and August 2008, PET-CT and CT were performed on 70 patients diagnosed with gastric cancer by gastrofiberscopic biopsy. The sensitivities, specificities, Positive predictive value (PPV), and negative predictive value (NPV) of PET-CT and CT imaging for the detection of gastric cancer TNM staging were compared. Results: The detection rates for the primary tumor were as follows: PET-CT, 81.4% (57/70); and CT, 42.9% (30/70). For both early gastric cancer (EGC) and advanced gastric cancer (AGC), PET-CT was more accurate than CT in detecting the lesions. As the size of the tumor exceeded 3 cm, the detection rate increased. The sensitivities, specificities, PPV, and NPV of PET-CT for lymph node staging were 55.6%, 81%, 86.2%, and 45.9%, while the sensitivities, specificities, PPV, and NPV of CT were 40.0%, 85.7%, 85.7% and 40%, respectively. One case of multiple liver metastasis and two cases of dual primary cancer (rectal and pancreatic cancers) were detected by PET-CT. PET-CT also had a higher detection rate for all histologic types of primary tumors. PET-CT was more accurate than CT in detecting primary gastric cancer lesions. The detection of nodal metastasis by PET-CT was similar to CT; small-sized tumors or EGC detection rates were not high. However, PET-CT provided additional information to detect distant metastases and dual primary cancers and reduced unnecessary laparotomies to detect peritoneal seeding or carcinomatosis. Conclusion: It would be useful to make a pre-operative diagnosis of gastric cancer and determine treatment if PET-CT were added to other routine pre-operative studies.

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